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Complete Dentures The Wax Try-In.

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Presentation on theme: "Complete Dentures The Wax Try-In."— Presentation transcript:

1 Complete Dentures The Wax Try-In

2 Introduction Goals: Evaluate and finalize the anterior esthetics.
Verify the vertical dimension. the occlusion. Following this lecture, the student should be able to evaluate and finalize the anterior esthetics, verify the vertical dimension, and evaluate and finalize the occlusion based on sound prosthodontic principles

3 The student/practitioner should:
Complete the wax-up/set-up. Evaluate all aspects of the set-up. Obtain patient approval. Prior to this appointment, the student should have completed the wax-up/set-up. During this appointment, they will evaluate all aspects of the set-up and make modifications as necessary, then obtain patient acceptance of the anterior esthetic arrangement of teeth. Obviously, they should appear knowledgeable and comfortable in performing the procedure.

4 Armamentarium Mounted Casts/Wax Dentures. Dental floss. Fox plane.
Denture Adhesive. Hand Mirror. Cup of water. Mold Chart. Denture tooth shade guide. Denture base shade guide. The student should bring to the clinic or obtain from the side lab or the dispensing area all the instruments and materials necessary to reset the teeth during a wax try-in appointment. It is always better to be over-prepared than to be under-prepared for any eventuality and thereby avoid any possible delay in treatment.

5 Armamentarium Tongue blade. Baseplate Wax. Flexible Ruler.
Waxing Instruments. Bunsen burner. Alcohol torch. Indelible transfer stick. Red-handled knife and a sharp blade. Green handled knife.

6 Prior to this appointment, the wax dentures are completed
Prior to this appointment, the wax dentures are completed. All teeth are set properly and the wax-ups are festooned properly. Zero-degree, monoplane occlusions must have perfectly flat occlusal planes on both maxillary and mandibular dentures. It is important that all the teeth be set and the wax properly contoured for the wax try-in appointment, because the shape of the denture base area as related to the teeth will have a considerable bearing on the aesthetic properties of the denture. The patient will be signing a statement in the record that they approve of the anterior aesthetics, but the student dentist must be able to evaluate the denture wax up for the vertical dimension of occlusion, phonetics, paralellism of the occlusal plane to anatomic landmarks, and prematurities in the occlusion. If this is not done at this appointment, the patient should be reappointed for another evaluation of these areas of responsibility.

7 Flat planes should exist from the mid-buccal of the canines to the mesio-buccal of the first molars and from the mesio-buccal of the first molars to disto-buccal of the second molar on a plane turned approximately 20o toward the palate from the first plane so that the buccal surfaces of all molars are in a straight line. This rule applies to both anatomical teeth and zero-degree teeth. If the buccal surfaces of the bicuspid teeth do not fall on the line from the mid-buccal of the canine to the mesiobuccal of the maxillary first molar, the denture will have a characteristic Cheshire cat look, or toothy smile. The patient may return with complaints that their friends thought that dentures were unesthetic and want them remade, even though they signed that they liked the look of the dentures initially.

8 Mandibular posterior teeth must be set so that they are over the crest of the ridge, with zero-degree teeth set so that the central fossas lie directly over the crest and anatomic teeth set so that their buccal cusps are over this line. With severely resorbed ridges, lines are drawn from both sides of the retromolar pad and intersect at the canine. The teeth would be set so they fall between these two lines. With severely resorbed ridges, the crest of the ridge is almost impossible to determine and is broader based, therefore there’s more flexibility in setting the posterior teeth. To determine the more ideal position for setting the posterior teeth, lines are drawn from both sides of the retromolar pad and intersect anteriorly at the point of the cusp for the mandibular canine. This is not done with well-developed ridges, however.

9 The mandibular anterior teeth should not be placed further forward than a line drawn perpendicular to the occlusal plane from the middle of the labial vestibule. To do so would place the mandibular anterior teeth ahead of the axis of rotation and contribute to instability of the mandibular denture. The anterior teeth should not be placed further forward than a line drawn perpendicular to the occlusal plane from the middle of the labial vestibule.

