Various types of bracket are currently available, and different prescriptions are provided for the same type of tooth. There are no definite criteria, however, on which to base bracket selection. The purpose of this study was to investigate differences in the angulation and inclination of orthodontically aligned teeth when using different prescription brackets. Thirty patients undergoing orthodontic treatment for maxillary protrusion and crowding were enrolled. After orthodontic treatment with a pre-adjusted appliance, angulation and inclination were measured on dental casts obtained from these patients (10 each with 0.022 MBT, 0.022 Roth, or 0.018 Roth brackets). The dental casts were scanned and digitized using a 3-dimensional (3-D) scanner and measured with 3-D model measurement software. A significant difference was observed in the mean angulation of the mandibular canine between the 0.022 MBT (5.81°) and 0.018 Roth groups (9.07°). Greater mesial inclination was observed in the 0.018 Roth group. No significant difference was observed in any of the other regions measured. Differences in bracket prescription showed no clinical influence on treatment outcomes. A significant difference was observed in the mandibular canine (p<0.05), suggesting that consideration is required when selecting brackets.

The purpose of this methodological study was to clarify intra- and inter-investigator reliability of lip-seal strength measurement in adults. Lip-seal strength was measured with a digital medical strain gauge using the button-pull method. The coefficient of variation (CV) of intra-investigator reliability of measurement in 24 healthy adult volunteers (16 men, 8 women; mean age, 26±3 years) ranged from 0.088 to 0.103 (mean for 3 investigators, 0.098). The intraclass correlation coefficient (ICC [1,1]) of intra-investigator reliability of this method of lip-seal strength measurement ranged from 0.759 to 0.832 (mean, 0.804). The ICC (2,1) of inter-investigator reliability of the measured values was 0.737. The CV of intra-investigator reliability of lip-seal strength measurement by a single investigator in 54 adult patients (14 men, 40 women; mean age, 49±16 years) was 0.072. The ICC (1,1) of intra-investigator reliability of this measurement method of lip-seal strength was 0.863. A CV of approximately 0.2 or lower is considered to indicate excellent agreement; an ICC of approximately 0.75 or higher is considered indicative of good reliability. These results demonstrate that measurement of lip-seal strength in adults with this device offers sufficient intra- and inter-investigator reliability.

The purpose of this cross-sectional study was to determine whether there is an association between hemoglobin A1c (HbA1c) level and the presence or absence of decayed teeth in patients with type 2 diabetes mellitus. The patients and data on their age and sex, the presence or absence of dental claims, medical history of diabetes mellitus, and workplace dental examinations were obtained from a Japanese healthcare database available for epidemiological studies. The HbA1c levels were obtained from results of the Specific Health Checkups and Specific Health Guidance tests conducted by the Japanese Ministry of Health, Labour and Welfare. Data on a total of 1,897 patients were analyzed. Patients with poorly controlled diabetes (HbA1c≥6.5, n=779) had more decayed teeth than those in whom it was well controlled (HbA1c<6.5, n=1,118). Multiple logistic regression analysis with the presence or absence of decayed teeth as a dependent variable revealed a significant association between an HbA1c level of ≥8.0 and decayed teeth (odds ratio: 1.69; 95% confidence interval, 1.24–2.29), even after adjusting for dental attendance. This suggests that a poorly controlled blood HbA1c level is a risk factor for dental caries. More thorough oral hygiene instruction and education on preventive treatment for dental caries in patients with poorly controlled diabetes are needed.

Here, we describe the treatment course and 2-year follow-up in a case of multiple deep intrabony defects treated with periodontal regenerative therapy. The patient was a 50-year-old woman presenting with the chief complaint of mobile teeth in the maxillary molar region. Examination at her initial visit revealed sites with a probing depth of ≥7 mm in the molar region. Radiographic examination revealed generalized bone resorption. Angular bony defects were evident in the molar region. Initial periodontal therapy was commenced based on a clinical diagnosis of generalized chronic periodontitis. At re-evaluation, an improvement was observed in periodontal conditions. Periodontal regenerative therapy with enamel matrix derivative was performed on teeth #13, 15, 24, 27, 33, 35, 37, 46, and 47. Following re-evaluation, a removable partial denture was used to replace teeth #26 and 45, and the patient placed under supportive periodontal therapy. Periodontal conditions have remained stable. Careful supportive periodontal therapy needs to be continued, however, to monitor and treat sites requiring further attention, including those with furcation involvement.

Many studies have investigated the relationship between periodontal disease and the onset of peri-implantitis. It is important to devise practical measures for preventing the development of peri-implantitis in patients with periodontal disease if the success of implant treatment is to be secured. Here, we report the role of the superstructure in two cases of implant treatment in patients with severe periodontal disease. Both patients had severe periodontitis and underwent implant treatment after improving the state of the disease, thereby ensuring that the implant superstructure could be maintained. Both cases remained stable after implant treatment. The results indicate that proper periodontal treatment prior to implant treatment leads to long-term success. In addition, it is necessary to use an implant superstructure that reduces plaque accumulation in preventing peri-implantitis.

