Single complete denture part 1 Dr.Mohammed Al sayed 11/3/2008.

Single complete dentureSingle complete denturepart 1part 1

Dr.Mohammed Al sayed

11/3/2008

DefinitionDefinition::

A single complete denture is a A single complete denture is a complete denture that occludes complete denture that occludes against some or all of the natural against some or all of the natural teeth, a fixed restoration, or a teeth, a fixed restoration, or a previously constructed removable previously constructed removable partial denture or a complete partial denture or a complete denturedenture..

**Construction and delivery of Construction and delivery of single complete dentures is more single complete dentures is more complicated than the delivery of complicated than the delivery of upper and lower complete upper and lower complete dentures on a patientdentures on a patient..

There are four reasons for this increased difficultyThere are four reasons for this increased difficulty::

11..The ability of the patient to generate heavy The ability of the patient to generate heavy occlusal forces, due to the existence of opposing occlusal forces, due to the existence of opposing

natural teeth natural teeth . .

22..The unsuitability of the denture foundation tissues The unsuitability of the denture foundation tissues (mucosa) to resist high occlusal forces from the (mucosa) to resist high occlusal forces from the opposing natural teeth, which results in advanced opposing natural teeth, which results in advanced

bone loss of the residual alveolar ridges bone loss of the residual alveolar ridges . .

33..Supraeruption of the opposing natural teeth Supraeruption of the opposing natural teeth produces an unharmonious occlusal plane, and produces an unharmonious occlusal plane, and minimizes the vertical space for setting the minimizes the vertical space for setting the opposing denture teeth opposing denture teeth . .

44..Mesial drifting of the opposing natural teeth results in Mesial drifting of the opposing natural teeth results in an increased mesial axial angulation (tilting) which an increased mesial axial angulation (tilting) which produce an unharmonious occlusal plane produce an unharmonious occlusal plane

The dentist may be able to overcome the The dentist may be able to overcome the problems associated with the single problems associated with the single complete denture By Applying the complete denture By Applying the followingfollowing::

a. All fundamental steps in denture a. All fundamental steps in denture construction must be followed and construction must be followed and completed to perfection( without minor completed to perfection( without minor errors) errors)..

b.The occlusal plane of the natural teeth in b.The occlusal plane of the natural teeth in the opposing arch must be made the opposing arch must be made

harmonious harmonious . .

Maximizing the ability of the denture supporting tissue to withstand destructive occlusal forces:

11..The denture base borders should have the The denture base borders should have the maximum extension within the functional maximum extension within the functional anatomical limits. In this way the forces of anatomical limits. In this way the forces of occlusion will be distributed over the largest occlusion will be distributed over the largest possible area of the denture supporting possible area of the denture supporting tissuetissue..

Causes of occlusal problems and Causes of occlusal problems and fracture of denture basesfracture of denture bases::

11..Occlusal stress on the maxillary Occlusal stress on the maxillary denture and the underlying denture and the underlying edentulous tissues from the edentulous tissues from the

opposing natural dentitionopposing natural dentition . .

22..The position of the mandibular teeth, The position of the mandibular teeth, which may not be probably which may not be probably aligned to achieve bilateral balance aligned to achieve bilateral balance

for stability for stability . .

33..Flexure of the denture baseFlexure of the denture base . .

Single complete denture may be opposed by one of the following:

11..Natural teethNatural teeth..

22..Fixed restorationsFixed restorations

33..A removable partial dentureA removable partial denture..

44..An existing complete dentureAn existing complete denture..

1.Single complete denture opposed by natural teeth:

The most common complete denture is The most common complete denture is a complete upper denture and lower a complete upper denture and lower natural teethnatural teeth..

In evaluating the natural dentition the following should be checked:

1.Uneven alignment of teeth.

Example: Tipping and extrusion

2.Character of the occlusal surface.

Natural teeth often exhibit varying steepness of the cusps and/or associated abrasion and wear.

