下颌第三磨牙牙尖数与牙根数的关系研究

Relation between the cusps and roots of mandibular third molars

关键词:  下颌第三磨牙  牙根  牙尖  应用解剖

Key words:  mandibular third molar  dental root  dental cusp  clinical anatomy

摘要:

［目的］ 探讨下颌第三磨牙的牙尖数与牙根数的关系，为临床拔除阻生齿提供依据。［方法］ 记录210颗临床拔除的下颌第三磨牙的牙尖数和牙根数目,统计牙尖、牙根间的相关性。［结果］（1）下颌第三磨牙4尖型和5尖型多见，占79.53%；5尖型两根者多见，占56.86%，为本组临床最多见类型；（2）牙尖数增多时,其牙根的数目也增加，两者之间存在正相关关系。［结论］ 通过观察下颌第三磨牙的咬合面牙尖数目的多少,可间接推导该牙的牙根数目，有助于临床顺利拔除阻生牙。

Abstract:

［Objective］ This work is to study the relationship of mandibular third molars between the number of dental cusps and that of roots. ［Methods］ Two hundred and ten extracted mandibular third molars were collected. The number of cusps and roots was directly observed and analyzed. ［Results］(1)The mandibular third molars that had 4 or 5 cusps was 79.53% . The mandibular third molars which had 5 cusps and 2 roots was 56.86%.(2)The number of the dental roots may increase when the cusps increased.［Conclusion］ The number of the roots should be evaluated possibly before the mandibular third molars are extracted.