Dental Office Visit #1 Preliminary Impressions. Dental Lab Step #1 Pouring Models from Preliminary Impression and Pouring Models

Transcription

1 Dental Office Visit #1 Preliminary Impressions The first procedure is to make preliminary impressions. Preliminary impressions, as related to the Trubyte E.P.F. Technique should be very slightly over-extended to cover the maximum denture bearing area with a minimum amount of displacement of tissue. A preferred material is a quality alginate such as DENTSPLY JeltrateT Impression Material. The Preliminary Mandibular Impression This should clearly show the following anatomical landmarks: The residual ridge, the entire retromolar pad areas, mylohyoid ridges, areas below the lingual margin of the retromolar pads, external oblique ridges, full depth of the anterior lingual crescent areas, and all muscle and frenal attachments of the labial and buccal areas. The Preliminary Maxillary Impression This should clearly show the following anatomical landmarks: The residual ridge, palate, hamular notches, throat form, turberosities, labial and buccal frenum areas, labial and buccal vestibules. Completed alginate preliminary impressions should be poured immediately. Instructions should be given concerning preparation of individual impression trays. This completes phase one in the dental office. Dental Lab Step #1 Pouring Models from Preliminary Impression and Pouring Models Suggested Quality Procedures Recommended Fabrication Steps Quality Standards Quality Failures Pouring Models - Suggested Quality Procedures 1. Read the prescription before beginning all procedures. 2. Box master model impressions (Figures 1a and 1b). Diagnostic casts do not require boxing. Figure 1a Figure 1b 3. Measure dental stone and water according to manufacturer's directions. 4. Add powder to water rather than water to powder. For best results, vacuum mixing is recommended. 5. Do not invert impressions to develop a base until the stone reaches initial set. 6. Use gypsum products according to their intended use, for example Plaster Diagnostic or Study Models Stone Master Casts

2 Mounting Repairs/Matrix Precision Mounting Denture Investment Pouring Models - Recommended Fabrication Steps 1. READ THE PRESCRIPTION 2. Measure powder liquid ratios appropriate to the models to be poured. 3. For alginate impressions rinse the impression and gently vibrate the Labstone into the impression and allow to set. Do not invert the impression, as this will cause the stone to flow away from the impression surface and lose detail. 4. When the Labstone has set, prepare a thick mix of stone to form a base and invert the impression onto the stone patty. Allow to set. 5. Remove the impression tray and alginate and recover the diagnostic cast. Adjust the peripheries of the diagnostic cast using the model trimmer in preparation for the construction of the custom tray. NOTE: Wait least one half hour before removing the cast from the impression. Pouring Models - Quality Standards Master casts 1. Base thickness must be 1/2-inch (13 mm) minimum for strength. This is measured from the deepest part of the palate on the upper (Figure 1c) or the "floor of the mouth" on the lower (Figure 1d). Figure 1c Figure 1d 2. After trimming, the base of the model must be parallel to the residual ridge (figures 1e and 1f). Figure 1e Figure 1f 3. The base must be indexed for mounting and remounting. Two methods are shown here. Other techniques are acceptable as long as the index allows accurate remounting of the model. (Figure 1g).

3 Figure 1g 4. The depth of the buccal sulcus is approximately mm below the land area (Figures 1h and 1i). Figure 1i Figure 1h 5. Positive defects (bubbles), if any, must be in non-vital areas and small enough to be easily removed (1- mm diameter or less as a guide). 6. Negative defects (voids), if any, should be small and in non-critical areas. These should be filled with stone to blend with the surrounding anatomy. 7. The master cast must include all anatomical surfaces in the final impression (Figure 1j). Pouring Models - Quality Failures Figure 1j 1. Inadequate final impression: contact clinician to discuss possible risks of proceeding with the case. (Figure 1k)

