A variety of shapes has been reported for the roots and root canals of maxillary first premolars. The purposes of the present study were to determine branching and shapes of the roots of maxillary first premolars, as well as age-related changes using slice images obtained with cone-beam computed tomography (CBCT) for dental use. CBCT-reconstructed images of 125 cases that included maxillary first premolars were used as subjects. Slice images at the cervical one-third, center, and apical one-third positions of the root were prepared. Root branching and number of root canals was determined at each measurement position in the images. The subjects were divided into three groups: younger than 30 years, 30 to 50 years, and over 50 years. The root canal morphology was compared among these age groups. Single-rooted premolars were the most frequent. As for number of root canals, a single-canal premolar was observed at the position of the cervical one-third in 33.6%, at the center in 35.2%, and at the apical one-third in 56.0%. Thereafter the subjects were divided into groups by age, namely, younger than 30 years, 30 to 50 years, and over 50 years old, and it was revealed that the ratio of the two-canal type increased with age. In regard to tooth morphology, it was confirmed that the two-canal type shows more frequent occurrence with aging in maxillary first premolar. Based on our findings, we consider that CBCT can be useful for determining the root canal morphology with complicated shapes.

AIMTo investigate the outcomes for Asian populations with locally advanced/clinical stage III prostate cancer (PCa) treated with currently prevailing modalities.

METHODSWe reviewed the record of 209 patients with clinical stage III PCa, who were treated at Niigata Cancer Center Hospital between 1992 and 2003. Treatment options included hormone therapy-combined radical prostatectomy (RP+HT), hormone therapy-combined external beam irradiation (EBRT+HT) and primary hormone therapy (PHT).

RESULTSThe 5- and 10-year overall survival rates were 80.3% and 46.1% in all cohorts, respectively. The survival rates were 87.3% and 66.5% in the RP+HT group, 94.9% and 70.0% in the EBRT+HT group and 66.1% and 17.2% in the PHT group, respectively. A significant survival advantage was found in the EBRT+HT group compared with that in the PHT group (P < 0.0001). Also, the RP+HT group had better survival than the PHT group (P = 0.0107). The 5- and 10-year disease-specific survival rates for all cases were 92.5% and 80.0%, respectively. They were 93.8% and 71.4% in the RP+HT group, 96.6% and 93.6% in the EBRT+HT group and 88.6% and 62.3% in the PHT group, respectively. A survival advantage was found in the EBRT+HT group compared with the PHT group (P = 0.029). No significant difference was found in disease-specific survival between the EBRT+HT and RP+HT groups or between the RP+HT and PHT groups.

CONCLUSIONAlthough our findings indicate that radiotherapy plus HT has a survival advantage in this stage of PCa, we recommend therapies that take into account the patients'social and medical conditions for Asian men with clinical stage III PCa.

Aged ; Follow-Up Studies ; Humans ; Japan ; Male ; Middle Aged ; Prostate-Specific Antigen ; blood ; Prostatectomy ; Prostatic Neoplasms ; drug therapy ; mortality ; pathology ; radiotherapy ; surgery ; Retrospective Studies ; Survival Rate ; Time Factors ; Treatment Outcome