C LINICAL S CIENCE

A Case Study: Esthetic & Biologic Management of a Diastema Closure Using Porcelain Bonded Restorations for Excellent & Predictable Results

D OCTOR’ S P ERSPECTIVE

I NTRODUCTION One of the clearest indications for porcelain-bonded restorations is diastema closures. Veneers can make a dra- matic improvement to the appearance in the smile with undersized teeth in an oversized arch (Figs 1 & 2). Before we had the ability to bond porcelain veneers to the teeth, these types of cases were practically untreatable. by by Although the occlusion often is ideal in diastema cases, Lynn A. Jones, D.D.S. Michelle Y. Robinson the teeth are too small for the size of the jaw. Orthodontics can only rearrange the spaces. Composites Dr. Lynn Jones received her Michelle Robinson specializes in might work but would be less predictable in large can- DDS from the University of esthetic and reconstructive cases tilevered spaces between worn teeth, and composite is Washington and is now recog- fabricated from a full range of nized for both her excellent cos- restorative materials. An active more difficult to control where deep subgingival margins metic dentistry and innovative member of the American are necessary for esthetic emergence profiles between the management practices. She is an Academy of Cosmetic Dentistry, teeth. The other option, porcelain crowns, would have accredited member of the her goal is to help develop new required excessive reduction of otherwise healthy teeth, American Academy of Cosmetic materials to solve esthetic and and with dubious esthetic results. Dentistry, has served on the reconstructive needs. As a clini- Well-controlled bonded porcelain restorations can pro- board of directors and is current- cal instructor for Team Aesthetic duce beautiful results while preserving the strength of the ly an accreditation examiner. Seminars, she has gained a great original tooth. If the guidelines for good smile design and Dr. Jones has spoken on Micro deal of experience teaching clini- tooth preparation are combined with occlusal manage- dentistry at the AACD, WSDA cal programs with Dr. David and other meetings. She is the Hornbrook and Dr. Thomas ment, veneers can look, feel, and function like healthy director of "Aesthetics Trinkner. Her desire is to share natural teeth. Continuums" for the University her knowledge with students and A smile with a high lip line and large spaces poses some of Washington CDE focusing on help propel them forward in their special challenges. Careful attention to the details of cosmetic and reconstructive den- quest for excellence. interproximal emergence profiles, biologic width, and tistry. Dr. Jones maintains a pri- papillary height is necessary to get excellent results. If the vate practice in Bellevue, teeth are worn or if the spaces are wide, the teeth will Washington. appear to be disproportionately short and wide after the

72 THE JOURNAL OF COSMETIC DENTISTRY • FALL 2002 VOLUME 18 • NUMBER 3 Figure 1: Pretreatment diastema undersized Figure 2: Veneers can make a dramatic teeth relative to the size of the arch. improvement to the appearance.

Figure 3: Pretreatment smile. Figure 4: Pretreatment maxillary left lateral.

diastemas have been closed with or the apex of the gingival scallop is PATIENT’ S C ONCERNS restorations. The apparent height to out of alignment because a tooth is out The patient wanted to close the width ratios can be managed to some of position, it can make it impossible spaces between his teeth (Fig 3); he degree by artistically controlling to achieve the correct gingival archi- wanted very white teeth with no reflective and defective surfaces. It also tecture. In an esthetically sensitive unsightly amalgam restorations; and is possible to increase the actual length patient, even a slightly asymmetrical he did not like his flat, worn canines of the tooth a limited degree by papilla can be a concern. With proper (Figs 4 & 5). He is an esthetically sen- extending it gingivally when com- planning and understanding of the sitive patient with a high lip line. The bined with a crown-lengthening pro- biologic and esthetic rules of soft tissue spaces on the lower left were almost as cedure, and incisally until it interferes management, these issues can be pre- much of a concern to him as the spaces with the envelope of function. In dicted and controlled. The purpose of in the upper anterior (Fig 6). He also extreme cases the entire vertical this article is to use a case study to was somewhat concerned about the dimension of occlusion may need to be show how to overcome these obstacles worn incisal edges. He had consulted altered to achieve the desired length. with careful planning, soft tissue man- with an orthodontist, who had advised The mesiodistal tooth position agement, attention to occlusion, him that his teeth were too small to itself is another consideration, espe- preparation design, laboratory commu- completely close the spaces with tooth cially in a case where there is a high lip nications, and excellent porcelain movement. line. If the spaces are not symmetrical work.

