Onlays and Inlays PDF - Summer 2024

Candice Johnson DDS Summer 2024 INLAY – Intracoronal indirect ONLAY – partial extracoronal restoration not involving indirect restoration involving cuspal coverage one or more cuspal coverage Similar to a direct restoration with the exception that all walls are divergent....

Candice Johnson DDS Summer 2024 INLAY – Intracoronal indirect ONLAY – partial extracoronal restoration not involving indirect restoration involving cuspal coverage one or more cuspal coverage Similar to a direct restoration with the exception that all walls are divergent. Indicated for an extensive preparation that require strength greater than a composite or amalgam restoration but does not require cuspal coverage. › Conservative – Gold/metallic onlays: compromised teeth in high stress areas – Ceramic: indicated for large restorative defect in low stress areas and esthetics are involved. › Improved esthetics › Cover and Reinforce cusps without removal of healthy tooth structure in the cervical and middle areas. › Supragingival margins – Easier for patients to maintain  Removal of caries or defect. Initial preparation is similar to direct restoration. Cavosurface margins are beveled including the proximal box  All walls are divergent  Occlusal dovetail is placed if mesial or distal proximal box is not prepared.  Secondary flaring of the proximal facial and lingual cavosurfaces joins the gingival bevel uninterrupted. Gingival cavosurface is beveled: Removes weakened enamel. Provides a sliding fit of the restoration Bevels with gingival 30 degrees is burnishable in the lab.  Similar to the inlay but with one or more cuspal coverage. Occlusal reduction of nonfunctional cusps is 0.75-1.0 mm with minimal extension onto the axial wall. Functional cusps are reduced 1.5 mm Shoulder following the lingual or facial axial walls of the cusp has a depth of 0.8 mm and occlusogingival height of 2.0-3.0 mm.  Nonfunctional cusps are “shoed” and follows the contour of the cusp tip and ridges. Functional cusps are reduced 1.5 mm Shoulder following the cusp › Unlike amalgam or cast gold preparations, undermined enamel does not have to be removed if confined to dentin. – Can be blocked out with glass ionomer prior to final preparation and impression. – Or can be blocked out by the laboratory and then filled and bonded with the composite resin luting agent. Crispin 1994 Conservative as much as possible Compromised tooth is only removed Convenience access is provided for the restoration. Affected dentin should be evaluated. Dentin discolored by caries or amalgam may need to be removed if esthetics is a consideration Or covered by an opaquer. Rounded internal line and point angles. Flat ended diamonds work well define internal line angles. Isthmus width: 1.5 – 2.0 mm Pulpal floor can vary according the planned restored anatomy. Should be 1.5-2.0 mm for adequate bulk for fabrication. Does not need to be flat or perpendicular to the long axis of the tooth. Fossa areas, especially the central fossa may need to be deeper to accommodate a deeper depth of the restoration. Proximal extensions are determined by extent of caries or previous restoration. For minimal preparations, equivalent amounts of the buccal and lingual wall are reduced and diverged. For larger preparations, excessive tooth removal should be at the expense of the nonfunctional cusp, thus preserving tooth structure next to the functional cusp. Gingival floor depth (cavosurface to axial wall) should be 1.0-1.5 mm. Should be maintained in enamel whenever possible. Cuspal Protection or Replacement: Extensions of the coverage is a clinical judgement but factors to be considered are: 1. Amount of enamel 2. Occlusal forces 3. Size of functional contact 4. Esthetics 5. Mesial-distal width of affected area Does your proximal extension wrap around toward the lingual or buccal to decrease strength of the cusp? Cuspal reduction for bulk of restorations is: Functional cusp: 2.0 – 2.5 mm Nonfunction cusp: 1.5 – 2.0 mm  Functional Cusps: Capped with a butt joint shoulder Gingival extension beyond contact point Non-functional Cusps: Shoed just beyond the tip and ridge of the cusp. Away from occlusal contact In both capping and shoeing, the margins should follow the contour of the cusp tip and Crispin 1994 ridges.  Finish line should NOT be beveled. There 2 schools of thought for the finish line. 1. A well defined, smooth butt joint (shoulder) Flat and smooth Proximal boxes should have flat floor over deep chamfer due to location near CEJ and need to retain enamel margin. 2. A hollow-ground chamfer (deep chamfer, or modified butt joint) Confined to enamel Better blending of the restoration with tooth structure. Axial wall should be divergent, more than what is required of a gold restoration. Due to retention by adhesion, walls do not need to be parallel. Increased taper, without unnecessary removal of tooth structure, allows for easier placement and removal when trying the restoration in. Increased taper also allows for more surface area for bonding for retention. After final impression, the preparation(s) need to be temporized to avoid shifting of the teeth and sensitivity. Indirectly using a preoperative matrix, poured model, temporary fabrication with cementation using a non-eugenol temporary cement. Directly with composite with NO etching or bonding Light cured temporary resin material  1. Proximal contact(s): If the restoration does seat easily, DO NOT force it into place. › Check for residual provisional material › Check with unwaxed floss › Adjust as needed and polish. › Check for any interproximal overhangs. 