Neutral zone recording in computer-guided implant prosthesis: A new digital neuromuscular approach.

Background: Neutral zone (NZ) is a specific area in the oral cavity where muscular opposite forces are null. NZ represents the ideal zone for prosthesis placement. In this study, we compared digital implant planning using conventional technique and using NZ registration through piezography. Methods: Sixty-tree implants were digitally planned. Angular deviation differences between traditional planned and NZ-planned implants were calculated. In addition, interferences with soft tissues (i.e., tongue and cheeks) were evaluated. Results: We observed a significant difference between traditional technique and piezographic approach in terms of implants angulation (p = .003), independent of site. A 4.7% of the planned abutments with traditional technique were placed outside the NZ, causing conflict with soft tissues in the digital model. Conclusions: Compared with traditional technique, piezography allows a significantly different exploitation of the nonconflict area, which potentially translates into better management of soft tissues and improved functionality of the implants.

Canal shaping of different single-file systems in curved root canals.

BACKGROUND/PURPOSE: This study compared maintenance of canal anatomy, occurrence of apical transportation, and working time observed after instrumentation with One Shape New Generation rotary system (Micro-Mega), with those observed after instrumentation with Reciproc (VDW) and WaveOne (Dentsply-Maillefer) reciprocating systems. MATERIALS AND METHODS: The mesial canals of 45 mandibular molars (curvature angles between 35° and 45°) were selected. Specimens were randomly divided into three groups, and canal preparations were performed using One Shape, Reciproc, or WaveOne systems (size #25). A digital double radiographic technique was used to determine apical transportation and change in angle of curvature. Also, working time and instrument failures were recorded. Data were statistically analyzed. RESULTS: During preparation, no file fractured. No statistically significant differences were found among groups. No system showed a significantly faster preparation time than others (P > 0.05). All instruments maintained the original canal curvature well and were safe to use. CONCLUSION: Both continuous rotary instrument and reciprocating systems did not have any influence on the presence of apical transportation or caused an alteration in angle of canal curvature.

Adhesive Cementation of Indirect Composite Inlays and Onlays: A Literature Review.

The authors conducted a literature review focused on materials and techniques used in adhesive cementation for indirect composite resin restorations. It was based on English language sources and involved a search of online databases in Medline, EMBASE, Cochrane Library, Web of Science, Google Scholar, and Scopus using related topic keywords in different combinations; it was supplemented by a traditional search of peer-reviewed journals and cross-referenced with the articles accessed. The purpose of most research on adhesive systems has been to learn more about increased bond strength and simplified application methods. Adherent surface treatments before cementation are necessary to obtain high survival and success rates of indirect composite resin. Each step of the clinical and laboratory procedures can have an impact on longevity and the esthetic results of indirect restorations. Cementation seems to be the most critical step, and its long-term success relies on adherence to the clinical protocols. The authors concluded that in terms of survival rate and esthetic long-term outcomes, indirect composite resin techniques have proven to be clinically acceptable. However, the correct management of adhesive cementation protocols requires knowledge of adhesive principles and adherence to the clinical protocol in order to obtain durable bonding between tooth structure and restorative materials.

Planning implants in the esthetic zone using a new implant 3D navigation system.

Guided implant surgery is becoming a clinical reality in the world of implant dentistry. In recent years, a Computer Aided Implantology Academy has even appeared, confirming the importance of this approach. Different navigation systems are available for the planning of surgical and prosthetic reconstructions. These systems make available to the surgeon and the prosthodontist the instruments necessary to plan a case and to work in a team to deliver a fixed restoration at the time of the surgical procedure in a minimally invasive and predictable way. This article evaluates the usefulness of this kind of planning in the esthetic zone, where perfection is mandatory.