Camargo Carlos H R, Siviero Mariana, Camargo Samira E Afonso, de Oliveira Simone H G, Carvalho Cláudio A T, Valera Márcia C
São José dos Campos, Faculty of Dentistry, São Paulo State University-UNESP, Av. Fco. José Longo 777, 12245-000 São Paulo, SP, Brazil.
J Endod. 2007 Apr;33(4):422-6. doi: 10.1016/j.joen.2006.12.011. Epub 2007 Feb 20.
The aim of this study was to evaluate the number and the diameter of dentin tubules in root canals, in the cervical, middle, and apical thirds, of human and bovine teeth. Twenty-four single-rooted, human premolars were divided into four groups (n = 6): GH1, 10 to 15 years; GH2, 16 to 30 years; GH3, 31 to 45 years; and GH4, 46 to 80 years; and 24 bovine incisors were divided into four groups (n = 6): GB1, central; GB2, lateral first; GB3, lateral second; and GB4, lateral third. The crowns were removed from the specimens, which were then debrided, sectioned longitudinally in the vestibular-lingual direction, and submitted to ultrasonic cleaning. Scanning electron microscopic evaluations were made with 1,000x and 5,000x magnification. According to the root thirds, statistically significant differences were found both for the number and the diameter of dentin tubules, with the cervical third presenting the highest mean values for both specimen types. As regards the number of dentin tubules, it was observed that the bovine specimens presented a significantly higher mean value than the human specimens; this difference was not observed when the diameters of the two types were compared.
本研究的目的是评估人牙和牛牙根管中颈段、中段和根尖段牙本质小管的数量和直径。24颗人单根前磨牙被分为四组（n = 6）：GH1组，10至15岁；GH2组，16至30岁；GH3组，31至45岁；GH4组，46至80岁；24颗牛切牙被分为四组（n = 6）：GB1组，中央；GB2组，第一侧切；GB3组，第二侧切；GB4组，第三侧切。从标本上移除牙冠，然后进行清创，沿前庭-舌侧方向纵向切片，并进行超声清洗。使用1000倍和5000倍放大倍数进行扫描电子显微镜评估。根据牙根各段，发现牙本质小管的数量和直径均存在统计学上的显著差异，两种标本类型的颈段牙本质小管数量和直径的平均值均最高。关于牙本质小管的数量，观察到牛标本的平均值显著高于人标本；比较两种类型的牙本质小管直径时未观察到这种差异。
