The Bulletin of Tokyo Dental College Vol. 58(2017) No. 2

A pulpectomy requires the swift extraction of the inflamed tissue. Moreover, the speed of treatment is especially important in the case of uncooperative children. Conventional pulpectomies, however, often require an extended treatment period, which can therefore cause problems with such patients. Electrosurgical methods have been applied to pulpotomies for a number of years. However, to the best of our knowledge, no studies to date have assessed its application to pulpectomies. The aim of this study was to compare clinical and radiographic success rates over a 6-month follow-up period between conventional and electrosurgical pulpectomies. A total of 50 children aged 4 to 8 years were enrolled in this randomized clinical trial. A pulpectomy of the first and second primary molar teeth was seen as the optimal treatment plan in all these patients. One group was treated using the conventional method (C group, 25 teeth) and the other with electrosurgery (ES group, 25 teeth). The patients were evaluated for the presence of pain, mobility, abscess, sinus tract, erythema, tenderness to percussion, internal and external root resorption, and radiolucency. Clinical and radiographic success rates and total working time were assessed. The Fisher's exact test and Mann-Whitney U-test were used for the statistical analysis. After 6 months of follow-up, the clinical and radiographic success rates were 90.5 and 85.7%, respectively, in the ES group, compared with 88.9 and 72.2%, respectively, in the C group. No statistically significant difference was observed between the two groups (p>0.05). Working time, however, was significantly shorter in the ES group (p<0.001). This suggests that pulpectomy with electrosurgery reduces treatment time, and is therefore quite useful in situations where duration of the treatment course is of crucial concern.

The purpose of this study was to identify which factors were associated with number of present teeth (PT) in older adults as their clarification might contribute to maintaining the number of PT in this population. These factors were investigated by means of a questionnaire on oral health condition, general health behavior, and anamnesis of diabetes mellitus together with a dental examination. Data were obtained from a total of 7,741 Japanese subjects (2,623 males and 5,118 females), all of whom were aged 40, 50, or 60 years. Significant differences were observed in the mean number of PT between a positive or negative response to questions on anamnesis of diabetes mellitus, current smoking, and having loose teeth in all age groups in males; significant differences were also observed for current smoking, lower intake of dairy milk products, having loose teeth, no experience of tooth brushing instruction, and poor oral hygiene status in all age groups in females. Stepwise logistic regression analysis revealed having loose teeth (odds ratio [OR], 1.82), gingival swelling (OR, 1.40), an anamnesis of diabetes mellitus (OR, 1.72), current smoking (OR, 1.86), lower intake of dairy milk products (OR, 1.22), preference for salty seasonings (OR, 1.23), frequent sweet intake (OR, 1.29), no experience of tooth brushing instruction (OR, 1.38), and poor oral hygiene (OR, 2.04) as significant risk factors for the number of PT being <24 after adjusting for age and sex. These results indicate that an anamnesis of diabetes mellitus, a history of smoking, the presence of loose teeth, and poor oral hygiene status in a self-reported evaluation of oral health might correlate with <24 PT in older adults.

Although the risk of injuring the lingual nerve in the mandibular molar area during dental treatment is high, it can be repaired by nerve grafting. However, from the perspective of clinical dentistry, the pathway and histomorphometric characteristics of this nerve remain to be documented in detail. The purpose of the present study was to morphologically elucidate the pathway of the lingual nerve to clarify its significance in a clinical setting. A histomorphometric analysis was also performed in consideration of nerve grafting. The vertical distance between the occlusal plane and the superior margin of the lingual nerve showed a gradual decrease from the premolar toward the distal molar area. This suggests that the risk of injuring the lingual nerve increases gradually toward the distal area. The average total fascicular area of the lingual nerve was 1.90 mm², which was larger than that of the sural nerve. It is the first-choice donor nerve for grafting. Therefore, even though the total fascicular area of the donor nerve is a little smaller than that of the recipient nerve, nerve grafting should be successful.