VOLUME 18 • NUMBER 3FALL 2002 • THE JOURNAL OF COSMETIC DENTISTRY 73 Figure 5: Pretreatment maxillary right Figure 6: Pretreatment mandibular left lateral. lateral.

Figure 7: A level stick-bite. Figure 8: Pretreatment retracted anteriors.

DIAGNOSIS AND To achieve the desired results, the (Pitsburgh, PA). Three different T REATMENT P LAN teeth would be whitened first with an designs of varying lengths were pre- in-office whitening system. All of the sented to the patient to gauge his The patient’s medical history was conservative Class I amalgam fillings expectations and clarify his esthetic noncontributory. He is 42 years old would be replaced with direct compos- desires. It helped to determine and has a healthy dentition with no ite. Teeth 4–13 and 21–28 would be whether we should design a flat smile caries and good periodontal health; 3 restored with reverse /4 porcelain- or one with more contours; and how there are preexisting amalgam restora- bonded restorations. long he wanted his teeth. From the tions on ## 2, 3, 4, 18, 29, and 31; and There are various methods for imaging, the patient immediately preexisting composite on ## 14 and developing the smile design, including rejected longer teeth and expressed a 15. Teeth 13 and 19 have preexisting full intraoral mock-ups done directly desire for pointed canines. He also endodontic treatment and crowns. All on the teeth, or mocking-up the max- agreed that wider incisal embrasures four wisdom teeth are missing. illary central incisors only and then looked better. Moderate wear was noted on the ante- doing the diagnostic wax-up. To design Once a smile design is selected from rior teeth. Diastemas ranging from 0.5 the smile for this case I chose to use the image, the necessary records are to 2.5 mm are located between almost computer imaging and laboratory- made for a preliminary wax-up. The every tooth anterior to the first bicus- made wax-ups. laboratory will need specific informa- pids. There are no signs of temporo- tion to give the best result. If the mandibular disorder (TMD) and the The original smile design was devel- occlusion is going to be equilibrated, occlusion is Class I normal with large oped with computer imaging using the this is the easiest time to do it. In this diastemas Image/FX program from Sci-Can

74 THE JOURNAL OF COSMETIC DENTISTRY • FALL 2002 VOLUME 18 • NUMBER 3 Figure 9: Midline placement. Figure 10: Facebow. case the equilibration was not indicat- black holes and avoiding the peri- causes an unnatural gingival contour ed, so the bite registration was made in odontal biologic width. Note that the and a very boxy looking tooth. If the centric occlusion. A level earbow was interradicular distance can influence gumline recedes to reveal the margin made for the Artex articulator the distance between the interproxi- of the veneer with its obvious over- (Girrbach Dental; Pforzheim, mal contact and the alveolar crest. A hang, the esthetics will be ruined. If Germany) a level stick-bite was made, depth of 5 mm or less is necessary to that is the case, it would preferable to and both recordings were confirmed guarantee that the papilla will fully rearrange the spaces with orthodontics with a photograph (Fig 7). A “before” occupy the gingival embrasure space1 so that they are distributed evenly smiling photograph and the selected based on roots that are 2.5 mm apart. between all of the anterior teeth prior image were included with written In this case, the sounding depth to veneering. Evaluate the shape of the instructions for the desired overbite between teeth 8 and 9 was 4mm and teeth and the size of the spaces. If the and overjet and desired tooth length the interradicular distance was 3.5 coronal portion of the tooth is not (computer photos are not 1:1). mm. That meant the contact point much wider than the root (as we see in should be no more than 4 mm from the this case) and the spaces between the alveolar crest. teeth are under 3 mm, the contours of D ETERMINING THE the crown should appear to be normal. D ESIRED P OSITION OF For example, if the sounding depth THE I NTERPROXIMAL were 3 mm, space closure would be C ONTACT more difficult because this patient has G INGIVAL A PEX a naturally narrow biologic width. On the preparation day after the Gingival contours are distorted That means the contact point would patient has been anesthetized, the when the tooth is made wider to close be moved to within 3 mm of the interproximal depths are sounded to a space. The apex of the gingival mar- osseous crest; if it were placed 4 mm determine this specific patient’s bio- gin will not move even if you perform above the alveolar crest it would result logic width of tissue and how deep the a crown-lengthening procedure.3 The in a black triangle. A sounding depth margin can be placed to establish the apex will always be over the root of 5 mm may mean that there is a long proper emergence profile. This also prominence. If this is not acceptable epithelial attachment. Placing a deep helps determine the point where the then the tooth will have to be moved margin may result in recession and loss proximal contact should meet. A bio- by orthodontics. of papilla. If the contact point is made logic width of 2.5 mm or more is nec- at 5 mm, in this example, it is likely to In this particular case, #8 is tilted to essary to prevent a violation that caus- leave a black hole. So it is still a good the distal but the gingival apex of the es chronically red and inflamed gingi- idea to make the contact 4 mm from crown is very close to the proper posi- va. To create the desired emergence, the alveolus.2 tion (Fig 8). This made it possible to the margin must be placed as far below veneer the tooth without orthodonti- Very wide diastemas over 4 mm the tissue as possible. In most cases, 1 cally repositioning it. Had #8 been in require an extreme alteration of emer- to 1.5 mm is ideal for controlling the the same position with the root verti- gence profile approaching 90°. This