10 The buccal surfaces of the maxillary posterior teeth must not be placed any more buccally than a line perpendicular to the occlusal plane drawn from the depth of the buccal vestibule. If ideal positioning of the mandibular posterior teeth dictates that maxillary posterior teeth must be set more buccal than this rule allows, the maxillary teeth must be set in crossbite. The buccal surfaces of the maxillary posterior teeth must not be placed any more buccally than a line perpendicular to the occlusal plane drawn from the depth of the buccal vestibule. If ideal positioning of the mandibular posterior teeth dictates that maxillary posterior teeth must be set more buccal than this rule allows, the maxillary teeth must be set in crossbite.

11 Denture teeth should not be set on maxillary tuberosities.
Zero-degree teeth set in a monoplane occlusal scheme is desired for all crossbite situations in the pre-doctoral clinic. Denture teeth should not be set on maxillary tuberosities. Denture teeth should not be set on the retromolar pad as this would create forces that would dislodge the denture anteriorly. In the pre-doctoral clinic, students will set zero-degree teeth set in a monoplane occlusal scheme for all crossbite situations, because of the difficulty of establishing a balanced occlusion in all the eccentric movements of crossbite patients. Cusped teeth are designed to be set in a certain way and they will not line up properly when set in crossbite. Denture teeth should not be set on maxillary tuberosities or on the retromolar pad as well, as this would create forces that would dislodge the denture as the forces generated in the back of the mouth are very strong and will press the denture down this incline and move it forward.

12 While nobody is perfectly bilaterally symmetrical, it is commonly accepted that the closer someone is to being that way the more aesthetically pleasing they are in their appearance. This ruler is a valuable tool in providing a simple means to enable the technician to design dentures that are very close to being bilaterally symmetrical. This has broader implications than aesthetics. It is much easier to establish bilateral balance in all excursive movements in a set of complete dentures that are bilaterally symmetrical in their tooth arrangement than it is in a set that is not symmetrical. Sadly, it is impossible establish this harmony in many patients, and this is where the zero-degree, monoplane setup is very useful. A TrubyteR Millimeter Rule will aid in enhancing the curvature of the arch and impart a more balanced look to a denture.

13 Things to Check Fit and Extension of Denture Bases.
Labial Flange thicknesses in Frenum Areas. Posterior Palatal Seal Area. Posterior Tooth Positions: 1. Relation of Plane to Retromolar Pad. 2. Relation of plane to Ala-Tragus Line. 3. Tongue Space. 4. Ridge Relationship. One of the most common areas of the lower denture that is overextended is the labial flange. This is checked with the denture out of the mouth and the lower lip is pulled up and out to reveal the areas of attachment of the muscles. This depth can be measured using a periodontal probe and then these measurements are transferred to the flange. The flange is then reduced to this height and the denture is inserted in the mouth. When the lip is pulled up and out, the denture is observed to see if it is displaced. Another area commonly over-contoured is the lingual flange in the area of the lingual frenum. The patient is advised to raise their tongue and touch the roof of the posterior palate. Again this height can be measured with a periodontal probe and this measurement is transferred to the denture. The denture is then reduced in this area, replaced in the mouth, and observed to see if it is displaced when the tongue is raised. Since the posterior palatal seal area is arbitrarily placed, it will generally require some adjustments and is tapered on the polished side so that the tongue will pass over it unimpeded.

14 Things to Check VDO & VDR Centric relation (CR) Protrusive
Esthetics and phonetics Posterior palatal seal Physiologic rest position Phonetics and esthetics Ability to swallow Compare to old denture. One of the main things we have to consider when we look at old dentures for comparison to our own measurements is that the old dentures may never have really been the proper vertical dimension or that the vertical dimension has changed over the years of wear. They have to be a consideration because the patient has adapted to the old denture and will need to readapt to new dentures. The patient must be made aware of this factor and be willing to devote the time and effort it takes to adjust to the new dentures.

15 Things to Check Positions of Anterior Teeth 1. Lip Support 2. Length
3. Relation to upper lip 4. Interpupillary line 5. Midline 6. Phonetic exercise: “F” sounds (length of max. anteriors). Wax-up. 1. Lip support. 2. External form. To make it a distinct ‘F’ sound, patients must be able to place the wet/dry line of their lower lip against the incisal edge of the maxillary incisors. Also, if the maxillary incisors are inclined toward the palate there will not be proper support rendered by the teeth to the upper lip. This is sometimes seen when the technician attempts to minimize the horizontal overlap of a skeletal class II patient. When this is done, the patient will often complain that the labial flange of the maxillary denture is too long or too thick.

