Cloyd S, Gilpatrick R O, Moore D
Department of General Dentistry, U.T., Memphis, USA.
J Tenn Dent Assoc. 1997 Oct;77(4):36-40.
A three-year clinical study was completed at the College of Dentistry comparing the overall performance of Class I amalgam restorations with preventive resin restorations (PRRs). Seventy-four PRRs and fifty-two amalgam restorations were placed in the posterior teeth of thirty-eight patients. The PRR was composed of two materials: P-50 (3M Corp.), a heavily filled composite resin, and White Sealant (3M Corp.), a light-cured sealant. Fast-set Dispersalloy (Johnson and Johnson Corp.) was used for the amalgam restorations. The restorations were evaluated at six months, one year, two years and three years. The USPHS/Ryge system was used to evaluate anatomic form, marginal adaptation, marginal discoloration and recurrent caries of both type restorations. A restoration was considered a failure if any part of the restoration was replaced due to secondary caries. There were two failures of PRRs at six months, and four failures at one year. Failures were due to non retention of the sealant of the PRR and possibly related to operator error. The failures were easily repaired and removed from the study. No PRR failed at the two or three year evaluations. No amalgam restoration failed within the three year period.
牙科学院完成了一项为期三年的临床研究，比较I类银汞合金修复体与预防性树脂修复体（PRR）的整体性能。在38名患者的后牙中放置了74个PRR和52个银汞合金修复体。PRR由两种材料组成：P-50（3M公司），一种高填料复合树脂，以及白色封闭剂（3M公司），一种光固化封闭剂。快速固化Dispersalloy（强生公司）用于银汞合金修复体。在6个月、1年、2年和3年时对修复体进行评估。采用USPHS/Ryge系统评估两种类型修复体的解剖形态、边缘适应性、边缘变色和继发龋。如果修复体的任何部分因继发龋而被替换，则该修复体被视为失败。PRR在6个月时有2例失败，1年时有4例失败。失败原因是PRR的封闭剂未保留，可能与操作人员失误有关。这些失败很容易修复并从研究中剔除。在两年或三年的评估中，没有PRR失败。在三年期间，没有银汞合金修复体失败。
