Dental Tribune Asia Pacific Edition No. 3, 2018

12 TRENDS & APPLICATIONS Dental Tribune Asia Paciﬁ c Edition | 3/2018 Highly aesthetic interdisciplinary treatment How ﬁ ne-structure feldspathic ceramic can bestow a natural smile By Dr Babak Varzideh & Ludger Schlütter, Germany The smile dwells only on the lips, but laughter has its place and its grace among the teeth, noted the French scholar Joseph Joubert in the nineteenth century. Tooth morphol- ogy, surface texture, the interplay of colour and light, as well as tooth po- sition, all have a decisive effect on laughter. However, for rehabilita- tion of the aesthetic zone, the smile line and the gingival margin must be taken into consideration in the treatment plan in order to make the patient’s smile complete.1 Often, a matter of millimetres determines whether something is perceived as aesthetic or not.2 As a result, meticulous plan- ning and consistent and active in- volvement of the patient are even more important in developing the ﬁ nal treatment result.3 This is the only way for the ﬁ nal restoration central incisors appeared to have shifted in the vestibular direction and had left the dental arch. The vi- tality test was positive. Massive di- astemata could be seen between teeth #11 and 21, as well as between teeth #21 and 22. On the mesial sur- face of tooth #12, an attempt had been made to cosmetically com- pensate for the tooth gap with composite. A palatal splinting of teeth #11 and 21 with a retainer wire was visible through the gap. A re- cession at tooth #11 interrupted the harmonious course of the gingival margin. In the vestibular area, gen- eralised decalciﬁ cation could be seen, indicating ﬁ xed orthodontic treatment. Functional disorders were not diagnosed. Habitual inter- cuspation and central condylar po- sition did not show any deviation. Moderate bone loss could be seen at teeth #11 and 21 in radiographs. this purpose, the result. For self-hardening composite material Structur 3 (VOCO) was applied to the silicone key and it was reposi- tioned in the patient’s mouth. This produced a long-term temporary that was similar to the wax-up. The patient was now able to obtain a ﬁ rst impression of the appearance of the ﬁ nal restoration. Highly aesthetic material selection The decision was made for a splinted restoration of teeth #11 and 21 to relieve the teeth function- ally and to ensure a long-term ﬁ xa- tion of the orthodontic result at the same time. In order to produce highly aesthetic work, the dentist and dental technician decided on a zirconium dioxide framework 1 Fig. 1: Initial situation with PFM crowns and diastemata. lope technique).7 For optimal heal- ing, the ﬁ xation was performed with microsurgical single-button sutures. The consistent proximal splinting of the temporary on the incisors also allowed a tension- free, coronal ﬁ xation of the gingi- val area through double-crossed sutures (Fig. 3).8 After the gingival architecture had stabilised as de- portion of 1M1 in the mixing ratio in order to achieve a fresher effect and to compensate for the opaquer zirconium dioxide framework. Preparation in enamel Owing to the initial caries, a classic veneer preparation was car- ried out on teeth #12 and 22. In do- 2 3 4 Fig. 2: Idealised wax-up with labial trimming.—Fig. 3: State after microsurgical gingiva correction at tooth #11.—Fig. 4: Precise shade-taking procedure with the VITA Toothguide 3D-MASTER. to be harmoniously integrated into the overall appearance and in- visibly attractive to the observer. In the following case, this could only be achieved by an interdisci- plinary orthodontic, microsurgi- cal and restorative procedure.4 The young woman had already visited numerous dental practices and several dentists had even warned her that little could be done. Her expectations and psy- chological strain were correspond- ingly high. Case description A 28-year-old female patient presented to the dental practice stating that she was dissatisﬁ ed with the aesthetics of her maxil- lary anterior. At the age of 8, she had had a bicycle accident that led to a crown fracture without pulp involvement of teeth #11 and 21. Up to this point, the accident had signiﬁ cantly affected the patient’s appearance. Up to her 20th birth- day, dentists had tried to stabilise the situation with composite. In the end, teeth #11 and 21 were re- stored with porcelain-fused-to- metal (PFM) crowns (Fig. 1). At ﬁ rst glance, the crowns seemed dull, without any interplay of light, and showed exposed me- tallic crown margins. Furthermore, the restorations were oversized in the incisal area and did not match the remaining teeth or the face of the young woman. In general, the Orthodontics and wax-up After eight months of ortho- dontic treatment using a multi- band appliance, teeth #11 and 21 were harmoniously integrated into the dental arch. During the course of the therapy, it was possible to re- duce the diastemata and level the asymmetrical tooth position for the subsequent restoration. A model of the maxilla was created using an anatomical impression and could be idealised with a wax-up on the maxillary incisors (Fig. 2).5 The course of the gingival margin was subtractively cor- rected through labial trimming. A key was made of this target state with kneading silicone. The PFM crowns were slit and removed at the next session. The stumps were prepared again, and the incisors were then restored with a splinted temporary to ﬁ x the orthodontic made of pre-coloured VITA YZ TCo- lor LL1/light (VITA Zahnfabrik). The high-strength material ensures a high stability, and its opacity relia- bly covers discoloured dentine ar- eas. The framework was to be ve- neered with the ﬁ ne-structure feldspathic ceramic VITA VM 9 (VITA Zahnfabrik) to ensure a natu- ral and youthful interplay of col- our and light of the restoration. Similar to this and in the same op- eration, extremely thin veneers were to be layered on teeth #12 and 22, also with VITA VM 9, to guaran- tee the structural harmony of the four adjacent layers.6 Plastic microsurgery Even after the orthodontic treatment and the idealising tem- porary restoration, gingival ﬂ aws could still be seen at tooth #11. To- gether with the patient, the deci- sion was made for a microsurgical correction of this vestibular reces- sion. In the course of the gingival management, a free mucosal graft was harvested from the palate. Af- ter the minimally invasive sulcu- lar preparation of a mucosal pocket at tooth #11 vestibularly, the autologous connective tissue was plastically positioned (enve- sired, tooth shade determination and preparation followed. Three-dimensional colour space Toothguide In order to prevent the teeth from drying out and thereby to avoid determining a basic tooth shade that was too light, the tooth shade was determined with the 3D-MASTER VITA (VITA Zahnfabrik) before the preparation (Fig. 4).9 This method allows an absolutely precise tooth shade determination in three quick and systematic steps, since the complete 3-D tooth shade space can be reproduced here. In the ﬁ rst step, the basic value is determined. Then, the correct chroma is selected and the hue is matched. This shade-taking proce- dure with a larger shade spectrum has especially proven its worth in the highly aesthetic area. In this case, the tooth shade determina- tion was oriented to the opposing dentition and the remaining teeth #12 and 22. A mixture of 1M2 (80 %) and 1M1 (20 %) was determined for the veneering on teeth #12 and 22 (Fig. 5). For teeth #11 and 21, the de- cision was made for a larger pro- 5 Fig. 5: Diagram of the tooth shade-tak- ing procedure. ing so, careful attention was paid to the retention in enamel and to the removal of demineralised areas in order to ensure optimised adhesive bonding during the course of treat- ment.10 Teeth #11 and 21 were cleaned just before impression tak- ing. The minimally invasive prepa- ration on teeth #12 and 22 was per- formed with a ﬁ ne-grain torpedo- shaped bur and a ﬂ ame-shaped bur. The iso-gingival preparation margin showed a considerable chamfer and stretched from the vestibular area into the interdental areas, then tapered out straight in the palatal direction. The incisal area was only slightly rounded off. The impression was taken with Aq-

Dental Tribune Asia Pacific Edition No. 3, 2018

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