Bacaan Rezumat_en_DASCALU_IONELA_TEODORA.pdf

8/14/2019 Bacaan Rezumat_en_DASCALU_IONELA_TEODORA.pdf

1/69

UNIVERSITATEA DE MEDICIN I FARMACIEGR. T. POPA IAI

FACULTATEA DE MEDICIN DENTAR

ABSTRACT

Contributions to the Study of

Angle Class III Malocclusions

COORDONATOR TIINIFIC:Prof. Univ. Dr. Valentina DOROB

DOCTORAND:Ionela Teodora DASCLU

2010


2/69

1

CONTENT

INTRODUCTION

CHAPTER 1. THE GROWTH AND DEVELOPMENT OFDENTO-MAXILLARY APPARATUS

1.1. The development of cranio-facial elements1.1.1. The development of the cranium base1.1.2. The growth and development of naso-maxillary complex1.1.3. The growth and development of mandible

1.1.4. The temporary development of mandibular articulation1.1.5. The development of dental occlusion1.1.6. The general development of the cranio-maxillo-facial complex

1.2. Essential factors in the cranio-facial growth anddevelopment1.2.1. Intrinsic factors of growth1.2.2. Extrinsic factors of growth

1.2.3. Functional factors in the growth and development of the dento-maxillary apparatus

1.3. Facial rotations of growth1.3.1. Mandibular rotations of growth1.3.2. Growth rotations at the level of the upper jaw1.3.3. Total facial rotations1.4. Theories on facial growth1.4.1. The theory of genetic control (Weinman, Sicher)1.4.2. The theory of growth control by cartilage (Scott).1.4.3. The integralist concept (Enlow).1.4.4. The concept of cybernetic regulation of growth (Petrovic)1.4.5. The theory of functional matrix (Moss)

CHAPTER 2. THE ROLE OF FUNCTIONS,

PARAFUNCTIONS AND DYSFUNCTIONS IN THEDEVELOPMENT OF DENTO-MAXILLARY APPARATUS


3/69

2

2.1. The normal functions of dento-maxillary apparatus2.1.1. Masticatory function2.1.2. Normal breathing function2.1.3. Deglutition function

2.1.4. Phonatic function2.1.5. Mimics

2.2. Pathological functions (Vitiated)2.2.1. Dysfunctions2.2.2. Parafunctions

CHAPTER 3.

THE ETIOPATHOGENY AND DIFFERENTTYPES OF ANGLE CLASS III MALOCCLUSIONS

3.1. The etiopathogeny of Angle Class III malocclusions3.2. Types of Angle Class III malocclusions

CHAPTER 4. THE ROLE OF COMPLEMENTARYINVESTIGATIONS IN DIAGNOSING ANGLE CLASS III

MALOCCLUSIONS

4.1. Complementary investigations in the study of Angle Class IIImalocclusions

4.2. The diagnosis and analysis methods in ANGLE Class IIImalocclusions4.2.1. Diagnosis stages4.2.2. Possible diagnoses in ANGLE Class III malocclusions

CHAPTER 5. THE TREATMENT OF ANGLE CLASS IIIMALOCCLUSIONS

5.1. Factors in choosing an orthodontic treatment

5.2. Growth modification5.2.1. Vertical-horizontal deficiency of the maxillary


4/69

3

5.2.2. Mandibular excess

5.3. Growth prediction and visualisation of treatment objectives

5.4. Estimating treatment response

CHAPTER 6. THE EPIDEMIOLOGY OF ANGLE CLASS IIIANOMALIES

6.1. Goal

6.2. Objectives

6.3. Material and method6.4. Results and discussions

6.5. Conclusions

CHAPTER 7. THE ETIOPATHOGENY, DIAGNOSIS ANDCLINICAL MANIFESTATIONS OF ANGLE CLASS III

ANOMALIES

7.1. The goal of the paper

7.2. Objectives7.2.1. The research of the causes that generate Angle Class IIImalocclusions7.2.2. Clinical manifestations and the diagnosis of each form ofAngle Class III malocclusions

7.3. Material and work method

7.4. Results and discussions

7.5. Conclusions


5/69

4

CHAPTER 8.POSSIBILITIES AND TREATMENT LIMITS INANGLE CLASS III MALOCCLUSIONS

8.1. The goal of the paper

8.2. Objectives8.2.1. Temporary dentition8.2.2. Mixed dentition8.2.3. Permanent dentition8.2.4. The individualised treatment in ANGLE Class IIImalocclusions8.2.5. Fixation in ANGLE Class III malocclusions

8.3. Material and work methods

8.4. ConclusionsCHAPTER 9.RESULTS AND GENERAL DISCUSSIONS

CHAPTER 10. PRACTICAL DIRECTIONS OF PUTTINGINTO PRACTICE THE CONCLUSIONS DEDUCTED FROM

THE STUDY

10.1. Final conclusions

10.2. Practical directions of putting into practice the conclusionsdeducted from the study

BIBLIOGRAPHY


6/69

5

INTRODUCTION

Every dentist should be aware of the basic notions regardingthe formation, growth and development of the dento-maxillaryapparatus in order to understand the modifications that may intervene

or to distinguish the normal variations from the abnormal ones or thepathologic processes.

The dento-maxillary anomalies from the sagittal plane may beconsidered one of the most frequent distortions of the visceralcranium; they are generally known under various designations:dysgnathias, dysmorphoses, and disharmonies. In fact they are theconsequence of a disorder in the development harmony between jaw

and mandible which can be characterised either by an excess or by agrowth deficit of one of the two skeletal entities generatingdimensional disproportions between them.

Protrusive mandible is one of the most common Class IIImalocclusions having a 3% frequency in the general examination ofthe patients and a 25% frequency in the group of subjects sufferingfrom different forms of dento-maxillary anomalies.

There is a high complexity of aetiological factors: general

factors (genetic, endocrine, dysmetabolic) and locoregional factorssuch as: the functional activity (dysfunctions), the integrity state ofthe alveolodental arches, disorders of dental eruption. Together theygenerate dimensional, directional and rhythm disorders of growth.Class III malocclusions are characterised by an exaggerateddevelopment of the mandible in comparison with the upper jaw and

by occlusion modifications: Class III molar and frontal reversedocclusion. Besides facial, endo-oral and occlusal disorders there arealso functional and facial aesthetics disorders.

In this case, the diagnosis of some sagittal dento-maxillaryanomalies becomes a synoptic image of symptoms which presents allthe disorders in the cranium development in all the three directions ofthe space. That is why the data obtained from complementaryexaminations such as profile teleradiography are necessary inestablishing a correct diagnosis.

In order to determine the correct diagnosis as well as thetreatment plan, orthodontists should:


7/69

6

- Recognise the various features of malocclusion;- To define the type of problem including, if possible the

aetiology of malocclusion;- To describe a treatment strategy based on the specific

needs and individual desires.

The treatment of sagittal malocclusions has to be made stepby step, using various and complex medical methods such as general,functional, biomechanical, orthodontic and surgical ones. In order forthe treatment to be successful, orthodontists should be aware of thelimits of all the therapeutical methods mentioned, to know the effectsof their association as well as the best order in which they interact inaccordance with the age and the sex of the patient.

Any treatment in the case of Class III malocclusions isfollowed by a long period of fixation until the growth process iscomplete in order to avoid possible recurrence.


8/69

7

GENERAL PART

Chapter 1. THE GROWTH AND DEVELOPMENT OF THEDENTO-MAXILLARY APPARATUS

1.1. THE DEVELOPPMENT OF CRANIO-FACIAL

ELEMENTS

The formation and modelling of facial skeleton are the resultof cellular multiplication in the osteogenetic centres of encondraland desmal growth, followed by osseous metaplasias at the peripheryof these centres and by a permanent modelling of the relief and of theosseous structures determined by permanent processes of apposition

and osseous resorption.1.1.1. THE DEVELOPMENT OF THE CRANIAL BASE

The normal development of the cranial base determines theformation of cranium and of some nasopharyngeal cavities whichhave the role of assuring the normal function of nervous regulationand the conditions of an adequate respiration and alimentation.

1.1.2. THE GROWTH AND DEVELOPMENT OF NASO-MAXILLARY COMPLEX

1.1.3.The naso-maxillary complex is formed by: the nasal pyramid,

maxillary bones, vomer, zygomatic and palatine bones, the bigsphenoid wings, the lachrymal, the lateral ethmoidal lamina and theinferior concha which make up an osseous complex attached to thecranial base by sutures. The naso-maxillary complex is placed in theinferior part of the face protecting the main sensorial organs: optic,olfactive, auditive and, partially, the gustative one. This complexforms the support of alveolo-dental arches. The musculature ofmimics is inserted in the maxillary complex, which gives expressionto thoughts and human feelings.

On the whole, the naso-maxillary complex develops down

and forward by the related activities of the perimaxillary sutural


9/69

8

system of the coronoid, cranio-facial and incisive-maxillary systempartially obliterated on birth. (Bjrk, 1968).