Here, we report two cases of dental bimaxillary protrusion in which orthodontic anchor screws were used to improve the esthetics of the mouth and lips and facilitate complete closure of the mouth. Case 1 was a woman with dental maxillary protrusion and constriction of the dental arches, with the main complaint of protrusion of the lips and mandibular crowding. The maxillary and mandibular dental arches were first widened and traction applied to the maxilla via orthodontic anchor screws. The maxillary incisors were retracted 10 mm and the mandibular incisors 3 mm, resulting in upper lip retraction of 3 mm and bottom lip retraction of 5 mm with respect to the E-line. The nasolabial angle increased to 20°, and the inter-vermilion angle, which indicates the thickness of the vermillion, decreased to 20°, improving esthetics by reducing the thickness of the lips. Case 2 was a woman with bimaxillary dental protrusion, with the chief complaint of protruding lips and a gummy smile. Orthodontic anchor screws were used to achieve posterior traction and intrusion in the maxillary incisor region to improve the gummy smile. The maxillary incisors were retracted 9 mm and the mandibular incisors 8 mm. In the soft tissues, this yielded upper lip retraction of 3 mm and bottom lip retraction of 4 mm with respect to the E-line. The nasolabial angle increased to 10° and the inter-vermilion angle decreased to 30°, improving esthetics by reducing the thickness of the lips. The gummy smile was also improved, with 4 mm intrusion of the maxillary incisors. Increased ease in closing of the mouth was also a major factor in patient satisfaction with the results of orthodontic treatment.

Here, we report periodontal treatment including regenerative therapy in a patient with generalized chronic periodontitis. The patient was a 53-year-old woman who presented with the chief complaint of gingival swelling and tooth mobility in the right maxillary molar region. An initial examination revealed 36% of sites with a probing depth of ≥4 mm and 15.5% with bleeding on probing. Radiographic examination revealed vertical bone resorption in #15, 24, 27, 34, 37, 45, and 47. Horizontal resorption was noted in other regions. The clinical diagnosis was moderate chronic periodontitis. Initial periodontal therapy consisted of plaque control, scaling, and root planing together with treatment for caries. Occlusal adjustment of premature contact sites was performed after suppression of inflammation. Periodontal regenerative therapy using enamel matrix derivative was performed on #15, 24, 34, 45, and 47. Other sites with residual periodontal pockets were treated by open flap debridement. Tooth #27 was extracted due to a bone defect exceeding the root apex; #37 was extracted due to frequent acute symptoms following periodontal surgery. Following re-evaluation, the patient was placed on supportive periodontal therapy. Periodontal regenerative therapy improved vertical bone resorption. This improvement has been adequately maintained over a 3 years 6 months period. Additional care is necessary, however, to further improve the patient's oral health-related quality of life during supportive periodontal therapy.

Here, we report retention following surgical orthodontic treatment in a patient with vertical maxillary excess associated with temporomandibular joint osteoarthritis (TMJOA) and marked mandibular retrusion. The patient was a man aged 20 years 10 months who presented with the chief complaint of maxillary protrusion. The facial profile was of the convex type due to marked mandibular retrusion. In addition, the patient had a gummy smile. Intraoral findings revealed a Class II molar relation, +11 mm overjet, and 0 mm overbite. Mandibular dentition arch length discrepancy showed crowding of −2 mm, and the maxillary dentition showed a spaced arch of +5 mm. Panoramic radiographs confirmed flattening of the condylar head and proliferation of the bone margin. Cephalometric analysis of the skeletal pattern revealed that, horizontally, the maxilla was anterior and the mandible posterior; vertically, a dolichofacial pattern was noted. The anterior maxillary tooth axis was standard, but the anterior mandibular tooth axis showed labial inclination. Based on these findings, skeletal maxillary protrusion associated with TMJOA was diagnosed. Surgical orthodontic treatment comprised bilateral mandibular first premolar extraction with two-jaw surgery and genioplasty. Orthodontic treatment was performed with a multibracket system using a 0.22-slot pre-adjusted edgewise appliance. At 2 years and 11 months after initiation of treatment, the maxilla was transposed 6 mm upwards by orthognathic surgery and the mandible 17 mm anteriorly and 5 mm upwards by counterclockwise rotation. At 3 years and 10 months, the Pogonion was moved 6 mm anteriorly by genioplasty. At 4 years, orthodontic treatment was concluded on confirming satisfactory occlusion and improvement in facial features. At 2 years after completion of treatment, occlusion and the maxillofacial morphology remain stable, with almost no relapse. In addition, no temporomandibular joint disorder symptoms have occurred. Careful comprehensive follow-up observation will be continued.