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Philosophies of Occlusion for Implants. Implant Occlusion. Single Crown Fixed Partial Dentures Full arch prostheses (screw retained) Overdentures. M any Philosophies of Occlusion. No definitive scientific studies to prove: one type of tooth form one type of occlusal scheme
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Implant Occlusion • Single Crown • Fixed Partial Dentures • Full arch prostheses (screw retained) • Overdentures
ManyPhilosophies of Occlusion Nodefinitivescientificstudies to prove: • one type of tooth form • one type of occlusal scheme • to be clearly preferred by patients • to be more efficient than another
Anatomic Non Anatomic Canine Guidance (Mutually Protected) Group Function Lingualized (Balanced) Monoplane Tooth Forms Occlusal Schemes
Occlusion & Implants • Evidence Based Review Taylor, Wiens et al. J Prosthet Dent 2005;94:555-560 • No Preferred occlusal scheme • Clinicians advocate axial loading of implants, but no evidence, at present, demonstrating benefits
Occlusion & Implants • Evidence Based Review Taylor, Wiens et al. J Prosthet Dent 2005;94:555-560 • No evidence at present that • progressive occlusal loading of implant is beneficial • occlusal overload is detrimental to implants
Absence of Scientific Evidence Not proof against! Follow best available clinical principles Do not build in heavy non-axial loading or overloading
Clinical Principles for Occlusion Based on Clinical Experience Not Scientific Evidence
General Principles Improve denture stability or axial loading of single teeth • Centric contacts on flat surfaces, not inclines
General Principles Posterior Overjet to Avoid Cheek Biting
General Principles Improve denture stability or single tooth loading • Center occlusal contacts over ridge • Simultaneous posterior contacts in centric
General Occlusal Principles For overdentures or full arch prostheses opposing a CD: • No anterior contacts in centric • Minimizes anterior resorption • Grazing anterior contacts in excursions • Incising
Occlusal Schemes • Canine Guidance • Group Function • Lingualized • Monoplane Single Teeth FPD’s Dentures
Crowns or FPD’s • Either canine guidance or group function works - no preference • Use what the patient has • Use what would be easiest
Overdentures or Full Arch Prostheses ALL Occlusal Schemes Devised to Maximize Denture Stability
Lingualized Occlusion • Maxillary cusped tooth • Mandibular cuspless or shallow cusped tooth • Maxillary lingual cusp balanceslike a mortar in a pestle
Lingualized Occlusion • Lingual cusp contacts opposing central fossae • Mandibular cuspal inclines are shallow (0°, 10°) • Less lateral displacement
Lingualized OcclusionHow Stability is Improved • Simultaneous bilateral anterior and posterior in all excursions • Tilting forces theoretically neutralized
Enter Bolus Exit Balance? • Many patients chew bilaterally • Biting forces maximum close to intercuspation (where balance most effective) • Non-functional aspects (swallow)
L M D B C Point of Loading Affects Stability • Browning, 1986 • Loaded centrally, M, D, L,B • B caused unseating • Central loading better than distal loading
Lingualized Contacts • Only buccal cusp contact is inner incline of mandibular teeth (balancing) Working Side Balancing Side
‘IIF’ Rule • IIF you have contacts on the Inner Inclines of Functional cusps they are balancing contacts
Rules for Balancing Contacts • Balancing contacts should be lines, not points • Balancing contacts should never be heavier than working contacts
Balanced Occlusion (Lingualized) • Indirect evidence that balanced occlusion may: • reduce ridge resorption (Maeda & Wood, 1989) • allow for increased functional forces in excursions (Miralles et al, 1989)
Lingualized Cusp Angles • Always use steep cusped maxillary tooth (33°) • When condylar guidance is steeper use more cusp angle in mandible (10°)
Lingualized Occlusion • Balance cannot be set without an articulator • Clinical remount on an articulator - fewer adjustments
Condylar Inclination • Posterior teeth separate as working condyle moves forward (and downward) • Anterior teeth contact • Closer to condyle, more separation • More anterior separation of Premolars if steep anterior guidance
Maintaining Balancing Contacts • Change occlusal plane angle • Increase compensating curves • Increase cusp angles or effective cusp angles
Checking for Balance Feels Smoooooothin excursions • - Fingers on max. canines • - Check on articulator
Assess Contacts: • Centric Stops • Excursions
Improving Denture Occlusion • Most important cusp - maxillary lingual • Mandibular buccal cusps more lateral - more tipping
When Not to Balance • Difficulty in obtaining repeatable centric record • incoordination, • muscle splinting • Dramatic malocclusions • Severe ridge resorption • lateral forces displace the denture • Implants tend to negate this factor
Monoplane Occlusion • Cuspless teeth set on a flat plane with 1.5- 2 mm overjet • No cusp to fossa relationship • No anterior contacts present in centric position • No overbite
Monoplane OcclusionHow Stability is Improved • Elimination of cusps • Lateral forces reduced, improving stability • Simplifies denture tooth arrangement
Ensure Teeth Set Over Ridge • Minimize tilting/tipping • Maximize stability • Minimize contacts on buccal of flat cusps
Monoplane Occlusion • Functional, but unesthetic • Not balanced - flat • Zero degree teeth can be balanced if condylar inclinations are shallow
Monoplane Occlussion - When? • Jaw size discrepancies, malocclusions • cross-bite, Cl II, III • Minimal ridge • reduces horizontal forces • implants help • Uncoordinated jaw movements
Summary No definitive studies to show one type of occlusion is best Follow established clinical principles Assess each case - adapt to clinical situation Continue to read the literature