The purpose of this study was to compare the antibacterial properties of Azadirachta indica (neem) or Curcuma longa (turmeric) against Enterococcus faecalis with those of 5% sodium hypochlorite or 2% chlorhexidine as root canal irrigants in vitro. The activity of neem, chlorhexidine, sodium hypochlorite, or turmeric against E. faecalis was measured on agar plates using the agar diffusion method. The tube dilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the irrigants used. Chlorhexidine or neem exhibited the greatest antibacterial activity when used as endodontic irrigants against E. faecalis, followed by sodium hypochlorite. No statistically significant difference was observed between neem, sodium hypochlorite, or chlorhexidine. The MIC of neem was 1: 128, which was similar to that of chlorhexidine. The MBC for each of these irrigants was 1: 16. Neem yielded antibacterial activity equivalent to 2% chlorhexidine or sodium hypochlorite against E. faecalis, suggesting that it offers a promising alternative to the other root canal irrigants tested.

The purpose of this study was to investigate the relationship between interdental spacing in the upper incisors and other associated factors with colonization by Streptococcus mutans in children. A total of 47 children aged between 24 and 36 months with no decayed cavities were enrolled in the study. Models were obtained to evaluate interdental spacing in the upper anterior region. The relationships between S. mutans colonization and number of erupted teeth, interdental spacing, diet, and oral hygiene behavior were investigated. S. mutans was detected in the saliva of 14 children (29.8%). No sociodemographic variable was associated with colonization by S. mutans. Neither number of erupted teeth nor children's age showed an influence on colonization by S. mutans. However, children with interdental spacing in the upper incisors were less likely to show colonization by S. mutans (15.8%) than those without (39.3%). Furthermore, children who ceased breast-and/or bottle-feeding by 15 months of age were less likely to show colonization by S. mutans (22.7%) than those who continued feeding until 19 months of age or more (46.2%).

The wax sculpting of a maxillofacial prosthesis is challenging, time-consuming, and requires great skill. Rapid prototyping (RP) systems allow these hurdles to be overcome by enabling the creation of a customized 3D model of the desired prosthesis. Geomagic and Mimics are the most suitable software programs with which to design such prostheses. However, due to the high cost of these applications and the special training required to operate them, they are not widely used. Additionally, ill-fitting margins and other discrepancies in the final finished products of RP systems are also inevitable. Therefore, this process makes further treatment planning difficult for the maxillofacial prosthodontist. Here, we report the case of a 62-year-old woman who attended our clinic. Initially, she had presented with a right facial defect. This was later diagnosed as a squamous cell carcinoma and resected. The aim of this report is to describe a new technique for the 3D printing of facial prostheses which involves the combined use of open-source software, an RP system, and conventional methods of fabrication. The 3D design obtained was used to fabricate a maxillofacial prosthesis to restore the defect. The patient was happy with the esthetic outcome. This approach is relatively easy and cheap, does not require a high degree of non-medical training, and is beneficial in terms of clinical outcome.

Swelling of the cervical lymph nodes may indicate lymphadenitis, malignant lymphoma, or metastasis. Lymph nodes larger than 10 mm on computed tomography (CT) are strongly indicative of postoperative metastasis from carcinoma. Here, we report a case of large, inflamed lymph nodes mimicking metastasis. The patient was a 76-year-old woman who experienced discomfort in the left-side maxillary gingiva commencing in August 2011. By September, the area had become painful, causing her to visit the Tokyo Dental College Chiba Hospital, at which time a 75×50-mm swollen ulcer was observed in the maxillary gingiva on the left side. A CT image revealed a neoplastic lesion between the alveolar bone on the left side of the maxilla and the base of the maxillary sinus, together with evidence of osteoclastic activity. The bilateral cervical lymph nodes were Level II and had a uniform interior of approximately 5 mm. The lesion was subsequently excised under general anesthesia. At 34 days postoperatively, CT imaging revealed bilateral 40-mm internal heterogeneous lymphadenopathy at Level II. No inflammation of the maxillary gingiva was observed, however, and blood tests revealed no inflammatory findings. Bilateral cervical lymph node metastasis was diagnosed based on CT and oral cavity observation. Radical neck dissection of left cervical region was performed under general anesthesia. Histopathological examination of the lymph nodes revealed no metastasis at Levels I–V, however. The reason for this increase in lymph node size is discussed.