Clark Wendy Auclair, Hsu Yung-Tsung
Private Practice, Goldstein, Garber, & Salama LLC, Atlanta, GA.
J Prosthodont. 2014 Oct;23(7):528-33. doi: 10.1111/jopr.12156. Epub 2014 May 28.
This study analyzed the conventional method of rebonding a denture tooth, evaluating the effect of varied thickness of autopolymerizing acrylic resin on the bond strength and the failure mode.
A total of 52 heat-polymerizing acrylic resin specimens were fabricated with an anterior denture tooth. A cantilever-type bending force was applied with a universal testing machine to each specimen until failure. The failure mode was determined, and cohesive failures were excluded from part II. Thirty specimens were randomly selected and divided into three groups (n = 10). For each group, resin was relieved from the bonding area to create a 0, 1, or 3 mm space. The tooth was repositioned using its matrix and reattached to its base, filling the relieved space with autopolymerizing acrylic resin. The repaired specimens were tested using the same parameters. Data were analyzed with paired t-tests, one-way ANOVA, and post hoc test. Statistical significance was determined at p < 0.05.
The mean peak load to failure for the part I group was 88.91 N. While the peak load to failure decreased to 71.96 N (19.69% loss of original bond strength), statistical analysis revealed no difference between the bond strength of the specimens repaired with a 0 mm thickness of autopolymerizing acrylic resin and the original (part I) group (p > 0.05). The bond strength was lower for the group repaired with a 1 mm thickness compared to the original (part I) group (p < 0.05), with 65.8 N load to failure (29.63% loss). The bond strength was even lower for the group repaired with a 3 mm thickness (p < 0.05), with 58.64 N load to failure (33.07% loss). Post hoc analysis revealed a significant difference between the 0 and 3 mm groups (p = 0.04). The most common failure mode in the original group was adhesive (56%), then combination (34%), then cohesive (9.8%). The repaired group (n = 30) had similar results, with 56.7% adhesive, 36.7% combination, and 6.7% cohesive failures.
The bond strength of a replaced denture tooth is affected by the thickness of the autopolymerizing acrylic resin. The failure mode of a rebonded denture tooth follows the same trend of the original failure. If possible, replace teeth with no relief. If combination failure occurs, leave residual base acrylic resin on the ridge lap.
本研究分析了义齿牙齿重新粘结的传统方法，评估了自凝丙烯酸树脂不同厚度对粘结强度和失败模式的影响。
用一颗前牙义齿制作了52个热凝丙烯酸树脂标本。用万能试验机对每个标本施加悬臂式弯曲力直至失败。确定失败模式，在第二部分中排除内聚破坏。随机选择30个标本，分为三组（n = 10）。对于每组，从粘结区域去除树脂以形成0、1或3毫米的间隙。使用其模型重新定位牙齿，并将其重新附着于其基托，用自凝丙烯酸树脂填充去除树脂的间隙。使用相同参数对修复后的标本进行测试。数据采用配对t检验、单因素方差分析和事后检验进行分析。以p < 0.05确定统计学显著性。
第一部分组的平均破坏峰值载荷为88.91 N。虽然破坏峰值载荷降至71.96 N（原始粘结强度损失19.69%），但统计分析显示，用0毫米厚的自凝丙烯酸树脂修复的标本与原始（第一部分）组的粘结强度之间没有差异（p > 0.05）。与原始（第一部分）组相比，用1毫米厚树脂修复的组的粘结强度较低（p < 0.05），破坏载荷为65.8 N（损失29.63%）。用3毫米厚树脂修复的组的粘结强度更低（p < 0.05），破坏载荷为58.64 N（损失33.07%）。事后分析显示0毫米和3毫米组之间存在显著差异（p = 0.04）。原始组中最常见的失败模式是粘结性（56%），然后是混合性（34%），然后是内聚性（9.8%）。修复组（n = 30）有类似结果，粘结性失败占56.7%，混合性失败占36.7%，内聚性失败占6.7%。
替换义齿牙齿的粘结强度受自凝丙烯酸树脂厚度的影响。重新粘结义齿牙齿的失败模式与原始失败模式遵循相同趋势。如果可能，不做间隙替换牙齿。如果发生混合性失败，在牙槽嵴搭接处保留残留的基托丙烯酸树脂。
