24-Sequelae of Wearing Complete Dentures - Rajat Dang

By, Dr. Rajat Dang SEQUELAE CAUSED BY WEARING COMPLETE DENTURES THE DENTURE IN THE ORAL ENVIRONMENT

Placement of a removable prosthesis in the oral cavity produces

profound changes of the oral environment that may have an adverse effect

on the integrity of the oral tissues .Mucosal reactions could result from a

mechanical irritation by the dentures, an accumulation of microbial plaque

on the dentures, or occasionally, a toxic or allergic reaction to constituents

of the denture material. The continuous wearing of dentures may have a

negative effect on residual ridge form because of bone resorption.

Direct Sequelae Caused by Wearing Removable Prostheses: Complete or Partial Dentures

• Mucosal reactions

• Oral galvanic currents

• Altered taste perception

• Burning mouth syndrome

• Gagging

• Residual ridge reduction

• Periodontal disease (abutments)

• Caries (abutments)

Furthermore, wearing complete dentures that function poorly and that

impair masticatory function could be a negative factor with regard to

maintenance of adequate muscle function and nutritional status,

particularly in older persons.There are several aspects of the interaction

between the prosthesis and the oral environment.Surface properties of the

prosthetic material may affect plaque formation on the prosthesis; however

the original surface chemistry of the prosthetic material is modified by the

acquired pellicle and thus is of minor importance for the establishment of

plaque .

On the contrary, surface irregularities or microporosities greatly promote

plaque accumulation by enhancing the surface area exposed to microbial

colonization and by enhancing the attachment of plaque. Furthermore,

plaque formation is greatly influenced by environmental conditions such as

the design of the prosthesis, health of adjacentmucosa, composition of

saliva, salivary secretion rate, oral hygiene, and denture-wearing habits of

the patient.

The presence of different types of dental materials in the oral cavity

may give rise to electrochemical corrosion, but changes in the oral

environment due to bacterial plaque may constitute an important cofactor

in this process. Corrosive galvanic currents have been implicated in the

burning mouth syndrome (BMS), oral lichen planus, and altered taste

perception. Most often it is difficult to establish a definite causal

relationship because mechanical irritation or infection may also be

involved. For instance, local irritation of the mucosa by the dentures may

increase mucosal permeability to allergens or microbial antigens.

This makes it difficult to distinguish between a simple irritation and an

allergic reaction against the prosthetic material, microbial antigens, or

agents absorbed to the prosthesis capable of eliciting an allergic response.

The matter is further complicated by the fact that certain microorganisms

(e.g., yeasts) are able to use methylmethacrylate as a carbon source,

thereby causing a chemical degradation of the denture resin.

DIRECT SEQUELAE CAUSED BY WEARING DENTURES Denture Stomatitis

The pathological reactions of the denture-bearing palatal mucosa

appear under several titles and terms such as denture-induced stomatitis.

denture sore mouth. denture stomatitis, inflammatory papillary hyperplasia,

and chronic atrophic candidosis. In the following sections, the term denture

stomatitis will be used with the prefix Candida-associated if the yeast

Candida is involved. In the randomized populations, the prevalence of

denture stomatitis is about 50% among complete denture wearer.

Classification According to Newton's classification, three types of

denture stomatitis can be distinguished.

Type I A localized simple inflammation or pinpoint hyperemia.

Type II An erythematous or generalized simple type seen as more diffuse

erythema involving a part or the entire denture-covered mucosa.

Type III A granular type (inflammatory papillary hyperplasia) commonly

involving the central part of the hard palate and the alveolar ridges.

Type III often is seen in association with Type I or Type II Strains of the

genus Candida, in particular Candida albicans, may cause denture

stomatitis. Still, this condition is not a specific disease entity because other

causal factors exist such as bacterial infection, mechanical irritation, or

allergy. Type I most often is trauma induced, whereas types II andIII most

often are caused by the presence of microbial plaque accumulation on

fitting denture surface

Factors Predisposing to Candida-Associated Denture Stomatitis

Systemic Factors Old age

Diabetes mellitus

Nutritional deficiencies (iron, folate, or vitaminB12

Malignancies (acute leukemia, agranulocytosis)

Immune defects

Corticosteroids, immunosuppressive drugs

Local Factors Dentures (changes in environmental conditions, trauma, denture usage,

denture cleanliness)

Xerostomia (Sjogren's syndrome, irradiation,drug therapy)

High-carbohydrate diet

Broad-spectrum antibiotics

Smoking tobacco

Management and Preventive Measures Because of the diverse possible origins of denture stomatitis, several

treatment procedures could be used, including antifungal therapy,

correction of ill-fitting dentures, and efficient plaque control. The patient

should be instructed to remove the dentures after the meal and scrub them

vigorously with soap before reinserting them. The mucosa in contact with

the denture should be kept clean and massaged with a soft toothbrush.