1.1.4. MANDIBLE GROWTH AND DEVELOPMENT

The mandible body has an encondral development,beneficiating of four growth cartilages for each hemiarch. At eightmonth of intrauterine life, coronoidal and angular cartilages ossify;the shape and dimension of these apophyses will be later onconditioned by the traction forces of masticatory muscles which willact upon the local periosteum as an osteogenetic centre. Theepiphysal cartilage which obliquely unifies the condyle neck with the

ascending branch contributes to the vertical development of the neckcondyle and of the ascending branch of the mandible. This cartilageis functionally stimulated by the pressures exerted by the musclesthat raise the mandible during mastication.

Mandible, the most mobile cranio-facial bone is highlyimportant since it covers the vital functions such as: mastication, themaintenance of airways, phonations and facial mimics.

The various types, mechanisms and centers of mandible

growth are complicated and controversial.

1.1.5. THE DEVELOPMENT OF THETEMPOROMANDIBULAR ARTICULATION

The studies concerned with occlusion development, state thatocclusion and articulation interact with the cranio-facial morphologyduring growth. The adjustment and compensatory changes that take

place contribute to the setting of a normal occlusal functionsustaining the normal articular growth and the physiologicalfunctions.

The effect of displacement, growth and remodelling seem totake place in an anterior-posterior position, despite the localmodifications that take place in different directions. Skeletalmodifications are the result of permanent local remodelling which

produce different modifications from the point of view of volumeand shape.


10/69

9

1.1.6. THE DEVELOPMENT OF DENTAL OCCLUSION

There are three main steps of development that characterisethe alveolodental arches in the ontogenetic evolution:- The formation of temporary arches from birth till the age of 2

years and a half;- The preparation and formation of permanent teeth arches from 2

years and a half to 6 years.- The formation and maturation of permanent teeth arches from 6

to 25 years old.

1.1.7. GENERAL DEVELOPMENT OF CRANIO-MAXILLO-

FACIAL COMPLEXAccording to Hunter and Enlow, the concept of growth

equivalence is an essential element in the understanding of the facialmassif development. There is a strong connection between thedevelopment of one part of the cranium and each zone of the facialmassif. All the movements of bony pieces are coordinated betweenthem.

1.2. DECISIVE FACTORS IN THE CRANIO-FACIALGROWTH AND DEVELOPMENT

1.2.1. INTRINSIC FACTORS OF GROWTH

Intrinsic factors have their origin in the organism itself andmay or may not be influenced by external factors.

Cranio-facial morphogenesis is influenced by the followingfactors:- intrinsic genetic factors;- local and general epigenetic factors;- general and local factors of the surrounding environment.

1.2.2. EXTRINSIC FACTORS OF GROWTH

Nutritional factors


11/69

10

Diet is an effective medication for a child if it is adequatelygiven in a variable quantity. The qualitative, quantitative and

preparation aspects of food are part of the balanced diet whichensures a harmonious development.

Socio-economic factors

Excessive weight and height is statistically related to thesocio-economic conditions. In a steady group some environmentaleffects may be passed on from one generation to another as a resultof genetic and environmental factors.

Psycho-affective factorsThese factors appear in the case of severe deficiencies (the

lack of parent affection or its substitute); as a result, insufficientsecretion of growth hormones may appear ( psycho-social nanism).

1.2.3. FUNCTIONAL FACTORS IN GROWTH ANDDEVELOPMENT OF DENTO-MAXILLARY

APPARATUS

Morphogenesis is the result of the combination betweengenetic and surrounding factors which are represented by bothmuscular activity at rest and active.

Bony tissue behaviour depends on the processes that takeplace in the immediate surroundings. It is sensitive to all variationsregarding repartition of mechanical efforts that it has to endure. Thefunctions are considered to be normal when the muscular actionssuccessfully ensure all the functions that characterise the dento-maxillary apparatus and when these functions are correct.

1.3. FACIAL ROTATIONS OF GROWTH

Cephalometry studies that register the cranium base point out

that mandible is normally guided by the cranium base in an anteriorinferior direction. Thus, mandible body is at a great distance from the


12/69

11

posterior part of the cranium base and the growth of the anteriorheight of the face is bigger than the posterior one; as a consequencemandible sometimes seems to rotate in a posterior way. (Moyers).A significant part of the excessive anterior part is represented by theanterior height of the mandible. On the contrary, when the posterior

height of the face is much bigger then, the tendency is towards deepocclusion and the mandible seems to rotate in an anterior way.

1.3.1. THE ROTATIONS OF MANDIBULAR GROWTH

Bjrk and the associates studied the so called rotations ofmandibular growth by using metallic implants or other methods.

Bjrk made a clear distinction between what he called matrixrotation and intramatrix rotation (Moyers 4-26). Most often,matrix rotation has the form of a pendulous movement having therotation point at the level of the condyle. Intramatrix rotationrepresents the rotation of the mandible body, better said of theinferior half of the matrix and it doesnt take place at the level of thecondyle.

1.3.2. THE ROTATIONS OF GROWTH AT THE UPPERJAW LEVEL

Bjrk studied the dynamics of the upper jaw growth byattaching at least 3 implants.

Thus, he could check: The unequal growth at the median suture; in this case a

transverse hemi rotation takes place the posterior part beingdirected sideways towards each hemi jaw. The growth in length of the jaw takes place at the maxillo-

palatine suture and also by periosteal apposition of the retrotuberosital type to which an oblique dislocation of the boneis associated.

The growth in height is done:- At the level of the peri-maxillary sutures

(fronto-maxillary, maxillo-zygomatic,pterygo-palatine);


13/69

12

- Alveolar bone apposition;- The displacement effect produced by the bony

apposition at the level of the superior orbitarmargin and the resorption of inferior orbitarmargin;

- Resorption at the level of the floor of nasalfossas and apposition at the level of bony

palate;- External apposition;- The vertical contribution of the median suture.

1.3.3. COMPLETE FACIAL ROTATIONS

According to Lavergne and Gasson there are four possiblecombinations if growth rotations are taken into consideration:- The jaw and the mandible have an anterior rotation of growth;- The jaw makes an anterior rotation and the mandible a posterior

one;- The jaw makes a posterior rotation and the mandible an anterior

one;

- Both jaws make a posterior rotation of growth.

1.4. THEORIES ON FACIAL GROWTH

There are concerns related to the elaboration of generalconcepts that may be useful in solving the complexities regardinggrowth tendencies. Their main goal would be that of elaboratingindividual anticipations of growth for both normal patients and

patients that present dento-maxillary anomalies. Different theorieshave been advanced in order to explain these processes of growth.

Chapter 2. THE ROLE OF FUNCTIONS, PARAFUNCTIONSAND DYSFUNCTIONS IN THE DEVELOPMENT OF THE

DENTO-MAXILLARY APPARATUS

Neurological and endocrine disorders as well as thoseconcerning metabolism, irrational and artificial nutrition, the vitiated


14/69

13

functions (oral respiration, infantile deglutition, defective phonation),and the practice of certain bad habits (sucking the finger, the tongue,the cheek or other objects) and bruxism that act upon a labile body(elastopathic one), have a strong negative influence on the dento-maxillary apparatus generating the so called dento-maxillary

anomalies.All these functions, (normal or pathological ones) are the

result of the muscular system which is very well organized (from thesymmetrical, asymmetrical, synergic or antagonistic point of view).It also has a great contribution to guiding the growth, developmentand shape of the dento-maxillary apparatus (teeth, interdental andintercardiac relations, the bones and to a lesser extent the

musculature).Besides the genetic dento-maxillary anomalies, all the othersare initially functional (caused by abnormal behaviour either byvitiating the functions or by practising bad habits). All themorphological changes that affect the dento-maxillary apparatusappear in time.

The influence of the muscular system on the bones has beenknown since the last century. Roux (that was quoted by Boboc, 1996)

issued the law: The form comes out of the function while the formand structure are the result of the function.

2.1. THE NORMAL FUNCTIONS OF THE DENTO-MAXILLARY APPARATUS

They are mainly represented by:- masticatory function;- normal respiration function;- deglutition function;- phonation function;- mimics

2.2. PATHOLOGICAL FUNCTIONS (VITIATED)

Bassigni (1980) divides the pathologic functions of the dento-maxillary apparatus into 2 groups:


15/69

14

- the group of dysfunctions: lazy mastication (includes theartificial feeding of the new-born baby), oral respiration,infantile deglutition and defective phonation;

- the group of parafunctions: the sucking of fingers, of thebedclothes as well as of the different objects, the various

nervous habits and bruxism

Chapter 3. ETIOPATHOGENY AND TYPES OF CLASS IIIMALOCCLUSIONS

Protrusive mandible is one of the most common Class IIImalocclusions with a 3% frequency to a general examination of the

subjects and a 25% frequency in the examination of the group ofsubjects that suffer from dento-maxillary anomalies.There are many etiological factors:- general ones (genetic, endocrine, dysmetabolic);- loco-regional factors:

o the vitiated and pathologic functional activity(parafunctions, dysfunctions);:

o the integrity state of alveolo-dental arches;o dental eruption disorders

All these factors together generate disorders of dimensional,directional and rhythm growth.

Eventually, protrusive mandible is characterised by anexaggerated development of the mandible in comparison to the upper

jaw which leads to molar Class III occlusion transformation andreversed frontal occlusion.

Besides facial, endo-oral and occlusion disorders there arealso functional and facial aesthetic disorders.

