Gupta Jaya, Taneja Sonali, Jain Anshi
Department of Conservative Dentistry and Endodontics, I.T.S.-C.D.S.R, Ghaziabad, Uttar Pradesh, India.
Department of Oral Pathology, I.T.S.-C.D.S.R, Ghaziabad, Uttar Pradesh, India.
J Conserv Dent. 2021 Mar-Apr;24(2):214-218. doi: 10.4103/JCD.JCD_620_20. Epub 2021 Oct 9.
The objective of this study was to assess the effect of dental acid etchant (DAE)-mediated photodynamic therapy on bacterial reduction and microshear bond strength of composite to dentin.
Eighty permanent third molars after sample preparation were exposed to a cariogenic challenge with . After incubation, specimens were randomly divided into four groups ( = 20): Group I - DAE, Group II - low-level laser (LLL), Group III - diode laser + methylene blue (MB + L), and Group IV - diode laser + DAE (DAE + L). Half of the specimens from each group were selected for bacterial reduction assessment and the other half for microshear bond strength. All the samples for assessment of bacterial reduction (before and after intervention) were seeded onto the surface of mitis-salivarius-bacitracin medium. After incubation, the viable bacterial count was determined in colony-forming unit/mL. For microshear bond strength assessment, samples were subjected to various treatment modalities and then bonding and debonding procedure was performed for blocks of composite and values were recorded.
Significant reductions in were observed in all the groups - Group I (DAE) 68.50%, Group II (LLL) 55.90%, Group III (MB + L) 88.60%, and Group IV (DAE + L) 87% with comparable bacterial reduction between Group III (MB + L) and Group IV (DAE + L). Furthermore, a significant difference in bond strength values was seen in Group III (MB + L) 10.99 MPa and Group IV (DAE + L) 17.99 MPa whereas an insignificant difference was found between Group I (DAE) 20.74 MPa, Group II (LLL) 18.27 MPa, and Group IV (DAE + L).
DAE caused a comparable reduction in bacterial count to MB-assisted PDT and also there was no adverse effect on bond strength values. PDT can be performed while acid etchant containing MB dye is being applied in the cavity, thus reducing operative time and enhancing cavity disinfection.
本研究的目的是评估牙科酸蚀剂（DAE）介导的光动力疗法对复合树脂与牙本质之间细菌减少及微剪切粘结强度的影响。
80颗经过样本制备的恒牙在受到致龋挑战后，经过孵育，将标本随机分为四组（每组n = 20）：第一组 - DAE，第二组 - 低强度激光（LLL），第三组 - 二极管激光 + 亚甲蓝（MB + L），第四组 - 二极管激光 + DAE（DAE + L）。每组中一半标本用于细菌减少评估，另一半用于微剪切粘结强度评估。所有用于细菌减少评估（干预前后）的样本接种到轻唾杆菌 - 杆菌肽培养基表面。孵育后，以菌落形成单位/毫升确定活菌计数。对于微剪切粘结强度评估，样本接受各种处理方式，然后对复合树脂块进行粘结和脱粘程序，并记录数值。
所有组的细菌数量均显著减少 - 第一组（DAE）为68.50%，第二组（LLL）为55.90%，第三组（MB + L）为88.60%，第四组（DAE + L）为87%，第三组（MB + L）和第四组（DAE + L）的细菌减少情况相当。此外，第三组（MB + L）的粘结强度值为10.99 MPa，第四组（DAE + L）为17.99 MPa，二者存在显著差异，而第一组（DAE）为20.74 MPa、第二组（LLL）为18.27 MPa与第四组（DAE + L）之间无显著差异。
DAE导致的细菌数量减少与MB辅助的光动力疗法相当，并且对粘结强度值没有不良影响。在窝洞内应用含MB染料的酸蚀剂时可进行光动力疗法，从而减少手术时间并增强窝洞消毒。
