Third molar transplantation combined with an osteotome sinus lift - two case reports.

We report here on our application of the socket lift technique to create a transplant socket for the transplanted maxillary molar. These outcomes suggest that this technique is likely to be effective for tooth transplantation when the maxillary sinus bottom is close to the alveolar crest.

Accelerated Osteogenic Differentiation and Bone Formation on Zirconia with Surface Grooves Created with Fiber Laser Irradiation.

BACKGROUND: Modification of the surface topography of biomaterials is a critical factor for the proliferation and differentiation of osteoblasts. Elucidating the biological response to surface roughening is necessary for clinical application of zirconia implants. PURPOSE: To investigate the effects of fiber laser-induced zirconia surface roughening on cultured osteoblast-like cell morphology, proliferation, differentiation, and calcification, and on in vivo bone formation. MATERIALS AND METHODS: Sixty-six machine-surfaced yttria-tetragonal zirconia polycrystal plates (S-Zr) and 16 machine-surfaced implants were used as controls. We prepared 66 rough plates (R-Zr) and 16 rough implants by surface treatment using a fiber laser. RESULTS: MC3T3-E1 cells spread well in all directions on S-Zr, whereas elongated cells with poorly organized actin stress fibers were observed on R-Zr. Cell proliferation was significantly greater on R-Zr than on S-Zr. The Runx2 mRNA level increased time dependently in osteogenic culture condition. Alkaline phosphatase activity and osteocalcin mRNA levels were higher on R-Zr compared with S-Zr. Alizarin red S staining revealed greater calcification on R-Zr than on S-Zr. Laser treatment of zirconia implant bodies placed in rat tibiae increased the bone-implant contact ratio and removal torque considerably. CONCLUSIONS: Our results suggest that fiber laser irradiation produces adequate surface roughening of zirconia ceramics to support osseointegration.

Human mandibular trabecular bone density correlation with mechanical strength: implications for implant dentistry.

PURPOSE: The prognosis of a dental implant depends on the mechanical properties of the bone. The preoperative diagnosis of bone quality has become more important, because the immediate loading procedure is now widely used, and a firm initial stability is required. Quantitative computed tomography (QCT) is an effective method of determining selectively the bone mineral density (BMD) of the trabecular bone mostly responsible for the survival of the implant. In this project, we investigated the relationship between the BMD measured by QCT and the mechanical strength of the mandible. MATERIALS AND METHODS: The BMD (mg/mL) of 58 trabecular bone specimens from 6 embalmed human cadaver mandibles were obtained using QCT. The compressive strength to break point was performed with a mechanical device. Each specimen was washed and weighed. RESULTS: The mean values of BMD for the anterior, premolar, and molar region were 633.3, 571.0, and 518.3 mg/mL, respectively. The mean values of compressive strength were 0.237, 0.216, and 0.196 kN, and the ash weights were 0.047, 0.044, and 0.039 g, respectively. There was a positive correlation between the BMD and the mechanical strength (R = 0.77) and between the ash weight and the mechanical strength (R = 0.84). CONCLUSION: There was strong correlation of bone strength, bone mineral, and bone density by QCT. QCT is an excellent preoperative diagnostic tool to select the most mechanically appropriate implant for initial stability and improve the survival prognosis.

Students' opinion of a predoctoral implant training program.

Implant treatment today is highly predictable and provides valid restorative options for the completely or partially edentulous patient. In Japan, many dental care facilities have incorporated implant treatment, and such treatment is no longer rare. For predoctoral students, the educational environment related to implants is not always applicable in present clinical settings. In this article, we describe the implant training program developed at our university for predoctoral education, and we report the changes in student opinions regarding implant treatment by comparing pre- and post-training opinions. The newly developed models for implant training were effective in increasing student understanding that implant treatment is one prosthetic option for restoring missing teeth. In a survey of predoctoral students, responses indicating negative opinions toward implant treatment decreased after training, and responses indicating positive opinions increased. These findings indicated that this training was effective in deepening student understanding of implant treatment.