Functional disorders include the hyper tonicity or hypotonicity of one of the 4 antagonistic muscular groups, better said tothe sequence of movements done in order to achieve respiration,deglutition, mastication, phonation or facial mimics and by the typeof bad habit. It is important to underline the complex aetiology of

protrusive mandible.


16/69

15

Chapter 4. THE ROLE OF FURTHER INVESTIGATION INTHE DIAGNOSIS OF CLASS III MALOCCLUSIONS

Further clinical and paraclinical investigations are importantin:

- setting a correct diagnosis of dento-maxillary anomaliesand their etiopathogeny;

- choosing the best method of treatment.Teleradiography is:- a method of studying the different parts (soft and tough)

of the dento-maxillary apparatus;- a scientific method of evaluating the different sizes of the

parts that make up the dento-maxillary apparatus (theerrors being of just 0.5mm;- a method of extreme accuracy in predicting the facial

growth until its maturity;- a method of studying occlusion- a method of studying facial aesthetics thus helping in to

establish precise objectives regarding facial harmonyduring orthodontic treatment;

- an important teaching and medical-legal paper.The results of further investigations may be identified in the

morphologic, functional, aetiological, positive and differentialdiagnosis of the anomaly.

There are at least 243 clinical types of Class III malocclusions(Ellis and McNamara); therefore, it is essential to have a goodknowledge of the symptomatology and to interprete all furtherinvestigations correctly.

Chapter 5. THE TREATMENT OF CLASS IIIMALOCCLUSIONS

5.1. DECISIVE FACTORS IN CHOOSING ANORTHODONTIC TREATMENT

Before planning an orthodontic treatment several factors mustbe taken into consideration:


17/69

16

- the patients opinion regarding his/her occlusion andfacial aspect;

- how severe is the skeletal pattern both vertical andantero-posterior since this is one of the greatestdifficulties in setting a correct orthodontic treatment;

- the expectations regarding the antero-posterior andvertical form of growth.

5.2. GROWTH MODIFICATION

The successful treatment of growth modification is possibleonly to patients that present a significant quantity of remaining

growth potential. Growth modification must be done before or duringpuberty before permanent dentition has occurred.

5.3. GROWTH PREDICTION AND VISUALISATION OFTREATMENT OBJECTIVES

The desired positioning of the incisors at the end of thetreatment may be expressed cephalometrically by using the

STEINER analysis in accordance with the ANB angle. This way it ispossible to indicate the right position of the incisors in order toproduce any degree of camouflage for the maxillary discrepancy. Asan objective of cephalometric treatment it is necessary to specify thequantity of change that will be produced during growth and theadditional impact of any treatment regarding growth modification.

5.4. THE ESTIMATION OF TREATMENT RESPONSE

Orthodontists should accept their limits in the skeletalrelation and focus more on dental occlusion. Correction may beobtained by performing dental extraction and tipping teeth by usingorthodontic appliances. Teeth repositioning will have a positiveeffect on facial aesthetics.

The orthodontic treatment must be complex and complete. It

is advisable to apply it before or during the growth of bones:- 7-8 years old during pre-puberty;


18/69

17

- 8-9 years old to girls and 9-10 years old to boys puberty period ;

All should be correlated with somatic development.The orthodontic treatment must also be applied after the

growth period and even later until adolescence. In order to prevent

any possible recurrence orthodontists should have in view an activefixation.


19/69

18

PERSONAL CONTRIBUTION

Chapter 6. THE EPIDEMIOLOGY OF CLASS IIIMALOCCLUSIONS

6.1. GOAL

The goal of the present research is to establish the prevalenceof Class III malocclusions in a sample of infantile population.

6.2. OBJECTIVES

- The study of the prevalence of dento-maxillary

anomalies in a population sample from Craiova and theneighbourhood rural areas;- The evaluation of Class III malocclusions to the

population and children that present dento-maxillaryanomalies;

- To establish the prevalence of Class III malocclusions inaccordance with:- Live environment (source: urban and rural);

- sex;- dentition type (mixed and permanent);- types of Class III malocclusions (I and II).

Dento-maxillary anomalies have lately become more andmore frequent, varying from clinical forms to etiopathogeneticaspects. They have a serious psychic impact on the patient who findsit difficult to integrate in the society, thus we can say that theseanomalies may already be considered a problem of public health.

The prevalence of dento-maxillary anomalies variesaccording to the studied population, age groups, sex, geographicalenvironment, socio-economic and temporal factors.

The epidemiological studies made in Romania pointed out thesame growth tendency of the prevalence of dento-maxillaryanomalies as follows: Shapira 41.9%, Cmpeanu 46.7%, Cocrl 50-60%, Firu and Rusu 75%, Dorob 38.6-76.9% to children with

temporary dentition and 73.6% to permanent dentition.


20/69

19

A study (Dorob)38 which has been recently made on 7 year-old children reveals that 71.6% of the patients have dento-maxillaryanomalies. Taking into consideration the different types of dento-maxillary anomalies the proportion is:

- 44.7% Class I malocclusions;

- 24.6% Class II malocclusions;- 2.3% Class III malocclusions, most of which are

represented by Class III/2 malocclusionsAnalysing the epidemiological studies mentioned above, we

notice a growth tendency of their frequency as well as of theirvariability as far as the clinical forms are concerned.

The frequency of dento-maxillary anomalies is bigger in the

urban area (45%) than in the rural one (20-30%).6.3. MATERIAL AND METHOD

An epidemiological study was made on a group of children(1327 pupils) between 6 and 14 years old (boys and girls) fromCraiova and the neighbourhood areas. The goal of the research wasto identify the prevalence of Class III malocclusions.

6-12year-oldGroup

Group12-14

year-oldGroup

Total %UrbanArea

RuralArea

M F M F833 494

Pupils 1327 - 1033 294399 434 214 280

III/1 3 0.22% 3 0 2 1 0 0

III/2 14 1.06% 9 5 6 5 1 2

Class IIImalocclusions

Total

17 1.28% 12 5 8 6 1 2

Fig. 19 The results of the study made in Dolj County in 2008.


21/69

20

1033 pupils of the grand total of 1327 patients examinedcome from the urban area and only 294 pupils come from the ruralarea.

The investigations revealed 17 children with Class III

malocclusions (1.28%).

without Angle

Class III

malocclusions

1310

98,72%

Angle Class III

malocclusions

17

1.28%

Angle Class III

malocclisions

without Angle Class

III malocclusions

Fig. 21 The statistics of Class III malocclusions

The percentual repartition (for the 17 cases of Class IIImalocclusions) in the urban and the rural area is as follows: 1.16% inthe urban area of 1033 children (fig. 22) and 1.7% in the rural area of

294 children (fig. 23).


22/69

21

Angle Class III

malocclusions

12

1,16%

without Angle

Class III

malocclusions

urban

1021

98,84%

Angle Class III

malocclusions

without Angle

Class III

malocclusions

urban

Fig. 22 The statistics of Class III malocclusions in the urban area.

Angle Class III

malocclusions

5

1,70%

without Angle

Class III

malocclusions

rural

289

98,30%

Angle Class III

malocclusions

without AngleClass III

malocclusions

rural

Fig. 23 The Statistics of Class III malocclusions in the rural area.


23/69

22

Further research highlighted the existence of a great diversityof clinical forms. There were identified 12 cases of Class IIImalocclusions in the urban area, 3 cases representing the 1st

subdivision of Class III malocclusions (0.29%) and 9 cases

representing the 2nd subdivision of Class III malocclusions (0.87%)(fig. 24).

without Angle

Class III

malocclusions

1021

98,84%

malocclusions

III/1

3

0,29%

ma occ us ons

III/2

9

0,87%malocclusions III/1

malocclusions III/2

without Angle

Class III

malocclusions

Fig. 24 The subdivided statistics of Class III malocclusions fromthe urban area.

There were also identified 5 cases of the 2nd subdivision ofClass III malocclusions in the rural area 2 (1.7%) (fig. 25).


24/69

23

without Angle

Class III

malocclusions

289

98,30%

malocclusions

III/1

0

0,00%

malocclusions

III/2

5


malocclusions III/2

without Angle

Class III

malocclusions

Fig. 25 The subdivided statistics of Class III malocclusions in therural area.

Moreover, studying the prevalence of the clinical forms(Class III/1 and III/2 malocclusions) in accordance with the sex ofthe patients we concluded that:

- Of the grand total of 613 boys, 2 cases (0.33%)represent Class III/1 malocclusions and 7 cases (1.14%)represent Class III/2 malocclusions (fig. 26);

- Of the grand total of 714 girls, 1 case (0.14%)represents Class III/1 malocclusion and 7 cases (0.98%)represent Class III /2 malocclusions (fig. 27).


25/69

24

without Angle

Class III

malocclusions

60498,53%

malocclusions

III/1

2

0,33%

malocclusions

III/2

7


malocclusions III/2

without Angle

Class III

malocclusions

Fig. 26 The statistics of Class III malocclusions to boys

malocclusions

III/2

70,98%

malocclusions

III/1

1

0,14%

without Angle

Class III

malocclusions

706

98,88%

malocclusions III/1

malocclusions III/2

without AngleClass III

malocclusions

Fig. 27 The statistics of Class III malocclusions to girls.