Patients with recurrent infections should be persuaded not to use

their dentures at night but rather leave them exposed to air, which seems

to be a safe and efficient means of preventing microbial colonization..

Rough areas on the fitting surface should be smoothed or relined with a

soft tissue conditioner. About 1 mm of the internal surface being

penetrated by microorganisms should be removed and relined frequently.

A new denture should be provided only when the mucosa has healed and

the patient is able to achieve good denture hygiene.

Local therapy with nystatin, amphotericin B, miconazole, or

clotrinlazole should be preferred to systemic therapy with ketoconazole or

fluconazole because resistance of Candida species to the latter drugs

occurs regularly. For a reduction in the risk of relapse, the following

precautions should be taken

1. Treatment with antifungals should continue for 4 weeks

2. When lozenges are prescribed, the patient should be instructed to

take out the dentures during sucking.

3. The patient should be instructed in meticulous oral and denture hygiene;

the patient should be told to wear the dentures as seldom as possible and

to keep them dry or in a disinfectant solution of 0.2% to 2.0% chlorhexidine

during nights

Flabby Ridge (i.e., mobile or extremely resilient alveolar ridge) is due to

replacement of bone by fibrous tissue. It is seen most commonly in the

anterior part of the maxilla, particularly when there are remaining anterior

teeth in the mandible, and is probably a sequela of excessive load of the

residual ridge and unstable occlusal conditions .Results of histological and

histochemical studies have shown marked fibrosis, inflammation, and

resorption of the underlying bone.

However, in a situation with extreme atrophy of the maxillary alveolar

ridge, flabby ridges should not be totally removed because the vestibular

area would be eliminated. Indeed the resilient ridge may provide some

retention for the denture.

REDUNDANT TISSUE The forces of the mandibular teeth on the maxilla cause an

excessive resorption of the anterior aspect of the maxilla and the

mandibular teeth supererupt. The tissue in this region becomes

hyperplastic and may form an epulis fissuratum in the anterior maxillary

fold. As the anterior aspect of the maxilla resorbs, there is a concurrent

resorption of bone under the mandibular partial denture base. The occlusal

plane drops posteriorly and rises anteriorly.

Denture Irritation Hyperplasia

A common sequela of wearing ill-fitting dentures is the occurrence of

tissue hyperplasia of the mucosa in contact with the denture border. The

lesions are the result of chronic injury by unstable dentures or by thin,

overextended denture flanges. The proliferation of tissue may take place

relatively quickly after placement of new dentures and is normally not

associated with marked symptoms. The lesions may be single or quite

numerous and are composed of flaps of hyperplastic connective tissue.

If lymphadenopathy is present, the denture irritation hyperplasia may

simulate a neoplastic process

HYPERPLASTIC TISSUE.

Often hyperplastic tissue is present under an ill filling denture which

may be hyperplasia or hyper plastic folds under the denture base .

When this situation occurs the patient should be instructed to rest

the tissue by not wearing the denture. Proper oral hygiene and tissue

massage will also improve the condition. The existing denture should be

refitted with a tissue or temporary reline material. If marked improvement

does not occur surgical correction will be needed.

PAPILLARY HYPERPLASIA

Papillary hyperplasia develops in the palatal vault as multiple

papillary projections of the epithelium in response to local irritation, poor

oral hygiene, and low-grade infections such as Monilia. The polypoid

masses are usually intensely red, soft, and freely movable.Histologically,

the surface epithelium is hyperplastic with fibrous hyperplasia and in-

flammatory cell infiltration of the underlying connective tissue. Biopsy

usually confirms papillary hyperplasia, but some specimens show

pseudoepitheliomatous hyperplasia or dyskeratosis of the surface

epithelium.

