Dental management of unilateral multiple impacted primary teeth

Impacted primary teeth can be caused by odontogenic tumors such as odontomas, cystic diseases such as dentigerous and eruption cysts, and fibrous hyperplasia of the gingiva, while elimination of those causes reportedly results in normal eruption of primary teeth. We describe the course of a child from the age of 1 year until 4 years 10 months who had primary tooth eruption failure and was treated with dental methods. Although primary teeth expected to spontaneously erupt were followed, there were several on the left side that remained unerupted. We performed a left maxillary and mandibular gingivectomy to closely examine the cause of eruption delay and tooth germ dislocation, as well as attempt to induce eruption of the primary teeth. Based on histopathological results, the diagnosis was fibroma. Surgical procedures did not result in clear improvement of eruption failure. In order to improve masticatory function and aesthetics, the child was fixed with an artificial denture for all primary teeth not expected to erupt.     

First Japanese case of atypical progeroid syndrome/atypical Werner syndrome with heterozygous LMNA mutation

Atypical progeroid syndrome (APS), including atypical Werner syndrome (AWS), is a progeroid syndrome involving heterozygous mutations in the LMNA gene encoding the nuclear protein lamin A/C. We report the first Japanese case of APS/AWS with a LMNA mutation (p.D300N). A 53‐year‐old Japanese man had a history of recurrent severe cardiovascular diseases as well as brain infarction and hemorrhages. Although our APS/AWS patient had overlapping features with Werner syndrome (WS), such as high‐pitched voice, scleroderma, lipoatrophy and atherosclerosis, several cardinal features of WS, including short stature, premature graying/alopecia, cataract, bird‐like face, flat feet, hyperkeratosis on the soles and diabetes mellitus, were absent. In immunofluorescence staining and electron microscopic analyses of the patient's cultured fibroblasts, abnormal nuclear morphology, an increase in small aggregation of heterochromatin and a decrease in interchromatin granules in nuclei of fibroblasts were observed, suggesting that abnormal nuclear morphology and chromatin disorganization may be associated with the pathogenesis of APS/AWS.     

Fcγ receptor 3B polymorphism is associated with hypersensitivity reactions to adalimumab in Japanese patients with rheumatoid arthritis

Objectives: To examine the association between Fcγ receptor (FcγR) polymorphisms and the development of hypersensitivity reactions to adalimumab in patients with rheumatoid arthritis.

Methods: Sixty-five patients receiving adalimumab were enrolled in the study. Genetic polymorphisms for FcγR3B were genotyped in FCGR3B NA1/2 alleles by real allelic discrimination assay. Clinical information and the occurrence of a hypersensitivity reaction to adalimumab were collected from the patients’ charts.

Results: A hypersensitivity reaction was observed in 12% of the patients. Clinical information obtained from patients with a reaction and those without were the same. The FCGR3B NA1/NA1, NA1/NA2, and NA2/NA2 alleles were found in 75%, 13%, and 13% of the patients with hypersensitivity reaction, respectively, and in 28%, 42%, and 30% of those without a hypersensitivity reaction, respectively (p?=?0.04). Multivariate logistic regression analysis identified only the NA1/NA1 as an independent relevant factor for a hypersensitivity reaction to adalimumab (OR 7.7, p?=?0.01).

Conclusions: The FCGR3B NA1/NA1 genotype is associated with hypersensitivity reactions to adalimumab.     

Development of Innovative Contra-angle Handpiece Device with Piston Movement for Root Canal Preparation

IntroductionThe purpose of this study was to assess the optimal amplitude and weight of the newly developed contra-angle handpiece. The handpiece uses piston movement without using an endodontic motor and enables a safe, quick, and reliable canal preparation.MethodsA prototype handpiece was designed. Instrumentation was performed on root canal resin blocks by 20 operators in 3 groups: the prototype handpiece with an H file (a stainless steel #25 manual H file, the piston group), a manually standardized technique with a K file (stainless steel #15–25 K files, the manual group), and a nickel-titanium (NiTi) reciprocating file with an endodontic motor (Reciproc Blue R25 [VDW, Munich, Germany], the NiTi group). Transportation of the canal center line and the time required for preparation were measured and statistically analyzed.ResultsThe optimal condition was an amplitude of 1.35 mm and a weight of 61.0 g. Transportation of the canal center was observed in all groups. A statistically significant difference was found at 2.0–3.0 mm from the apical foramen between the piston or NiTi group and the manual group, but no significant difference was found between the piston and NiTi groups. The least transportation was found in the NiTi and piston groups. The handpiece with a #25 H file demonstrated a good centering ability, similar to the NiTi file, which enabled speedy preparation. The time required for preparation between the piston or NiTi group and the manual group was statistically different. No significant difference was observed between the piston and NiTi groups (P < .05).ConclusionsWe concluded that the newly designed handpiece achieved efficient canal preparation and negotiation. The handpiece could avoid endodontic accidents, including ledge formation, instrument separation, and perforation.