Thus, we can conclude that from 17 clinical cases of Class IIImalocclusions (prevalence of 1.28%), 3 cases are Class III


26/69

25

malocclusions of the 1stsubdivision (0.22%), and 14 cases are ClassIII malocclusions of the 2ndsubdivision (1.06%).

The group of children examined was divided into 2 agegroups: 6-12 year-old children (mixed dentition) and 12-14 year-old(permanent dentition). We mainly had in view:

- The total number of Class III malocclusions;- Their repartition in accordance to the sex of the

patients;- The prevalence of Class III malocclusions clinical

forms (1 and 2).

6.4. RESULTS AND DISCUSSIONS

The investigated group was made up of 1327 pupils, 1033being from the urban area and 294 pupils from the rural area; 613were boys and 714 were girls (fig.19).

As far as Class III malocclusions are concerned, the resultsare:

- Of 1327 pupils examined (urban and rural) 17 (1.28%)were identified with class III malocclusions, of which:

o 3 cases (0.22%) were Class III/1 malocclusions(all in the urban area);

o 14 cases (1.06%) were Class III/2 malocclusions(9 cases in the urban area and 5 in the rural one).

- Taking into account the dentition types (mixed andpermanent), the sex, the prevalence of Class IIImalocclusions and also the types of Class IIImalocclusions (1 and 2), the results are the following:

o In the mixed dentition (age group 6-12 yearsold, 833 pupils) there were identified 14 cases(1.68%) of Class III malocclusions:

8 cases to boys, 2 cases of Class III/1malocclusions and 6 cases of ClassIII/2 malocclusions;

6 cases to girls, 1 case of Class III/1

malocclusion and 5 cases of Class III/2malocclusions


27/69

26

o In the permanent dentition (age group older than12 years old, 494 pupils) 3 cases (0.6%) of ClassIII malocclusions:

To boys, 1 case of Class III/2malocclusion and no case of Class III/1

malocclusion; To girls, 2 cases of Class III/2

malocclusions and no case of ClassIII/1 malocclusion.

Comparing the 1.28% value representing the prevalence ofClass III malocclusions on the group of children examined with otherauthors values, we can state that:

- This parameter is close to the 2.3% value (mentioned byPhD Prof. Valentina Dorob)38 at national level;- It is consistant with the value of 1% published by R.

Emrich, A. Brodie, I. R. Blayney;- The frequency of these Class III malocclusions is smaller

in our country than in the countries from Asia (Japan 3-5%, China 1.75%); the explanation may be that theanomalies from the sagittal plane are the result of some

constitution features, race, culture and static life.

6.5. CONCLUSIONS

In conclusion we can state that:- The frequency of Class III malocclusions is a little larger

to children from the urban area; most of them are ClassIII/2 malocclusions. Their main cause may be thesyndrome of premature loss of temporary teeth, newbornartificial feeding or the functional characteristic.functional;

- The balance between Class III/1 malocclusions and ClassIII/2 malocclusions is of 1/4.67 cases; thus, Class III/2malocclusions are more frequent and have more clinicalforms;

- The age group with mixed dentition presents the highestpercent of Class III malocclusions; an explanation might


28/69

27

be given by the various transformations of transitoryintercardiac occlusal contacts and by the practice ofcertain vitiated functions (parafunctions and dysfunctionsthat usually characterize this age when the biggestmorpho-functional imbalances take place at the level of

the dento-maxillo-cranial complex).- The first and most important element when interpreting

the study was the biological parameter of dental occlusion(Angle classification) which generally reflects themorpho-functional imbalances during the growth ofcephalic end;

- The prevalence of dento-maxillary anomalies keeps on

growing which makes us state that this may represent oneof the modern civilisation features;- Worldwide exogamy (mixtures of human races, of

different types of constitutions), worldwide processes ofindustrialisation, the civilisation all together have latelycontributed to the increase of risk factors that producedento-maxillary anomalies;

- Knowing the growth patterns and the development

anticipation of population as well as implementingprophylactic programs represent study tasks and practicaluse of orthodonthics.

Chapter. 7 ETIOPATHOGENY, DIAGNOSIS AND CLINICALMANIFESTATIONS OF CLASS III MALOCCLUSIONS

7.1 THE GOAL OF THE PAPER

There are three important elements that must be known beforeproceeding to establish a correct diagnosis, method and the treatmentway in the case of Class III malocclusion: the cause, the productionmechanism of the malocclusion and its clinical manifestation.


29/69

28

7.2. OBJECTIVES7.2.1. RESEARCH OF THE CAUSES THAT PRODUCE

CLASS III MALOCCLUSIONS

The etiopathogeny of the various clinical forms of Class III

malocclusions in sagittal plane is polygenic and complex, the generalfactors and the loco-regional ones associating and acting together.The result of their actions is in fact a disorder of dimensional growth(either in excess or in minus), of direction, rhythm andunproportional at the level of the constitutive parts of the dento-maxillary apparatus. Thus, real mandibular prognathism presents anexaggerated development of the mandible in comparison to the upper

jaw, occlusion transformation in all the three planes, especially in thesagittal one (Class III molar) and reversed frontal occlusionassociated with functional and facial aesthetics disorders.

7.2.2. CLINICAL MANIFESTATIONS AND DIAGNOSIS OFEACH TYPE OF ANGLE CLASS III MALOCCLUSION

Angle Class III malocclusions (according to Langlade)66 are

sagittal disorders of the following reports:- Maxillo-mandibular;- dento-maxillary.These are marked by:- aesthetic signs:

o concave profile;o upper pro/ retro dentition or both;

- skeletical signs:o with or without, by maxillary distortions in serious

malocclusions;o of mandibular length and position coexisting or

nor with anomalies of maxillary position;- dental signs:

o most often a reversed frontal occlusion;o Class III molar and canine reports.

Mandible may be developed in excess ( real anatomicmandibular prognathism) or may be guided towards anterior by


30/69

29

abnormal occlusal reports (functional protrusive mandible by theinsufficient development of the upper jaw, by abnormal cusprelations by means of ligamentous and intracapsular laxity at theATM level or even by axis modification of the inferior incisivegroup).

7.3. MATERIAL AND WORK METHOD

Along my work years I have formed a group of 10 patientsthat have been examined in order to set a diagnosis based on clinicaland other investigations.

Thus, I discovered the following clinical types of Angle

Class III malocclusions:- Mandibular prognathism Angle Class III /1, 3 cases:o F.O. 268, T.B.;o F.O. 332, B.E.;o F.O. 222, B.L..

- Upper jaw retraction, Angle Class III/2, 3 cases:o F.O. 1022, C.R.;o F.O. 1026, S.P.;o F.O. 1018, N.L..

- Upper jaw retraction with compensatory pro-alveolodentition, Angle Class III/2, 1 case:

o F.O. 1070, C.S..- Mandibular retrusion, Angle Class III/2 Angle, 1 case:

o F.O. 1066, D.A.;- Inferior pro-alveolodentition with frontal reversed

occlusion, Angle Class III/2, 1 case:o F.O. 1006, G.A..

- Bimaxillary pro-alveolodentition with opened frontalocclusion Angle Class III, 1 case:

o F.O. 1076, F.G..

F.O. 268, T.B.

- Age 14 years old;- Sex - male;


31/69

30

- Motivation:o Disorders of facial aesthetics;o Functional disorders regarding mastication,

deglutition (infantile deglutition), phonation,social integration problems;

- General development: tip hypersome, over averageweight in accordance with his age;

- A.H.C.: both parents (especially his father), have thesame somatic development and weight;

- Facial investigation points out a symmetrical face, theinferior floor being high and the labial step reversed. (Fig.28, Fig. 29);

Fig. 28 Initial face photo.

Fig. 29 Initial photo of the right profile


32/69

31

- The development of alveolodental arches: thealveolodental arch of the upper jaw has permanentdentition and is undeveloped in the sagittal andtransversal planes. It also presents dental crowding in thefrontal zone and a slight infraocclusion in the incisive

zone. The dental alveolar arch of the mandible has a verydeveloped alveolar base but all the teeth are lingualisedand there are some teeth crowding in the frontal zone;

- Occlusion diagnosis: molar and canine malocclusioninversely mesialised with slight reversed sagittalinocclusion and slight interincissive occlusion openedfrontally. (Fig. 30, Fig. 31, Fig. 32);

Fig. 30 Initial face model in occlusion.

Fig. 31 Right profile initial model in occlusion.


33/69

32

Fig. 32 Left profile initial model in occlusion.

- The oral investigation consists in:o Ogive vault of medium depth;o Steep and well emphasised alveolar arches;o Big palatal torus, palpable in the medium and

posterior third;o Large, hypertonic tongue;o Impressures of the lingual surfaces on the lingual

edges;o The interposition of the tongue in the incisive zone

(infantile deglutition);o Increased tonus of the circumoral muscles

(orbicular and buccinators ones);- Orthopantomogram: highlights the presence of molar

buds 3 and the mesialised ratios (Fig. 33);


34/69

33

Fig. 33 Initial orthopantomogram

- Initial cephalometric analysis points out (Fig. 34, Fig. 35):o Mesialised occlusal ratios;o The normal development of the upper jaw base,

angle SNA= 83;o The slight development of the mandibular base,

angle SNB= 88, with angle ANB= -5, whichshow the intermaxillary discrepancy from the

sagittal plane (thus, Angle Class III malocclusion);o Angle FMA= 34 (+9), hyperdivergent type, thus

a growth of the facial massif mainly downwardand forward and a serious diagnosis of the facialmassif development;

o Angle FMIA= 71 (+6);o Angle IMPA= 76 (-14), inferior retraction which

is the cause of the slight frontal mandibular teethcrowding;

o Angle axI/plF= 120;o Nsa Nsp= 5,5 cm.;o Go Gn= 9cm.;


35/69

34

Fig. 34 Initial radiograph.

