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Dental Tribune Middle East & Africa Edition

AuthorsLorin Berland, DDS, FAACD, and Sarah Kong, DDS T he name of the game in dentistry to- day is to save the tooth for use in the future. In this age of adhesive dentistry, respecting and preserving the remaining healthy tooth structure as well as improving esthetics have become compo- nents of value as well. With today’s advanced technology and materials, longevity is mainly a matter of diagnosis, correct treatment plan- ning and proper execution of technique. The problem with replacing old amalgams with tooth-colored composites is that they are difficult, inconsistent and unpredictable. Yet, the warranty on these 30-, 40- and 50-year- old silver fillings is running out. We have to remember that amalgam technology is more than 150 years old. At that time, people lost their teeth a lot earlier and died a lot earli- er, too. Now, however, we have a population that is over 50 years old and growing – and they want to keep their teeth feeling good and looking good. Patients are now living longer and they want and expect to keep their teeth for a lifetime. Adhesive dentistry offers a more conservative restorative approach to conventional dentist- ry. Why take away healthy tooth structure when there’s a viable alternative? Why not attempt to save the good and just replace the bad? Direct composites and laboratory com- posite resin systems are valuable and worth- while options to preserve tooth structure and long-term dental health. After all, preserving a patient’s natural tooth, whenever possible, is always in his or her best interest. It has been our experience that providing multiple, large interproximal posterior com- posites directly can be difficult to achieve on a consistent basis in the oral environment, es- pecially when replacing amalgams. Why? Be- cause they take a lot of chair time. Amalgams require bulk. That’s why we were taught the block type preparation to provide the neces- sary bulk for strength. Furthermore, because amalgams do not bond, we were taught to create undercuts and “ex- tension for prevention.” As mercury contracts and expands with cold and hot temperature changes over time, cracks form in the glass- like nature of teeth. Most of the time, these large preps are diffi- cult to restore with direct composite. There are isolation and contamination issues, and it is difficult to replicate nature in the mouth in a timely, cost-effective and predictable man- ner for every case, every time. In addition, curing in layers makes for a long appoint- ment and increases the possibility of con- tamination. It is uncomfortable for patients to keep their mouths open for the prolonged amount of time necessary. Often, large direct posterior composite resins yield unsatisfactory results in terms of esthet- ics, and especially long-term function, due to curing and contamination issues. However, when we do same day inlay/on- lays out of the mouth and in the laboratory, we find that multiple posterior restorations are easier, stronger and more anatomical- ly correct. Because they are processed at the same time, they can be even more time effi- cient than using a CAD/CAM system and re- duce tooth movement during the transition- al phase that can result in altered contact or occlusion. Not having to deal with provisional restora- tions absolutely eliminates those untimely emergencies when temporaries break or come off. Those costly, non-productive, uncomfort- able and unhappy second appointments can also be avoided, saving everyone time and money. In addition, without concerns about retention of temporaries, preparation can be even more conservative. CaseNo.1 In this case, the patient came to our office on an emergency basis with a broken tooth on the upper right molar. It was no surprise that the tooth had a previously placed MO amalgam with recurrent decay that caused the mesio- buccal cusp to fracture off completely (Figs. 1, 2). Often, teeth that have had old amalgam fillings tend to break due to cracks caused by the expansion and contraction of the metal al- loy in the tooth’s glasslike substance. In addition, caries detectors were non-exis- tent when the bulk of amalgam restorations Same-day inlay/onlays strive to save the tooth mCME articles in Dental Tribune have been approved by HAAD as having educational content for CME credit hours. This article has been approved for 2 CME credit hours. 2 Hours prepared for amalgam retention. A flat-end cylinder, fine-grit, short shank diamond was used to refine the tooth preparation after in- sulation was completed (Fig. 4). Next, two Identic hydrocolloid alginate im- pressions (Dux Dental) were taken fast and accurately. They take only 90 seconds to set with our chosen materials, so they are ideal for same-day inlay/onlays. Before expressing the hydrocolloid material into the prepped tooth, we squirted a little surfactant (PrepWet Plus, Dux Dental) onto the tooth to wet the prep while my assistant mixed the alginate. Meanwhile, a second assistant was loading a syringe with warm Identic Syringable Hydro- colloid Cartiloids (Dux Dental) to hand to me. The “plug” was initially squirted away from the prep and then into the prep itself so as not to interfere with a “clean” impression. Once the tray had been loaded with the alginate (Identic, Dux Dental), the first assistant hand- ed it to me. The tray was inserted with gentle pressure and held steady for 90 seconds. An- other impression was taken using the same aforementioned steps. The patient then had about an hour break while the inlay was being made and was able to make the most efficient use of his time by having his