Traumatic Ulcers Traumatic ulcers or sore spots most commonly develop within 1 to 2

days after placement of new dentures. The ulcers are small and painful

lesions, covered by a gray necrotic membrane and surrounded by an

inflammatory halo with fine, elevated borders .The direct cause is usually

overextended denture flanges or unbalanced occlusion. Conditions that

suppress resistance of the mucosa to mechanical irritation are

predisposing (e.g., diabetes mellitus, nutritional deficiencies, radiation

therapy, or xerostomia). In the systemically noncompromised host, sore

spots will heal a few days after correction of the dentures.

Oral Cancer in Denture Wearers An association between oral carcinoma and chronic irritation of the

mucosa by the dentures has often been claimed, but no definite proof

seems to exist .Case reports have detailed the development of oral

carcinomas in patients who wear illfitting dentures. However, most oral

cancers do develop in partially or totally edentulous patients. The reasons

appear to include an association withmore heavy alcohol and tobacco use,

less education, and lower socioeconomic status, which predispose to oral

cancer as well as to poor dental health, including tooth extraction and

denture wearing.

This underlines the necessity of strict and regular recall visits at 6-

month to 1-year intervals for comprehensive oral examinations. The

opinion is still valid that if a sore spot does not heal after correction of the

denture, malignancy should be suspected. Patients with such cases and

clinically aberrant manifestations of denture irritation hyperplasia should be

referred immediately to a pathologist. It should be recognized that the

prognosis is poor for oral carcinoma,especially for those in the floor of the

mouth.

Guggenheimer et al (1994) studied and concluded that majority of

oral cancers are likely to develop in partially or total edentulous patient.It

has been shown that periodic oral examination can detect these tumour

earlier than when patient return only because of symptoms which will result

in unfavorable prognosis.Dentist should encourage partially and toatally

edentulous patient to return for recall visit at 6 month or 1 year. These

could reveal larger proportion of localized malignancies and premalignant

lesion as well.It is no less important to recall edentulous paatient regularly

to asses their oral tissues for the presence of disease than to recall

dentate persons for evaluation of their dentate and periodontal health.

BURNING MOUTH SYNDROME BMS could be a sequalae of denture wearing and is characterized by a

burning sensation in one or several oral structures in contact with the den-

tures. It is relevant to differentiate between burning mouth sensations and

BMS. In the former group, the patient's oral mucosae are often inflamed

because of mechanical irritation, infection, or an allergic reaction. In

patients with BMS, the oral mucosa usually appears clinically healthy. The

vast majority of those patients affected by BMS is older than 50 years of

age, is female, and wears complete dentures.

A vague burning sensation or pain under an apparently well-fitting

denture with the complete absence of any detectable lesions is a common

complaint of the geriatric patient. A burning tongue is also frequently

brought to the attention of the dentist. These symptoms may be associated

with complete or partial dentures but are sometimes experienced when no

prosthetic replacements are in use. If dentures are used, simply requesting

the patient to leave them out for a period of time to see if the sensation dis-

appears will determine whether they are at fault. Determining the exact

etiology and treatment is often difficult and may require the cooperation of

the patient's physician and possibly psychiatric.

Burning Mouth Syndrome

Local Factors Mechanical irritation

Allergy Infection

Oral habits and parafunctions

Myofascial pain

Systemic Factors Vitamin deficiency

Iron deficiency anemia Xerostomia

Menopause

Diabetes

Parkinson's disease

Medication

Psychogenic Factors Depression

Anxiety

Psychosocial stressors

Management

In denture wearers in whom no organic basis for the complaints is

identified, the approach of the prosthodontist should be very careful. The

situation may be further complicated by the fact that the patients often

claim that their psychiatric disorders are due to the poor dentures and the

inadequate prosthetic treatment they have received. The patient's

symptoms should always be taken seriously, but any comprehensive

prosthetic treatment, including treatment with implant-supported

overdentures, should be carried out only as a collaborative effort of

psychiatrist and prosthodontist.

Gagging The gag reflex is a normal, healthy defense mechanism. Its

function is to prevent foreign bodies from entering the trachea. Gagging

can be triggered by tactile stimulation of the soft palate, the posterior part

of the tongue, and the fauces. In sensitive patients, the gag reflex is easily

released after placement of new dentures, but it usually disappears in a

few days as the patient adapts to the dentures. Persistent complaints of

gagging may be due to overextended borders (especially the posterior part

of the maxillary denture and the distolingual part of the mandibular

denture) or poor retention of the maxillary denture.