4 Figure 1k 2. Model fractures upon removal from impression. 3. Large positive or negative defects, or flaws in critical areas. 4. Poor surface quality of the model due to water/saliva/blood contamination or improper mixing of gypsum, showing a powdery, friable surface. 5. Loss of or damage to critical areas during model trimming (examples: retromolar pad, hamular notch and muscle attachments). Constructing Custom Impression Trays Suggested Quality Procedures Recommended Fabrication Steps Quality Standards Quality Failures Custom Trays - Suggested Quality Procedures 1. Read the prescription before beginning all procedures. 2. Fabricate tray according to clinician's instructions. 3. If no specific instructions are provided, fabricate tray to the following standard: Outline the tray 1-2 mm short of the mucobuccal reflection for both upper and lower models. This will allow room for border moulding material and save time for the clinician. The tray must extend to the depth of the hamular notches on the upper and should cover the retromolar pads on the lower (Figure 2a). The lingual extension on the lower should stop at the mylohyoid line in the posterior and at the junction with the floor of the mouth in the anterior section (Figure 2b). Figure 2a Figure 2b 4. Place relief material such as baseplate wax to the outlined area and cut out three tissue stops. Avoid placing a tissue stop over the incisive papilla. (Figure 2c).

5 Figure 2c 5. Fabricate tray with material of choice to a uniform thickness with a handle in the anterior segment. 6. Remove sharp edges on the processed tray with carbide cutters and polish if necessary. Custom Trays - Recommended Fabrication Steps 1. READ THE PRESCRIPTION 2. Outline for relief wax is usually 2 to 3 mm short of the tray border. Cast undercuts may be blocked out with wax or modeling compound. 3. Warm a single thickness of baseplate wax and adapt to the pencil line as drawn on the cast. 4. Paint areas of the cast to which TRIAD Custom Tray Material will be adapted-as well as the wax reliefwith TRIAD Model Release Agent. Wipe off excess MRA as a thin coating is sufficient. 5. Remove the tray material from the light proof pouch and carefully adapt it to the cast. Excess material may be trimmed with a sharp blade. Do not overthin the material on ridge portion or hammular notch areas of the cast. 6. Attach a handle by moulding excess material into shape and blending edges into the tray material on the cast. (if using original Blue Tray Material, prior to processing, a paper clip or similar wire may be shaped and used to reinforce the handle.) 7. Place the case with the adapted tray in the Triad Curing Unit and process for a maximum of 2 minutes for either Blue Tray Material or TruTray. 8. Remove the cast from the turntable and gently remove the tray from the cast. peel softened wax out of the tray while the wax is still warm. 9. Paint the entire tray with TRIAD Air Barrier Coating, (ABC). Place the tray on the turntable of the Triad unit tissue side up. Process for a minimum of six (6) minutes for Blue Tray Material, and a minimum of two (2) minutes for TruTray. 10. When the cure cycle is completed, remove the tray form the curing unit. remove the water soluble ABC with brush and water. Dentsply Faskut carbide cutters are recommended for adjusting and finishing borders to the desired outlines. Trays may be perforated to aid in retaining impression material. Custom Trays - Quality Standards 1. Unless specified otherwise by the clinician, the wax spacer is 1 mm thick and ends short of the final tray extensions. On the maxilla, wax must not cover the posterior palatal seal area. 2. Tray is well adapted to the model with no voids. 3. Tray must be of uniform thickness. 4. Thickness must be sufficient in strength to prevent distortion or breakage in use. The required thickness will vary with the material used. In general, acrylic resin and similar materials (such as light cure resins) should be approximately 2 mm thick, and 1 mm short of the mucobuccal fold to allow for border moulding. 5. The handle must be placed in the anterior so that it does not interfere with placement of tray or border moulding procedures. The handle may be placed approximately where the wax rim or anterior teeth would be positioned on a baseplate (Figure 2d).

