Shunsuke Namaki

Videofluorographic evaluation of dysphagia before and after modification of the flap and scar in patients with oral cancer

Abstract Dysphagia is an important postoperative problem in patients with oral cancer. We evaluated the usefulness of a technique to modify the flap and scar for the alleviation of swallowing disorders. The modifications were made while tongue pressure was being measured to improve excursion of the residual tongue in nine patients. They had been operated on for oral cancer and reconstruction was with a forearm free flap, or the wound was closed primarily. After a 5 ml bolus of liquid barium had been given orally, lingual movement, barium inflow into the pharynx before swallowing, stasis in the epiglottic valleculae, and stasis in the oral cavity after swallowing, were evaluated by videofluorography before and after modification. Oral transit time, pharyngeal transit time, and total transit time were also measured. Lingual movement improved in eight patients. Barium inflow into the pharynx before swallowing improved slightly in all patients. Stasis in the epiglottic valleculae was improved in six patients. Stasis in the oral cavity improved in all patients. Oral transit time and total transit time were significantly shorter after modification of the flap and scar than before operation. Pharyngeal transit time was unchanged. We conclude that our technique for modification of the flap and scar can alleviate postoperative swallowing dysfunction in patients with oral cancer.

Current status of implant prosthetics in Japan: a survey among certified dental lab technicians

BackgroundThere are many implant cases in which dental technicians take initiative with regard to the design of implant prostheses, and to a certain extent, this area of care is one in which dentists do not necessarily play the leading role. Moreover, inadequate communication between dental technicians and dentists and insufficient instructions for technicians has been highlighted as issues in the past. The purpose of this questionnaire is to improve the quality of implant prostheses and thereby contribute to patient service by clarifying, among other aspects of treatment, problem areas and considerations in the fabrication of implant prostheses, conceptual-level knowledge, and awareness of prosthodontics on the part of the dentists in charge of treatment and methods for preventing prosthetic complications.MethodsA cross-sectional survey was given to 120 certified dental technicians. To facilitate coverage of a broad range of topics, we classified the survey content into the following four categories and included detailed questions for (1) the conditions under which implant technicians work, (2) implant fixed prostheses, (3) implant overdentures, and (4) prosthetic complications.ResultsOut of 120 surveys sent, 74 technicians responded resulting in a response rate of 61.6%.ConclusionsThis survey served to clarify the current state of implant prosthodontics, issues, and considerations in the fabrication of implant prostheses, and the state of prosthetic complications and preventive initiatives, all from a laboratory perspective. The results of this survey suggested that, to fabricate prostheses with a high level of predictability, functional utility, and aesthetic satisfaction, it is necessary to reaffirm the importance for dentists to increase their prosthetic knowledge and work together with dental technicians to develop comprehensive treatment plans, implement an organized approach to prosthesis design, and accomplish occlusal reconstruction.

Three-dimensional finite element analysis of the effects of implant diameter and photofunctionalization on peri-implant stress

Previous finite element analyses of peri-implant stress assumed a bone-implant contact (BIC) ratio of 100%, even though the BIC ratio is known to be approximately 50% or less. However, the recent development of ultraviolet treatment of titanium immediately before use, known as photofunctionalization, significantly increased the BIC ratio, to 98.2%. We used a unique finite element analysis model that enabled us to examine the effects of different BIC ratios on peri-implant stress. A three-dimensional model was constructed under conditions of vertical or oblique loading, an implant diameter of 3.3, 3.75, or 5.0 mm, and a BIC ratio of 53.0% or 98.2%. Photofunctionalization and larger implant diameters were associated with reduced stress on surrounding tissues. Under vertical loading, photofunctionalization had a greater effect than increased implant diameter on stress reduction. Under oblique loading, increased implant diameter had a greater effect than photofunctionalization on stress reduction.

Ossification of the anterior longitudinal ligament observed during upper endoscopy for dysphagia

Abstract The patient was a 78-year-old man with a chief complaint of dysphagia. Extrinsic displacement of the posterior hypopharyngeal wall was observed on upper endoscopy. The patient was diagnosed with ossification of the anterior longitudinal ligament (OALL) of the cervical spine according to lateral cervical spine radiographic findings. The OALL caused dysphagia. In swallowing endoscopic assessments of patients with dysphagia, OALL of the cervical spine should be differentiated from other possible diagnoses by using radiography when extrinsic displacement of the posterior oropharyngeal or hypopharyngeal wall is observed.

Diverse calcification patterns of ameloblastic fibro-odontoma on radiographic examination

The occurrence of ameloblastic fibro-odontoma (AFO) in the oral region is unusual and accounts for 1-3% of all odontogenic tumors. AFO presents mixed radiopaque patterns within the lesion with diverse findings; therefore, it is important to compare this tumor with other odontogenic tumors that radiographically present with calcified bodies. Herein, we observed the calcification patterns within the lesion in seven AFO cases (five males, two females; mean age, 8.3 years; age range, 4-13 years). Periapical and panoramic radiographs were obtained from all seven cases. Five cases underwent conventional computed tomography (CT) scanning, and one underwent cone beam CT. Classification of the calcifications primarily involved the following two characteristics on the X-rays: appearance and location of the lesions. All seven cases were located in the molar regions of the mandible in association with impacted teeth. The calcification patterns of these AFOs were mixed or inhomogeneous within the lesion with various findings, including complex odontoma-like calcifications. However, the patterns differed between panoramic radiography and CT in some cases. The radiolucent lesions in AFO demonstrated varying calcification patterns and were associated with impacted teeth on the CT images.(J Oral Sci 58, 533-537, 2016).

Relationship between growth of facial morphology and chronologic age in preschool children with obstructive sleep apnea.

BACKGROUND The purpose of this study was to evaluate the relationship between facial morphology using cephalometry and chronologic age in preschool children with obstructive sleep apnea (OSA). MATERIALS AND METHODS From a group of lateral cephalometric radiographs taken of 35 children with OSA for diagnostic purposes, 15 were selected for the present investigation based on head position. The subjects consisted of preschool children with both OSA and primary dentition, all of them with a lowest documented SpO(2) <90% and a lowest 0 <AI. The control group included 15 preschool children with primary dentition and without enlarged tonsils or adenoids. RESULTS The present findings reveal that, compared to the controls, OSA children had a narrower pharyngeal airway space related to OSA. In addition, we found that, although there were direct correlations between heights, nasal floor and corpus length, with chronologic age in the controls, there was no significant correlation between height, nasal floor length or corpus length with age in the OSA children. CONCLUSION Obstructive sleep apnea in children may be associated with growth disturbances of the nasal floor and corpus length.