RESUMEN
Background@#The primary objectives of mandibular surgery are to achieve optimal occlusion, low sensory disturbance, and adequate fixation with early movement. In-depth knowledge of the mandibular structure is required to achieve these goals. This study used computed tomography (CT) to evaluate the mandibular cortical thickness and cancellous space according to age and sex. @*Methods@#We enrolled 230 consecutive patients, aged 20 to 50 years, who underwent CT scanning. The cortex and cancellous space centered around the inferior alveolar nerve (IAN) canal were measured at two specific locations: the lingula and second molar region. Statistical analysis of differences according to increasing age and sex was performed. @*Results@#The t-test revealed that the cancellous space and cortical thickness differed significantly with respect to the threshold of 35 years of age. Both cortical thickness and cancellous space in the molar region were negatively correlated with age. Meanwhile, both cortical thickness and cancellous space in the lingula region showed a positive correlation with age. With respect to sex, significant differences in the cancellous space at the molar region and the cortical thickness at the lingula were observed. However, no further statistically significant differences were observed in other variables with respect to sex. The sum of each measurement on the mandibular body reflected the safe distance from the surface of the outer cortex to the IAN canal. The safe distances also showed statistically significant differences between those above and below 35 years of age. @*Conclusion@#Knowledge of the anatomical structure of the mandible and of changes in bone structure is crucial to ensure optimal surgical outcomes and avoid damage to the IAN. CT examination is useful to identify changes in the bone structure, and these should be taken into account in the planning of surgery for older patients.
RESUMEN
BACKGROUND: The purpose of this study was to compare postoperative morbidities and functional outcomes of pectoralis major myocutaneous (PMMC) flap and cutaneous free flap reconstruction approaches in hypopharyngeal squamous cell carcinoma patients. METHODS: We retrospectively reviewed records from 99 patients who underwent hypopharyngeal reconstruction with a cutaneous free flap (n=85) or PMMC flap (n=14) between 1995 and 2013. Morbidity was classified into hospitalization, medical, or flap-related complications. Functional outcomes were classified into oral re-alimentation and decannulation time. RESULTS: The overall flap-related complication rate was higher in the PMMC flap group (n=8, 57.1%; P=0.019), but the medical morbidity rate was higher in the cutaneous free flap group (n=68, 80%; P=0.006). The rate of pneumonia was higher in the cutaneous free flap group (n=48, 56.5%; P=0.020). Pulmonary premorbidity was the variable most significantly associated with pneumonia (odds ratio=3.012, P=0.012). There was no statistically significant difference in oral re-alimentation and decannulation time between the two groups. CONCLUSIONS: Although the functional superiority of free flaps has been reported in many studies, our results do not support this hypothesis. One limitation of our study is the relatively smaller flap size and fewer PMMC flap cases compared with the cutaneous free flap group. The low postoperative medical morbidity incidence rate in the PMMC flap group was clinically significant; however, the free flap group had more flap-related complications. Thus, PMMC flaps should be considered a viable option, especially for patients with pulmonary premorbidities.