VOLUME 18 • NUMBER 3FALL 2002 • THE JOURNAL OF COSMETIC DENTISTRY 75 Figure 11: The teeth can be made to look Figure 12: The teeth can be made to look narrower by decreasing the area of the smaller and narrower by tapering the incisal reflective surface. angles towards the tooth and the opening the embrasure.

Figure 13: Placement of the interproximal Figure 14: Closing black holes/emergence contact. profile. cally above it, the apex of the gingival to many cosmetic-veneering proce- increase the scallop, where the osseous scallop would have been in the wrong dures. About 80% of the population and gingival architecture around wide- place and the midline papilla would have some gingival display. The transi- ly spaced teeth tend to be flat. have been asymmetrical. In that case, tion from the tooth to the gingiva minor tooth movement or reposition- poses one of the most challenging cos- M IDLINE AND G OLDEN ing the dental midline with porcelain metic problems when closing P ROPORTION to compensate for the asymmetry diastemas. A gum lift serves a dual pur- would be required. pose: it improves the height-to-width M IDLINE ratio of a short, wide tooth; and it A line connecting the lowest point helps to lengthen the taper of the gin- G UM L IFTS of the V in the upper lip with the mid- gival scallop around the necks of line of the lower incisors defines the Another way to control the emer- square looking-teeth. midline (Fig 9).4 Locating the midline gence profile and create a more desir- A gingivectomy gives a longer run varies from one case to the next and able height-to-width ratio is to do a at the interproximal emergence profile sometimes, for various reasons, we gum lift. A “gum lift” by either a gin- so the gingival contours look smoother choose to ignore it. More important givectomy alone or combined with and more tapered rather than coming than the location of the midline is the osseous recontouring of the facial sur- out at a right angle to the proximal degree of cant. Variance in the face has become an essential adjunct wall of the tooth. The goal is to mesiodistal position of the midline is

76 THE JOURNAL OF COSMETIC DENTISTRY • FALL 2002 VOLUME 18 • NUMBER 3 Figure 15: Closing black holes/margin Figure 16: Post treatment retracted right placement. lateral.