6 Figure 2d 6. Unless specified otherwise by the clinician, the tray borders should be between 1 to 2 mm short of the mucobuccal reflection. Custom Trays - Quality Failures 1. Border extensions significantly longer or shorter than standard. 2. Tray not stable (flexible) due to insufficient thickness. 3. Tray cracked or damaged. 4. Improper handle position (interferes with border moulding or insertion). 5. Sharp and/or rough edges, which may irritate the patient. Dental Office Visit #2 Final Impressions Final upper and lower impressions are made utilizing the custom (individual) impression trays received from the dental laboratory. The impressions may be sent to the dental laboratory with instructions to pour the master casts and to construct stabilized baseplates with wax occlusion rims, completing this phase of the dental office procedures. Impressions are a critical component of successful denture therapy. Here are a few tips that you may find helpful: Before final impressions, make sure the denture(s) is removed and remains out of the mouth for about an hour. You will get a more accurate impression by letting the tissues "rest" for minutes. The best way to do this is to ask the patient to leave the denture out of the mouth overnight and schedule the denture impression first thing in the morning. Some dental professionals feel that it is mandatory to place "pressure release" holes in custom trays, and/or to place a wax spacer for final denture impressions. An abstract on this topic was published recently in the Journal of Dental Research.¹ The authors found that the most important factor related to pressure on the tissue was the viscosity of the impression material, not the presence or absence of holes or "relief" in the impression tray. So place holes and "relief" if you like, but use a light body impression material for the final impression. ¹Masri et al. Journal of Dental Research, Volume 80, Special Issue (AADR Abstracts), January 2001, Abstract #1625 Dental Lab Step #2 Constructing Baseplates and Occlusion Rims Suggested Quality Procedures Recommended Fabrication Steps - read before constructing base Quality Standards Quality Failures Constructing Baseplates - Suggested Quality Procedures (Read recommended fabrications steps)

7 Arch Form 1. To enhance baseplate stability or retention, place/carve the post palatal seal in the model before baseplate fabrication, if possible. The clinical professional should design, prescribe, or place it. See the paragraph on quality standards for guidelines (Figure 3a). Adjust and finish borders to their desired outlines, and then polish as usual. Figure 3a 2. Block out undercut areas with wax, Play-Doug, or DENTSPLY Pumicide but wax is not needed for spacing. Adapt baseplate over the master model so it will fit the mouth comfortably and accurately, but not into undercut areas of the master model (Figure 3b). Figure 3b 3. You may modify baseplates by lining them with an impression material or resilient liner to gain additional accuracy or stability. In this case, some or all of the undercut areas may be used (not blocked out). 4. When the baseplate is separated from the model, remove all remaining wax from both the baseplate and the model. Constructing Baseplates - Recommended Fabrication Steps

8 1. Seal wax boxing rope around the periphery, 1 to 2 mm. below the borders of the impression. The boxing rope is positioned 1-2 mm. below the peripheral roll. The wax is sealed to the impression tray on the reverse surface. 2. Join the wax boxing strip to the boxing rope and seal the waxes with a hot #7 spatula. 3. Mix Labstone Buff, or Castone, in a proportion of 30 cc of water to 100 grams of stone. To pour the impression you will need approximately 45 cc of water and 150 grams of stone. 4. Vibrate mixed dental stone onto all tissue sufaces of the boxed impression in an even flow. So you will not trap air, pour the stone in one corner and allow to flow slowly around the impression to the other corner. 5. Let the dental stone set, remove the boxing wax, and trim the master cast to the proper dimensions as stated at the beginning of this section. 6. For mandibular impressions fold a double thickness of baseplate wax into a triangle form and fold into the lingual area of the impression. Box in the same manner as for the upper impression. 7. Pour the lower impression in the same manner as the upper, taking care not to entrap air in the impression. Rule of Thumb: Make sure to vibrate from one side of the impression to the other so as not to trap air. Constructing Baseplates - Quality Standards 1. Baseplates fit accurately and are stable without rocking, thereby reducing potential for errors in transferring jaw relation records to the articulator. 2. Baseplate material must is not over-thinned on the ridge portion or hamular notch areas of the cast. 3. The position of the posterior border and posterior palatal seal corresponds to the arch form class shown in Figure 3b. A good rule to follow is to position the posterior border 2-mm posterior to the foveae palatinae. The preferred method for establishing the post dam is for the clinician to prescribe the location and design. 4. The post dam most commonly used is butterfly shaped (Figure 3e) to follow the contour of the palate. As a guideline, the posterior seal depth will be 1/2- to 1-mm deep in the hamular notch area increasing to 1 1/2- to 2-mm deep in the area between the notch and the fovea, then blending to 1/2- to 1-mm deep in the foveae area (Figure 3c). Figure 3c

