Koichi Okabe

Factors affecting the occurrence of bacteremia associated with tooth extraction

This study examined the factors that affect the occurrence of bacteremia associated with tooth extraction and the kinds of bacteria causing this bacteremia. Bacteremia was found in 132 (72.1%) of 183 patients who had one or more teeth extracted for various reasons. Bacteremia occurred more frequently when teeth were extracted because of inflammatory dental diseases. The occurrence of bacteremia also increased with the number of teeth extracted and the age of the patients. When the volume of blood lost during surgery was > 50 ml and the time required for the operation exceeded 100 min, the occurrence of bacteremia was also higher. Anaerobes were isolated from 104 (78.8%) of the 132 cases of bacteremia. Of the 187 isolates obtained, three (1.6%) were aerobes, 51 (27.3%) were facultative anaerobes (including microaerophils), and 133 (71.1%) were anaerobes. Among facultative anaerobes and microaerophils, the most frequently isolated bacterial genera were Lactobacillus (n = 15), Streptococcus (n = 13), and Staphylococcus (n = 12); and among anaerobes, Eubacterium (n = 40), Peptostreptococcus (n = 40), and Propionibacterium (n = 20).

The effect of mandibular setback or two-jaws surgery on pharyngeal airway among different genders

Cephalometric studies show significant gender differences in the size of the pharyngeal airway space. This study aimed to investigate and compare morphologic changes after mandibular setback or two-jaws surgery on the pharyngeal airway in men and women using computed tomography (CT). The sample included 34 women and 13 men diagnosed with Class III skeletal deformities, who had been treated by mandibular setback or bimaxillary surgery (maxillary advancement and mandibular setback). Anteroposterior, lateral and cross-sectional area dimensions of the airway, at the level of soft palate and base of tongue, were measured pre- and postoperatively on CT images. In the mandibular setback group, the anteroposterior and cross-sectional area of the pharyngeal airway at the level of the soft palate and base of tongue were significantly reduced for men or women (P<.05). In the two-jaws surgery group, only midsagittal anteroposterior dimensions at the same levels were significantly decreased for men or women (P<.05). The difference between any values measured between men and women who received bilateral sagittal split ramus osteotomy setback surgery or two-jaws surgery for the treatment of class III anteroposterior discrepancy were not statistically significant (P>.05). This study suggests that oropharyngeal airway measurements, important for airway patency, do not demonstrate sex dimorphism.

Intraosseous lipoma of the maxilla: A case report

Abstract A case of intraosseous lipoma occurring in the maxilla of a 17-year-old boy is described.

Cystic Basal Cell Adenoma of the Parotid Gland with an Adenoid Cystic Carcinoma-like Structure

Abstract Basal cell adenoma is a rare disease that was introduced as an entity by the World Health Organization in 1991. Histologically, this tumour can be easily confused with basal cell adenocarcinoma and the solid basaloid subtype of adenoid cystic carcinoma. In this report, immunohistochemical methods were used for accurate diagnosis. No reaction for cytokeratin 10/13 was observed. The distribution of cytokeratin 14 was localised in the outer layer of the tubular patterns and the duct-like structures of the adenoid cystic carcinomalike nest. The reactions for cytokeratin 18 and cytokeratin 19 were positive in the inner layer of tubular patterns. The immunoreactivity for S-100 protein closely corresponded with that for cytokeratin 18. The reaction for Ki67 was slight positive. These findings indicate that histopathological and immunohistochemical analysis might be useful discrimination techniques for the diagnosis, treatment, and prognosis of parotid gland tumours.