Regeneration of Intrabony Defects Using a Novel Magnesium Membrane.

Background and Objectives: Due to their specific morphology, the regeneration of intrabony defects (IBDs) represents one of the greatest challenges for clinicians. Based on the specific properties of a magnesium membrane, a new approach for the surgical treatment of IBD was developed. The surgical procedure was described using a series of three cases. Materials and Methods: The patients were healthy individuals suffering from a severe form of periodontitis associated with IBD. Based on radiographic examination, the patients had interproximal bone loss of at least 4 mm. Due to its good mechanical properties, it was easy to cut and shape the magnesium membrane into three different shapes to treat the specific morphology of each IBD. In accordance with the principles of guided bone regeneration, a bovine xenograft was used to fill the IBD in all cases. Results: After a healing period of 4 to 6 months, successful bone regeneration was confirmed using radiological analysis. The periodontal probing depth (PPD) after healing showed a reduction of 1.66 ± 0.29 mm. Conclusions: Overall, the use of the different shapes of the magnesium membrane in the treatment of IBD resulted in a satisfactory functional and esthetic outcome.

Different Conical Angle Connection of Implant and Abutment Behavior: A Static and Dynamic Load Test and Finite Element Analysis Study.

Dental implants are artificial dental roots anchoring prosthetic restorations to replace natural teeth. Dental implant systems may have different tapered conical connections. Our research focused on the mechanical examination of implant-superstructure connections. Thirty-five samples with 5 different cone angles (24°, 35°, 55°, 75°, and 90°) were tested for static and dynamic loads, carried out by a mechanical fatigue testing machine. Fixing screws were fixed with a torque of 35 Ncm before measurements. For static loading, samples were loaded with a force of 500 N in 20 s. For dynamic loading, the samples were loaded for 15,000 cycles with a force of 250 ± 150 N. In both cases, the compression resulting from load and reverse torque was examined. At the highest compression load of the static tests, a significant difference (p = 0.021) was found for each cone angle group. Following dynamic loading, significant differences (p < 0.001) for the reverse torques of the fixing screw were also shown. Static and dynamic results showed a similar trend: under the same loading conditions, changing the cone angle-which determines the relationship between the implant and the abutment-had led to significant differences in the loosening of the fixing screw. In conclusion, the greater the angle of the implant-superstructure connection, the smaller the screw loosening due to loading, which may have considerable effects on the long-term, safe operation of the dental prosthesis.

Bioactive coatings for dental implants: A review of alternative strategies to prevent peri-implantitis induced by anaerobic bacteria.

Members of oral bacterial communities form biofilms not only on tooth surfaces but also on the surface of dental implants that replace natural teeth. Prolonged interaction of host cells with biofilm-forming anaerobes frequently elicits peri-implantitis, a destructive inflammatory disease accompanied by alveolar bone loss leading to implant failure. Here we wish to overview how the deposition of bioactive peptides to dental implant surfaces could potentially inhibit bacterial colonization and the development of peri-implantisis. One preventive strategy is based on natural antimicrobial peptides (AMPs) immobilized on titanium surfaces. AMPs are capable to destroy both Gram positive and Gram negative bacteria directly. An alternative strategy aims at coating implant surfaces - especially the transmucosal part - with peptides facilitating the attachment of gingival epithelial cells and connective tissue cells. These cells produce AMPs and may form a soft tissue seal that prevents oral bacteria from accessing the apical part of the osseointegrated implant. Because a wide variety of titanium-bound peptides were studied in vitro, we wish to concentrate on bioactive peptides of human origin and some of their derivatives. Furthermore, special attention will be given to peptides effective under in vivo test conditions.