9 5. As an alternative, the post dam may be a simple bead design. The bead will be 1- to 1 1/2-mm deep, 1 1/2-mm wide at its base, and sharp at its apex (Figure 3d). Figure 3d 6. Borders are properly trimmed and polished. Constructing Baseplates - Quality Failures 1. Baseplate cannot be removed without damaging the model if it is adapted into undercut areas. 2. Baseplate cracks during processing or finishing. 3. Baseplate is unstable, distorted and/or rocks on the model. Occlusion Rims Suggested Quality Procedures Recommended Fabrication Steps - read before constructing base Quality Standards Quality Failures Occlusion Rims - Suggested Quality Procedures 1. Use a controlled temperature water bath heated to 120 F (49 C). Immerse the bite rim stick in the water for 3 minutes or until soft enough to manipulate it to the desired shape. 2. A bead of sticky wax placed onto the baseplate ridge crest will help secure the bite rim into position. 3. After placing the rim into position, smooth the labial and lingual areas of the wax to the appropriate contour and trim anterior areas to a thickness of 3- to 4-mm. The width at the first molar region should be between 8- to 10-mm. 4. In the anterior, use a millimeter ruler to measure the distance from the mucobuccal fold: 22-mm on the upper and 18-mm on the lower. Mark the area and smooth the wax to these dimensions (Figure 4a). The posterior plane of occlusion should not exceed 2/3 of the retromolar pad height. Figure 4a 5. Smooth the wax rims with wet cotton rolls.

10 6. Use an Trubyte Alma Gauge to record the wax rim dimensions based on the location of the papilla. The incisal edge of the upper central anteriors (X dimension) is x-mm below the papilla and y-mm in front of the papilla (Y dimension). This dimension may be altered later by the clinical professional (Figure 4b). Figure 4b Occlusion Rims - Recommended Fabrication Steps 1. Follow quality procedures listed above. Occlusion Rims - Quality Standards 1. Wax rims are smooth and have a flat occlusal surface. They are about as wide buccolingually as denture teeth wider in the posterior, narrower in the anterior (Figure 4c) Figure 4c 2. The occlusal rim must be centered buccallingually over and parallel to the residual ridge crest. 3. The anterior portion of the maxillary occlusal rim is labially oriented (Figure 4d). Figure 4d 4. The anterior wax rim height is 22-mm on the maxillary and 18-mm on the mandibular arch. 5. The width of the anterior rim is approximately 3- to 4-mm thick. 6. The width of the occlusal rim in the posterior region is approximately 8- to 10-mm thick. 7. The occlusal rim is properly sealed to the baseplate without any voids. 8. The posteriors of the occlusion rims are cut at a 30º angle to the occlusal plane to eliminate potential interference during bite registration (Figure 4e).

