固定修复基牙邻面龋坏治疗洞型设计的探讨

In vitro study on the design of the caries cavity forms on the proximal surface of abutment teeth for fixed prosthesis

目的 探讨增加固定修复基牙强度、较少磨除基牙组织的洞型设计。方法 收集完整的离体上下颌第一、二磨牙 1 80颗 ,分为 9组 ,每组 2 0颗。Ⅰ组为对照组 (完整牙 ) ,Ⅱ～Ⅸ组分别制备具有临床代表意义的洞型。常规充填后 ,分别进行抗折负荷测试。结果 抗折负荷邻颈洞型较邻颈牙合浅洞型大 2 4 2 % ,邻颈、牙合洞型较邻颈牙合深洞型大 5 0 8% ,邻面洞型较邻牙合浅洞型大 9 8% ,邻、牙合洞型较邻牙合深洞型大 2 1 % ,邻牙合深洞型较邻颈牙合深洞型大 2 4 9%。结论 对基牙邻面龋坏 ,特别是邻面颈部龋坏 ,争取就自然洞型完成充填 ,能显著增加其抗折强度 ;必须经牙合面行根管治疗时 ,邻牙合面分开洞型 ,能明显增加抗折负荷。

ObjectiveTo study the cavity form design in o rder to lessen grinding and to enhance the strength of abutment teeth with carie s for fixed prosthesis.MethodsOne hundred and eighty extracted intact teeth(First and Second molars)were collected and divided into 9 groups with 20 in each. Var ious cavity forms were prepared on the proximal and occlusal surface of the teet h representing clinical meanings in group ~{'r*2'y~}. All teeth were tested for anti fracture loading after routine filling. The teeth in group ~{'q~} were control. ResultsThe antifracture loading value(~{*+~}n,~{!<~}AKx-D~{!=!@~}s~{*+~}) o f the control teeth was 4264.17~{!@~}565.19, that of the teeth with proximal cavity 3862.24~{!@~}523. 18, with proximal cervical cavity 3795.36~{!@~}541.25, with shallow proximalocclus al cavity 3516.50~{!@*)~}590.25~{**~}, with shallow proximalcervicalocclusal cavity 3056 .21~{!@~}545.32, with deep proximalocclusal cavity 1903.38~{!@~}681.36, with proximal and occlusal cavity 2305.58~{!@~}549.56, with deep proximalcervicalocclusal cavi ty 1524.15~{!@~}549.21 and with proximal cervical and occlusal cavity ~{*)~}2298.89~{**!@~}4 98.57, respectively.ConclusionFilling of the cavities on the proximal surface in t he original forms of caries, especially in cervical area, may be feasible for an tifracture strength of the abutment teeth for fixed dental prosthesis. If root canal treatment through occlusal surface is necessary, separate filling of cavi ties on both proximal and occlusal surface is also a choice to increase the stre ngth of abutment teeth.