Figure 17: Post treatment retracted left Figure 18: Post treatment retracted lateral. anteriors. not generally noticeable. A midline with a level on the earbow and a pho- patient’s face was very symmetrical and cant, however, generally is the most tograph to confirm the relationship of all of these guidelines indicated the visible distraction from the esthetics of the earbow to the face. Several refer- same vertical line. A stick-bite with a an otherwise normal healthy smile.4 ence points have been suggested to photograph is used to confirm the face- To obtain a record of the vertical determine the true vertical in the bow recording and give the laboratory midline, a facebow for an Artex artic- patient’s face. Different elements come another point of reference for ensuring ulator was made over the prototype into play depending upon the patient. a vertical midline. With these two restorations (Fig 10). Before the face- The interpupillary line is perhaps the pieces of information, the laboratory is bow recording was set the patient was most frequently used reference but it able to mount the case on an articula- asked to stand straight. The ear-bow has drawbacks because the eyes often tor with the occlusal plane and smile has a little play inside the ear and the are not level. It also has been suggest- line oriented in the right plane. The universal joint, which connects it to ed that a line connecting the exact stick-bite is made over the final proto- the bite-fork, moves freely. The ear- center of the bridge of the nose and type restorations to give the horizontal bow is attached to the bite-fork, which the center of the labial filtrum repre- orientation of the smile line and also is securely positioned on the teeth sents the best vertical line; another to indicate the incisal edge position of with a maxillary bite registration so suggestion is to use the horizon or a the provisional restorations. The stick- that it remains stationary. While the level to determine true vertical in the bite is made by spinning a stick (a dis- patient was standing with his head smile. Like many artistic decisions, posable paintbrush works) into the soft level, the front of the earbow was judgment will guide which of these registration material at the incisal edge maneuvered into a line parallel with guidelines is most useful in an individ- of the upper centrals while the patient the floor. This position was confirmed ual case. In this particular case the bites in centric occlusion.

VOLUME 18 • NUMBER 3FALL 2002 • THE JOURNAL OF COSMETIC DENTISTRY 77 Figure 19: Post treatment lower left. Figure 20: Post treatment smile.

G OLDEN P ROPORTION The apparent size of the tooth is P REPARING THE T EETH identified primarily by the reflective The ratio of the centrals to the lat- To esthetically close a diastema the surface, that is, the surface that reflects erals in this case is 1:6.9, or very close interproximal contact is placed more light back into the eye of the viewer. It to Golden Proportion. The ratio of the to the lingual (Fig 13). By moving it does this because that surface is per- laterals to the canines is 1:0.88—a lit- lingually it creates a larger embrasure. pendicular to the line of sight and tle further from Golden Proportion but This is how the greater deflective sur- directs the light straight back to the not enough to be a distraction from face areas are created, thus making the viewer and appears brighter. The the harmony of the smile design. The reflective surfaces appear narrower. deflective surfaces direct the light ratio of the canines to the first premo- This technique is also useful in giving away from the viewer’s eye and cause lar is 1:0.75, once again close to the teeth more relief if the esthetics that part of the surface area to recede. Golden Proportion. The importance of appear flat and lifeless. Golden Proportion has been much In this case the actual height-to-width Another problem with diastemas is debated and has been demonstrated to ratio is 1.0:0.9 on the centrals, but the that the papillae are usually flat. This be the exception more often than the reflective surfaces are 1.0:0.7. leads to the dual challenge of creating rule.5 It is helpful to use as a guide if Controlling the light this way makes a pointed papilla and completely clos- something doesn’t look right, but very these central incisors appear narrower ing the little black holes in the gingi- few anterior teeth are arranged exactly than they actually are, just like the val embrasure (Fig 14). If the contact in Golden Proportion. rectangle on the right in the previous illustration. Yet both rectangles are is extended gingivally and toward the More important than Golden exactly the same size. lingual it can be used to create volume Proportion is the symmetry of the with the porcelain, which will then Another way to make the rectangle teeth and harmony with the face and push the papilla forward and incisally look narrower is to physically take smile. The facial of 6 and the distal of into the gingival embrasure on the parts away. Rounded incisal angles cre- 8 and 10 were out of alignment (Fig 3). facial of the contact. This will help to ate an optical illusion that causes the To achieve symmetry, those surfaces prevent little black holes in the gingi- tooth to appear narrower by drawing were contoured to be parallel with the val embrasure and make the papillae they eye toward the center of the distal contours of the remaining teeth look longer and more pointed. prior to preparing the teeth for porce- tooth. Also, the tooth is actually nar- If the sounding depth is only 3 mm lain. rower in the incisal region, which helps to reduce excessive bulkiness. To the margin cannot be placed more make the tooth look narrower, the than a half millimeter below the tissue. C ONTROLLING I LLUSIONS incisal edge has been tapered in to a A deeper margin could potentially vio- Are these rectangles the same size? They ratio of 0.7:1.0, similar to the rectangle late the biologic width of the peri- illustrate the next principle in illusions for in the illustration (Fig 12). odontium. In a case like this the emer- creating esthetic space closures (Fig 11). gence profile would have to be almost perpendicular to the interproximal