16 Things to Check Vertical Dimension of Face.
1. Phonetic exercise: “S” sounds 2. Palatal contour 3. Swallowing Esthetics 1. Picket fence or chicklets appearance 2. Too much or too little of teeth show. 3. Color (Shade) 4. Size (mold, length & width) 5. Too much base material is visible. If a denture increases the patient’s vertical dimension of occlusion, it will be difficult for the patient to swallow. The posterior teeth may also click together when the patient talks. If the vertical dimension is decreased, the patient may drool at the corners of the mouth, and ‘S’ and ‘X’ sounds may sound like a ‘th’ sound. Every effort must be made to provide the patient with a set of dentures that provide a natural appearance. For this treason, it is a good idea to look at pre-extraction casts and photographs. Ask the patient if they want their teeth to be overlapped or twisted, or if diastemas in the natural teeth are to be duplicated in the dentures. Such changes can be provided as long as the rule of bilateral balance in the occlusion is not violated. The size, shape and color of the teeth must be accepted by the patient prior to processing the dentures, and they must sign a statement in the record indicating their approval.

17 Things to Check Positions of.Posterior Teeth
1. Is the occlusal plane parallel with ala-tragus line? 2. Does the occlusal plane allow the patient to move in protrusive relation w/o the maxillary posterior teeth contacting the heels of the mandibular denture? 3. Are posterior teeth set in an end to end relationship in occlusion? 4. Do premature occlusal contacts exist? The patient must be able to occlude their teeth properly in eccentric movements. Parallelism of the occlusal plane with the ala-tragus line is of secondary importance. It is easier to set the posterior teeth if they are positioned so that the plane of occlusion divides the interarch distance by ½. The patient’s ability to move their jaw in lateral and protrusive movements must be unobstructed within a normal range of motion. This requires that the plane of occlusion must intersect the posterior rise of the mandible at a point at least 2/3 of the way up the retromolar pad. Any amount less than this will restrict the patient’s ability to move in a normal range of motion as the most distal maxillary tooth will contact the heel of the lower denture. Also, teeth that contact in an end to end relationship tend to cause the patient to bite their cheek or lips, because they do not position the lips or cheek away from the point of contact when the patient chews.

18 Things to Check Patient Instructions.
1. Dentures fit better than baseplates because the undercuts are blocked out. 2. The color of the denture base is selected to match the natural color of the patient’s gums. 3. There are only a few tooth shades available for denture teeth. One thing that must be assumed when dealing with a complete denture patient is that they very likely have little knowledge about dentures. They may have been misinformed about the limitations of dentures, or otherwise have some unreal expectations. Regardless of how many years a patient has been wearing dentures, they will still need to be provided with instructions, both orally and in writing. If they don’t accept your instructions or otherwise claim to know more than you do about dentures, you may want to consider not treating them.

19 Esthetic Set-Up Factors: Tooth Alignment Golden Mean Anatomic Contours
We have already discussed how tooth arrangement affects the perception of aesthetics. The Golden Mean (no relation to yours truly) was established when it was noticed that the inter-relationship between the width of the anterior teeth has considerable effect on aesthetics. Also, the shape of the teeth are related to the shape of the face for striking a balance between the individual teeth and a patients facial features for improved aesthetics. It was found that the maxillary anterior teeth are more aesthetic when viewed from the facial at the central incisor region if each tooth differs in the width of tooth visible from its more anterior neighbor by a ratio of 1 to This proportion is commonly known a the Golden Proportion or Golden Mean.

20 Tooth Alignment Midline is centered with the patient’s face.
This is a computer-generated picture and is not a picture of an actual patient. Two of the most important evaluations you will need to make are that the midline of the dentures line up with the middle of the patient’s face and that the anterior occlusal plane lies parallel to their interpupillary line. A patient will notice these two things in a mirror and their friends may comment on them to the patient. Midline is centered with the patient’s face. Occlusal plane is parallel with the eyes.

21 Smile Line Should follow the contour of the lower lip.
Two things that patients and their friends will also notice are related to how attractive their smile appears. The curvature of the anterior teeth should match the curvature of the lower lip and the patient should not show any denture base above the coronal portion of the teeth. Varies with each patient.

