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Aim: The surface roughness of 3 different resin restorative materials polymerized with a halogen and a plasma arc curing light, following finishing and polishing was evaluated in vitro., Methods: Using a metal mold, 10 block specimens were prepared from each material. A Mylar strip was placed on both sides of the mold. Five specimens from each material were cured with the halogen lamp, while the other 5 were polymerized with the plasma arc lamp. In both groups the surface exposed to curing light was finished and polished with the Enhance system (Dentsply). The opposite surface was not treated and served as a control. Both surfaces of each specimen were analyzed with a laser profilometer: the roughness average (R(a)) was evaluated. The Vickers microhardness of the polished surfaces was also calculated. All data were statistically analyzed with the Mann-Whitney test. A regression test was carried out to evaluate the possible correlation between roughness and microhardness., Results: The smoothest surfaces were obtained when composites were cured against a Mylar strip. Roughness was significantly increased in both groups in the treated surfaces. A significant correlation between roughness and microhardness could not be demonstrated., Conclusions: This study demonstrated that the surface polymerized against a Mylar strip was the smoothest surface produced, while the roughness of the Mylar-formed surface was significantly increased by finishing and polishing. Surface roughness following polishing is material-dependent.

Aim: The aim of the study was to evaluate the reaction exothermia of 2 relining resins for temporary crowns. The resins used were Duralay, a methacrylate-based resin, and Protemp II, a bisacrylic resin., Methods: The coronal parts of an adult molar and of an impacted one were used. Abutments were obtained from the crowns, while the radicular part was sectioned in order to insert a thermocouple into the pulpal chamber. During the experiment the tooth with the polymerising resin was put into an oral cavity simulator to keep a constant temperature. The thermal increase during polymerisation of the 2 resins was recorded for 6 minutes at 5 seconds intervals and with 1 and 2.5 mm dentin thickness (n = 10). Data were statistically analysed by variance analysis with Scheffe test., Results: The intrapulpal thermal increase was significantly higher in relation to the type of resin (Duralay p < 0.0001), thickness (1 mm p < 0.0001) and type of dentin (young dentin p < 00001)., Conclusions: In order to protect the pulp, during the direct relining of a temporary crown, it is recommendable to choose the best combination among resin, type of dentin and its residual thickness, besides adequate cooling techniques.

Aim: The aim of this study was to evaluate the influence of fiber post on all-ceramic prosthetic restorations, using the spectrophotometer Miniscan XE. Data were recorded according to the CIEL*a*b* system and the color difference (DE) was calculated., Methods: Carbon fiber Composipost (RTD) and quartz fiber Lightpost (RTD) posts were used. Square specimens (12x12 mm) were prepared using 9 #1 posts, covered with Z100 (3M) composite layers of different thickness (2, 3 and 4 mm) and color A3; 12x12 mm ceramic specimens (Finesse All Ceramic - 3M) of 2 and 3 mm thickness and color A3, were prepared using both opaque dentin and not., Results: With 2 and 3 mm thick ceramic layers, there was no color difference between carbon fiber specimens and quartz fiber specimens. Using the opaque dentin did not determine difference between groups., Conclusion: In this study, according to results, a 3 mm thick ceramic layer always produced a DE<1, independently from the endodontic post. However, 2 mm thick ceramic layers were able to cover every kind of endodontic posts, even if with a DE=+/-1.6, and therefore are clinically acceptable.

Medium-term results in the treatment of acetabular bone loss using bulk and/or morselized bone allografts supported by acetabular reinforcement rings are reported. A total of 164 hips in 157 patients were treated by means of this reconstruction technique. The devices employed were Müller ARRR in 24 cases and Burch-Schneider APC in 140. Mean follow-up was 67 months (minimum 12, maximum 123). A total of 4 patients developed deep infection that was treated by resection-arthroplasty. Aseptic loosening of acetabular implant following extensive resorption of bone graft was observed in 5 cases: 3 of the cases underwent acetabular revision. Clinical results were evaluated based on the Harris Hip Score: mean values of 35 and 78 were assessed preoperatively and at follow-up, respectively. X-ray signs of incorporation of bone graft were observed in all cases that progressed successfully.