This study introduces the effect of the thickness of a bacterial cellulose membrane by comparing the bone regeneration effect on rat skulls when using a collagen membrane and different thicknesses of resorbable bacterial cellulose membranes for guided bone regeneration. Barrier membranes of 0.10 mm, 0.15 mm, and 0.20 mm in thickness were made using bacterial cellulose produced as microbial fermentation metabolites. Mechanical strength was investigated, and new bone formation was evaluated through animal experimental studies. Experimental animals were sacrificed after having 2 weeks and 8 weeks of recovery, and specimens were processed for histologic and histomorphometric analyses measuring the area of bone regeneration (%) using an image analysis program. In 2 weeks, bone-like materials and fibrous connective tissues were observed in histologic analysis. In 8 weeks, all experimental groups showed the arrangement of osteoblasts surrounding the supporting body on the margin and center of the bone defect region. However, the amount of new bone formation was significantly higher (p < 0.05) in bacterial cellulose membrane with 0.10 mm in thickness compared to the other experimental groups. Within the limitations of this study, a bacterial cellulose membrane with 0.10 mm thickness induced the most effective bone regeneration.

The purpose of this study was to evaluate the bone-generating ability of a new bovine-derived xenograft (S1-XB) containing hydrogel. For control purposes, we used Bio-Oss and Bone-XB bovine-derived xenografts. S1-XB was produced by mixing Bone-XB and hydrogel. Cell proliferation and differentiation studies were performed to assess cytotoxicities and cell responses. For in vivo study, 8 mm-sized cranial defects were formed in 16 rats, and then the bone substitutes were transplanted into defect sites in the four study groups, that is, a Bio-Oss group, a Bone-XB group, an S1-XB group, and a control (all n = 4); in the control group defects were left empty. Eight weeks after surgery, new bone formation areas were measured histomorphometrically. In the cell study, extracts of Bio-Oss, Bone-XB, and S1-XB showed good results in terms of the osteogenic differentiation of human mesenchymal stem cells (hMSCs) and no cytotoxic reaction was evident. No significant difference was observed between mean new bone areas in the Bio-Oss (36.93 ± 4.27%), Bone-XB (35.07 ± 3.23%), and S1-XB (30.80 ± 6.41%) groups, but new bone area was significantly smaller in the control group (18.73 ± 5.59%) (p < 0.05). Bovine-derived bone graft material containing hydrogel (S1-XB) had a better cellular response and an osteogenic effect similar to Bio-Oss.

This in vitro study compared the cutting efficiency of natural diamond burs (NDB) and synthetic diamond burs (SDB) on zirconia and natural teeth. Two types of diamond rotary instruments with identical specifications (TR-13, Tapered Round End) were evaluated using 100 zirconia specimens and 100 extracted molars. Each bur was tested through 10 consecutive cutting cycles under standardized conditions (200,000 rpm, 2 N force, water coolant). Cutting efficiency was evaluated based on weight loss per unit time (mg/min). Surface characterization was performed using field-emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDS). For zirconia cutting, NDB demonstrated significantly higher cutting efficiency than SDB at all cycles (p < 0.05), with 38.9% greater total material removal (115.97 ± 2.22 mg versus 83.46 ± 2.08 mg). NDB also exhibited lower wear rates (40.00% versus 49.68% reduction). For natural tooth cutting, no significant differences were observed between NDB and SDB (p > 0.05). EDS analysis showed that SDB exhibited greater carbon loss (13.46% versus 2.49%) and increased surface heterogeneity after repeated use. These findings indicate that natural diamond burs are superior for cutting high-hardness materials such as zirconia, while both bur types perform equivalently on natural teeth.

Background/Objectives: This study aimed to compare the final impressions obtained using three different impression techniques in completely edentulous patients, focusing on the clinical applicability of the JB Tray^® for immediate custom tray fabrication with a polycaprolactone-based thermoplastic resin. Methods: Five edentulous patients were recruited for a preliminary clinical evaluation, and three impression techniques were tested: (1) JB Tray^® (JB), which allows simultaneous border molding and final impression taking; (2) the conventional modeling compound border-molded technique (MC, control); and (3) the one-step silicone border-molded technique (OS). All impressions were made by a single prosthodontist, and the internal surfaces were digitized using a 3D scanner for analysis of internal fit. Each arch was divided into reference regions for quantitative comparison. Statistical significance was set at p < 0.05. Results: Color map analysis (threshold of ±1.0 mm) revealed that the JB Tray^® group exhibited wider border extension in both the maxilla and mandible compared with the modeling compound and silicone groups, with a more pronounced effect in the mandible. However, no statistically significant differences in overall internal fit were observed among the three methods (p > 0.05). Conclusions: These preliminary results due to small sample size suggest that the JB Tray^® enables efficient impression taking in edentulous patients and can serve as a viable alternative to conventional custom tray techniques. Further research with a larger sample size is warranted to support widespread clinical application.