Allogen bones from tissue bank are often used in dentistry although the data analyzing the long-term success in mandible are scarce. This study evaluated by computed tomography scans (CTS) the bone resorption around the implants installed on fresh frozen bone (FFB) previously grafted, after 4 years of occlusal rehabilitation. Six subjects were grafted with blocks in posterior mandible using FFB. After 6 months, 27 implants were placed and after further 4 months the prostheses were delivered. Following 4 years of the final rehabilitation procedures, another CTS was done in order to measure the resorption in periimplant bone crest at the proximal implant surfaces. It was observed a 100 % survival rate of the implants after 4 years of the fixture installation. The marginal bone resorption after 48 months was 2.82 ± 1.63 mm and no statistical significant difference was observed along the region where the implants were fixed when compared with the interimplantar space. In addition there was no significant correlation regarding the length of the implant used and the amount of marginal bone resorption. The conclusion is that grafted areas with FFB are suitable to implant installation in the posterior mandible.

Bone resorption of the posterior mandible can result in diminished bone edge and, therefore, the installation of implants in these regions becomes a challenge, especially in the presence of the mandibular canal and its contents, the inferior alveolar nerve. Several treatment alternatives are suggested: the use of short implants, guided bone regeneration, appositional bone grafting, distraction osteogenesis, inclined implants tangential to the mandibular canal, and the lateralization of the inferior alveolar nerve. The aim was to elucidate the success rate of implants in the lateralization technique and in inferior alveolar nerve transposition and to determine the most effective sensory test. We conclude that the success rate is linked to the possibility of installing implants with long bicortical anchor which favors primary stability and biomechanics.

The aim of this study was to evaluate the stress distribution of different retention systems (screwed, cemented, and mixed) in 5-unit implant-supported fixed partial dentures through the photoelasticity method. Twenty standardized titanium suprastructures were manufactured, of which 5 were screw retained, 5 were cement retained, and 10 were mixed (with an alternating sequence of abutments), each supported by 5 external hexagon (4.0 mm × 11.5 mm) implants. A circular polariscope was used, and an axial compressive load of 100 N was applied on a universal testing machine. The results were photographed and qualitatively analyzed. We observed the formation of isochromatic fringes as a result of the stresses generated around the implant after installation of the different suprastructures and after the application of a compressive axial load of 100 N. We conclude that a lack of passive adaptation was observed in all suprastructures with the formation of low-magnitude stress in some implants. When cemented and mixed suprastructures were subjected to a compressive load, they displayed lower levels of stress distribution and lower intensity fringes compared to the screwed prosthesis.

Introduction: Disc displacement without reduction with limited opening is an intracapsular biomechanical disorder involving the condyle-disc complex. With the mouth closed, the disc is in an anterior position in relation to the condylar head and does not reduce with mouth opening. This disorder is associated with persistent limited mandibular opening. Case report: The patient presented severe limitation to fully open the mouth, interfering in her ability to eat. Clinical examination also revealed maximum assisted jaw opening (passive stretch) with less than 40 mm of maximum interincisal opening. Magnetic resonance imaging was the method of choice to identify the temporomandibular disorders. Conclusion: By means of reporting this rare case of anterior disc displacement without reduction with limited opening, after traumatic extraction of a mandibular third molar, in which manual reduction of temporomandibular joint articular disc was performed, it was possible to prove that this technique is effective in the prompt restoration of mandibular movements.

It was evident that the silicone membrane reduced, but did not prevent, penetration of these species into external-hex implants.