11 Figure 4e 9. The baseplate border length and thickness (approximately 2-mm) is approximately the same as the final denture base. Occlusion Rims - Quality Failures 1. Voids or other defects are present. 2. Height, length, width, and thickness of wax rim are incorrect. 3. The wax contains dirt, debris or foreign material. Dental Office Visit #3 Occlusal Registration Contour the maxillary occlusion rim and mark the patient's midline The maxillary occlusion rim should support the upper lip and the facial-incisal edge of the contoured occlusion rim should contact the vermillion border of the lower lip when the patient repeats fricative ("f") sounds. Define occlusal plane using the mxillary occlusion rim. The patient's vertical dimension and occlusal plane is established during these procedures. The Trubyte (Fox) Occlusal Plane Plate is an excellent aid in determining the most desirable occlusal plane for the patient. The relationship of the Trubyte (Fox) Occlusal Plane Plate should be used to confirm that the maxillary occlusal plane when viewed from the anterior parallels the plane which passes through the center of the patients pupils when the patient is standing or sitting erect. W hen viewed sagitally, the maxillary occlusal plane should parallel the plane which contains the patient's Ala-Tragus line when the patient is standing or sitting erect. Establish preliminary centric relation The preliminary centric relation registration should be as accurate as possible. The occlusion rims should index accurately to be secured together. Determine closest speaking space and recording preliminary centic relation Prior to recording the preliminary centric relation, contour the mandibular wax occlusion rim such that it is parallel to the maxillary occlusion rim when the patient speaks sibiliant ("s") sounds. The occlusion rims should closely approximate each other but should not contact even when the patient counts quickly from sixty to seventy. The contour of the mandibular occlusion rim should be such that it does not interfere with lip and cheek position during speaking or swallowing and does not interfere with the tongue during speaking. Record the maxillo-mandibular relationship at the occlusal vertical dimension. Index the posterior aspects of each wax occlusion rim and encourage the patient to close until the rims contact with their mandible retruded as far as possible. Record this closed position using wax or a polyvinyl siloxane registration material such as "Regisil. Select Trubyte Teeth A preliminary centric relation registration, along with complete information regarding moulds, color, and type of teeth, as well as a desired tooth arrangement is then transferred to the dental laboratory.

12 Dental Lab Step #3 Model Orientation and, Tooth Set Up and Articulation, and Wax Conditioning Model Orientation Suggested Quality Procedures Quality Standards Quality Failures Model Orientation - Suggested Quality Procedures: 1. Determine and mark the central bearing point of the maxillary (upper) model by locating the median suture line and bisecting it (halfway between the extent of the labrial flange - adjacent to the frenum and the posterior border position) (Figure 5a). Figure 5a 2. Find the ideal mounting point on the upper arm of your articulator by: 1. Determining the inter-condylar distance on the articulator hinge (Figure 5b), line "A" on Figure 5c. Figure 5b Figure 5c 2. Use Figure 5c to determine proper distance from the articulator hinge for the central bearing point "B" on the model for your articulator. 3. When mounting the upper model to the articulator, be sure to place index marks in the model sufficient to ensure accurate re-mounting of the case after processing. 4. An intra-oral tracing (gothic arch tracing) is highly recommended for predictable results and to decrease clinical occlusion problems. If the clinical professional does not provide a gothic arch tracing, clinical use of an intra-oral balancer (such as the Coble 1 Balancer) can help minimize occlusal adjustment time and lead to greater success and patient satisfaction.

13 5. Casts must be centered in the articulator for best results if a face bow is not used. 1 Coble is not a trademark of Dentsply. Model Orientation - Quality Standards: 1. The mounting is clean and free of plaster debris. 2. If a semi-adjustable articulator is used, the horizontal condylar angle, Bennett angle, and incisal angle should be set according to the clinician's instructions. It is best to use a protrusive bite registration to determine the correct condylar angle. If not provided, defer to average values (30º condylar, 15º Bennett, and for incisal guidance settings, refer to the suggested "Procedures for the Arrangement and Articulation of Trubyte Anterior and Posterior Teeth", item #4087-A). 3. Use mounting stone for maximum accuracy. Model Orientation - Quality Failures 1. The upper and lower ridges are significantly divergent from a parallel relationship. Note: This can occur with unusual bone resorption patterns. 2. Inter-arch distance is insufficient to set denture teeth. 3. Centric relation record: Upper and lower baseplates contact each other (interfering with proper centric relation) in the retro-molar/ tuberosity areas. 4. The upper and lower models contact each other and interfere with mounting procedures. Model Orientation Suggested Quality Procedures Quality Standards Quality Failures Tooth Set Up - Suggested Quality Procedures: 1. Read the prescription before starting procedure. 2. If the clinical professional does not choose a tooth mould, select teeth of appropriate size and contour based on the patient s anatomical measurements, face form, gender, and age, if available. A "high smile line" marked on the maxillary wax rim will greatly improve the reliability of the estimate. Base the posterior teeth mould size on the remaining ridge length and anterior mould selection. 3. Make sure the trial base plate is well adapted to the master model (Figure 6a). Figure 6a 4. Set teeth according to tooth manufacturer's directions for use or clinical professional's instructions. 5. Use minimal set-up wax to secure the teeth in position. 6. Use baseplate wax for contouring the wax denture following natural gingival contours or according to clinical professional's instruction. Tooth Set Up - Quality Standards:

