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PURPOSE To analyze peri-implant bone loss around six different types of implant-prosthetic connections over a 2-year follow-up period. MATERIALS AND METHODS A total of 120 implants were divided into six groups (n = 20), three with crestally and three with supracrestally placed implants, with different internal connections, placed in posterior sectors (molar and premolar), and bearing one-piece CAD/CAM restorations screwed directly to each implant's prosthetic platform. Bone height was measured from parallelized periapical radiographs taken at the moment of loading and 2 years later. RESULTS The patient sample included 61 subjects, 36 men and 25 women. Significant differences were found in bone loss between groups, the implant with internal hex and convergent transmucosal collar showing the least bone loss (P < .001) in comparison with the other designs. Supracrestally placed implants underwent less bone loss than crestally placed implants (P = .025). CONCLUSION Peri-implant bone loss is influenced by the level of implant placement in relation to the bone crest (crestal or supracrestal) and by the morphology of the prosthetic platform.

Epidermolysis bullosa belongs to a group of genetic diseases that present with skin disorders and is characterized by generalized blister formation in response to mechanical trauma. This article reports on the management of a recessive dystrophic epidermolytic patient with four remaining periodontally compromised maxillary teeth. Treatment involved placement of four maxillary implants and use of computer-aided design/computer-assisted manufacture techniques to fabricate a fixed full-arch implant-supported prosthesis. The prescribed dental treatment protocol led to a successful short-term prosthodontic outcome.

PURPOSE To compare the effectiveness of different methods of fractured screw fragment retrieval from dental implants, comparing a conventional method (use of an exploration probe and ultrasonic tips) with two mechanical retrieval kits. MATERIALS AND METHODS One hundred thirty-five screws in implant internal connections were fractured to test fragment retrieval comparing three methods: conventional method with the use of an explorer probe and ultrasonic tips (group CE), extraction with a mechanical kit with a guide cylinder (group MK1), and extraction with a mechanical kit without a guide cylinder (group MK2). Extraction success and retrieval times for each method, as well as success and retrieval times in relation to fracture depth-coronal, middle, or apical-were analyzed by means of chi-square, Fisher exact, Kruskal-Wallis, and Mann-Whitney tests (P < .05). The integrity of implant internal threads was also analyzed. RESULTS The extraction success rates for groups MK2, CE, and MK1 were 93.3%, 73.3%, and 20%, respectively. The mean ± SD extraction times were 2 minutes, 56 seconds ± 2 minutes, 9 seconds; 3 minutes, 15 seconds ± 1 minute, 48 seconds; and 13 minutes, 34 seconds ± 7 minutes, 25 seconds for groups MK2, CE, and MK1, respectively. Statistically significant differences were found in the number of fractured screws extracted and in the retrieval time. No significant differences were found for retrieval time or extraction success in relation to the depth of the fracture. CONCLUSION The mechanical kit without the guide cylinder achieved the best results with respect to the number of screw fragments retrieved, retrieval time, and preservation of implant internal threads.

Dental implants are one of the most widely used treatments for the rehabilitation of partially or completely edentulous areas. Achieving proper passive adjustment of the implant-supported prosthesis improves its long-term prognosis. This article discusses a new technique for digitally printing prostheses supported by multiple implants with optimum passive fit. The technique is based on a stereophotogrammetry system that captures the exact location of prosthetic implant platforms. This photogrammetry device takes 10 pictures per second with an error margin of less than 10 μm between two scanbodies and identifies the spatial position of each implant without physical contact. Three-dimensional data for each implant are registered in vector format, together with interrelated implant angles and distances. The information is then stored in an STL file.