Occlusal Consideration in Different Clinical Situation.pdf

Occlusal consideration in different clinical situations Dr Ali Abdulghani AlSourori  Occlusal scheme for implant supported prosthesis When mandibular implant-supported prosthesis opposes maxillary osseointegarted prosthesis or natural dentition: 1. Mutually protected occlusio...

Occlusal consideration in different clinical situations Dr Ali Abdulghani AlSourori  Occlusal scheme for implant supported prosthesis When mandibular implant-supported prosthesis opposes maxillary osseointegarted prosthesis or natural dentition: 1. Mutually protected occlusion. 2. Lingualized occlusion. 3. Medial positioned Lingualized occlusion. 4. Bilateral balanced occlusion. When mandibular implant-supported prosthesis opposes partially edentulous maxillary arch: Maxillary condition Mandibular condition Occlusal concept Balanced occlusion Kennedy class I Implant-supported C.D. Lingualized, and medial positioned lingualized occlusion Working side Kennedy class II Implant-supported C.D. contact (group function) Implant-supported C.D. Mutually Protected Kennedy class III occlusion /OR Group function.  Occlusal consideration for Maxillary single denture The Subsequent problems with single denture against natural teeth The firmness and rigidity in which the natural teeth are retained in the bone. The great magnitude of the force generated by remaining natural teeth. The occlusal form of the remaining natural teeth, which will dictate the occlusal form of the denture.  The fixed positions of the mandibular anterior teeth that make the esthetic and phonetic placement of the maxillary teeth difficult without introducing anterior interference in eccentric functional movements. Abrasion of the artificial teeth if acrylic is used or the abrasion of natural teeth if porcelain is used.  How To Overcome These Problems The primary consideration for a continued success of a single complete denture is the preservation of that which remains, Proper diagnosis and full use of every factor, which favor success for this denture, Applying the principles of c.d construction. Maximum base extension within functional anatomical limits (distributed forces over the largest possible area of supporting structures and the force per unit area kept at minimum). Reduction of the forces to which the denture is subject.  The occlusal plane of natural teeth must be adjusted to a reasonable level, and harmonious occlusion must be established to control the destructive forces Steps for Occlusal Adjustment: Maxillary and mandibular impressions are made and poured. the casts is mounted on a semi-adjustable articulator using provisional centric relation record at an acceptable vertical dimension. Eccentric records are made and the condylar elements of the articulator are set.  Tooth Modification: First Technique ( Swenson’s Technique ) Denture teeth are set and when the natural teeth interfere with placement of denture, stone teeth are adjusted and marked on the cast with pencil.The natural teeth are modified using the diagnostic cast as a guide.  Second Technique (Yurkstas) The use of a metal U-shaped occlusal template that is slightly convex on the lower surface is placed on the occlusal surfaces of the remaining teeth. A Third Technique Described by (Bruce) The Modifications Are Made on the Stone Cast. A Clear Acrylic Resin Template Is Fabricated Over the Modified Stone Cast. The inner surface of the template is coated with pressure indicating paste and placed over the natural teeth, interferences are noted and removed. Another Technique Explained by (Boucher et. Al) The interferences are removed by movement of the maxillary porcelain teeth over the mandibular stone teeth. Prematurities are identified and removed by grinding the natural teeth. The procedure is repeated until a harmonious balanced occlusion is established.  In maxillary single denture, harmonious balanced occlusion throughout the full range of mandibular excursions is important to stabilize the denture and to reduce the amount of horizontal forces acting on the denture.  Functional chew-in techniques 1. Stansbury technique: A compound maxillary rim are used and trimmed buccally and lingually so that the occlusion is free in lateral excursions. Carding wax is then added to the compound rim and the patient is instructed to perform eccentric chewing movements. The carding wax is slowly molded to the functional movements, while the compound in the central fossa acts as a guide to preserve the vertical dimension.  The generated occlusion rim is now removed from the mouth and stone is vibrated into the wax paths of the cusps. The upper cast is then fastened to the articulator with the generated occlusion rim and the stone cusp path record. The stone cusp path record is secured to the lower member of the articulator with plaster. The denture teeth are first set to the lower cast of the patient's teeth. After the esthetics have been approved at the try-in, the lower cast is removed and the lower chew-in cast record is then secured to the articulator. All interfering spots are carefully ground until the incisal guide pin prevents further closure. 2. Vig technique: He recommended the use of a resin fin placed into the central grooves of the lower posterior teeth. The resin fin maintains the vertical dimension and helps to diagnostically locate the interfering lower cusps. In eccentric movements the lower cusp tips are ground until equal contact occurs between the teeth and resin. The fin is then built up using soft wax (Tenex), and functional path is recorded. 3. Sharry technique: Using a maxillary rim of softened wax. Lateral and protrusive chewing movements are made so that the wax is abroaded, generating the functional paths of the lower cusps. This is continued until the correct'vertical dimension has been established. 4. Rudd technique: A compound maxillary rim is used and a thickness of recording matrix, made up of three sheets of medium-hard pink base plate wax and two sheets of red counter wax, is added to the buccal and lingual surfaces of the compound rim. He also suggested using two maxillary bases, one for recording the generated path and the other for setting the teeth, to reduce the number of appointments necessary for construction of the upper denture.  Occlusal scheme for removable partial denture Maxillary condition Mandibular condition Occlusal concept Fully edentulous Kennedy class I restored by R.P.D. -Balanced occlusion restored by C.D. working-balancing - protrusive. Fully dentate Kennedy class I restored by R.P.D. - Working side contact Kennedy class 1 - Working and balancing Fully dentate side contact Restored by R.P.D. Kennedy class 11. Fully dentate - Working side contact -Working side contact Kennedy class II Fully dentate. -Working side contact Class III Class III Fully dentate -Contact in centric No- Class IV eccentric contact. Thank you