teeth cleaned with the hygienist during this break in treatment. This not only made the time seem to go by faster for the pa- tient, but it also eliminated “dead time” in our schedule. The patient made the most of his time in the chair, fixing his broken tooth and getting his teeth cleaned. This type of combination treat- ment lends itself to a more productive day when scheduled this way, and patients real- ly appreciate it. Labwork Meanwhile, back in the lab, the impres- sions were first disinfected and then poured with MACH-SLO (Parkell) and based with bite registration material on a C- Bite articulator (C-Bite, Dental Products) (Fig. 5). An electric waxing unit was used to block out any undercuts on the die (Ultra Waxer, Kerr Lab). The onlay was incrementally built in com- posite layers with a D2 primary dentin base shade (Premise Indirect Primary Dentin, Kerr Dental) followed by an A2 facial dentin shade (Premise Indirect Facial Dentin, Kerr Dental) and a neutral incisal shade (Premise Indirect Incisal, Kerr Dental). Once the onlay was cured with light, heat and pressure in the BelleGlass curing unit (Kerr Dental) for 10 minutes, it was fitted, adjust- ed and polished on the silicone models (Figs. 6, 7) with various burs and polishing wheels. All margins, contacts and contours were easi- ly and accurately verified outside the mouth, saving valuable chair time and clinical frus- tration. Seatingtheonlay When seating the onlay, a medium size Iso- lite (Isolite Systems) was applied for easy iso- lation, suction, bite rest and illumination dur- ing the cementation of the onlay. No further anesthesia needed to be administered as the tooth had been lined with flowable compos- ite during the prep stage. Patients really ap- preciate this — especially because they are al- most back to “normal” by the time they leave. The onlay was then tried in to verify proper contacts, contours, margins and esthetics. Be- fore cementation, Expasyl (Kerr Dental) was Fig. 4 Prepped tooth, palatal view. Fig. 5 Silicone model. Fig. 6 Sectioned model. Fig. 7 Silicone model, buccal view. Fig. 8 Tooth ready to bond. Fig. 9 Expasyl placed interproxi- mally prior to seat. Fig. 10 Onlay seated, palatal view. Fig. 11 Onlay seated, buccal view. Fig. 12 #30 pre-op. Fig. 13 FenderWedge in place. Fig. 1 #3 pre-op, palatal view. (Photos/Provided by Dr. Lorin Berland and Dr. Sarah Kong). Fig. 2 #3 pre- op, buccal view. Fig. 3 Decay removed and lining placed. were placed so many teeth have recurrent de- cay under the old amalgam fillings. After thorough clinical and radiographic ex- aminations were performed, it was deter- mined with the patient’s input that a same- day onlay would be the most prudent option for this tooth. This way, he would be receiv- ing the maximum amount of care in the least amount of time. Theprocedure After placing topical anesthetic, articaine HCl 4 percent with 1:1,00,000 epinephrine was ad- ministered to achieve profound anesthesia. Next, a nitrous oxide nasal mask was placed to decrease the patient’s exposure to mercu- ry aerosol while the amalgam was being re- moved. In this case, because the patient opted not to use nitrous oxide, pure oxygen was ad- ministered through the nasal mask. We continued by isolating tooth #3 with a rubber dam. This step was essential to reduce the amount of amalgam ingested by the pa- tient. It also offers isolation, higher visibility and better dentistry for our patients. If doing quadrant dentistry, I like to use the split-dam technique, which stretches to include several adjacent teeth in a quadrant. A FenderWedge (Directa) was then placed to separate and protect the adjacent tooth during prep, air abrasion, etching, bonding and refining while continuing to wedge the teeth for a tighter in- terproximal contact in the final restoration. To facilitate removal of the remaining amal- gam restoration, an hourglass-shaped dia- mond bur was used as diamonds are less like- ly to produce the fracture and craze lines as- sociated with carbide burs. High-speed evac- uation was used throughout the procedure to help decrease possible inhalation and inges- tion during amalgam removal. Caries detector was painted onto the pre- pared surface, and it was noted that cracks associated with the long-time expansion and contraction of the mercury-filled amalgam restoration had contributed to the appar- ent interproximal decay. Once the decay was carefully and completely excavated using a small, round diamond bur and a spoon exca- vator, the tooth was insulated in a few impor- tant steps (Fig. 3). First, disinfectant was placed on the prepared dentinal surface (Hemaseal & Cide, Advan- tage Dental Products) and air-thinned. Then, two coats of self-etching bonding agent (Opti- Bond All-In-One Unidose, Kerr Dental) were placed to provide reduced postoperative sen- sitivity and high dentin bond strength. After air thinning and light curing, a flow- able composite (Premise Flowable, Kerr Den- tal) in the lightest shade was added to the in- ternal walls and floor to create an even floor and to fill in undercuts that were originally Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 12 Fig. 11 Fig. 13 Fig. 5 Fig. 6 Centre for Advanced Professional Practices (CAPP)is an ADA CERP Recognized Provid- er. ADA CERP is a service of the American Dental Assotiation to assist dental profession- als in identifying quality providers of continue dental education. ADA CERO does not approve or endors individuals courses or instructors, nor does it imply accseptance of credit hoiurs by boards of dentistry. 6 MEDIA CME DENTAL TRIBUNE Middle East & Africa Edition | Jan-Feb 2013

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