14 1. The wax is anatomically contoured (Figure 6b). Figure 6b 2. The anterior tooth position matches the position and incisal length prescribed by the clinical professional or as represented in the wax occlusion rim. Use a Trubyte Alma Gauge to verify (or modify) correct anterior tooth position. 3. The posterior occlusion is in correct contact in centric, working, and balancing relationships according to the tooth manufacturer s directions for use or according to the clinical professional s instructions (Figures below). centric buccal centric lingual working buccal working lingual balancing buccal balancing lingual 4. Exposed surfaces of the denture teeth must be free of wax. 5. The entire set up including the mounting and the articulator must be clean and free of extraneous wax to enhance presentation in the dental office. Tooth Set Up - Quality Failures

15 1. Teeth move during wax contouring. 2. The wax-up does not follow natural gingival contours. Note the contrasting natural gingival countour (Figure 6c) with non-anatomical features such as the concave papilla and knife-edge margins (Figure6d). Figure 6c Figure 6d 3. Debris from waxing units or other foreign material is present in the wax-up 4. Thickness of wax is not to clinical professional's specifications. Dental Office Visit #4 Try-In Try-In for anterior esthetic evaluation and modification When a desirable vertical relationship has been determined with the try-in tooth arrangement, the tracer assembly is opened (or closed) to that same dimension and then employed to record the patient's Gothic Arch Tracing. An adhesive disc is positioned on the tracing and the top covering is removed to show the tracing. The clear plastic centric lock disc is positioned with the hole over the apex of the tracing using the positioned needle or by "eye-balling" the hole over the apex. Quick setting stone or plaster is placed on the buccal sides of the upper and lower assembly, engaging the notches in the wax and entering the open space between the upper and lower assembly. When the material forming the centric locks has set, the tracing assembly may be removed from the mouth. The materials to be returned to the dental laboratory after these procedures are completed are: the tooth arrangement with any modifications which may have been necessary (tooth positions, vertical dimension opened or closed, etc.), the Gothic Arch tracer assembly with centric locks (the tracing should be made at the same vertical dimension as determined by the try-in tooth arrangement), along with additional specific instructions concerning the tooth arrangement, processing, finishing or another try-in if necessary. OR... Try-in for completed tooth arrangement, proper posterior occlusion, and wax contouring detail. Esthetic considerations at Try-in time: 1. Midline harmony with facial features 2. Relation of anterior teeth to the lips 3. Prominence of canines 4. Antero-posterior of anterior teeth 5. The occlusal plane (check with Trubyte (Fox) Occlusal Plane Plate) 6. Consideration of overall esthetic and phonetic factors 7. Vertical dimension 8. Centric relation 9. Overall patient comfort and acceptance.

16 Dental Lab Step #4 Denture Processing and Denture Finishing Suggested Quality Procedures Quality Standards Quality Failures Denture Processing - Suggested Quality Procedures 1. Read and understand the prescription before starting procedure. 2. Make sure the denture wax-up accurately represents the proper gingival and arch form, following guidelines for accepted oral anatomy (Figure 7a). Wax the denture to the full contour and properly seal it to the master model. Figure 7a 3. Lubricate the models properly with petrolatum or separating agent to assist in cleaner, easier devestment and less finishing labor.. 4. Vacuum mix investment stone for best results or mix hydrocolloid to manufacturer s recommendations. 5. Pour investment properly to minimize bubbles by filling the flask from one side to the other allowing air to escape. This is the same technique as pouring an impression. 6. Thoroughly boil-out and flush wax residue from invested case with clean boiling water. This prevents contamination of the processed denture base resin (Figure 7b). Figure 7b 7. If mechanical retention is desired to secure teeth, prepare the teeth after removing wax and cleaning the denture mould. Use minimal drilling and grinding to minimize weakening of teeth. A chemical bonding agent may be used on plastic teeth if desired. 8. Whether packing, pouring, injecting, or microwaving, prepare and process the acrylic resin exactly to the manufacturer's directions for use. Thorough cleanliness is essential during the mixing and packing of the acrylic resin. 9. When injecting acrylic, position sprue according to the manufacturer s technique (Figure 7c and 7d).

