Velásquez Humberto, Olate Sergio, Díaz César, Navarro Pablo, Borie Eduardo, de Moraes Márcio
1 Dental Sciences Program, Dental School, Universidad de La Frontera, Temuco, Chile.
2 Division of Oral and Maxillofacial Surgery & Center for Morphological and Surgical Studies, Universidad de La Frontera, Temuco, Chile.
J Oral Implantol. 2017 Jun;43(3):211-217. doi: 10.1563/aaid-joi-D-16-00150. Epub 2017 Mar 13.
The aim of this study was to quantify the cortical and cancellous bone in the mandibular symphysis and relate it to the teeth and to the skeletal class. A descriptive study was conducted using cone beam computerized tomography (CBCT). Class I and class III subjects were included, defined according to dental occlusion and cephalogram results. Linear measurements were taken on the CBCT of the mandibular canines, lateral incisors, and central incisors, where the analysis was related to the axial and apical axes considering the bone in relation to the dental area. With previous definitions, an observer took 2 measurements of the height of the mandibular symphysis, cortical bone of the buccal and lower region, and thickness of cancellous bone at different levels; the correlation coefficient between the first and second measurement was 0.99 and presented P = .001. The results were analyzed with analysis of variance and Tukey's honest significant difference test, with P < .05 being statistically significant. The symphysis height was significantly greater in class III subjects. The cortical bone was an average 1.67 ± 0.44 mm in vertical distance in the skeletal class I group and 1.74 ± 0.47 mm in the class III group. The cancellous bone had an average width of 5.03 ± 1.94 mm in the skeletal class I group and 4.74 ± 2.05 mm in the class III group. It was observed that cancellous bone was significantly thicker at the incisor level than at the canine level. There were anatomical differences between skeletal class I and class III subjects, although the clinical significance may be questionable. With the values from these analyses, it may be concluded that there are no significant differences in quantitation of the cortical and cancellous bone in the anterior mandibular symphysis.
本研究的目的是量化下颌骨联合处的皮质骨和松质骨，并将其与牙齿及骨骼类型相关联。采用锥形束计算机断层扫描（CBCT）进行了一项描述性研究。纳入了根据牙合关系和头颅侧位片结果定义的I类和III类受试者。在下颌尖牙、侧切牙和中切牙的CBCT上进行线性测量，分析时考虑与牙区相关的骨组织，涉及轴向和根尖轴。根据先前的定义，一名观察者对下颌骨联合处的高度、颊侧和下部区域的皮质骨以及不同水平的松质骨厚度进行了两次测量；第一次和第二次测量之间的相关系数为0.99，P值为0.001。结果采用方差分析和Tukey诚实显著差异检验进行分析，P < 0.05具有统计学意义。III类受试者的下颌骨联合处高度显著更高。I类骨骼组的皮质骨垂直距离平均为1.67±0.44 mm，III类组为1.74±0.47 mm。I类骨骼组的松质骨平均宽度为5.03±1.94 mm，III类组为4.74±2.05 mm。观察到松质骨在切牙水平比尖牙水平明显更厚。I类和III类骨骼受试者之间存在解剖学差异，尽管其临床意义可能存疑。根据这些分析结果，可以得出结论，下颌前部联合处皮质骨和松质骨的量化没有显著差异。