78 THE JOURNAL OF COSMETIC DENTISTRY • FALL 2002 VOLUME 18 • NUMBER 3 Figure 21: Post treatment right lateral view. Figure 22: Post treatment retracted anteriors. wall of the tooth and the contact might not be able to completely close L AB T ECHNICIAN’ S would have to be very long. This is eas- the little black hole. P ERSPECTIVE ier to do with circumferential veneer Combining all of the elements of but a reverse 3/4-veneer design works planning the diastema closure smile if the margins are placed well to the design, correct preparation design, I NTRODUCTION lingual of the contact area (Fig 15). proper margin placement, adequate Diastema cases present many The margin of the veneer must be placed tooth reduction, beautiful porcelain esthetic challenges. One of the chal- apical and lingual to the papilla, as shown contours, color, and surface texture, we lenges for the ceramist in this situation in the two images on the left (Fig 13). were able to achieve the excellent comes when the restorations appear results illustrated in this article (Figs The apparent contact area should too wide or out of proportion (ideal is 16-22). be about 50 percent of the full length 75 percent width-to-length ratio on ______of the central incisor. The preparation centrals). We are able to control what ® appears to be the width of the tooth by design for d-SIGN (Ivoclar/Vivadent; References exaggerating the deflective areas and Amherst, NY) porcelain should allow 1. D Tarnow, AW Magner, P Fletcher. The effect of a thickness of 0.5 mm at the gingival distance from the contact point to the crest of minimizing the reflective area (facial) margin, 0.7 mm in the mid-body and bone on the presence or absence of the inter- of the tooth/teeth. To do this, the con- proximal dental papilla. J Periodontol 63(12):995- tacts must be moved to the lingual of at least 1 mm in the incisal third to 996, 1992. the interproximal surface and the prevent dentin shine-through and to 2. JC Kois, RT Vakay. Relationship of the peri- conceal the silhouette of the prepara- odontium to impression procedures. embrasures must be opened to allow tion under the porcelain. Compendium, 21(8):684-692, 2000. for light illumination. If the embra- 3. C Townsend, Resective surgery: An esthetic sures are not opened enough the If the margin is placed too far to the application. Quintessence Int 24(8):535-542, tooth/teeth will look “square” or labial several problems occur. First, the 1993. “boxy” and the food will trap near the laboratory technician will not have 4. VO Kokich Jr., HA Kiyak, PA. Shapiro. papilla, resulting inevitably in enough room to create a deep labial Comparing the perception of dentists and lay unhealthy tissue. After moving the embrasure and large deflective surfaces people to altered dental esthetics. J Esthet Dent 11(6):311-324, 1999. contacts lingually and filling the to visually narrow the tooth. Second, 5. JD Preston, The Golden Proportion Revisted. “black triangle” spaces with porcelain, the margin of the porcelain will pro- J Esthet Dent 5(6):247-251, 1993. we sometimes are left with small can- trude from the gingival-axial wall, cre- ______tilever pontics that appear to be part of ating a plaque trap. The emergence the tooth. These ledges are easily profile from the gingival margin must maintained if constructed properly. be almost 90° and near the labial sur- face, causing an unnatural gingival Upon laboratory receipt of the case, contour—and the technician still the communication letter is read and

VOLUME 18 • NUMBER 3FALL 2002 • THE JOURNAL OF COSMETIC DENTISTRY 79 Figure 23: Incisal matrix made from putty Figure 24: Soaking of refractory dies prior for incisal edge position. to porcelain application.