Fig. 35 Initial radiograph interpretation.

- Neuro-endocrine investigation: a slight hyperfunction ofhypophysis at the anterior lobe ;


36/69

35

- Morphologic diagnosis: Angle Class III/1 malocclusionwith a frontally opened occlusion, laterally reversedocclusion and reversed sagittal inocclusion;

- Etiologic diagnosis: Angle Class III/1 malocclusionprobably caused by the associated action of the following

factors:o General: the hyperfunction of the hypophysary

anterior lobe that secretes a high quantity ofsomatotrophic hormone;

o Loco-regional: the persistence of infantiledeglutition and the vicious habit of biting the jugaland labial mucosa;

- Functional diagnosis: the following functions areaffected:o Deglutition function by the persistence of infantile

deglutition;o Phonation function by the pronunciation of sibilant

consonants;o The masticatory function of incesting the food

determined by an interincissive opened occlusion;o Aesthetic function;o The function of social integration in collectivity.

F.O. 1018, N.L.

- Age: 13 years old;- Sex: female;- Motivation:

o Disorders of facial aesthetics ;o Functional disorders: of mastication, phonation

and social integration;- A.H.C.: not important;- General development: normosome type, normal weight;- Facial investigation reveals: flat features, a slight concave

profile, the equality of face floors, superior retro baldness

generating the inversion of labial step, Gn placednormally (Fig. 72);


37/69

36

Fig. 72 Initial photograph right profile.

- The development of alveolodental arches: the alveolararch slightly reduced in comparison to the coronoid arch,dento-alveolar disharmony with slight dental crowding,reversed frontal occlusion and mesialised occlusiontowards the right;

- Occlusion diagnosis: mesialised malocclusion bilaterallymarked at the level of molars and canines with frontalreversed occlusion and a slight frontal reversed overbite.(Fig. 73, Fig. 74, Fig. 75);

Fig. 73 Face in occlusion initial model.


38/69

37

Fig. 74 Right profile in occlusion initial model.

Fig. 75 Left profile in occlusion initial model.

- The oral investigation consists in:o Deep vault palatine;o Well represented alveolar arches;o Absent palatine torus;

- Orthopantomogram reveals (Fig. 76):o The absence of molar buds 3;o The atrophy of alveolar mandibular limbuses;o The descent of epithelial insertions;


39/69


40/69

39

Fig. 77 Initial radiograph.

Fig. 78 Interpretation of initial radiograph.

- Morphologic diagnosis: Angle Class III/2 malocclusionwith upper jaw retrusion;


41/69

40

- Etiologic diagnosis: Angle Class III/2 malocclusioncaused by:

o Hyper tonicity of the superior orbicular muscle;o Congenital factor;

- Functional diagnosis: the following functions are

affected:o Masticatory function;o Aesthetic function;o Phonation function;o The function of social integration in collectivity;

7.4. RESULTS AND DISCUSSIONS

The study was made on a group of 10 patients both male andfemale that presented malocclusions in the sagittal plane; their agewas between 11 and 23 years old. (Fig. 110).No

.Crt

No.F.O.

Namefirst

name,Sex, Age

Diagnosis ofAngle Class IIImalocclusion inthe sagittal plane

Etiopathogeny

1 268 T.B.M14

Angle Class III/1malocclusion

Endocrine factor: thehyper function of thehyphophysary anteriorlobe; loco-regionalfactors: infantiledeglutition, the

parafunction of biting

the upper lip,macroglossia, the badhabit of protruding themandible

2 332 B.E.F11


Endocrine factor:hypothyroidism; loco-regional factors:sleeping with the head

in hyperflexis, theparafunction of biting


42/69

41

the upper lip,macroglossia

3 222 B.L.F12


Endocrine factor:hypothyroidism;hereditary function:

mother presentedAngle Class III/1malocclusion; loco-regional factors: the

parafunction of bitingthe upper lip,macroglossia and

muscular hypo tonicity4 1022 C.R.M11

Angle Class III/2malocclusion,upper jawretraction withfrontal reversedocclusion

Hereditary function:mother presented asimilar malocclusion,mongoloid facial type,;loco-regionalhypertonicity of superior orbicular

muscles5 1026 S.P.

M14

Angle Class III/2malocclusion,upper jawretraction withreversed frontalocclusion

Hereditary function:mother presented asimilar malocclusion,mongoloid facial type,;loco-regionalhypertonicity of

superior orbicularmuscles6 1018 N.L.

F23

Angle Class III/2malocclusion,upper jawretrusion withreversed frontalocclusion

Hereditary function:mother presented asimilar malocclusion,mongoloid facial type,;loco-regionalhypertonicity of

superior orbicularmuscles


43/69

42

7 1070 C.S.F23

Angle Class III/2malocclusion,upper jawretrusion withmaxillary and

compensatoryproalveolo-dentition

Loco-regional factors:macroglossia, infantiledeglutition, open bite

8 1066 D.A.M12

Angle Class III/2malocclusion,mandibularretraction

Loco-regional factors:the hypertonicity ofsuperior orbicularmuscles and the

hypertonicity ofretrusionarymandibular muscles

9 1006 G.A.M12

Angle Class III/2malocclusion,inferior

proalveolodentition with reversed

frontal occlusion

Loco-regional factors:the hypertonicity ofsuperior orbicularmuscles and the badhabit of biting the

upper lip10 1076 F.G.

M21

Angle Class III/2malocclusion,

bimaxillaryproalveolodentition with openfrontal occlusion

Loco-regional factors:the hypertonicity ofsuperior and inferiororbicular muscles, oralrespiration andinfantile deglutition

Fig. 110 Table of the patients centralised data.In the above mentioned table we can remark that the average

age of the patients that presented to orthodontic consultation insearch for a treatment was of 14 years old and 3 months when thegrowth process had already stopped.

The etiopathogeny of these clinical forms of malocclusions inthe sagittal plane is complex and diversified.


44/69

43

The variety of etiopathogenic factors consists in the greatnumber of causal, general (genetic, endocrine, dysmetabolic) andloco-regional factors:

- parafunctions;- dysfunctions;

- disorders of vertebral statics and an increasing ordecreasing tonus of the following muscles: lingual, labial,

propelling or retrusional muscles of the mandible;- less numerous factors but probably undetected in

anamnesis (inflammatory factors, the integrity state ofalveolo-dental arches, dental eruption disorders, cheloidscars of muscular girths);

- the transformation of the functional underhung jaw into areal one.The seriousness of etiopathogenic factors consists in their

cumulative action which leads to a vicious circle that intervenes inthe growth processes of the dento-maxillary apparatus, modifyingtheir dimension, growth direction and rhythm.

7.5. CONCLUSIONS

The etiopathogeny of malocclusions from the sagittal plane isdiversified and complex due to the big number of causal factors:

- general ones:o genetic;o endocrine;o dysmetabolic;

- loco-regional factors:o vitiated functions (oral respiration, infantile

deglutition);o dysfunctions (the bad habit of propelling the

mandible, vicious habits: biting the lips, suckingthe fingers);

o vertebral statics disorders during sleeping time(bent head);

o the lack of abrasion at canines cusps ;o disorders of the teeth integrity state;


45/69

44

o disorders of dental eruption;o inflammatory factorso cheloid scars of the labio-genio-pharyngeal

muscular girth;o cheilo-gnatho-palatal clefts.

Causal factors usually associate and act in the growth anddevelopment period of the dento-maxillary apparatus generatingmultiple changes.

Dimensional, form, rhythm and growth changes also apply toall the basic components of the dento-maxillary apparatus: (bones,muscles, intermaxillary reports and alveolo-dental arches).

When patients present to orthodontic consultation all these

factors have already produced essential changes to the elements ofthe dento-maxillary apparatus.One of the main reasons is the lack of specialized dental

hygene education in the large groups of children (children nurseries,kindergartens and schools) as well as the diagnosis and guidance ofthe cases towards orthodontic consultations.

The clinical manifestations are diverse and specific to eachclinical form of Angle Class III Malocclusion but the positive

diagnosis is set only after further cephalometric analyses.

Chapter. 8 POSSIBILITIES AND LIMITS OF TREATMENTIN ANGLE CLASS III MALOCCLUSIONS

The objectives, methods and treatment possibilities have to beassociated with:

- the type of anomaly or better said the clinical form;- the seriousness of the anomaly;- patient age, dentition type (temporary, mixed,

permanent);- socio-economic factors.


46/69

45

8.1. THE GOAL OF THE PAPER

The goal of the present paper was to evaluate the methods andmeans of treatment used in the treatment of Angle Class IIIMalocclusions

8.2. OBJECTIVES

- to evaluate the results obtained in the treatment of AngleClass III malocclusions by using orthodontic andorthopaedic means: functional and biomechanical;

- to evaluate the treatment means used in fixed therapy.