22 Esthetics CSS Smile Line Relaxed Positive Negative
Closest speaking space (CSS) is used for the final test to determine if the vertical dimension is correct. Different amounts of teeth are visible when the patient speaks than when they smile. Use “s” sounds Count from 60-70 The main thing that you do not want to happen is to cause the patient to show too much gum when they smile. To avoid this, the high lip line is marked on the wax rim and the mold of teeth to be set is selected accordingly. This is one of the steps that is closely checked during the wax try-in appointment. When the patient signs the record indicating their acceptance of the anterior aesthetics of the teeth this is one area that they will be looking at, therefore, it is important that all of the posterior teeth are set and a proper festooning is completed prior to this appointment.

23 Plane of Occlusion Anterior-Posterior Horizontal Orientation.
Parallel With Patient’s Eyes Anteriorly. The plane of occlusion is adjusted so that it is parallel to the ala-tragus line anteriorly and posteriorly, and parallel with the inter-pupillary line. The most important aspects of this plane are that it lies parallel to the inter-pupillary line and is located at the proper vertical dimension for esthetics and phonetics (Normally 1-2 mm below the resting lip). This is the component of the occlusal plane that everyone sees. Other people seldom notice the occlusal plane in the posterior area.

24 This is a computer-generated picture and is not a picture of an actual patient.
It is important to remember that anatomical landmarks such as the nose are guides to the placement and size of teeth, not ironclad rules. A patient could have a rhinoplasty (nose job) done and the size and shape of the nose may not represent a relationship to the size and shape of the teeth. The arch form is more of an indicator as to where the teeth should be set and even then, the width of the patient’s natural teeth may have been compromised by overlapping or have diastemas and the arch form will not indicate the size or shape of the teeth. For this reason, I always select the size and shape of the teeth without the patient being present, and get their approval at the wax try-in appointment. In many people, the width of the six anterior teeth and the width of the nose are approximately the same.

25 Length of Maxillary Centrals
Should lie just above the resting lip. Should contact the wet-dry line during speech (F,V sounds). An often overlooked factor at the insertion appointment is that the labial flange of the lower denture is overextended. If this is the case, the lower lip will not be able to touch the incisal edges of the maxillary anterior teeth without raising the lower denture. This is probably the most often overlooked aspect of complete dentures during the insertion phase. If this deficiency is not corrected prior to the clinical remount, the remount will be incorrect and any occlusal adjustment made during the remount will likewise be inaccurate. The patient will usually not complain if the flange is slightly overextended at the insertion appointment, but at the 24 hour check there will usually be a visible ulcer in this area and the patient will complain that it is too long. This results because as the denture rises and settles during normal function, the denture pinches the tissue.

26 Fricative sounds: Patients should be able to make clear “f” and “v” sounds when the incisal edges of the maxillary central incisors contact the lower lip. “F” and “V” sounds The sounds made when the patient’s lower lip touches the maxillary incisors are the “f” and “v” sounds. A good way to assess this is to have the patient count from fifty to sixty and watch carefully as the patient says “fifty-five”. If the “v” sound doesn’t come out clearly (usually sounds like a “b” sound), then the lower lip is not touching the teeth correctly and a change must be made to correct this deficiency during the anterior wax try-in appointment.

27 Maxillary anteriors are in harmony with lower lip.
If the maxillary anterior teeth are set in a position that is too low, the patient will struggle to position the lip correctly, but it will contact the teeth prematurely. This will create a “f” sound instead of a “v” sound when the patient says “fifty-five” and it will sound like “fifty-fife” and the “f” sounds will be somewhat “airy” as the air is forced unnaturally over the teeth. The patient will also generally spew saliva when speaking if the maxillary anterior teeth are too long. Maxillary anteriors are over-long and collide with the lower lip.

28 Sibilant Sounds During the production of the Sibilants (“s” or “z”) sounds: a) The anterior and posterior teeth should not collide (no clicking). There should be no hissing or air loss (not sound like “th”). The closest speaking space should be 1.5 to 3 mm at the second molar region. The patient will move the jaw 2-3 mm forward during speaking. If the vertical dimension of occlusion is increased, the teeth will contact prematurely and give a clicking sound. Instruct the patient to count from sixty to seventy to assess the vertical dimension, and carefully listen to observe the sounds that are made when the patient says ”sixty-six”. The sound may come out a clicking sound (sixty-six) if the increase is slight, sixty-six if the VDO is more open, or a “th” sound (sickthy-sikth) if the vertical dimension is decreased and the tongue is placed between the teeth to fill the gap.

