Jokstad A, Mjör I A
Department of Anatomy, School of Dentistry, University of Oslo, Norway.
Acta Odontol Scand. 1991 Feb;49(1):47-63. doi: 10.3109/00016359109041140.
The purpose of the study was to estimate the influence of different clinical variables on the replacement rate of class-II amalgam restorations in permanent teeth. The study included 210 patients who had 468 restorations placed by 7 Scandinavian dentists. The observation periods varied between 7 and 10 years. At the time of the last recording 188 restorations remained intact in 88 patients, whereas 68 restorations in 53 patients had been replaced. Eighty-six patients with 212 restorations had dropped out of the study. The most prevalent criteria for replacement were secondary caries (n = 30) and restoration bulk fractures (n = 24). Chi-square analyses of the relationship between the prevalence of replacements and the clinical variables indicated effects of the operator and the patients' age and caries activity (p less than 0.001). Similar results were observed when the functional time of the restorations was related to the clinical variables and analyzed by ANOVA and MCA analyses and by survival analyses using logrank and Wilcoxon tests (p less than 0.001). The survival analyses using the Lee-Desu statistic D showed in addition a slight difference between the restorations in the lower premolars and upper and lower molars. There were no differences in the clinical performance between four non-gamma-2 alloys and one conventional alloy. Furthermore, no differences were noted between the survival rates of MC, DO, and MOD restorations. In a Cox regression model the strongest effects on the estimated survival rates were associated with the patients' age and caries activity covariates (global chi-square = 23.5, df = 2, p less than 0.001), whereas the effects of the operator and the other clinical variables were insignificant.
本研究的目的是评估不同临床变量对恒牙Ⅱ类银汞合金修复体替换率的影响。该研究纳入了210例患者，这些患者有468颗修复体由7位斯堪的纳维亚牙医进行放置。观察期在7至10年之间。在最后一次记录时，88例患者中的188颗修复体保持完好，而53例患者中的68颗修复体已被替换。86例患者的212颗修复体退出了研究。最常见的替换标准是继发龋（n = 30）和修复体大块折断（n = 24）。对替换发生率与临床变量之间关系进行的卡方分析表明，操作者、患者年龄和龋病活动有影响（p < 0.001）。当修复体的功能时间与临床变量相关，并通过方差分析、多因素分析以及使用对数秩和威尔科克森检验的生存分析进行分析时，观察到了类似结果（p < 0.001）。使用Lee-Desu统计量D进行的生存分析还显示，下颌前磨牙与上颌及下颌磨牙的修复体之间存在细微差异。四种非γ-2合金与一种传统合金在临床性能上没有差异。此外，MC、DO和MOD修复体的生存率之间没有差异。在Cox回归模型中，对估计生存率影响最大的是患者年龄和龋病活动协变量（全局卡方 = 23.5，自由度 = 2，p < 0.001），而操作者和其他临床变量的影响不显著。
