Sorel O, el Alam R, Chagneau F, Cathelineau G
Laboratoire de Biomatériaux en site osseux, Université de Rennes I.
Orthod Fr. 2000 Apr;71(2):155-63.
The aim of this study was to assess the incidence on the enamel behavior of debonding two types of orthodontic brackets, bonded with two different adhesives. Ninety recently extracted human premolars were bonded with two types of brackets (30 Minitrim and 60 Discovery). Two bonding protocols were used. The first one consisted in bonding 30 Minitrim and 30 Discovery brackets on etched and dried enamel surfaces with No Mix orthodontic resin. The second one consisted in bonding 30 Discovery brackets on unetched and wet enamel surfaces with a modified glass ionomer cement, Fuji Ortho LC. Teeth were stored in hydrated ambiance at 37 degrees C for 7 days before debonding. A LLOYD (LR 30K) testing machine was used to evaluate the orthogonal tensile bond strength. The debonded base brackets were examined with a scanning electron microscope (JEOL JSM 6400) and qualitatively analyzed with an OXFORD-LINK-ISIS to assess the site of bond failure and the enamel detachments. An Enamel Detachment Index (EDI) was defined. The results showed that the types of orthodontics brackets and adhesives influenced the bond strength and the enamel detachment. The Discovery/No Mix couple presented higher bond strength (214.9 N) than observed with the Discovery/Fuji Ortho LC (98.5 N) or the Minitrim/No Mix (82.3 N) couples. The surfaces of enamel detachment were insignificant and not extended for all brackets. Nevertheless, the Discovery/No Mix couple presented 42% of an EDI score of 1, compared to the Discovery/Fuji Ortho LC and Minitrim/No Mix couples which presented, respectively, 8% an 20% of an EDI score of 1. The laser sculpted base (Discovery) bonded on unetched and wet enamel surfaces with the modified glass ionomer cement (Fuji Ortho LC) offers a good resistance to debonding forces and preserve enamel integrity.
本研究的目的是评估用两种不同粘合剂粘结的两种正畸托槽脱粘时对牙釉质行为的影响。九十颗近期拔除的人类前磨牙用两种托槽（30颗Minitrim和60颗Discovery）进行粘结。采用了两种粘结方案。第一种方案是用No Mix正畸树脂在酸蚀和干燥的牙釉质表面粘结30颗Minitrim和30颗Discovery托槽。第二种方案是用改良玻璃离子水门汀Fuji Ortho LC在未酸蚀和湿润的牙釉质表面粘结30颗Discovery托槽。在脱粘前，将牙齿在37℃的湿润环境中保存7天。使用LLOYD（LR 30K）试验机评估正交拉伸粘结强度。用扫描电子显微镜（JEOL JSM 6400）检查脱粘后的托槽基部，并使用OXFORD-LINK-ISIS进行定性分析，以评估粘结失败的部位和牙釉质脱落情况。定义了牙釉质脱落指数（EDI）。结果表明，正畸托槽和粘合剂的类型会影响粘结强度和牙釉质脱落情况。Discovery/No Mix组合的粘结强度（214.9 N）高于Discovery/Fuji Ortho LC（98.5 N）或Minitrim/No Mix（82.3 N）组合。对于所有托槽，牙釉质脱落的表面不明显且范围未扩展。然而，Discovery/No Mix组合有42%的EDI评分为1，而Discovery/Fuji Ortho LC和Minitrim/No Mix组合分别有8%和20%的EDI评分为1。用改良玻璃离子水门汀（Fuji Ortho LC）粘结在未酸蚀和湿润牙釉质表面的激光雕刻基部（Discovery）对脱粘力具有良好的抵抗力，并能保持牙釉质的完整性。