2. Marginal integrity: Once fully seated, check margins › A sharp explorer should travel from restoration to tooth structure, and vice versa, smoothly and without Crispin 1994 any catching. 3. Color is dependent on: Shade selection Opacity versus translucency of the ceramic restoration. Opacity versus translucency of the resin luting cement. Due to the air refraction space – try-in should have a light transmitting medium like glycerine, water, or try-in paste. 4. Occlusal contacts should be checked AFTER the restoration has been seated. There is a high risk of restoration fracture if the occlusion is checked prior to cementing. Centric and excursive contacts should be checked and adjusted as needed. Bonding of the ceramic restoration involves a series of individual links. Tooth interface: etched enamel micro mechanically bonds with the bonding agent Restoration interface: The etched porcelain is made reactive by a silane causing it to mechanically and chemically bond to an unfilled resin layer. Then both the tooth and restoration interfaces are linked together by a dual cured hybrid resin luting cement. Depending on the ceramic restoration chosen, the ceramic restoration comes already etched from the lab. Rechecked for the frosty appearance. Clean the restoration of any debris Coat the restoration with a silane coupling agent. Silane makes the etched ceramic reactive to chemically bond to the composite resin to the unfilled resin layer. The coupling agent is volatile and allowed to vaporize leaving reactive silane on the surface. Crispin 1994 A thin layer of unfilled resin or enamel bonding agent is applied is thinned using an air syringe. Avoid pooling that can prevent the restoration from seating. Light cure Once the tooth is prepared and ready for the composite resin luting agent, a thin layer of luting agent is applied to the etched surface of the restoration. The cavity preparation is cleaned using a wet slurry of flour pumice, soft bristle brush, or micro air abrasion. Isolate tooth 37% phosphoric acid is applied to the enamel for 15 seconds and any exposed dentin for 10 seconds. Optional: place matrix band for etching to avoid etching adjacent tooth or beyond margins of prepped tooth. Rinse thoroughly and dry (but not overdried) Resin bonding agent applied, air syringe to a thin layer to avoid pooling. Light cure Apply composite resin luting agent to the preparation (and a thin layer to the restoration, as noted previously) Crispin 1994 Due to thickness and opacity of the onlay/inlay, the composite resin luting agent should be of dual cure capacity. Seat the restoration into the preparation, cement should extrude from the margins. With the assistant stabilizing the restoration, floss and push down again. “Tack” restoration onto the tooth by light curing for about 5-10 seconds. Clean off excess cement and floss (I would recommend your assistant stabilize restoration in place when flossing again). Light cure Occlusally Lateral surfaces Final excess removal Check occlusion and adjust, as needed. Crispin 1994 Occlusal reduction should be uniform and of sufficient thickness for ceramic to provide optimal strength. Thickness of ceramic should be at least 1.5 mm in the central fossa and over nonfunctional cusps. 2.0 mm over functional cusps Cavosurfaces margins should placed to avoid contact with opposing teeth Smoothed and well-defined No beveling on the margins Thin areas of the ceramic are prone to fracture. Onlay/Inlays rely on adhesion of the resin cement to the dentin and enamel for retention. All walls are divergent Prep is nonmechanically retentive Floors and walls should avoid concavities and divots All line angles are rounded Isthmus is at least 2.0 mm to avoid onlay/inlay fracture Sturdevant’s Art and Science of Operative Dentistry, 7th Edition. Contemporary Esthetic Dentistry: Practice Fundamentals. Crispin B., Hewlett E., Jo Y.H., Hobo S., Hornbrook D., Quintenessence Publishing (IL) 1994. Porcelain & Composite Inlays & Onlays: Esthetic Posterior Restorations. Garber D.A., Goldstein R.E. Quintessence Publishing (IL) 1994. Gold #3 MOD onlay https://youtu.be/qITppTM9TIs?si=3TaBbCLISfrl_9o6 Gold #3 MO Inlay https://youtu.be/3MVRX0Fnn-w?si=2FDyYWHtJUsJxt8J Ceramic #3 MOD onlay: https://youtu.be/vbHkHovVp-Y?si=7-2Tc0LMVO6kg6nE Ceramic #3 MOD Onlay Part 2 https://youtu.be/xgGKxviyqIg?si=CuySrpIQOmOM0erT Ceramic #2 MOL Inlay and Dentin Sealing Part 3 https://youtu.be/qe2XPeuNcF8?si=-pRPQt8O1xTPexIh Ceramic Impression and Temporization Part 4 https://youtu.be/uHqzsZeblCk?si=QdpdwgN-XhUx9lry Ceramic Cementation of Inlay and Onlay Part 5 https://youtu.be/gTzbAJaKZBI?si=NCCAXATLPWmXqpOy