The objective of this study was to clarify the influence of improvement in morphology on chewing movement in patients with skeletal reversed occlusion following orthognathic treatment. A total of 10 patients with skeletal class III reversed occlusion undergoing orthognathic treatment were included in the study. A number of parameters, including chewing rhythm, maximum opening and closing velocities, and opening distance during chewing of gum, were measured in a pre- (Pre) and post-treatment (Post) group. The laterality and stability of the measured items were then compared between the two groups and with those in another group of subjects with normal occlusion (Control). Laterality of chewing movement was greater in the Pre group than in the Control group, and significant differences were noted in all parameters, apart from closing Vmax and opening distance. No significant difference was noted in any parameter between the Post and Control groups. The coefficient of variation was significantly higher in the Pre group than in the Control group, apart from for opening phase. All parameters showed a significant decrease in the Post group compared with in the Pre group, yielding a stable chewing movement. Comparison of the Post and Control groups revealed no significant difference in any of the parameters, apart from in the occluding phase. These findings suggest that orthognathic treatment of skeletal class III malocclusion improves chewing movement to levels close to those in subjects with normal occlusion.

The purpose of this study was to investigate whether number of non-vital teeth was an indicator of tooth loss during maintenance. Thirty-three general practitioners provided data on 321 patients undergoing maintenance over 10 years. The number of present teeth (PT), smoking status, level of bone loss, number of non-vital teeth, and reason for tooth loss during that period were investigated. Multiple logistic regression was performed to identify whether the number of non-vital teeth was associated with tooth loss. The average number of lost teeth was 1.07±1.82; that of PT at baseline was 24.4±3.9; and that of non-vital teeth at baseline was 5.4±4.5. Multiple logistic regression revealed a significant association between >8 non-vital teeth and tooth loss during maintenance (odds ratio [OR]: 2.40; 95% confidence interval [CI]: 1.18–4.87). It also demonstrated relationships between >8 non-vital teeth and root fracture or caries (OR: 3.90; 95%CI: 1.68–9.03 or OR: 2.85, 95%CI: 1.14–7.10, respectively). The number of non-vital teeth was associated with tooth loss during maintenance. The results suggest that patients with many non-vital teeth before commencement of maintenance are particularly at risk of tooth loss due to root fracture or caries. Therefore, the number of non-vital teeth offers a useful indicator of potential tooth loss.

The purpose of this prospective, randomized, double-blind, placebo-controlled study was to determine the effect of preoperative oral administration of ibuprofen or dexamethasone on the success rate of inferior alveolar nerve block (IANB) in patients with symptomatic irreversible pulpitis. Seventy-eight patients with irreversible pulpitis were randomly divided into 3 groups (26 per group) and given one of the following at 1 hr prior to performing local anesthesia: a placebo; 400 mg ibuprofen; or 4 mg dexamethasone. Each patient recorded their pain level on a visual analog scale before taking the medication or placebo, at 15 min after completion of IANB, and during treatment if pain occurred. The success of the anesthesia was defined as no or mild pain at any stage during the endodontic procedure. The success rate of the IANB was 38.5, 73.1, and 80.8% with the placebo, ibuprofen, and dexamethasone, respectively. Both ibuprofen and dexamethasone were significantly more effective than the placebo. No significant difference was observed, however, between the two experimental medications in terms of effectiveness. The results of the present study suggest that premedication with ibuprofen or dexamethasone increases the success rate of an IANB in patients with symptomatic irreversible pulpitis in the mandibular molars.