33..Cross-bite relationshipCross-bite relationship..

44..Number and position of the natural Number and position of the natural teethteeth..

The stability of the single upper denture The stability of the single upper denture during function is directly proportional during function is directly proportional to the number of posterior with which to the number of posterior with which it occludesit occludes..

Complicating factors for the single Complicating factors for the single mandibular complete denture opposing mandibular complete denture opposing natural teethnatural teeth::

11..The denture supporting tissues for the The denture supporting tissues for the mandibular complete denture is relatively mandibular complete denture is relatively small when compared to the maxillary small when compared to the maxillary supporting tissue supporting tissue..

22..The mucosa and submucosa overlying the The mucosa and submucosa overlying the periostium and bone of the lower residual periostium and bone of the lower residual

ridge is thin ridge is thin . .33..For the above two reasons, the underlying For the above two reasons, the underlying

bone is extremely prone to resorption bone is extremely prone to resorption from occlusal forces of the natural teeth from occlusal forces of the natural teeth . .

44..Solution:Solution: consider extraction the healthy consider extraction the healthy upper teeth, since the long term health of upper teeth, since the long term health of

the mouth is at stake the mouth is at stake . .

There are two situations When a There are two situations When a mandibular complete denture, opposing mandibular complete denture, opposing upper natural teeth are acceptedupper natural teeth are accepted::

11..When the patient has a class III jaw When the patient has a class III jaw relationship. This occur when the mandible relationship. This occur when the mandible is is largerlarger than normal or the maxilla is than normal or the maxilla is

smallersmaller than normal than normal . .

22..When the patient has a cleft palate, either with When the patient has a cleft palate, either with the cleft partially open or closed the cleft partially open or closed . .

Difficulties found with maxillomandibular Difficulties found with maxillomandibular jaw relations for the single maxillary jaw relations for the single maxillary denturedenture::

A. The finalized maxillary wax occlusal rim may not be A. The finalized maxillary wax occlusal rim may not be parallel to the ala - tragus line, since the parallel to the ala - tragus line, since the opposing occlusal surfaces of the mandibular opposing occlusal surfaces of the mandibular natural teeth will dictate the angulation of the natural teeth will dictate the angulation of the

occlusal planeocclusal plane . .

b. The labiolingual thickness of the anterior wax b. The labiolingual thickness of the anterior wax occlusal rim will interfere with establishing the occlusal rim will interfere with establishing the correct vertical dimension of occlusion, if the correct vertical dimension of occlusion, if the future anterior teeth arrangement will require future anterior teeth arrangement will require vertical overlap. (fig. A)vertical overlap. (fig. A)

c. Occlusal rim occlusion: The anterior-lingual c. Occlusal rim occlusion: The anterior-lingual portion of the maxillary anterior wax rim must be portion of the maxillary anterior wax rim must be made thin, in order to allow the lower incisors to made thin, in order to allow the lower incisors to produce the correct vertical overlap for produce the correct vertical overlap for establishing the correct vertical dimension of establishing the correct vertical dimension of occlusion, which will be less than the vertical occlusion, which will be less than the vertical dimension of rest. (fig. B)dimension of rest. (fig. B)

Occlusal modification requirements for the Occlusal modification requirements for the opposing mandibular natural /restored opposing mandibular natural /restored teethteeth::

11..Assess the occlusal plane. One method is to use an Assess the occlusal plane. One method is to use an occlusal template, in order to assess the relation occlusal template, in order to assess the relation of the occlusal surfaces of the teeth to the of the occlusal surfaces of the teeth to the occlusal templateocclusal template..

22..The occlusal surfaces of the natural teeth can be The occlusal surfaces of the natural teeth can be ground or restored to give a more suitable ground or restored to give a more suitable occlusal plane occlusal plane..

