## 2 Materials and Methods  
This study, designed as a retrospective analysis, obtained ethical approval from the Kirtkkale University Non-Interventional Research Ethics Committee (Decision number: 2022.03.30) and has been supported by project number 2022/115 from the Kirtkale University Scientific Research Projects Coordination Unit. Informed consent to participate was obtained from all the participants in this study. The inclusion and exclusion criteria for participants were defined to ensure the ideal positioning of brackets. These criteria included [15; 16; 17] the following:  
* No missing teeth in the mandible. To maintain statistical consistency when comparing the teeth only patients with a complete denti in the arch were included in this study. * Complete permanent dentition with all teeth fully erupted. Attention was given to ensuring the presence of fully erupted teeth for the correct placement of the brackets. * The mandible was used. Based on previous studies [18; 19], the mandible was preferred due to the minimal crowding when comparing this study and control group patients. * Crowding of less than 4 mm. * No active dental caries, fractures, dimensional anomalies, or dental prostheses. These criteria were selected to ensure that all participants had a stable and well-aligned dental structure, allowing for optimal bracket placement and minimizing potential confounding factors that could affect the outcomes of this study. The study group was selected from patients who were bracketed using rubber dam isolation during the pandemic, while the control group consisted of patients bracketed with mouth retractors and cotton rolls isolation. In the study by [PERSON] et al. [20], the mean values of bracket superimposition for the study group were found to be 1.10 \(\pm\) 1.19, while the mean values for the control group were 1.46 \(\pm\) 1.26. In our study, it was assumed that the 0.35-degree difference in superimposition between the two groups would be considered significant. The effect size (d) was calculated as 0.29, with 80% power and a 0.05 significance level. Based on these parameters, a minimum of 183 brackets per group, totaling 366 brackets, was required for this study. However, in our study, a total of 400 brackets were included. The calculations were performed using the 'GPower 3.1.9.2' software (Figure 1). To increase the power of this study, 400 brackets have been included. For each individual, a total of 10 teeth in the lower jaw, including the incisors, canine, first and second premolars, were examined, resulting in the assessment of a total of 400 brackets. A total of 40 individuals (21 females and 19 males, aged 15 to 25) were divided into two groups: the study group (12 females and 8 males, with a mean age of 21.2 years) and the control group (9 females and 11 males, with a mean age of 21.3 years). In this study, the group that received bracketing with rubber dam isolation (RDI) was designated as the study group, while the control group (TI--traditional isolation) included patients who underwent bracketing using a mouth retractor and cotton rolls. The flowchart of this study is presented in Figure 2.  
OptiDam(tm) (Kerr Hawe SA, Bioggio, Switzerland) rubber dam was used in the RDI group. The protrusions found on the rubber dam were punctured using a dental bur. The rubber dam was placed onto the teeth and secured with a clamp. To prevent the rubber dam from slipping coronally, a ligation process was performed using dental floss (Figure 3). In both groups, 0.022-inch MBT Prescription Gemini Twin brackets (3M Unitek, Monrovia, CA, USA) were used. The brackets were positioned according to MBT (McLaughlin, Bennett, Trevisi) guidelines [13], with measurements taken from the cusp or incisal edge using a gauge. Bonding was performed by the same operator with 4 years of experience (KKK). To determine the chair time with each patient, a stopwatch was managed by the dentist's assistant for all individuals.