Eakle W S, Maxwell E H, Braly B V
J Am Dent Assoc. 1986 Feb;112(2):215-8. doi: 10.14219/jada.archive.1986.0344.
Examined in this study were 191 patients with 206 complete or incomplete fractures of posterior teeth. The patients ranged in age from 14 to 76 years, with 66.5% younger than 40 years. The number of fractures occurring in each arch was almost equal. The mandibular first molar was the most frequently fractured posterior tooth. The lingual cusps of mandibular molars fractured more often than did the buccal cusps of mandibular molars by a ratio of 2 to 1. In maxillary molars, buccal and lingual cusps fractured with almost equal frequency, but, in maxillary premolars, the lingual cusps fractured slightly more often than buccal cusps. Data gathered on the widths of the isthmuses of restorations in 109 teeth showed that fewer fractures occurred in teeth with more conservative restorations, with widths of isthmuses a quarter of the inter-cusp distance, and intact marginal ridges.
本研究检查了191例患者的206颗后牙完整或不完整骨折。患者年龄在14至76岁之间，66.5%的患者年龄小于40岁。每个牙弓发生骨折的数量几乎相等。下颌第一磨牙是最常发生骨折的后牙。下颌磨牙的舌尖骨折比颊尖骨折更常见，比例为2比1。在上颌磨牙中，颊尖和舌尖骨折的频率几乎相等，但在上颌前磨牙中，舌尖骨折比颊尖略多。在109颗牙齿上收集的修复体峡部宽度数据表明，峡部宽度为牙尖间距离四分之一且边缘嵴完整的更保守修复的牙齿骨折较少。
