The bonding of indirect restorations with crowns and prostheses has many benefits not only in restoring morphology and function, but also in prolonging tooth life and preventing disease. The adhesive bonding of restorations is affected by the two bonding surfaces of the adhesive resin cement, the abutment side and the restoration side, as well as the physical properties of the resin cement itself. The bonding surfaces on the abutment side can be enamel, dentin, metal, or composite resin, depending on the case. On the other hand, those on the restoration side are diverse, including metals (precious and non-precious), ceramics (glass and zirconia), and resin-based materials such as composite resins, CAD/CAM crown materials, and PEEK materials. Differences in characteristics of the bonding surfaces must be taken into consideration.

口腔インプラント，早期荷重 Biophysical stimulation with heat, pressure, sound waves, electromagnetic waves, and electric currents can restore dysfunction, reduce pain, and induce tissue healing. The research group the authors are affiliated with began this new research in the early 1990s with the hypothesis that biophysical stimulation could significantly shorten the healing time of oral implants. Several studies conducted by the authors over three decades suggests that Pulsed Electromagnetic Field stimulation (PEFMs), Capacitively Coupled Electric Field stimulation (CCEF), and Low-intensity Pulsed Ultrasound (LIPUS) may promote osseointegration earlier than under generic conditions that do not involve any external stimulations. LIPUS for early loaded implants in a multicenter clinical study had relatively better clinical results than generic conditions. Therefore, LIPUS is a biophysical stimulation method that can achieve good results in bone formation with a relatively short 15-20 minute session in a day.

The accuracy of the fit of the superstructure is important for the long-term maintenance and stability of implant prosthetics. We carried out an X-ray study to investigate errors in impression taking of implant superstructures in order to obtain highly accurate impressions for fabrication of implant prostheses. To measure the error in implant impressions using digital X-rays, we made models fixed to a plastic plate with an artificial gap of 50 µm and 100 µm thick strips between the impression coping and the implant fixture and that without the artificial gap. These models were scanned at angles ranging from 0°-25° in the horizontal direction with respect to the platform. Charge-coupled device (CCD) and imaging plate (IP) sensors were used for comparison. The CCD images tended to be superior to the IP images in terms of the visualization limit. On the IP images, there was no major change in the proportion of reviewers who overlooked the presence of a gap in accordance with different angles of irradiation. The CCD tended to perform better than the IP at irradiation angles of 15° or less, but the IP tended to perform better at irradiation angles of 20° or more. It is important to check the fit between the implant fixture and the abutment using X-rays from the correct irradiation angle to reduce the error.

The success rate of endodontic treatment is greatly improved by the use of the "three sacred tools of endodontics": the dental CBCT, the microscope, and the Ni-Ti file. In addition, the accuracy of endodontic treatment can be greatly enhanced by improving the accuracy of preoperative examination and diagnosis and by following basic protocols in an aseptic environment. In this article, we present two cases of endodontic treatment in which the diagnosis was made according to the guidelines of the American Association of Endodontists (AAE). One is a case of pulp preservation, and the other involves an endodontic-periodontal lesion. Through these cases, I would like to review the procedures focused on the preservation of a single tooth revisiting the basic techniques.

This report is to present a case of a patient with a severe gummy smile who was successfully treated by orthodontic aligners and crown lengthening. The patient, a 26-year-old female, presented to our hospital with a chief complaint of gingival exposure in a high smile. The gingival exposure in a high smile was about 7 mm, and she had a pronounced overbite and altered passive eruption. The anterior teeth were tipped in an inclined position by orthodontic treatment. Relative intrusion by 2 mm was achieved, followed by absolute intrusion by 1mm in the axial direction. The patient's facial appearance was reevaluated, and orthodontic fine-tuning was performed again. After orthodontic treatment, the patient's facial appearance was reevaluated and the amount of gingival resection was determined based on CT scan images and dental models, and crown lengthening was performed. The gum exposure in a high smile, which was her chief complaint, was improved and satisfactory results were obtained.

This is a case report of occlusal reconstruction for a patient with attrition. Case Summary: The 75-year-old male with a chief complaint of pain due to the ill-fitting denture and worn anterior teeth. The patient had a removable partial denture in the missing maxillary left molar region and bridges in the other missing parts, but they did not fit and secondary caries were observed. In addition, half of the crowns of the upper and lower anterior teeth were worn away. Treatment plan and course: After performing bite raising with anterior mock-up and molar provisional restorations and confirming that there were no functional problems, implants were placed in the molar regions and occlusal reconstruction was performed. Discussion: When treatment involves drastic changes in the oral cavity, such as occlusal reconstruction in the elderly, it is an issue whether the patients themselves can adapt to such changes. In this case, we believe that the use of easily retractable intervention, namely, the intraoral mockup directly attached to the natural teeth in the anterior region without grinding, served well and led to minimization of the tooth material removal.

In order to guide toward sound occlusal development in a pediatric patient with mixed dentition presenting malocclusion, it is important to understand how the malocclusion developed and to eliminate the causes. In this report we discuss the possibilities and limitations of MFT through the case studies. We found that pediatric patients for whom oral myofunctional therapy (MFT) proved effective shared certain common traits other than functional and morphological characteristics. The results of this study suggest that the use of MFT in the development of occlusion can be enhanced by collecting information from the standpoint of the dental hygienist, based on the assumption that orthodontic diagnosis and examination were performed properly.