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Objective: Intraoral scanner (IOS) can acquire three‐dimensional color images of teeth. Thus, the detection of areas with plaque adhesion stained by plaque‐disclosing solutions using an IOS could be a potential oral hygiene evaluation method. This study aimed to verify the usefulness of obtaining O'Leary's plaque control record (PCR) measurements using an IOS in clinical practice. Methods: Twenty patients with >20% PCR measurements who underwent oral prophylaxis were enrolled in this study. A plaque‐disclosing gel was applied to stain the areas with plaque adhesion, and the dentition was scanned using the IOS. The PCR values obtained via the direct method and those obtained using the digital image were compared for the entire dentition, maxillary total area, the labial and palatal aspects of the maxillary anterior teeth, the buccal and palatal aspects of the maxillary posterior teeth, mandibular total area, the labial and lingual aspects of the mandibular anterior teeth, and the buccal and lingual aspects of the mandibular posterior teeth. Results: The IOS group tended to have higher values than the direct observation group. The labial and palatal aspect of the maxillary anterior teeth, the labial and lingual aspects of the mandibular anterior teeth did not differ significantly between the groups. Conclusion: Plaque adhesion was visualized easily and conclusively using an IOS. As the large tip size often hinders its use, it is necessary to develop a smaller IOS tip in the future. [ABSTRACT FROM AUTHOR]

Acid bone lysates (ABLs) represent the growth factors and other molecules released during autologous graft resorption. However, the impact of these bone‐derived growth factors on the healing of bone defects has not yet been investigated. The aim of the present study was, therefore, to examine the impact of ABLs adsorbed to collagen membranes on bone regeneration. To this end, in 16 female Sprague Dawley rats, a standardized 5‐mm‐diameter critical size defect on the calvarial bone was created. The defects were covered with collagen membranes that had been soaked either in serum‐free media or ABLs followed by lyophilization. After a healing period of 4 weeks, micro‐computed tomography (μCT) and histological analyses by means of undecalcified thin ground sections were performed. μCT analysis of the inner 4 mm of the calvaria defect showed a greater bone defect coverage in the control group when compared to ABL group, 29.8% (confidence interval [CI]: 17.7–50.3) versus 5.6% (CI: 1.0–29.8, p =.03), respectively. Moreover, we found significantly more absolute bone volume (BV) in the control group when compared to ABL group, 0.59 mm3 (CI: 0.27–1.25) versus 0.07 mm3 (CI: 0.06–0.59, p =.04), respectively. Histomorphometry confirmed these findings with a relative BV in the central compartment of 14.1% (CI: 8.4–20.6) versus 5.6% (CI: 3.4–7.9, p =.004), respectively. These findings indicate that bone‐derived growth factors contained in ABLs are able to attenuate bone regeneration within collagen membranes. [ABSTRACT FROM AUTHOR]

Background: MicroRNAs (miRNAs) are small noncoding RNAs demonstrated as critical post-transcriptional modulators in dental tissues and bone regeneration, particularly miR-21-5p. However, the role of miR-21-5p in the healing of alveolar sockets following tooth extraction remains unknown. In this study we evaluated the influence of miR-21-5p in the healing of alveolar socket after tooth extraction.Methods: Eight miR-21-5p knockout mice and eight littermate controls underwent tooth extraction of the upper right incisor. After a healing period of 14 days microCT and histological analyses were performed.Results: MicroCT analysis showed that the percentage of bone in the extraction socket was significantly higher in the control group than in the miR-21 knockout mice; either in the coronal (39.0%, CI 31.8 to 48.0 versus 23.0%, CI 17.8 to 35.2, P = 0.03) or in the middle part of the alveolar socket (56.0%, CI 50.9 to 62.5 versus 43.5% CI 28.6 to 54.6, P = 0.03). These differences were not noted in the apical part of the extraction socket. Histological analysis supported the microCT findings. Newly bone volume per tissue volume (BV/TV) was significantly higher in the control group when compared to miR-21 knockout mice, 27.4% (CI 20.6 to 32.9) versus 19.0% (CI 14.7 to 21.5, P < 0.05), respectively. Surprisingly, no evident signs of buccal bone resorption were observed in both groups.Conclusion: Despite the limitation of one observation period, these findings suggest that miR-21-5p delays the early healing of alveolar socket following tooth extraction. Whether miR-21-5p is essential for healing of alveolar sockets remains to be elucidated. [ABSTRACT FROM AUTHOR]

Background: After bone resection surgery, bone defects accompanied with loss of teeth, it is required not only bone reconstruction but also occlusal function by prosthesis such as dental implant. The authors have revealed that novel porous titanium (Ti) has good mechanical strength and osteoconductivity because of three‐dimensional structure. Aim/Hypothesis: The purpose of this study was to evaluate the osseointegration abilities of implants placed in novel porous Ti. Material and Methods: For the bone reconstruction material, porous Ti (φ6 mm in outer, φ2 mm in inner diameter × 4 mm, hollow cylindrical shape) fabricated by Ti impregnation technique. The same shape of porous hydroxyapatite was used as control. Bone defect (φ6 mm × 4 mm) were prepared in both femurs of male New Zealand White rabbits (17 weeks old) and each graft material was placed (_I_n_i_ = 4). Four weeks after first surgery, an implant socket was prepared in the hollow part of the graft material, and a pure Ti implant (φ2 mm × 4 mm) was implanted. Four weeks after implantation, non‐decalcified specimens were prepared, and toluidine blue staining was applied. We performed the histological observation and histomorphometric evaluations, bone formation ratio and bone implant contact ratio (BIC) (_I_n_i_ = 4). All data were statistically analyzed at the 5% significance level using Student's _I_T_i_ test. (Approved by Hiroshima University animal experiment ethics committee‐ A11‐5‐5.) Results: New bone formation was observed in both groups, and there is no significant difference in bone formation ratio. Also, osseointegration was observed at the bone‐implant interface, and BIC was also no significant difference. Conclusions and Clinical Implications: Novel porous Ti has good mechanical strength and enough for bone formation scaffold. Moreover, it could be able to achieve osseointegration at bone reconstructed site by the porous Ti. [ABSTRACT FROM AUTHOR]