8.2.1. TEMPORARY DENTITION8.2.1.1. PROPHYLACTIC TREATMENT

Whenever one of the elements from the dento-maxillaryapparatus grows more than the other one, following a differentdevelopment rhythm determined by genetic or functional factors,there is the danger of generating a malocclusion in the sagittal plane.

The therapeutical attitude in this case consists in controllingthe occlusion, in following a general medical investigation in order toexclude neuro-endocrine or metabolic factors. There are many

prophylactic methods of treatment such as: keeping record andcontrol of all these children, following a general medical treatment(in cases of endocrinopathy, rickets) or a simple orthodontictreatment that can correct a bad habit that may affect the normalfunctions of the dento-maxillary apparatus.

Successful prophylactic measures applied to school andpreschool children could reduce considerably the great number ofdento-maxillary anomalies, being the most economic and efficientmeans of treatment.


47/69

46

8.2.1.2. THERAPEUTICAL ASPECTS OF FUNCTIONALPROTRUSIVE MANDIBLE

The reversed frontal occlusion which is a clinical sign offunctional protrusive mandible of cusp guidance is quite a frequent

anomaly in temporary dentition.The factors that generate the anomaly to preschool children

must be known before proceeding to causal and functional therapies.Early treatment should be applied in the initiation stage of the

disharmony in order to obtain a normal incisive report not later thanthe eruption of permanent incisors. The disharmony can be noticed inthe initiation stage when there is a strong propelling tendency of the

mandible in order to search for a comfortable position in the absenceof the inferior abrasion of temporary canines or when the reversedocclusion is already set but the retrusion test is positive. Removingthe cusp slopes of inferior temporary canines that lack the abrasion ofstripping is enough. Stripping is to be done in stages, taking intoaccount the childs sensitiveness as well as the tooth anatomy. At thesame time, the occipito-mental traction is associated with chin capand headcap in order to prevent the propelling habit and to limit the

large openings of the mandible. It is recommended a constant use ofthe chin cap (during the day, the night or the meals of the day) atleast 3 months in accordance with the severity of the case and the

patient reaction.

8.2.2. MIXED DENTITION

8.2.2.1. THE TREATMENT PLANNING IN MIXEDDENTITION

In the mixed dentition the treatment doesnt inhibit thenormal development of dentition. The emphasis should be on theguidance of growth, on the interception of a developmentmalocclusion and on the elimination of any symptoms that can turninto a serious occlusion matter in the permanent dentition.


48/69

47

The early fundamental objective of Class III is that ofcreating an environment in which a favourable dento-facialdevelopment appears.

8.2.2.2. THE GOALS OF INTERCEPTIVE TREATMENT

The goals of interceptive treatment may include:- to prevent irreversible pregressive modifications of bony

and soft tissues;- to improve the skeletal discrepancies and to produce a

favourable environment for future growth;

- to improve the occlusal function;- to simplify the second stage of treatment;- to minimize the necessity of a surgical and orthopaedic

treatment;- to obtain a pleasant facial aesthetics thus contributing to

the psycho-social development of the child.

8.2.2.3. THE INCIPIENT PHASE OF MIXED DENTITION

(THE FIRST STAGE)

During mixed dentition, there are also other modificationsand consequences after extractions such as: dento-alveolarincongruity and opened occlusion which require an individualisedtherapy. The treatment period mainly depends on the clinical form,the degree of modifications and the complexity of the clinical chart.The treatment period may be between 5 months and 4 years.

The treatment may be considered successful if one of thefollowing conditions is fulfilled:

- the primary etiological factors were removed orcontrolled;

- the teeth positions and the necessary space are satisfyingand can be maintained until the end of mixed dentition;

- the initially presented skeletal deviations were improved

to the initially planned degree and extent and can be


49/69

48

controlled until dentition has completed and the skeletalgrowth diminished.

8.2.2.4. THE LATE PHASE OF MIXED DENTITION (THESECOND STAGE)

The early treatment of Class III chin-headcap and functionalappliances of expansion based on dento-facial orthopaedics is only

partially successful because the highest degree of efficiency isobtained between 11 and 13 years old.

To patients that had precocious correction of their incisiverelation the treatment is continued in order to solve the crowding and

align the rest of the teeth. If the overbite is small a fixed appliancemay be used by bracing all superior incisors. The vertically anteriorgrowth of the face reduces the overbite which diminishes the risk ofrecurrence.

In order to choose the best treatment (that of correcting thenegative overbite) a surgical modelling of the skeleton helps inestimating the future facial aspect. This estimation must be donewhen the mandible is at rest in order to avoid obtaining a fake image

because of the anterior movement of the mandible in maximuminterdigitation.

8.2.3. PERMANENT DENTITION

8.2.3.1. ORTHODONTIC ORTHOPAEDIC TREATMENT

A malocclusion that presents a slight mandibular prognathismand a moderate overbite may be corrected by dento-alveolarmovements. Class III elastics with or without extractions may beused to cover the skeletal discrepancy towards an acceptable facial

profile.Class III malocclusions with a slight mandibular prognathism

and crowding may be treated by extractions of the second maxillarypremolar and first mandibular premolar.

In the most severe cases when the overjet can not becorrected by a simple inclination of superior incisors (where the


50/69


51/69

50

8.3. MATERIAL AND WORK METHODS

I treated 19 patients (in my private consulting room or at theOrthodontic Clinic from the Faculty of Dental Medicine Craiova)suffering from dento-maxillary anomalies in sagittal plane, 10 being

selected for the present PhD research paper.The used method of treatment was the technique of right arch,

the treated patients having permanent dentition.The objectives of fixed therapy were different (for each and

every patient) in accordance with the clinical type of Angle Class IIImalocclusion.

F.O. 268, T.B.- Diagnosis: Angle Class III/1 malocclusion, mandibular

prognathism, frontal open occlusion and reversed sagittalinocclusion;

- Treatment: fixed therapy, Straight-wire therapy with thefollowing objectives (Fig. 111, Fig. 112):

o The expansion of the alveolo-dental arches of the

upper jaw;o The alignment of maxillary and mandible frontal

teeth;o Intermaxillary elastic tractions Class II;o Intra-extra oral tractions with the Delaire mask;o To reduce the opened frontal occlusion and the

reversed sagittal inocclusion;

Fig. 111 Photograph of open mouth during treatment.


52/69

51

Fig. 112 Photograph face in occlusion during treatment.

- The interpretation of radiograph 2 after 5 years oforthodontic treatment and comparing the values of theseangles with the ones from the first radiograph we noticetheir recovering to normal values (Fig. 113, Fig. 114):

o Angle SNA= 83;o Angle SNB= 85;o Angle ANB= -2;o Angle FMA= 28;o Angle FMIA= 63;o Angle IMPA= 89;o Angle axI/plF= 118;o Nsa Nsp= 5,5 cm.;o Go Gn= 9cm.;


53/69

52

Fig. 113 Final radiograph.

Fig. 114 Interpretation of final radiograph.

- The fixation will be on a long period of time until thegrowth of the mandible stops. (27 years old).


54/69

53

F.O. 1018, N.L.

- Diagnosis: Class III/2 malocclusion, retraction of upperjaw;

- Treatment: fixed orthodontic therapy which had the

following objectives (Fig. 134, Fig. 135, Fig. 136):o The development of upper jaw in sagittal and

transversal plane;o Getting the occlusion reports from sagittal and

transversal plane to a normal state;o Ensure a frontal overcover of at least 1/3 of the

inferior frontal teeth height;

Fig. 134 Face photograph ofopen mouth at the end of the treatment.

Fig. 135 Photograph face in occlusion at the end of the treatment.


55/69

54

Fig. 136 Photograph left profile at the end of the treatment.

- Radiograph 2 proves the normal values of thecephalometric angles (Fig. 137, Fig. 138):

o Angle SNA= 82;o Angle SNB= 80;o Angle ANB= +2;o Angle Go= 124;o

Angle FMA=33;o Angle FMIA= 61;o Angle IMPA= 87;o Angle I/i= 120;o Angle i/N-B= 24;o Angle plM/plN-S= 38;o Nsa Nsp= 5,2 cm.;o Go Gn= 9,2 cm.;


56/69

55

Fig. 137 Final radiograph.

Fig. 138 Final radiograph interpretation.

- By fixation we referred to the maintenance of the fixedappliance up to 18 years old. Fig. 139 reveals themaintenance of occlusal reports, the photograph beingtaken at 20 years old.


57/69

56

Fig. 139 Photograph face in final occlusion.

8.4. CONCLUSIONS

Of the total number of cases investigated, 3 represent AngleClass III/1 malocclusions and the rest of 7 cases are Angle Class III/2malocclusions. The main clinical form is upper jaw retrusion.

In the same subdivision Angle Class III/2 malocclusions wecan also include pseudoprotrusions that guide the mandible (thegroup of functional mandibular protrusions), the mandibular condyle,or simply the mandible towards the so called premature contacts in

the closing movement of the mouth (steep cuspian slopes).Another clinical form of functional pseudoprotrusion isproduced by changes of the axis of frontal teeth eruption thusreversed interlocking of frontal dental groups.