Figure 25 Application of undiluted dentin in Figure 26: Fired refractory dies. lobe formation to create base structure. the case is logged in, while ensuring split-cast system. The pinned models P ORCELAIN W ORK B UILT that all items needed to complete the are sectioned into individual dies, but IN d.SIGN PORCELAIN case as requested are included. All before the dies are replaced in the base When reviewing a diastema case items that need to be disinfected are the adjacent pinned teeth and all bases before starting porcelain application processed according to OSHA require- are polished. All models are mounted, there are several things that need to be ments. The case is then sent to the cross-mounted, and polished again. addressed: model department for the impressions The ceramist reviews the case and the to be worked-up. Before the stone doctor’s requests. Refractory work is • Where have the contacts been models are trimmed the accuracy of then done. The success of any refractory placed in the provisionals? the stick-bite is verified with the case depends heavily upon the level of • Are there “Black Triangles” included photos. The maxillary model refractory work your lab team is capable present? is trimmed with the stick-bite on the of creating. Refractory die position is • Has the doctor. prepped slightly anterior teeth ensuring that the base of verified by an incisal matrix made from subgingival to allow for triangle the model will be parallel to the max- a solid model. Rotation or misplace- closure? illary plane. The maxillary model is ment of any die will be detected and/or • How wide are the teeth to be trimmed to the mandibular. All other corrected at this time. built? models are trimmed in a similar fash- ion, resulting in parallel bases on all • What is the final desired length? models. One prepped model is pinned • Are the Golden Proportions and all models are based using the pleasing to the eye?

80 THE JOURNAL OF COSMETIC DENTISTRY • FALL 2002 VOLUME 18 • NUMBER 3 Figure 27: Full contour build-up. Figure 28: Creation of internal lobes using the incisal edge matrix for correct placement.

Figure 29: Layering of different internal Figure 30: Verification of the horizontal effects. plane of the restorations.

This is where the provisional almost any case. What color(s) are the The refractory dies are soaked in restorations come into play. Models of prepared teeth (i.e., Is there any mask- water prior to any porcelain applica- provisional restorations (as well as ing that needs to be done to achieve tion (Fig 24). Neutral or clear porce- photos of them) are necessary when the final desired color of a B-1)? lain is applied in a small crescent building a diastema case. They answer Luckily, the prep shades in this case are moon area at the margin. This will all of the above questions and provide ideal, which leaves many options. allow the restorations to blend well a 3D visual to work from. Should the upper or the lower be built with the natural dentition when seat- By placing the maxillary provision- first? Should they be built simultane- ed. Undiluted dentin shade is placed al model on the articulator with the ously, as the preps are opposing each over the rest of the prepped areas, with mandibular model, it is possible to other? It is best to try to choose the lobe formations extending over the make an incisal edge matrix of the simpler way to avoid problems. The edges of the preps (Fig 25). The dies maxillary against the mandibular choice here is to build the lower are then fired (Fig 26). The dies are model (Fig 23), thus providing the restorations to full contour (pre-glaze) cooled, soaked again in water, and incisal edge position, tooth width, and before starting the upper units. I build placed back into the water reservoir final veneer length. Again, the in several layers and fire many times to matrix. A dentin/neutral mix is ceramist’s artistry can enhance what have the most control over the final applied as a full contour in the gingival has already been established. result. By carefully planning the build- half and as full contour lobing (using Provisionals take the guesswork out of ing strategy it is easier to avoid making the upper provisional model as a internal mistakes. guide) on the incisal half. The dies are

VOLUME 18 • NUMBER 3FALL 2002 • THE JOURNAL OF COSMETIC DENTISTRY 81 Figure 31: Restorations prior to final polish Figure 32: Porcelain added to embrasure and devesting. area to correct a potential “black triangle”.

