Haritha J, Rao M Reddi Narasimha, Padmaja B Indira, Reddy N Raja, Babu N Suresh, Karthik K V Guru Charan
Department of Prosthodontics Crown and Bridge, Proddatur, Kadapa, India.
Department of Prosthodontics Crown and Bridge and Implantology, C.K.S. Theja Institute of Dental Sciences and Research, Tirupathi, Andhra Pradesh, India.
J Family Med Prim Care. 2020 Mar 26;9(3):1640-1646. doi: 10.4103/jfmpc.jfmpc_939_19. eCollection 2020 Mar.
The aim of the present study was to compare and evaluate the retention of dislodged crowns by addition of one horizontal circumferential groove (HCG) to preparation and/or casting and with two luting cements.
A total of 80 recently extracted human maxillary first molar teeth of appropriate sizes were collected and mounted in the resin blocks using surveyor. Standardized full coverage tooth preparations were prepared and impressions were obtained. Dies were prepared for casting and were then subjected to tensile loading using UTM. The data obtained was statistically analyzed.
Obtained values were statistically analyzed using ANOVA, STUDENT "t" TEST and BONFERRONI TEST. The results showed that the mean tensile force (TF) was in the range from 49.05 to 264.87 for group A and 255.06 to 588.60 for group B. The highest TF was recorded for subgroup 3B, whereas the lowest for subgroup 1A.
Within the limitations of the study, it was concluded that by addition of one HCG to tooth preparation or casting and to both showed significant increase in retention, when compared to control groups. The highest retention value was obtained for sample with groove on the internal surface of crown luted with SARC.
本研究的目的是比较和评估通过在预备体和/或铸造过程中添加一条水平圆周沟(HCG)以及使用两种粘结水门汀来提高脱位牙冠的固位力。
总共收集80颗近期拔除的大小合适的人类上颌第一磨牙,使用测绘仪将其固定在树脂块中。制备标准化的全冠牙体预备体并制取印模。制作铸型用的代型,然后使用万能材料试验机对其进行拉伸加载。对获得的数据进行统计学分析。
使用方差分析、学生“t”检验和邦费罗尼检验对获得的值进行统计学分析。结果显示,A组的平均拉伸力(TF)在49.05至264.87之间,B组在255.06至588.60之间。3B亚组的TF最高,而1A亚组最低。
在本研究的局限性范围内,得出的结论是,与对照组相比,在牙体预备或铸造过程中添加一条HCG以及在两者中都添加,均显示固位力显著增加。使用SARC粘结的牙冠内表面有沟的样本获得了最高的固位值。