29 The plane of occlusion of a complete denture with the second molar left off to match the mandibular posterior teeth where there was insufficient room to set the mandibular molar without setting it on the rise to the mandible. Sometimes a tooth must be left out to accommodate the patient’s anatomical configuration or to allow the patient to move the lower jaw into eccentric positions. This can be due to a steep rise of the ramus or a severe class II skeletal relationship. The posterior teeth should not be set on the slope of the ramus nor should the maxillary molar contact the lower denture base when the patient moves into protrusive or lateral positions. Either a molar or a premolar may be left out of the set-up, depending on the size of the area necessary to allow adequate movement.

30 Verify Centric Relation
Insert dentures and hold lower in position with your index fingers. Retrude the mandible and close into centric relation. Observe any shift in the upper denture. Look for even contact of the posterior teeth bilaterally. It is difficult to fully evaluate the occlusion during the wax try-in phase. Be aware that each phase of complete denture construction is only as accurate as the steps completed prior to that particular phase allow it to be. A baseplate is not as accurate as a denture base. Teeth set in wax will shift in the patient’s mouth. Baseplates will allow movement so that the teeth appear to be in ideal contact, even though they are not. Such minor discrepancies must be resolved during the clinical remount. Note the separation of the posterior teeth in CR. This patient’s centric relation is incorrect.

31 Note the separation of the posterior teeth in protrusive in this patient. This situation would not work because denture would impact constantly on the anterior ridge, creating instability, and greatly increasing the rate of resorption. The diastemas between the teeth are permitted at the patient’s request or with their approval. It is important to note that if the anterior denture teeth contact prematurely, the lack of contact in the posterior teeth will cause the lower denture to tip forword until the posterior teeth actually come in contact. This creates a phenomenon called the combination syndrome or Kelly syndrome. This out of balance relationship will create undue pressure on the maxillary anterior ridge and increase the rate of bone resorption. This condition is particularly common in patients with a class II musculoskeletal relationship and occurs when the posterior teeth wear down more rapidly than the anterior teeth because of the more frequent contacting of those teeth during the mastication process. This is the main reason why porcelain anterior teeth are not used with plastic posterior teeth. Such a condition will need to be corrected prior to the relining of the dentures or the instability that exists will not be corrected by the relining procedure.

32 Verify Centric Relation
Soften a stick of compound over a Bunsen burner. Place the compound onto the occlusal surfaces of the mandibular posterior teeth. Temper the compound in a water bath set at the proper temperature (110o) and smooth it with your wet gloved finger. (140o if green stick compound is used.) Obviously, anytime that we’re working with the base plate it is not going to be as accurate as a processed denture base. Often, however, there will be an obvious discrepancy in occlusion of the wax dentures intraorally. This is an easy way to determine the correct centric relation. In this illustration, red stick compound is used for the purpose of the bite registration. The green stick compound we normally use when border molding would be very suitable for this purpose as it is very accurate and stable, however, in the complete denture clinic “Take One “ bite registration material will normally be used. In some cases, the teeth can be left as they are and the indexing material placed between them. Often, if the vertical dimension will not support this alteration, the mandibular posterior teeth will need to be removed. The patient is then gently guided into occlusion and the registration material is allowed to harden before removal from the mouth. Immediately after removal, a quick check is done to determine if the heels of the lower denture are contacting the denture base of the upper denture.

33 Make a centric relation record
Recline the chair back, this will help retrude the mandible. Stabilize mandibular base with your index fingers on the buccal flange and the thumbs under the mandible (bimanual technique). Rehearse closing with the patient. Have patient gently close into the compound just short of tooth contact. When you do this bite registration, you must ensure that the patient is giving you a true centric relation. Class II patients tend to be more difficult than others to achieve an accurate record because they traditionally tend to posture forward of this position. The true centric relation record must be obtained to mount the cast correctly on the articulator, because although the patient may not normally bite down in centric relation, he will most certainly go to that position on the rotating side of his condyle during lateral movements. The entire process of making a bite registration must be explained to the patient and a few dry runs completed in order to get a good bite registration. Once this is done, the cast and the lower denture can be remounted on the articulator and the teeth adjusted to fit this new position. It is very helpful if this repositioning of the teeth is done while the patient is still seated in the dental chair.

