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Removable Partial Denture Framework Adjustment. Rudd & Kuebker 75% of frameworks don ’ t fit perfectly Active - orthodontic movement Adjust to make passive. Framework Adjustment. Adjust without denture base Adjust soon after fabrication Prevent tooth migration.
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Removable Partial Denture Framework Adjustment • Rudd & Kuebker • 75% of frameworks don’t fit perfectly • Active - orthodontic movement • Adjust to make passive
Framework Adjustment • Adjust without denture base • Adjust soon after fabrication • Prevent tooth migration
Clinical Adjustment • Incomplete seating • Usually binding on abutments • Use an indicating medium Incomplete seating
Indicating Medium • Aerosol Sprays (Occlude) • Disclosing Wax • Silicone
Two-Dimensional Indicating Medium • Occlude (aerosol) • Thin & accurate • Not easily displaced • Can dissolve in saliva • Difficult to remove • Can’t tell how far from seating
Three-Dimensional Indicating Medium • Disclosing Wax • Sets immediately • Inexpensive • Shows how far from seating • Can stick to teeth • Can be distorted
Adjustment withSilicone Indicating Medium • Three dimensional • Minimal distortion • More expensive • Sets relatively slowly (~1-2 min) • Can tear or pull off the framework
Framework Adjustment • Initial Assessment • ‘How does the framework feel?’ • No pulling or wedging • Active engagement of abutment teeth • Overall comfort of the framework
Framework Adjustment • Areas of abrasion on master cast may indicate areas of binding
Check Maxillary Beading • Ensure not binding on bony midline • Can cause entire framework not to seat • Use PIP to check • Will burn through if excessive height Beading
Cautious Adjustment • Differentiate between normal & abnormal contacts • Guiding planes • normal: long vertical areas of contact • broad areas of severe burn-through may indicate binding
Cautious Adjustment • Avoid excessive force - bending • Heat generation could melt acrylic • Retentive tip of direct retainers • normal: burn-through • eliminate active clasp retention
Remake Poor Castings • Determine if casting fits similarly on the cast and intraorally • If not, final impression inaccurate • Make new impression
Framework Occlusal Adjustments • Fabricated on unmounted casts • Occlusal interferences usually present • Occlusal vertical dimension should be unchanged • Centric & eccentric contacts should be identical with or without framework
Framework Occlusal Adjustments • Highly polished metal • Articulating paper marks poorly • Check opposing occlusal contacts • Slightly roughen framework with air abrasive or rubber impregnated abrasive
Opposing Frameworks • Adjust individually • Then adjust together • Eliminate interferences between the frameworks
Occlusal Rest Thickness • If ≤ 1.5 mm after adjustment • Subject to fatigue • Possible fracture • May require additional tooth preparation & remake • Last resort - occlusal reduction of opposing teeth
Interferences on Retentive Arms • Minor interference • Reduce opposing cusp - last resort • Heavy contact • Lower height of contour, remake • Don’t relieve • Alters flexibility & fracture resistance
Physiologic Relief • Used for Class I & II w. long g.p. • Normally shorter guiding planes • Triangular space below height of contour • Allow for release • Tipped teeth may only provide for long guiding planes (low h of c)
Physiologic Relief • Distal Extension Cases • Guiding planes, minor connectors & lingual plates coated with indicator • Framework is placed in hyperfunction by pressing over gridwork
Physiologic Relief • Relieve burn-through • Until burn-through occurs only on the occlusal one third of the guiding planes
Physiologic Relief Alternative • Prescribe 1° relief OR • Use physiologic relief, not both