These clinical forms of pseudoprotrusions are easilydiagnosed and the treatment can be done by any dentist if discoveredin time. Still when they are not discovered and treated at the righttime, they may turn into Angle Class III/1 malocclusions.

Chapter 9. RESULTS AND GENERAL DISCUSSIONS

Our epidemiological study had in view a sample of 1327pupils (boys and girls) between 6 and 14 years old from Craiova andthe neighbourhood area. The result emphasized a 1.28% prevalenceof Angle Class III malocclusions. This percent may vary in

accordance with:


58/69

57

- Life environment (urban 77.84% and rural 22,16%), arethree and a half times bigger in the urban area than in therural one, because of the following aspects:

o The agitated, stressful life environment of bothmother and child;

o Artificial feeding of newborn baby which is veryfrequent nowadays and thus the bad habits thatmay appear from this age;

o Combinations of genes as a result of mixedpopulations;

o The great number and variety of clinical forms thatcharacterize Angle Class III malocclusions (243 of

clinical forms according to Ellis andMcNamara)40;- Age group;- Insufficient sanitary education;- A lack of specialized dentists especially in the large

groups of children (in kindergartens and schools).The presented cases highlight the complex etiopathogeny of

Angle Class III malocclusions, of internal (neuro-endocrine) and

external factors (the normal and pathologic functions). They workaltogether in the adapting and modelling process of the individualgenetic inheritance. .

Except for the genetic malocclusions, all the rest of dento-maxillary anomalies are initially functional, the morphologic changesappearing later in time.

The specific normal functions of the dento-maxillaryapparatus interrelate with the help of the muscular system which isorganised in such a way that the bones are inserted in a musculartunnel and are influenced by the above functions in the process ofgrowth, development and modelling.

The vitiated functions act in the same way but develop themaxillary bones in a different direction, influencing the individualgenetic pattern. However, not all children with bad habits developmalocclusions. The answer may be found in the resistance of genetic

pattern (V. Dorob)38

. If the genetic pattern is overcome, theseriousness of the anomaly will depend on the following three


59/69

58

elements: frequency, intensity, and the length of time to practise thevitiated functions. (according to Graber, quoted by V. Dorob)38.

The great number of causal factors and their complexity aswell as their concentrated and cumulative action determines disordersof dimensional growth and rhythm at the level of maxillaries leading

to dimensional disproportions of the maxillaries and the mandible.One of the main features of Angle Class III malocclusions is

that they become more and more serious as the time passes by thus itis important to discover them as early as possible.

Functional mandibular protrusion is a relevant example in thissense.

There are at least 243 clinical forms of Angle Class III

malocclusions (according to Ellis and McNamara)

40

proved by a deepknowledge and a correct interpretation of complementaryinvestigations. They may also result from the confirmation of themorphologic, functional and etiological diagnosis of Angle Class IIIanomaly.

I consider important to mention that the correct interpretationof further investigations such as :(model analysis, photographanalysis, orthopantomogram and radiograph analysis as well as

cephalometry) constituted valuable papers in establishing a correctdiagnosis and therapeutical method.

I also had in view the possible recurrence of malocclusions(having to do with very serious skeletal anomalies) and the differentgrowth of the two jaws, the mandible growing up to 27-28 years oldwhile the upper jaw stops growing at the age of 18. Thus fixationappliances are compulsory for a long period of time even for alifetime.

The studied cases benefitted from orthodontic treatment,mainly the Straight-Wire method.


60/69

59

Chapter 10. FINAL CONCLUSIONS AND PRACTICALDIRECTIONS OF APPLYING THE CONCLUSIONS

DERIVED FROM THE STUDY

10.1. FINAL CONCLUSIONS

The epidemiological results of the sample of investigatedchildren revealed a prevalence of 1.28% Angle Class IIImalocclusions.

Angle Class III malocclusions may be differentiated accordingto:

o Clinical forms: Angle Class III/1 0.22%, Angle

Class III/2 1.06%;o The source environment: urban 77.84%, rural22.16%;

o Correlation between Angle Class IIImalocclusions and the source environment:

Urban: Angle Class III/1 Angle 0.29%,Angle Class III/2 0.87%, withoutAngle Class III malocclusions 98.84%;

Rural: Angle Class III/1 Angle 0.00%,Angle Class III/2 1.7%, without anyAngle Class III malocclusions 98.3%;

o Correlation between the clinical forms ofAngle Class III malocclusions and sex:

Boys: Angle Class III/1 0.33%, AngleClass III/2 1.14%, without any AngleClass III malocclusions 98.3%;

Girls: Angle Class III/1 0.14%, AngleClass III/2 0.98%, without any AngleClass III malocclusions 98.88%;

The main clinical forms are represented by Angle Class III/2malocclusions (pseudoprotrusions) which appear in infancy;they may be easily discovered and treated by short term

preventive treatments;


61/69


62/69

61

treatment strategies are changed in the favour of earlyorthodontic therapy as soon as possible;

As a consequence, the medical consulting rooms from theschool network should be extended and the hygene educationshould be encouraged;

The clinical forms of Angle Class III/1 and Angle Class III/2malocclusions (upper microretrusion) have as essentialetiopathogenetic element the genetic factor;

The evolution factors of the dento-maxillary apparatus andthe local pathologic factors act together with the geneticfactor transforming the malocclusion from the sagittal oneinto a very serious anomaly;

The great number and the various types of clinical forms areamplified by the directional and quantitative imbalance ofgrowth in the relation of interdependence between themaxillary, tooth and muscle which are reflected in the dentalocclusion thus, the term malocclusion being the mainlyused designation for dento-maxillary anomalies;

The diagnosis for Angle Class III malocclusion is establishedin the view of finding the nucleus of the disorder by using

paraclinical investigations (photographs, model analyses, aseries of retro-dento-alveolar radiographs,orthopantomograms, teleradiographs, cephalometry,electromyography and even tomography) and the clinicalexamination.

The treatment is specific to each and every individual; mostof the time, the fixed therapy is associated with the mobileone by using intra-extra oral tractions and in some case evensurgical intervention;

The balance obtained must be morphological and functionaltaking into consideration the aesthetic, functional andstability;

The period of active treatment may vary in accordance withthe age and the type of dentition, with the physiologicalgrowth access and the way the patient obeys the treatment

indications;


63/69

62

Although the patient adheres to treatment rules there may bethe risk of recurrence especially in the period the temporarydentition is replaced by the permanent one or during theeruption of molars 3; as a consequence a long fixation isnecessary at least until 27 years old when the growth

potential of condylian cartilage is assumed to stop; there aresome cases when fixation is recommended for good in orderto avoid surgical intervention;

Mobile as well as fixed appliances were used (depending onthe case) for the fixation period;

The fixed retainer cannot be noticed and is very safe makingthe patient feel comfortable.

10.2. PRACTICAL DIRECTIONS OF PUTTING INTOPRACTICE THE CONCLUSIONS DEDUCTED FROM THE

STUDY

The conclusions regarding the epidemiology of Angle ClassIII malocclusions, the prevalence of the clinical forms as reported totheir environmental origin, age, sex are the first studies of this type

made in Oltenia and may be taken into consideration as referencepoint for further research. The results of this epidemiological studytogether with the national specialized literature may contribute todecision making in elaborating the programs of national sanitary

policy.This epidemiological study is focused only on the discovery

of clinical forms regarding Angle Class III malocclusions, the onlystudy in the specialized literature being made by PhD Prof. V.Dorob38.

The research may be extended in the future and associatedwith other forms of malocclusions (Angle Class I and II). The greatnumber and the various clinical forms of Angle Class IIImalocclusions represent the starting point of a research that may beextended.

Angle Class III malocclusions are perhaps one of the most

serious malocclusions and the approaches made in order to conceivethe orthodontic file may be extended in subsequent studies.


