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Objective Laser profiling of titanium has been of considerable interest in the field of oral implantology. However, very few pre-clinical and clinical studies have been performed with laser-treated implants, especially focusing on isotropic roughness topography. The aim of the study was to compare the cortical bone response of Ti-implants discs treated with pico-sec pulsed laser ( LAS) and conventional grit-blasted/acid-etched ( GAE) method. Materials and methods Prior to the in vivo experiment, in vitro cell viability testing of the LAS surface treatment was preformed. Then, 5 mm diameter Titanium (Ti) discs treated with LAS and GAE method were implanted in a pre-validated rabbit tibia cortical bone model and assessed with histology and histomorphometric measurements. In total, eight New Zealand White adult female rabbits were used. Results The in vitro cell viability testing with osteoblast-like cells confirmed cytocompatibility of the LAS surface treatment. Further, the rabbit experiment demonstrated a bone-to-implant contact of 68% (±17) for the laser-treated discs and 49% (±21) for the GAE discs 8 weeks after the implantation, which was statistically not different. Conclusion Laser surface treatment gives the same results to the grit-blasting/acid-etched method and thus is a valid alternative to conventional roughening for dental implant materials. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to investigate the influence of different implant placement techniques on the early bone healing response in an animal model. In the present study, 24 cylindrical-screw-type implants with a diameter of 4.2 mm (Dyna) were installed, using three different surgical techniques; (1) 5% undersized, using a final drill diameter of 4 mm; (2) 15% undersized, using a final drill diameter of 3.6 mm; and (3) 25% undersized, using a final drill diameter of 3.2 mm. After 3 weeks of implantation period, the peri-implant bone response was histologically evaluated and the percentage of bone-implant contact (%BIC) calculated. New bone formation was more pronounced for implants placed with the 5% undersized or 15% undersized technique, as compared with implants installed with the 25% undersized technique. Histomorphometrical data corroborates these findings as the %BIC was significantly higher for implants inserted with the 5% undersized (47.7 ± 11.1) or 15% undersized protocol (47.5 ± 9.5) as compared with implants inserted with the 25% undersized technique (32.1 ± 9.7). No significant difference in %BIC could be observed between the 5% undersized and 15% undersized installed implants. Within the limitation of the present study, it was concluded that excessive compression of the host bone, when a discrepancy between implant and final drill diameter more than 15%, can result in an inferior tissue response in the early stage of healing. To compare research results in the future, it is advised to specify the term 'undersized' by mentioning the real reduction in diameter. Tabassum A, Meijer GJ, Walboomers XF, Jansen JA, Biological limits of the undersized surgical technique: a study in goats. Clin. Oral Impl. Res. , 2011; 129-134. doi: 10.1111/j.1600-0501.2010.02016.x [ABSTRACT FROM AUTHOR]

Objectives: Histological sections of preclinical animal studies have shown that new bone formation around dental implants frequently contains debris derived from the original bone. Whether such debris by itself is osteogenic, i.e., can influence the process of new bone formation after implant placement, is still unknown. We therefore aim to investigate if such debris does have osteogenic potential. Material and methods: To substantiate our hypothesis, we performed an in vitro study in which titanium screws were placed into animal bone, and immediately removed. Without additional treatment these were placed into a cell culture medium provided with β-glycerophosphate. We used Von Kossa staining and scanning electron microscopy to examine calcifications on the surface of the implants. Additionally, total DNA analysis, alkaline phosphates activity, and calcium content were assessed on the screw surface. Results: Light and electron microscopy revealed the increasing presence of calcified matter on the implant surface. DNA amounts doubled from days 1 to 6, while alkaline phosphatase activity and calcium content showed a pronounced increase over the entire incubation time. None of these phenomena occurred on the control samples in the same medium. Conclusions: From these results, we proved that bone debris, which arises from dental implant placement, and which is moved along by the inherent roughness of the implant, by itself has osteogenic potential. [ABSTRACT FROM AUTHOR]

Objectives: Electrostatic spray deposition (ESD) is a new technique to deposit calcium phosphate (CaP) coatings. The aim of the present study was to evaluate the bone behavior of ESD CaP-coated implants with various degrees of crystallinities in the trabecular bone of the femoral condyle of goats. Material and methods: Using the ESD technique, thin porous CaP coatings were deposited on tapered, conical, screw-shaped titanium implants. Three different heat-treatments were applied, resulting in amorphous CaP (400°C, ESD1), crystalline carbonate apatite (500°C, ESD2), and crystalline carbonated hydroxyapatite (700°C, ESD3). Implants were inserted into the trabecular bone of the femoral condyles of goats for 12 weeks, and titanium (Ti) implants served as controls. Results: The results showed that ESD-derived coatings are osteocompatible. Histomorphometrical analysis showed that the application of a CaP coating resulted in more bone contact along the press-fit area of the implant compared with the Ti implants. Moreover, the percentage bone contact of the ESD3-coated implants was increased, compared with the Ti control group. Regarding the other coatings, no differences were found compared with the control group. Conclusion: Crystalline carbonated hydroxyapatite ESD-coated implants positively influenced the biological performance compared with Ti control implants. [ABSTRACT FROM AUTHOR]