33..Grossly malpositioned teeth can be considered for Grossly malpositioned teeth can be considered for extraction or for orthodontic repositioning extraction or for orthodontic repositioning..

44..Occlusal modification are best experimentally Occlusal modification are best experimentally performed upon mounted diagnostic casts in performed upon mounted diagnostic casts in order to determine the feasibility of occlusal order to determine the feasibility of occlusal

grinding or for restorationsgrinding or for restorations . .

Occlusal adjustment-Perfecting the plane Occlusal adjustment-Perfecting the plane of occlusion:of occlusion: Two methodsTwo methods::

11stst method method::

a. Mount the maxillary edentulous cast and the a. Mount the maxillary edentulous cast and the mandibular cast on a semi-adjustable articulator mandibular cast on a semi-adjustable articulator using an arbitrary facebow and a centric relation using an arbitrary facebow and a centric relation record at the established vertical dimension of record at the established vertical dimension of occlusionocclusion..

b. Make a protrusive record and set the horizontal b. Make a protrusive record and set the horizontal condylar guidance ( condyle angle)condylar guidance ( condyle angle)..

c.Set the upper artificial teeth one by one on the c.Set the upper artificial teeth one by one on the denture base and adjust the lower occluding stone denture base and adjust the lower occluding stone teeth (by scraping) in order to establish a teeth (by scraping) in order to establish a harmonious occlusal plane. Mark the area of the harmonious occlusal plane. Mark the area of the

stone teeth that have been alteredstone teeth that have been altered . .

d. When a favorable occlusal plane and articulation of d. When a favorable occlusal plane and articulation of the teeth have been achieved, the occlusal the teeth have been achieved, the occlusal adjustment are then carried out on the natural adjustment are then carried out on the natural teeth in the mouth using the marked diagnostic teeth in the mouth using the marked diagnostic

cast and the trial denture set up as guides cast and the trial denture set up as guides . .

e. After the occlusal adjustment have been made in the e. After the occlusal adjustment have been made in the mouth ,a new impression of the natural teeth is mouth ,a new impression of the natural teeth is obtained, a new centric relation record is made, obtained, a new centric relation record is made, and the new lower cast is mounted on the semi- and the new lower cast is mounted on the semi- adjustable articulator adjustable articulator..

f. The maxillary artificial teeth are rearranged for f. The maxillary artificial teeth are rearranged for harmony in centric relation occlusion and in harmony in centric relation occlusion and in extrusive movement. The next clinical step is the extrusive movement. The next clinical step is the try in of the trial wax up maxillary complete try in of the trial wax up maxillary complete

denturedenture . .

22ndnd method method::

a. Use an occlusal metal template. The inferior surface a. Use an occlusal metal template. The inferior surface of the template is slightly convex. The ideal of the template is slightly convex. The ideal occlusal plane is established when all the incisal occlusal plane is established when all the incisal edge and occlusal cusps touch this metal edge and occlusal cusps touch this metal occlusal plane resulting in a slightly occlusal occlusal plane resulting in a slightly occlusal plane of the mandibular teeth plane of the mandibular teeth..

b. The metal template is placed on the incisal and b. The metal template is placed on the incisal and occlusal surfaces of the lower stone cast teeth occlusal surfaces of the lower stone cast teeth . .

Cusps and incisal edges which are too high or too Cusps and incisal edges which are too high or too law are identified law are identified..

c. The high stone cusps are reduced with sharp knife c. The high stone cusps are reduced with sharp knife until there is an even contact of all teeth to the until there is an even contact of all teeth to the curved occlusal plane template. Reduced areas curved occlusal plane template. Reduced areas on the stone teeth are marked on the cast by on the stone teeth are marked on the cast by

pencil pencil . .

d. The occlusal adjustment are then carried out on the d. The occlusal adjustment are then carried out on the natural teeth in the mouth, using the pencil natural teeth in the mouth, using the pencil marked diagnostic cast as a guide marked diagnostic cast as a guide..