64/69

63

BIBLIOGRAPHY

1. BASIGNY F. Manuel dOrthopedie Dento-Faciale, Ed.Masson, Paris, 1991;

2. BISHARA S.E. Textbook of Orthodontics, Ed.

W.B.Saunders Co., Philadelphia, 2001;3. BJRK A., SKIELLER V. Facial development and tooth

eruption, Am. J. Orthod., 62, 4, 339,1972;4. BLOOMER H. Spech defects in relations to orthodontics,

Am. J. Orthod., 12, 920, 1963;5. BOBOC Ghe. Anomaliile dento-maxilare, Ed. Medical,

Bucureti, 1971;

6. BOBOC Ghe. Aparatul dento-maxilar. Formare idezvoltare, Ed. a 2-a, Ed Medical, Bucureti, 1996;7. CAUHP J., WALLOT J.J. A propos de deux

observations orthodontiques avec un troubles transversaldarticul, Rev. Stomat., Paris, 3, 233, 1969;

8. CHATEAU M. Orthopedie Dento-Faciale, vol. 1, Ed. CdP,Paris, 1994;

9. COCRLA Elvira Stomatologie Pediatric, Ed. Medical

Universitar J.Haieganu, Cluj-Napoca, 2000;10. COSTA E. Raionamentul medical n practica

stomatologic, Ed. Medical, Bucureti, 1970;11. COSTA P., TERESA M., Josep M Ustrell Torrent, Correia

Pinto Orthodontic camouflage in the case of a skeletal classIII malocclusion, World Journal of Orthodontics, 5, 3, 213-223, 2004;

12. COZZA P., BRAMA L., ROSIGNOLI L., LAGANA G. Ilcontrolo della crescita mandibolare nelle III classi. Revisionedella literatura e considerazioni cliniche, Mondo-Ortodontico,22, 5, 431-441, 1997;

13. COZZA P., GIANCOTTI A. Disarmonie di classe III.Eziopatogenesi e motivazioni al trattamento precoce, Mondo-Ortodontico, 23, 4, 245-255, 1998;

14. CUUI M., NETIANU V., TR M.

Electromiografia computerizat n patologia ortodontic, Ed.Aius, Craiova, 1997;


65/69

64

15. DEGUCHT T., McNAMARA J.A. Craniofacialsadaptations induced by chincup therapy in class III patients,Am. J. Orthod. Dento-Fac. Orthop., 115, 175-182, 1999;

16. DELAIRE I. - Lintrication des fonctions de lextremitecephalique et les inter-relations morpho-fonctionnelles oro-

faciales, Lorthodontie Francaise, 55, 1: 48-52, 1984;17. DIEDRICH Peter Bracket Adhasivtechnick in der

zahnheilkunde, Hansen Verlag, 1983;18. DOROB Valentina, PASNICU Letiia, PSREANU

Marinela, CURA Eugenia Prima perioad a dentiiei mixte:o abordare ortodontic, Rev. Stomatologie, 1, 69-77, 1987;

19. ELLIS E., McNAMARA jr. J.A. Components of adult class

III open-bite malocclusion, Journal of oral and maxillofacialsurgery, 42, 295-305, 1984;20. ENLOW D.H. Facial growth, Ed. W.B. Saunders, Londra,

1990;21. FIRU P. Introducere n studiul anomaliilor dento-maxilare,

Ed. Academiei, Bucureti, 1981;22. FRATU A.V. Creterea i dezvoltarea post-natal a

aparatului dento-maxilar, Ed. Vasiliana 89, Iai, 2001;

23. FRATU A.V. Ortodonie. Diagnostic, Clinic, Tratament,Ed. Vasiliana, Iai, 2002;

24. GRABER L.W. Chincup therapy for mandibularprognatism, Am. J. Orthod., 72, 1, 23-41, 1977;

25. GRABER T., RAKOSI T., PETROVIC G. Dentofacialorthopedics with functional appliances, Ed. Mosby, St. Louis,1985;

26. GRABER Th.M., VANARSDALL R.L. OrthodonticsCurrent Principles and Thechniques, Ed. The C.V. MosbyComp. St Louis, 1994;

27. GRIVU O., MECHER E., ARDELEAN A. Aspectepractice n ortodonia interceptiv, Stomatologie, 4, 313-319,1978;

28. GRIVU O., STROE Maria, BRATU Elisabeta, VEINMariana Tratamentul ortodontic precoce n colectivitile de

copii precolari, Stomatologie, 2, 139-145, 1984;


66/69


67/69

66

42. MILICESCU Viorica, MILICESCU Duduca Ioana Creterea i dezvoltarea general i cranio-facial la copii,Ed. Viaa Medical Romneasc, Bucureti, 2001;

43. MOSS M.L. Function-fact or fiction, Am. I. Orthod., 67,6:625-647, 1975;

44. MOSS M.L. The primary of functional matrices in oro-facial growth. Practtioner, 19: 65-74, 1968;

45. MOSS M.L., SALENTI I.N. The primary role of functionalmatrices in facial growth, Am. I. Orthod., 55, 6: 566-577,1968;

46. MOSS M.L., SKALAK R. Space-time in cranio-facialgrowth, Am. I. Orthod., 77, 6: 591-613, 1980;

47. MOYERS R.E. Handbook of orthodontics, Ed. Year-BookMedical Publishers Inc., Chicago, 1998;48. NAGAHARA K., SUZUKI T., NAKAMURA S.

Longitudinal changes in the skeletal pattern of deciduousanterior crossbite, Angle Orthod., 67, 6, 439-446, 1997;

49. PASNICU Letiia Elemente de genetic n Ortodonie, Ed.Corson, Iai, 2000;

50. PASNICU Letiia, FRATU V.A. Influena factorilor

genetici n anomaliile dento-maxilare clasa a III-a, Rev.Ortodonie i Ortopedie Dento-facial, 1, 22-25, 2001;

51. Paulo COZZA, MARINO Alessandra, MUCEDEROManuela An orthopaedic approach to the treatment of classIII malocclusions in the early mixed dentition, EuropeanJournal of Orthodontic, 26, 191-199, 2004;

52. POP E., CRLOGEA Valentina Prevalena anomaliilordento-maxilare la populaia infantil n vrst de 5-14 ani,Rev. Stomatologie, 4, 297-307, 1983;

53. PROFFIT W., FIELDS H.W. Contemporary orthodontics,Ed. C.W.Mosby Comp, St. Louis, Toronto, 1996;

54. RABIE A.B.M., HAGG U. Factors regulating mandibularcondylar growth, Am. J. Orthod., 122, 4, 401-409, 2002;

55. RABIE A.S.M., YAN G.U. Diagnostic criteria for pseudo-class III malocclusion, Am.J.Orthod.Dentofac.Orthop., 117,

1, 1-9, 2000;


68/69

67

56. RAKOSI Th., DONAS I., GRABER Th.M. Diagnosticorthodontique, Ed. G.Thieme, Stuttgard, 1993;

57. REICHENBACK E., BRUCKL H., KieferorthopadischeKlinik und Therapie, Leipzig, 1971;

58. SCNTEI VALENTINA Studiul longitudinal al creterii i

dezvoltrii faciale, Rev. Stomatologia, 3: 213-221, 1981;59. SCHWARZ M. Lehrgang der Gebissgelung, Viena, 1961;60. SINGH G. D., McNAMARA J.A., LOZANOFF S.

Mandibular morphology in subjects with class IIImalocclusion. Finit element morphometry, AngleOrthodontist, 68, 5, 467-471, 1998;

61. STANCIU Drago, DOROB Valentina Ortodonie i

Ortopedie Dento-Facial, Ed. Medical, Bucureti, 2003;62. STANCIU Drago, DOROB Valentina Ortodonie, Ed.Medical, Bucureti, 1991;

63. STOCKFISCH H. The Principles and practice ofDentofacial orthopaedics, Quintessence Publishing Co.,Londra, 1995;

64. SUHTELNY J.D. Early Orthodontic Treatment, Ed.Quintessence Publishing Co. Inc., Chicago, 2003;

65. ERBNESCU Alin Posibiliti i limite de apreciere adeficitului de spaiu n anomaliile dento-maxilare, Ed.Ripoprint, Cluj-Napoca, 2001.

66. THOMPSON I.R. The individuality of the patient in facialskeletal growth, Am. I. O-DO, 105, 2: 117-127, 1994;

67. TULLEY W.I. A textbook of orthodontics, Ed. Wright,Londra, 1998;

68. TURLEY P.K. Orthopedic correction of class IIImalocclusions with palatal expansion and custom protractionheadgear, J.Clin.Orthod., 22, 314-325, 1998;

69. VACHER C., ONOLFO I.P., LEZY I.P., COPIN H. Lacroissance du maxillaire chez lhomme, Rev. Stomatol. Chir.Maxillofaciale, 102, 3-4: 143-153, 2001;

70. VALL- CUSSAC V. Variabilit du desequilibrearchitecturale au travrs dun echantion de class III

squeletique et dentaire, Orthopedie francaise, 65, 1, 437-453,1994;


69/69

71. VALL-CUSSAC V. Larhitecture cranio-faciale declasses III selon lanalyse de Coben, Orthopedie Francaise,62, III, 995-1019, 1991;

72. VERNESCU-LEHENI Victoria Unele aspecte aletratamentului ortodontic precoce, Stomatologie, 3, 243-248,

1965;73. VOINEA Corina Cristina, BIL Anca, GRIVU OV.

Funcia muscular i aparatul dento-maxilar, Ed. Mirton,Timioara, 1996;

74. WILLIAMS S., ANDERSEN C.E. The morphology of thepotential class III skeletal pattern in the young child, Am. J.Orthod., 89:302-11, 1986;

75. ZEGAN Georgeta Ortodonie i Ortopedie Dento-Facial,Ed. Tehnopress, Iai, 2005;

LISTA LUCRRILOR TIINIFICE PUBLICATE DINTEMATICA DOCTORATULUI

1. Ionela Teodora DASCLU (CUUI) Importana StudiuluiTeleradiografiei (Metoda Tweed) n Diagnosticul

Anomaliilor Dento-Maxilare Clasa A III-A Angle, RevistaRomn de Stomatologie, volumul LVI, nr. 1, pag. 44-47,2010;

2. Ionela Teodora DASCLU (CUUI) EtiopatogeniaAnomaliilor Dento-Maxilare Clasa A III-A Angle, RevistaRomn de Stomatologie, volumul LVI, nr. 1, pag. 48-50,2010.

Bacaan Rezumat_en_DASCALU_IONELA_TEODORA.pdf

Documents