The purpose of this study was to evaluate the effect of posterior occlusal support of natural teeth and artificial teeth on oral functions and standing motion. Patients who had been treated with removable prostheses were enrolled as the subjects. Their systemic conditions (body mass index (BMI) and skeletal muscle mass index (SMI)) were recorded. The subjects were classified into two groups according to a modified Eichner index: B1–3 (with posterior occlusal support) and B4C (without posterior occlusal support). Maximum occlusal force (MOF), masticatory performance (MP), and standing motion (sway and strength) were evaluated for cases with and without removable prostheses. There were no significant differences in BMI and SMI between the B1–3 group and the B4C group. The subjects with removable prostheses demonstrated significantly higher values in MOF, MP, and sway and strength than the subjects without removable prostheses. The comparison of oral functions between the B1–3 group and the B4C group revealed that the positive effect of posterior occlusal support of natural teeth and removable prostheses and the significant positive effects of posterior occlusal support on standing motion were partly observed in these comparisons. Posterior occlusal support of natural teeth and even of removable prostheses may contribute to the enhancement of oral functions and standing motion.

Background: A novel type of implant (Straumann® BLX implant) has been developed for certain stability from the mechanical and biological aspects and is expected for the implant placement in atrophic maxilla with sinus floor elevation (SFE). Purpose: The aim of this study was to evaluate the primary stability in the implants with different macrodesigns in an SFE simulated model. Primary stabilities defined as maximum insertion torque (MIT) and implant stability quotient (ISQ) were compared between this novel type of implant and other types. Materials and Methods: Five types of Straumann® 10 mm length implants (Standard Plus; SP, Tapered Effect; TE, Bone Level; BL, Bone Level Tapered; BLT and BLX) and two types of Straumann® 6 mm length implants (SP short, BLX short) were used in this study. Each implant was inserted through 5 mm–thick porcine iliac crest blocks (an SFE simulated model). Primary stability was evaluated by using MIT and ISQ. Results: The mean value of MIT for BLX group showed significantly higher values than SP, BL (p < 0.01), and TE (p < 0.05) groups. The mean value of ISQ for BLX group was significantly higher than the other groups (p < 0.01). The mean value of MIT and ISQ for BLX and BLX short group were significantly higher than those for SP and SP short group (p < 0.01). Conclusions: In an SFE simulated ex vivo model, BLX group showed the highest values. These results suggest that implant selection can play a crucial role in the achievement of primary stability during SFE and simultaneous implant placement.

Medication-related osteonecrosis of the jaw (MRONJ) is an intractable disease that is typically observed in patients with osteoporosis or tumors that have been treated with either bisphosphonate (BP) or antiangiogenic medicine. The mechanism of MRONJ pathogenesis remains unclear, and no effective definitive treatment modalities have been reported to date. Previous reports have indicated that a single injection of benidipine, an antihypertensive calcium channel blocker, in the vicinity of a tooth extraction socket promotes wound healing in healthy rats. The present study was conducted to elucidate the possibility of using benidipine to promote the healing of MRONJ-like lesions. In this study, benidipine was administered near the site of MRONJ symptom onset in a model rat, which was then sacrificed two weeks after benidipine injection, and analyzed using histological sections and CT images. The analysis showed that in the benidipine groups, necrotic bone was reduced, and soft tissue continuity was recovered. Furthermore, the distance between epithelial edges, length of necrotic bone exposed in the oral cavity, necrotic bone area, and necrotic bone ratio were significantly smaller in the benidipine group. These results suggest that a single injection of benidipine in the vicinity of MRONJ-like lesions can promote osteonecrotic extraction socket healing.

Guided bone regeneration membranes are essential for bone formation. While non-resorbable membranes require removal surgery, resorbable membranes such as poly (lactic-co-glycolic acid) PLGA are widely used; however, issues with animal-derived components and degradation control have been identified. A novel bilayer membrane composed of synthetic poly (L-lactic acid-co-ε-caprolactone) (PBM) was developed, offering prolonged degradability and elasticity. This study compared the wound-healing effects of PBM and PLGA membranes in vivo and in vitro experiments. In vivo, maxillary molars were extracted from rats, and membranes were placed over the sockets. Healing was evaluated histologically at 1, 2, 3, 4 and 8 weeks. In vitro, oral epithelial cells and fibroblasts were seeded on both sides of PBM. Adhesion and permeability of the membranes were assessed. In vivo, both groups displayed similar mucosal healing. However, PBM preserved a clear bone-soft tissue boundary. In vitro, the surface of PBM supported significantly greater oral epithelial cell adhesion than the reverse side, with no differences for fibroblasts. Both sides of PBM exhibited better protein permeability compared to PLGA. PBM maintained distinct bone-soft tissue separation in rat extraction sockets, suggesting its potential as an effective space maintainer in guided bone regeneration. Further studies are warranted to investigate the mechanisms underlying these favorable properties.

Background A novel type of implant (Straumann® BLX implant) has been developed for certain stability from the mechanical and biological aspects and is expected for the implant placement in atrophic maxilla with sinus floor elevation (SFE). Purpose The aim of this study was to evaluate the primary stability in the implants with different macrodesigns in a SFE simulated model. Primary stability defined as maximum insertion torque (MIT) and implant stability quotient (ISQ) were compared between this novel type of implant and other types. Materials and Methods Five types of Straumann® 10mm length implants (Standard Plus; SP, Tapered Effect; TE, Bone Level; BL, Bone Level Tapered; BLT and BLX) and two types of Straumann® 6mm length implants (SP short, BLX short) were used in this study. Each Implants were inserted through 5 mm–thick porcine iliac crest blocks (a SFE simulated model). Primary stability was evaluated by using MIT and ISQ. Results The mean values of MIT for BLX group showed significantly higher values than SP, BL (p < 0.01), and TE (p < 0.05) groups. The mean value of ISQ for BLX group was significantly higher than the other groups (p < 0.01). The mean value of MIT and ISQ for BLX and BLX short group were significantly higher than that for SP and SP short group (p < 0.01). Conclusions In a SFE simulated ex vivo model, BLX group showed the highest values. These results suggest that implant selection can play a crucial role in the achievement of primary stability during SFE and simultaneous implant placement.

Guided bone regeneration membranes are essential for bone formation. While non-resorbable membranes re-quire removal surgery, resorbable membranes such as poly (lactic-co-glycolic acid) PLGA are widely used, but has issues with animal-derived components and degradation control. A novel bilayer membrane composed of synthetic poly (L-lactic acid-co-ε-caprolactone) (PBM) was developed, offering prolonged degradability and elasticity. This study compared the wound healing effects of PBM and PLGA membranes in vivo and in vitro experiments. PLGA and PBM membranes were assessed. In vivo, maxillary molars of rats were extracted, and membranes were placed over the sockets. Healing was evaluated histologically at 1, 2, 3, 4 and 8 weeks. In vitro, oral epithelial cells and fibroblasts were seeded on both sides of each membrane. Adhesion and permeability of membranes were assessed. In vivo, both groups displayed similar mucosal healing. However, PBM preserved a clear bone-soft tissue boundary. In vitro, PBM supported significantly greater oral epithelial cells adhesion and higher expression of adhesion proteins compared to PLGA, with no differences for fibroblasts. PBM maintained distinct bone-soft tissue separation in rat extraction sockets, suggesting its potential as an effective space maintainer in guided bone regeneration. Further studies are warranted to investigate the mechanisms under-lying these favorable properties.