34 Place the new record onto the master casts on the articulator.
Remove and trim the record so that only the indentations from the cusp tips are present. Place the new record onto the master casts on the articulator. Make sure the articulator condyles are locked in centric position. Close the articulator. If the maxillary teeth contact the indentations exactly as they did in the mouth, you have proven that your original centric record was correct. It is vital to the accuracy of the bite registration that the teeth must seat fully into this index. In order that this can visually assured, any excess material is removed from the index, leaving only the cusp tips in the record. This will allow enough visual access so that the teeth can be placed entirely in the index with confidence. When making such an index, it is also a good idea to record the anterior teeth in the index. This will provide an improved stability to the cast in the index during the remounting. Once the teeth are reset, the wax denture can be tried in the patient’s mouth to assess the accuracy. The patient is then asked to sign a statement indicating that he accepts the positions and the aesthetics of the anterior teeth and then taken to the cashier to pay at least one half of the cost of the dentures before they are processed.

35 Loosen the condylar locks. Set the teeth in the index.
If the teeth do not contact the index exactly, remount the mandibular cast. Loosen the condylar locks. Set the teeth in the index. Drop the pin so that it contacts the table. Tighten the set screw. Remove the mandibular cast. Lock the articulator in centric. Remount the mandibular cast to the new record. Raise the pin so the teeth contact. Tighten the set screw at that point. If the teeth contact the index exactly when it is replaced on the articulator, then the casts are mounted correctly. If not, the set screws of the condylar guide are loosened and the teeth are positioned to fit exactly in the index. The incisal guide pin is dropped to touch the incisal guide table and the lower cast is removed from its mounting. The teeth are replaced in the index, the set screws are tightened, and the cast remounted at this vertical dimension. When the index is removed, the guide pin is reset at zero and the vertical dimension should be correct. The mandibular teeth are now reset against the upper teeth and the denture is again tried in the mouth to assess the relationship.

36 Function Evaluate: Vertical dimension Space available for
tongue, lip-support, etc.

37 Esthetic Try-In Use of a small amount of denture adhesive is
In the clinic, we use a powder adhesive. This needs to be put in the baseplate or denture after wetting the inside then the powder is spread by holding it over the sink and shaking it briskly side-to-side. The powder is made into a paste by dabbing it with a wet finger and the denture/baseplate is inserted in the wet mouth and held in place for a few seconds. Use of a small amount of denture adhesive is helpful in building patient’s confidence at the try-in stage.

38 Observe Maximum Intercuspation
Centric occlusion in the mouth should look exactly as it does on the articulator. If it doesn’t correspond completely, the mounting is wrong and a new centric relation record needs to be made and the mandibular cast remounted. Centric occlusion should correspond with articulator.

39 Lip Support Should Come From Labial Surfaces of Anterior Teeth.
These pictures are computer-enhanced. The labial support of the teeth also pertains to the flange. A patient will not be used to having a flange and the added bulk will give the patient a profile that will seem strange. For this reason, a patient may request that the flange to be removed or thinned to the point that it is extremely fragile. This increase in the patient’s profile must be explained before the denture is made and reinforced during the wax try-in and insertion phases. The teeth must not be set back on the ridge or the flange will become more noticeable. This becomes a particularly grievous problem when the maxillary ridge extends out in front of the labial vestibule and especially with a skeletal Class II patient. A B Denture provides lip support in B as compared to A, leading to recovery of patients natural appearance.

40 Proper contouring of dentures can significantly
improve the physical appearance of the patient. These are computer-enhanced pictures and not pictures of an actual patient. The flip side of the coin is that when a patient has lost a considerable amount of the supporting bone of the ridges through trauma or resorption, normal facial contours can be restored by the denture flange, giving the patient a more youthful appearance because certain wrinkles associated with the aging process will seem to disappear. This is anticipated and often looked forward to by a patient who has had dentures for several years.

41 Evaluate The Relation Of Mandibular Teeth In Relation To Lower Lip.
It is very important that denture be in harmony with the lower lip. If the teeth are not set properly or the labial flange is too long, the lower lip will raise the denture during eating and speaking. This is the main reason that we don’t flare the mandibular teeth forward in an effort to improve the anterior occlusion in a class II patient. Mandibular anterior teeth should be positioned to contact lower lip.

