Outcome Evaluation of Non Carious Cervical Lesions restored using Dental Composite Resin with Glycolic Acid and Phosphoric Acid as Etchants A Double-Blind Split-Mouth Randomized Controlled Trial

This study titled Outcome Evaluation of Non Carious Cervical Lesions restored using Dental Composite Resin with Glycolic Acid and Phosphoric Acid as Etchants A Double Blind Split Mouth Randomized Controlled Trial is going to assess and compare the clinical outcome of non-carious cervical lesion restorations using dental composite resin with glycolic acid and phosphoric acid as etchants. A total of 170 restorations will be done and each participant will receive composite restorations on both sides of the mouth, with one side using glycolic acid and the other using phosphoric acid as the etchant.

For the split mouth trial the two treatment groups are randomly assigned to the right or left side using a block scheme. In this method both the site and the treatment are randomly allocated creating a matched data of two outcome measures per participant. The order of site or treatment combinations are organised into six diverse schemes. The random blocks will be allocated by a data monitoring person to ensure that the principal investigator and the study subjects will not be involved in the allotment of treatment arms. Treatment for both the arms will be done by the same person. Each participant will be blinded to which side receives which etchant, and the evaluator will also be blinded to the treatment allocation. The investigator will be provided with a code indicating the treatment assignment for each half of the participants mouth. The treatment code will link the participants right or left half to their assigned treatment group. The investigator will apply both the etchants in the same way for the participants. After the treatment is done the participants will be sent to the outcome assessor for outcome measures. It will be ensured that the outcome assessors are independent of the treatment administration and blinded to the treatment assignment. They will not have access to the treatment codes or any information that could reveal the treatment allocation. After the completion of composite restoration following the standard protocol and will be sent to the outcome assessors immediately after at baseline 3 months and 6 months after the restoration. The outcome variables assessed are Retention, Marginal Integrity, Marginal discoloration, Surface texture, Postoperative sensitivity and Recurrent caries using the Modified USPHS Criteria.

Statistical analysis will be conducted. Descriptive statistics will be expressed as mean and SD. Categorical variables will be expressed as frequencies and percentages. A student t test and chi square test will be used for testing the association between the control and experimental groups for continuous and categorical variables respectively. For studying the changes by split mouth model in the same patient, a panel analysis will be utilized. Regression models will be used to analyse whether the treatment group has better outcomes over time compared to the control. Survival analysis will be employed by the KM curve and log-rank statistic and utilize the Cox Proportional Hazards Regressionfor identifying survival predictors. A p value less than 0.05 will be considered as statistically significant.

The study will adhere to ethical principles as outlined in the Declaration of Helsinki. Participants will be informed about the nature of the study, the procedures, and possible risks. Informed consent will be obtained from each participant. The study protocol got approval from the Institutional Ethical Committee and will be registered under the Clinical Trials Registry of India.

At the end of the study it is anticipated to obtain a favourable clinical outcome that supports the use of glycolic acid as an etchant for composite restorations. This study is expected to give evidence on the use of glycolic acid as an alternative to the phosphoric acid etchant in restoring non carious cervical lesions using composite restoration.