小管密度和固体牙本质面积对两种粘结系统与牙本质粘结强度的影响。

The influence of tubule density and area of solid dentin on bond strength of two adhesive systems to dentin.

作者信息

Giannini M, Carvalho R M, Martins L R, Dias C T, Pashley D H

机构信息

Department of Restorative Dentistry, Piracicaba School of Dentistry, University of Campinas, SP, Brazil.

出版信息

J Adhes Dent. 2001 Winter;3(4):315-24.

PMID:11893047

Abstract

PURPOSE

To determine the correlation between the tubule density (TD) and the area occupied by solid dentin (ASD) with the bond strength of one conventional and one self-etching adhesive system to dentin.

MATERIALS AND METHODS

The crown of extracted human third molars was transversally sectioned with a diamond saw to expose either superficial, middle, or deep dentin. The three groups of dentin surfaces were randomly divided and bonded with either Clearfil Liner Bond 2V (LB) or Prime & Bond 2.1 (PB) adhesive systems according to manufacturer's directions. Resin composite buildup crowns (10.0 mm high) were incrementally constructed on the bonded surfaces and the teeth stored in water at 37 degrees C. After 24 h of storage, the teeth were vertically, serially sectioned in both x and y directions to obtain several bonded sticks of approximately 0.7 mm2 cross-sectional area. Each stick was tested in tension in a EMIC DL-500 tester at 0.5 mm/min until failure. After testing, the dentin side of the fractured specimen was gently abraded with a 1000-grit SiC paper, etched with 37% phosphoric acid for 15 s and allowed to air dry. SEM micrographs at 1000x and 4000x magnification were taken to permit calculation of the TD (number of tubules/mm2) and ASD (% of total area) at the site of fracture. Correlation between TD and ASD with the bond strength data was performed by linear regression. All statistical analysis was done with alpha = 0.05.

RESULTS

Overall bond strength (MPa) for LB was 26.0 +/- 10.2, and 42.6 +/- 15.2 for PB. There was a significant direct relationship between bond strength and ASD for both materials (r2 = 0.20, p < 0.05 and r2 = 0.66, p < 0.01, respectively for LB and PB). PB bond strength dropped significantly as the TD increased (r2 = 0.63, p < 0.05), while LB was not sensitive to TD (r2 = 0.05, p > 0.05). Mean bond strength of PB was significantly higher than LB for both superficial and middle dentin (p < 0.05), while there was no significant difference for deep dentin (p > 0.05).

CONCLUSION

Regional variations in TD and ASD may modify bond strength of both conventional and self-etching adhesive systems. Bonding sites with larger ASD seem to yield higher bond strengths regardless of the type of adhesive system used.

摘要

目的

确定小管密度（TD）和固体牙本质所占面积（ASD）与一种传统和一种自酸蚀粘结系统与牙本质粘结强度之间的相关性。

材料与方法

用金刚石锯将拔除的人类第三磨牙牙冠横向切开，以暴露表层、中层或深层牙本质。将三组牙本质表面随机分组，并按照制造商的说明分别用Clearfil Liner Bond 2V（LB）或Prime & Bond 2.1（PB）粘结系统进行粘结。在粘结表面逐步构建树脂复合材料修复冠（高10.0 mm），并将牙齿储存在37℃的水中。储存24小时后，将牙齿在x和y方向上垂直连续切片，以获得若干横截面积约为0.7 mm²的粘结条。每个粘结条在EMIC DL - 500测试仪中以0.5 mm/min的速度进行拉伸测试，直至破坏。测试后，将断裂试样的牙本质侧用1000目碳化硅砂纸轻轻打磨，用37%磷酸蚀刻15秒，然后风干。拍摄放大1000倍和4000倍的扫描电子显微镜照片，以计算断裂部位的TD（小管数/mm²）和ASD（占总面积的百分比）。通过线性回归分析TD和ASD与粘结强度数据之间的相关性。所有统计分析的α = 0.05。

结果

LB的总体粘结强度（MPa）为26.0±10.2，PB为42.6±15.2。两种材料的粘结强度与ASD之间均存在显著的正相关关系（LB和PB的r²分别为0.20，p < 0.05和r²为0.66，p < 0.01）。随着TD增加，PB的粘结强度显著下降（r² = 0.63，p < 0.05），而LB对TD不敏感（r² = 0.05，p > 0.05）。对于表层和中层牙本质，PB的平均粘结强度显著高于LB（p < 0.05），而对于深层牙本质则无显著差异（p > 0.05）。