However, the condition is often due to unstable occlusal conditions

or increased vertical dimension of occlusion because the unbalanced or

frequent occlusal contacts may prevent adaptation and trigger gagging

reflexes.

Patients who develop a gagging or vomiting problem with dentures

are frequently difficult to treat, and the difficulty is primarily one of

determining the cause. Some patients have a hypersensitive gagging

reflex evident prior to and during the denture construction. The insertion or

removal of complete dentures may elicit gagging. However, occasionally a

patient develops a gagging problem after denture insertion.

Residual Ridge Reduction

Longitudinal studies of the form and weight of the edentulous

residual ridge in wearers of complete dentures have demonstrated a

continuous loss of bone tissue after tooth extraction and placement of

complete dentures. The reduction is a sequel of alveolar remodeling due to

altered functional stimulus of the bone tissue. The process of remodeling is

particularly important in areas with thin cortical bone (e.g., the buccal and

labial parts of the maxilla and the lingual parts of the mandible). During the

first year after tooth extraction, the reduction of the residual ridge height in

the midsagittal plane is about 2 to 3 mm for the maxilla and 4 to 5 mm for

the mandible.

Jahangiri et al (1998) describes the clinical feature of residual ridges.

• Continuous size reduction of the residual ridge, largely due to bone loss

after tooth extraction.

• General feature: RRR is chronic progressive ,and irreversible.

• The rate is fastest in first six month of extraction.

• Rate is variable between different persons ,within the same person at

different times, within same person at different sites.

• Has a multifactorial cause

• Anatomic factor, prosthetic factor, metabolic and systemic factor,

fundamental factor.

Some Proposed Etiological Factors of Reduction of Residual Ridges Anatomical Factors 1. More important in the mandible versus the maxilla

2. Short and square face associated with elevated masticatory forces

3. Alveoloplasty

Prosthodontic Factors Intensive denture wearing

Unstable occlusal conditions

Immediate denture treatment

Metabolic and Systemic Factors Osteoporosis .

Calcium and vitamin D supplements for possible bone preservation

Overdenture Abutments: Caries and Periodontal Disease

The retention of selected teeth to serve as abutments under

complete dentures is an excellent prosthodontic technique. In this simple

method, a few teeth in a strategically good position are preserved and are

treated endodontically before the crown is modified. The exposed root

surface and canal are filled with amalgam or a composite restoration. In

this way, even periodontally affected teeth can be maintained for several

years in a relatively simple way.Overdenture treatment does not

necessarily increase the risk of technical failures such as denture fractures

or loss of denture teeth.

However, the wearing of overdentures is often associated with a

high risk of caries and progression of periodontal disease of the abutment

teeth. One of the reasons for this is that the bacterial colonization beneath

a close-fitting denture is enhanced, and good plaque control of the fitting

denture surface is generally difficult to obtain. One reason is that the

species of Streptococcus and Actinomyces predominating in denture

plaque are well known for their major contributions to dental plaque on

smooth enamel surfaces, as well as on root cementum.. This could explain

why it is difficult to maintain healthy periodontal conditions adjacent to

overdenture abutments.

Use of the fluoride-chlorhexidine gel controlled caries development

and maintained healthy periodontal conditions.The introduction of

adequate denture-wearing habits (e.g., to abstain from wearing the denture

during the night) is another efficient way to control caries and development

of periodontal disease in overdenture wearers.Treatment of superficial

caries of the overdenture abutments includes application of fluoride-

chlorhexidine gel and polishing, and not exclusive placement of fillings,

which could result in recurrent caries.

INDIRECT SEQUELAE Atrophy of Masticatory Muscles

It is essential that the oral function in complete denture wearers is

maintained throughout life. The masticatory function depends on the

skeletal muscular force and the facility with which the patient is able to

coordinate oral functional movements during mastication. Maximal bite

forces tend to decrease in older patients. Furthermore, computed

tomography studies of the masseter and the medial pterygoid muscles

have demonstrated a greater atrophy in complete-denture wearers,

particularly in women.

Indeed, elderly denture wearers often find that their chewing ability is

insufficient and that they are obliged to eat soft foods.