Figure 33: Final polish with a soft brush Figure 34: Completed restorations on solid and porcelain polishing paste. model. fired again. Satisfied that the develop- tion of salmon and light mammelon with diluted dentin in deficient areas mental lobe placements are correct, it porcelains. These are difficult to apply on gingival half and a variegated E1, is now time to build in internal effects. but add greatly to the final beauty. A E2, and TS1 across the incisal edge Effects are not created from surface very wet liner brush with a heavily (Fig 27). The dies are fired again. After staining. E3/E4 mix (Ivoclar/Vivadent; diluted mammelon effect is dragged checking contacts and occlusion, the Amherst, NY) is placed on the mesial, down the incisal surface of wet porce- contours are finalized. Surface mor- distal, and middle lobes, extending lain. The dies are then fired again. phology is emphasized. If any add-ons slightly beyond the fired dentin in a Shade is constantly monitored are needed, they are applied with finger-type effect. A yellow-gray finger between each firing. It is important to either an E2 or neutral, depending is placed slightly off-center on the note that up to this point the contacts upon the area. middle lobe for additional characteri- between each tooth are either open or Moving onto the maxillary arch, zation. An E3 high-value band is loose. It is easy to overbuild, resulting the units are built in a similar fashion. added horizontally between the gingi- in mispositioning a die if the contacts Contacts are built to the lingual, and val and middle thirds and a khaki is are binding. When these are placed the deflective angles of the teeth are applied sparingly (because the desired back into the reservoir matrix the broader to make each tooth look nar- final shade is so light) on the cervical effects are evaluated; these can be rower. The key here is to keep the neck area. Before firing, the final inter- sharpened with a mini-diamond disk if transition between the reflective and nal touch is added in an almost “water- any of them appear to run together. deflective angle smooth to avoid harsh color” fashion using a watery variega- Next, teeth are built to full contour light reflection that results in an

82 THE JOURNAL OF COSMETIC DENTISTRY • FALL 2002 VOLUME 18 • NUMBER 3 unnatural look The incisal matrix until slightly dull, with particular groups, adjusting any contacts neces- made from the provisional restorations emphasis on the high areas of the lobes sary; and then all together to ensure is used as a guide to determine where or the areas of the lobes that the lips that orthodontic placement is correct. to build the lobes and (of course) tooth continuously rub on. Next, using a A tacking material under the veneers width and length (Fig 28). When Robinson™ bristle brush (Buffalo keeps them in place during final check building the maxillary units the same Dental Mfg. Co.; Syosset, NY) with of occlusion and excursive move- steps are followed, with the exception Dia-Shine Fine grit (VH Techno- ments. Veneers are transferred to the of heavier internal effects with more logies; Bellevue, WA), polish is repeat- solid models to note any corrections incisal porcelains to create more edly worked over the restorations until (Fig 34). If any corrections need to be incisal characteristics (Fig 29). The the polish has disappeared (Fig 33). made then the d-sign km is applied stick-bite is clipped onto the lower The veneers are steamed and ready to and the units to be fired are placed on model to be used as a guide for a cor- be devested. Devesting is a simple the firing tray with an instant refracto- rect horizontal plane as well as a per- process using glass beads at 60 to 80 psi ry material such as Vest-It (Green-Kel pendicular midline (Fig 30). to blow the refractory material away Innovations Inc.; Cranberry, PA) If Periodically during the incisal porce- from the veneer. Any overhangs or the program temperature is not too hot lain application all excursive move- over-extensions on the margins are then there is very little chance of any ments are checked against the lower carefully removed using a diamond- warping. Finally, the all-on is refined units to ensure that proper function impregnated wheel. Restorations are with a rubber wheel and diamond-pol- and occlusion have been established. ready to be fit to the master dies. If the ished as before. The case is complete Once all of the restoration contours refractory work was done well, then and the quality check is done before it have been finalized all units are glazed. fitting time should be minor. If there is is sent back to the doctor. Contacts are checked again using a a bit of hesitation to a restoration seat- ______Mylar strip for consistency. Black tri- ing, then fit-checker spray is a handy ❖ angles have been monitored through- tool. Unfortunately, refractory veneers out the building process and changes in comparison to pressed ceramic are made prior to final polish (Figs 31 veneers are more fragile to fit; great & 32). care must be taken not to chip or frac- Final polish is an important step. A ture the restorations at this point. All beautiful, natural luster is achieved by dies are placed back into the base and first rubber-wheeling the restoration the veneers are tried-in, first in small

VOLUME 18 • NUMBER 3FALL 2002 • THE JOURNAL OF COSMETIC DENTISTRY 83