International Journal of Esthetic Dentistry (EN), 03/2010

Of all developments in dental technology, fulfilling the esthetic and functional demands of the patient, especially regarding anterior reconstructions, is still a challenge for both dentists and dental technicians. This becomes more difficult for patients with a previous treatment history that is not ideal. This case presentation demonstrates reconstruction of an anterior zirconia resin-bonded fixed dental prosthesis (RBFDP) for the mandible with a combined treatment approach utilizing veneers for harmonized space distribution on the abutment teeth and an implant-supported zirconia fixed dental prosthesis in the anterior segment of the maxilla. Adhesive cementation of the restorations is also presented in a step-by-step approach based on the current state of the art.

Objective: The main objective of this study was to evaluate the clinical effectiveness of platelet-rich fibrin membrane used in combination with a coronally advanced flap (CAF) and to compare it with the use of an enamel matrix derivative (EMD) in combination with a coronally advanced flap in gingival recession treatment. Materials and methods: 20 split-mouth cases of maxillary anterior teeth or bicuspids presenting with Miller Class I or II gingival recession were treated with a CAF combined with a platelet-rich fibrin membrane (PRF group) or with EMD (EMD group) placed under a CAF. The following parameters were measured at baseline and at 12 months post treatment: gingival recession (GR), apicocoronal width of the keratinized tissue (WKT), and probing depth (PD). Results: Complete root coverage in the PRF group was 65% (13 out of 20 recessions) and 60% in the EMD group (12 out of 20 recessions). GR was 4.10 ± 1.05 mm in the PRF group and 3.90 ± 1.00 mm in the EMD group at baseline, and 1.05 ± 0.45 mm in the PRF group and 1.15 ± 0.65 mm in the EMD group at 12 months. The difference observed between the two groups at 12 months was statistically significant. Average root coverage was 70.5% in the EMD group and 72.1% in the PRF group. WKT was 1.30 ± 0.56 mm in the EMD group and 1.45 ± 0.86 mm in the PRF group at baseline, and 1.90 ± 0.81 mm in the EMD group and 1.62 ± 0.28 mm in the PRF group at 12 months. The difference observed between the two groups at 12 months was not statistically significant. Twelve-month changes in PD were not significantly different between the two groups. The pain intensity was statistically different between groups for the first 5 days, favoring the PRF group. Conclusions: The present study did not succeed in demonstrating any clinical advantage of the use of PRF compared to EMD in the coverage of gingival recession with the CAF procedure. The EMD group showed a higher success rate in increasing WKT than did the PRF group.

A prerequisite for immediate implant placement is fully intact osseous and soft tissue, which can only be achieved by a careful and less-traumatic tooth removal that minimizes damage to the soft and hard tissue structures of the extracted tooth socket. Traditional methods of tooth extraction using forceps and elevators often results in some degree of soft and hard tissue damage, which ranges from slight soft tissue laceration to complete loss of the buccal bony plate and interdental bone crest. This paper describes an extraction technique that utilizes a systematic tooth sectioning approach to help minimize soft and hard tissue loss in the extracted tooth socket.

The objective of the study was to evaluate the effect of immediate polishing, after 24 h and after 1 week, on the surface roughness of two micro-hybrid resins (Esthet-X; Opallis) and one nanoparticle resin (Filtek Z350), as well as verifying maintenance of the polish after 1 year, simulated by means of thermal cycling. Forty-three specimens of each material were made and divided into a control group and three experimental groups. The control group specimens received no surface treatment. Group 1 received finishing with an extra-fine diamond drill and posterior polishing with the systems Enhance and PoGo, immediately after polymerization. Group 2 received the same procedures; however, these were carried out after 24 h of storage. Group 3 received the surface treatment after 7 days of storage. After that, the surface roughness was evaluated by a profilometer. After the initial reading, the specimens were submitted to thermal cycling for 10,000 cycles. After thermal cycling, a new roughness reading was taken. The results showed a higher roughness value for the resin Esthet-X, and the resins Opallis and Z350 presented the same roughness values. As regards the time when polishing was performed, specimens polished immediately after polymerization presented higher roughness values in comparison with the other two periods. After thermal cycling, the statistical analysis showed that the Opallis resin polish had been maintained, whereas for the other two resins, there was a significant reduction in surface smoothness. The surface roughness was influenced by the material and also by the period of polishing; the surface roughness of all tested materials were at a clinically acceptable level.

Objectives: the aim of this study was to evaluate the in vitro color stability of bleached teeth by means of a 6-day staining procedure. Materials and methods: 20 caries-free human mandibular incisors were randomly divided into two groups. Test group: a bleaching agent (Zoom 2, Discus Dental) was applied to the labial surfaces following the manufacturer's instructions. Control group: no bleaching treatment. Using a thermo-cycling device, all teeth were alternately immersed in a 0.9% saline solution at 37°C for 1 hour, and in a coffee solution at 55°C for another hour, in order to simulate the natural tooth-staining process. This procedure was repeated 12 times a day for 6 days. Teeth were polished once a day with a rubber cup and polishing paste. CIELAB color variables (L, a, b) were assessed by means of a spectrophotometer (VITA Easyshade®) and a custom alignment device at baseline, after bleaching, and once a day throughout the 6-day staining treatment. The bleaching result and the color stability of bleached and control group teeth were assessed by matched pair t test and MANOVA. Results: the bleaching agent had a significant whitening effect. The staining treatment did not produce any significant color change on bleached teeth, which maintained the same whiteness achieved after the bleaching treatment. The staining treatment did not produce any significant color change on control teeth. The two groups showed significant differences in both whiteness and lightness changes as a result of the polishing treatment. Conclusions: the Zoom 2 whitening agent produced immediate and long-lasting bleaching results, even if the reduction of b value mainly occurred 24 and 48 hours after the bleaching treatment.