Diagnosis : Direct measurement of the capacity to reduce test food to small

particles has verified that chewing efficiency decreases as the number of

natural teeth is reduced and is worse for subjects wearing complete

dentures. One of the consequences is that wearers of conventional

complete dentures need approximately seven times more chewing strokes

than subjects with a natural dentition to achieve an equivalent reduction in

particle size. As a consequence, completedenture wearers prefer food that

is easy to chew, or they swallow large food particles.

Preventive Measures and Management To some extent, the retention of a small number of teeth used as

overdenture abutments seems to play an important role in the

maintenance of oral function in elderly denture wearers. Therefore

treatment with overdentures has particular relevance in view of the

increasing numbers of older people who are retaining a part of their natural

dentition later in life.In the completely edentulous patients, placement of

implants is usually followed by an improvement of the masticatory function

and an increase of maximal occlusal forces. There is is no evidence of a

similar benefit after a preprosthetic surgical intervention to improve the

anatomical conditions for wearing complete dentures.

Nutritional Deficiencies Epidemiology

Aging is often associated with a significant decrease in energy

needs as a consequence of a decline in muscle mass and decreased

physical activity. Thus a 30% reduction in energy needs should be and

usually is accompanied by a 30% reduction of food intake. However, with

the exception of carbohydrates, the requirement for virtually all other

nutrients does not decline significantly with age. As a consequence, the

dietary intake by elderly individuals frequently reveals evidence of

deficiencies, which is clearly related to the dental or prosthetic status.

Masticatory Ability and Performance One of the strong indications for prosthodontic treatment is to

improve masticatory function. In this context, the term masticatory ability is

used for an individual's own assessment of his or her masticatory function,

whereas efficiency is to be understood as the capacity to reduce food

during mastication. There is no striking evidence that malnutrition could be

a direct sequelae of wearing dentures. However, edentulous women have

a higher intake of fat and a higher consumption of coffee and a lower

intake of ascorbic acid compared with dentate subjects within the same

age group.

Nutritional Status and Masticatory Function

Four factors are related to dietary selection and the nutritional status

of wearers of complete dentures: masticatory function and oral health,

general health, socioeconomic status, and dietary habits. In healthy

individuals there is no evidence that the nutritional intake is impaired in

wearers of complete dentures or that replacement of ill-fitting dentures with

well-fitting new dentures will causea major improvement . Also, reduced

salivary secretion rate during mastication has a negative effect on

masticatory ability and efficiency

CONTROL OF SEQUELAE WITH THE USE OF COMPLETE DENTURES

The essential consequences of wearing complete dentures are

reduction of the residual ridges and pathological changes of the oral

mucosa. This often results in poor patient comfort, destabilization of the

occlusion, insufficient masticatory function, and esthetic problems.

Ultimately, the patient may not be able to wear dentures and will receive a

diagnosis of prosthetically maladaptive.

For the adverse sequelae of residual ridge resorption to be reduced, the

following should be considered:

1. Restoration of the partially edentulous patient with complete dentures

should be considered if this is the only alternative as a result of poor

periodontal health, unfavorable location of the remaining teeth, and

economic limitations. In this situation, every effort should be made to

retain some teeth in strategically good positions to serve as

overdenture abutments. The maintenance of tooth roots in the mandible

is particularly important.

2. The patient with complete dentures should follow a regular control

schedule at yearly intervals so that an acceptable fit and stable occlusal

condition can be maintained.

Edentulous patients should be aware of the benefits of an implant-

supported prosthesis in young patients; the primary advantage would be

reduced residual ridge reduction. In elderly patients, the main advantages

are improved comfort and maintenance of masticatory function.

The following precautions should be taken to preclude development of

soft tissue disease:

1. Patients wearing overdentures supported by natural roots or implants

should follow a program of recall and maintenance for continuous

monitoring of the denture and the oral tissues. If patient compliance is

difficult to obtain, this might indicate that it is necessary to see the

patient every3to4months.

2. The patient should be motivated to practice proper denture wearing

habits such as not wearing dentures during the night. Finally, it is

important to remind and to explain to our patients that treatment with

complete dentures is not a "definitive" treatment and that their collaboration

is important to prevent the long-term risks associated with the

consequences of wearing comlete dentures.