42 Evaluate Cheek Contact.
Likewise, the lower denture must be in harmony with the tongue. It the mandibular posterior teeth have been missing for some time, the tongue will have grown to a very large size to fill the space it was afforded. The patient will have formed a bad habit of pressing the food against the palate, so along with it’s increased size, it has also gotten stronger. The teeth need to be set over the ridge for improved stability, but the tongue will have become such an overpowering muscle that the cheeks and lips have been crowded and the neutral zone has shifted to a more buccal position. When a new denture is placed, the patient will feel that the tongue is crowded and may very well never wear the lower denture. The patient needs to be assured that the tongue will shrink in size given a proper amount of time, and to expect a few episodes of the teeth biting the tongue. The key to the success of a lower denture in a patient such as this is persistent practice and a strong emphasis on aesthetics. Teeth Should Be in Muscular Balance Between Cheeks and Tongue (Neutral Zone).

43 Evaluate Position of the Teeth
Relative to the Tongue. The tongue may also rise above the occlusal surfaces of the teeth. This will make it very prone to getting in the way when the patient takes a bite of something. Through diligent practice, the patient will develop a new awareness as to where the tongue is at all times in relation to the denture. This awareness is called an “ingram”. The tongue will need some time to shrink back to fill this space, but it didn’t overdevelop in a short period of time, so the patient should be cautioned to allow sufficient time for it to shrink to fill the space. Difficult to evaluate

44 Golden Proportion Mona Lisa Nature is asymmetric, but proportionate
Things occurring in nature are seldom ever bilaterally symmetrical, however the more symmetrical an object appears, the more aesthetic it is to the observer. Also, things in nature are more aesthetic if their parts are in proportion to one another. Achitects, artists, and engineers have used this premise for centuries when they design their work. Parthenon Great Pyramids

45 Golden Proportion Following this line of reasoning, the maxillary anterior teeth are esthetically related to one another by a ratio of to 1. In other words, as we view the teeth from anterior to posterior, the amount of teeth visible become progressively smaller in width by a ratio of to 1. An accordion devise used to measure this relationship will demonstrate that this same relationship exists between the height of the tooth above the crest of the interdental papilla as related to the amount below the crest. When viewed from the front each tooth differs from its neighbor by a ratio of to 1.

46 Esthetics Patient Approval/Acceptance
Standard setting & contouring Recontoring Selective grinding or rearranging of the teeth can provide a much more lively and more natural appearance. Teeth may need recontoured to permit a proper overlap or contact. Get patient approval before you characterize anterior teeth. Selective grinding or rearranging of the teeth can provide a much more lively and more natural appearance. Teeth may need recontoured to permit a proper overlap or contact. Get patient approval before you characterize anterior teeth.

47 A patient may desire to have a diastema placed in the same location that his natural teeth had a diastema. One problem that is inherent to a diastema is that food debris tends to collect between the teeth, therefore the patient must floss the dentures to get it out. This must be explained to the patients at the wax try-in appointment. Standard arrangement Diastema

48 Crowding of the teeth may be desirable for the same reason.
If we crowd or overlap the teeth, the problems of keeping the teeth cleaned are increased, as calculus will tend to form on dentures much as it did on the natural teeth. Overlapping the teeth can also create problems in establishing a bilaterally balanced occlusion. This must also be explained to the patient in great detail and a signed statement must be placed in the record pertaining to the fact that the patient has been encouraged not to get overlapping teeth due to the difficulty in keeping them clean. Overlapping Mesiolingual rotation

49 All these characterizations provide the patient with a youthful appearance.
Anterior setup follows the lip line Pointed canines Large incisal embrasures In an aesthetic setup designed to make a patient look more youthful, the anterior teeth must follow the contour of the lower lip and the canines need to be pointed and located at the corners of the mouth. Large incisal embrasures will also give a youthful appearance to the patient. Worn down teeth tend to give an older age look to a patient.