A 60-year-old woman presented with the chief complaint of mobility of tooth #16. Gingival swelling and calculus were observed. Clinical examination revealed that 49.4% of sites had a probing depth (PD) of ≥4 mm and 72% of sites bleeding on probing. Radiographic examination revealed vertical bone resorption in #35 and horizontal resorption in other regions. Periapical region radiolucency on #16 and 27 suggested a perio-endo lesion. The clinical diagnosis was severe chronic periodontitis. Initial periodontal therapy mainly comprised the following: oral hygiene instruction; quadrant scaling and root planing (SRP); extraction of #16, 27, and 31; and placement of provisional restorations. Open flap debridement was performed for teeth with a PD ≥4 mm. Bone defects exceeding the root apex were found in #17, 41, 42, and 45 intraoperatively. Teeth #41, 42, and 45 were extracted. After confirming the stability of the periodontal tissue, final prostheses were placed on #14–17, 13–22, 35–37, 33–43, 44–46, and 47. Following reevaluation, the patient was placed on supportive periodontal therapy (SPT). After 6 years, the patient experienced dull pain in and pus discharge from #17. Repeated SRP yielded no improvement, so the tooth was extracted and a removable partial denture placed on #16 and 17. Nine years have passed since the start of SPT and the level of plaque control has remained adequate and periodontal condition stable.

We report the successful morphological correction of a maxillary lateral incisor with a talon cusp and the preservation of vital pulp by employing an intentional partial pulpotomy. A talon cusp is a comparatively rare morphological tooth anomaly that may cause multiple clinical problems. An 11-year-old girl was referred to our department for morphological correction of a maxillary lateral incisor with a talon cusp prior to orthodontic treatment. Following a detailed CT examination of the interior morphology, the abnormal cusp was resected and an intentional partial pulpotomy performed. Five years postoperatively, the tooth showed no abnormalities. These results indicate that an intentional partial pulpotomy following a detailed CT examination is effective in correcting complicated morphological anomalies such as a talon cusp containing extended dental pulp.

The eruption of a tooth into the nasal cavity is a rare clinical entity. We report a case of an inverted supernumerary tooth in the nasal cavity. A 2-year-old boy was referred to our institution after examination at a local otorhinolaryngology department for otitis media. Radiological examination revealed a tooth-like structure in the right nasal cavity. The tooth was protruding from the floor of the nasal cavity along with granulation tissue. The diagnosis was an inverted tooth in the right nasal cavity. Forceps extraction was performed under general anesthesia.

We performed orthodontic treatment, fitted prostheses, and provided restorative treatment in a patient with Bloch-Sulzberger syndrome and cleft lip and palate during the early mixed dentition period. We report the case after a subsequent 6-year retention phase including the period of pubertal growth. A girl aged 8 years 4 months visited our hospital with the chief complaint of crowding of the anterior teeth and anterior crossbite. She had bilateral cleft lip, alveolus, and palate; a Class II molar relationship; winging of both the maxillary bilateral central incisors; and spacing in the mandibular anterior teeth arches. Anterior crossbite comprised 0 mm overbite and −1 mm overjet. The crown diameter was at least one standard deviation smaller than normal in both the deciduous and permanent teeth, and the crowns were slightly peg-shaped. Panoramic radiograph confirmed congenital absence of 21 permanent teeth. Cephalometric analysis revealed poor growth of the maxilla, downward growth of the mandible, and lingual inclination of the maxillary central incisors. The diagnosis was skeletal anterior crossbite with cleft lip, alveolus, and palate, accompanied by hypodontia. Orthodontic treatment comprised an edgewise appliance and an expansion arch to improve crowding and anterior crossbite. The appliance was removed 2 years after treatment initiation, followed by crown restorations of the maxillary central incisors and mandibular deciduous anterior teeth. A metal retainer was then fitted to the maxillary dentition. She was subsequently placed in a 6-year retention phase including pubertal growth, during which occlusal stability and esthetics were maintained.

The purpose of this study was to investigate three-dimensionally temporal change in flap volume after free flap reconstructive surgery in tongue cancer patients. The results revealed an average change in flap volume of 82.3% at 1 year postoperatively. Change in tongue volume at approximately 6 months postoperatively showed a correlation with triglyceride levels. A correlation was also found between albumin levels and tongue volume at 1 year onwards postoperatively. The goal of such surgery in patients with tongue cancer is to reconstruct a functional tongue. Taking postoperative change in tongue volume into consideration is therefore of importance in minimizing postoperative dysphagia.