无髓牙牙根纵裂原因分析

目的探讨无髓牙牙根纵裂发生的原因并提出相应的预防措施。方法收集17例共20颗发生牙根纵裂无髓牙的临床诊治资料。回顾治疗前患牙的牙体和牙周的状况,观察和分析治疗和修复后患牙牙根折裂发生的部位、折裂方向、修复体的类型、患牙在修复体的位置及其咬情况。结果本组无髓牙牙根纵裂以后牙多见(16/20);牙冠完整者发生牙根纵裂多见于前牙(4/20)和前磨牙(5/20);19例有不同程度的牙槽嵴高度的降低(轻度8例,中度7例,重度4例)。冠修复后牙根纵裂者主要发生于磨牙(6/7);作为固定或活动修复体的基牙均可能发生牙根纵裂;咬关系观察分析显示,本组7例存在早接触,其中6例为侧向早接触,1例为正中早接触,提示前者更易造成牙根纵裂。结论无髓牙牙根纵裂的病因复杂。由于预后不佳,牙根纵裂应以预防为主。

Clinical investigation of causes of vertical root fracture in pulpless teeth

Objective To investigate the cause of vertical root fracture in pulpless teeth, and advance the measures of prevention. Methods The clinical data of 20 vertical root fracture in pulpless teeth (17 patients) were collected. The status of the teeth and periodontium before therapy were reviewed, the position and direction of the root fracture were observed, the type and position of the restoration and the occludent station of the teeth were analyzed. Results It was revealed that vertical root fracture frequently occurred in the molars (16/20). Vertical root fracture were frequently found in front teeth(4/20) and premolars (5/20)among those with coronal integrity. Decrease of alveolar level of various degrees was found in 19 cases, among which 8 were mild, 7 moderate and 4 severe. Vertical root fracture mainly took place in molars after coronal restoration (6/7). Vertical root fracture would likely to occur no matter whether they would be worked as the abutment teeth of the removable partial denture or fixed prostheses. Early contact occurred in lateral bite (6 cases) was more susceptible to vertical root fracture than that occurred in centric bite (1 case). Conclusion The causes of vertical root fracture in pulpless teeth are complicated. Due to unfavorable outcomes, it is important to take precautions for vertical root fracture.