50 Texture What do you see? Look closely at the texture of the gingiva.
Attached gingivae – orange peel texture Attached mucosa - smooth Orange Peel Stippling is done to a denture to provide a surface texture that will break up the ambient light as it reflects back from the mouth. This will have an orange peel appearance and can be done prior to the denture being processed or it can be applied to the denture after it is polished. Laboratory technicians tend to prefer applying this stippling effect to the denture after it is polished as stippling on a denture wax-up tends to collect stone debris during processing or will be eliminated in the final polish procedure. Smooth The denture wax-up is contoured to resemble natural tissue by festooning and stippling the wax.

51 Check working (A) and balancing. (B)
Wax-Up Should be finished and neat before seating the patient. Wax to ideal contour. Do not over-polish. (minimal polish of areas around teeth) Check working (A) and balancing. (B) Since the wax try-in appointment of a denture involves the patient’s approval of the aesthetics, the denture should be fully waxed up with all the teeth set, including the posterior teeth. This also allows the occlusion to be evaluated and the vertical dimension to be assessed. Also evaluate the plane of occlusion, the midline, the color and mold of the teeth and the horizontal overlapping of the posterior teeth as the patient functions. If only the anterior teeth are set, phonetics and function cannot be evaluated, and the patient will have to be recalled for another appointment to evaluate these aspects. A B

52 Note the contour of the vermillion border region.
Facial support affected by: Position of the incisal edge Thickness and contour of the labial flange Gingival contours Without teeth With teeth The position of the teeth and the flange also provide facial support, so it is necessary to evaluate these aspects as well. Lip support is also provided by the contours of the gingiva, which is established by the festooning of the denture. Particularly note the relationship of the vermillion border of the lower lip to the upper lip. Note the contour of the vermillion border region. These pictures are computer-enhanced.

53 What do you see in this setup?
Rotated right cuspid Pointed right lateral incisor Distal incisal edge of the right central has been recontoured Left cuspid is pointed Mesiofacial rotation of the left lateral Incisal edge of the left central has been flattened What do you see in this setup? The right cuspid is rotated lockwise and tucked in behind the right lateral incisor. The right lateral incisor appears pointed and the distal incisal edge of the right central has been recontoured. The left cuspid is pointed and the left lateral has a mesiofacial rotation so that it overlaps the central incisor slightly. The incisal edge of the left central has been flattened. All these things tend to give the patient a class II, Division 2 appearance.

54 Posterior Palatal Seal
Posterior Nasal Spine Velum This is a section cut from a cadaver that shows the tissues in the maxilla and palate. The area between the dotted lines represents the area in which a posterior palatal seal would be placed. The seal will be placed over the glandular zone and just in front of the posterior nasal spine. Glandular tissue

55 Make points in the fovea palatina area and the hamular notch areas
Make points in the fovea palatina area and the hamular notch areas. Connect these points with a solid line. Place points in the glandular area 5-8 mm forward of this first line and about two mm anterior to the line at the mid palate. Draw a second line anterior to first in a butterfly pattern connecting these dots (looks like two mountains with a valley in between). To make a posterior palatal seal in a denture when a patient is not available, begin by marking points in the palatine fovea area and the hamular notch areas. Connect these points with a solid line. Place points in the glandular area 5-8 mm forward of this first line and about two mm anterior to the line at the mid palate. Draw a second line anterior to the first in a butterfly pattern connecting these dots wnich looks like two mountains with a valley in between.

56 It should feather out to zero at the anterior line.
Carve the seal with a cleoid/disoid &/or #7 spatula or the back of a green-handled knife (best). It should be .5 mm deep in the middle of the posterior palate, 1 mm deep in the hamular notch area, and 1.5 mm deep in the glandular area between the hamular notch and the middle of the posterior palate. It should feather out to zero at the anterior line. It should not extend onto the tuberosities or onto a torus. Carve the seal with a cleoid/disoid carver, a #7 wax spatula, or better yet, the back of a green-handled knife. It should be .5 mm deep in the middle of the posterior palate, 1 mm deep in the hamular notch area, and 1.5 mm deep in the glandular area between the hamular notch and the middle of the posterior palate. It should feather out to zero at the anterior line. It should not extend onto the tuberosities or onto a torus.

57 *These procedures must be performed in the sequence listed above.
Check off list Check vertical dimension of occlusion and vertical dimension of rest. Prove centric relation record. Make protrusive record. Evaluate esthetics and phonetics. Mark the posterior palatal seal. *These procedures must be performed in the sequence listed above.

58 Questions?


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