17 Figure 7c Denture Processing - Quality Standards Figure 7d 1. Processed denture base is free of porosity and contaminants such as investment debris (Figure 7e). Figure 7e 2. Processed dentures do not have excessive increase in vertical dimension as confirmed when remounted on the articulator. 3. Processed dentures are free of visible flaws or defects. Denture Processing - Quality Failures 1. Processed denture has internal porosity and/or large voids (Figure 7f). porosity Figure 7f large void 2. Processed denture has excessive increase in vertical dimension (more than1.5-mm). 3. Tooth movement causes improper articulation. 4. Excess melting of wax during boil-out penetrates investment making devesting difficult or discoloring acrylic. 5. Note: There are no ways to check for disasters during pack, pour, or injection procedures. Following the directions for use is the best way to avoid remakes. Denture Finishing Suggested Quality Procedures Quality Standards

18 Quality Failures Denture Finishing - Suggested Quality Procedures 1. Use care when removing investment from the restoration, especially when using power devices (Figure 8a). Remove investment starting at the posterior section and moving toward the anterior section. Avoid using force. Figure 8a 2. If available, use walnut shell abrasive to remove gross investment. If not, use ultrasonic stone and plaster remover in an ultrasonic unit for thirty (30) minutes. 3. Use light pressure on the restoration when using a lathe or handpiece. 4. Use coarse abrasives and burs first, if needed for gross reduction. Use finer abrasives to finish. 5. Check for flash on the teeth, but do not over-polish acrylic denture teeth. Denture Finishing - Quality Standards ACRYLIC APPEARANCE 1. Denture base is clean without traces of investment or polishing media present on denture base surface. 2. Contours mimic nature and follow the desired criteria of the restoring clinical professional and patient. 3. All edges are rounded and smooth, but not over-polished. 4. Stippling and festooning, if desired, is subtle and follows accepted criteria for appearance and contour (Figure 8b). Figure 8b 5. Tissue bearing surface of denture base must be free of sharp edges and positive or negative defects (bubbles and voids). OCCLUSION / TEETH 1. There should be minimal pin opening on the articulator when the restorations are remounted. 2. The appliance should have even contact on all occlusal surfaces. 3. Premature tooth contacts are removed carefully with selected grinding procedures; using care to maintain an aesthetic tooth appearance. 4. Labial, buccal and lingual surfaces of denture teeth should not require polishing. Denture Finishing - Quality Failures

19 1. Denture breaks when investment is removed. 2. An over-polished tooth surface shows loss of labial, buccal and lingual anatomy. 3. Tissue surface of denture wax inadvertently polished, creating loss of retention and fit. 4. The denture base is burned or discolored from heavy pressure or extended polishing with a lathe and/or handpiece. (Figure 8c) Dental Office Visit #5 Deliver Final Dentures Figure 8c At this appointment, consider the following key elements of denture insertion: 1. Evaluate fit and stability 2. Evaluate esthetics 3. Phonetic evaluation 4. Occlusion relationship The pleasing final result... the procedural recommendations of the Trubyte Esthetic, Phonetic, Functional Complete Denture Technique can consistently provide patients with prosthetic restorations that look and function in such complete harmony with their appearance and personality that they are virtually indistinguishable from healthy natural teeth... As always, that is a tribute to the successful collaboration between the dentist and the dental technician. Patient Communication As a reminder, communicate issue with the patient such as ridge resorption, and limited life of a denture. Inform patients about a website dedicated to patient denture issues: Print denture care instructions for your patients.