## 4 Discussion  
The goal of this research was to evaluate the reliability of ClinCheck(r) accuracy of Invisalign(r) therapy in adults with class I malocclusion and non-extraction cases in all four dimensions. To the best of our knowledge, no previous study has evaluated the reliability of ClinCheck(r) using only the iTero evaluation tool. This study aimed to compare predicted and achieved movements of teeth with respect to the sagittal, vertical, transverse, and arch length dimensions using only ClinCheck(r) to compare before and after. Previous studies measured the accuracy of ClinCheck(r) reliability by using various research tools, such as the American Board of Orthodonics Objective Grading System (ABO OGS) by [PERSON] et al. [18] and Tooth Measure(r) by [PERSON] et al., [PERSON] et al., and [PERSON] et al. [7; 19; 20]. Despite these research tools having the ability to provide a method of accuracy assessment, a simple and convenient method of assessing accuracy is using ClinCheck(r) itself to compare initial, current, and predicted movements before and after treatment. It is our belief that including more than one software would complicate the results and introduce more room for error; however, the algorithm and validity of the ClinCheck measurements is unknown and has yet to be released by Align Technology(r)[10]. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Parameter** & **Clinic** & **Percent Mean Accuracy (\(\pm\)SD)** \\ \hline Overjet & Clinic 1 & 80.32 (\(\pm\)15.05) \\ \hline  & Clinic 2 & 74.78 (\(\pm\)17.68) \\ \hline  & Clinic 3 & 72.95 (\(\pm\)24.49) \\ \hline  & Clinic 1 & 96.42 (\(\pm\)2.96) \\ \hline  & Clinic 2 & 97.01 (\(\pm\)2.73) \\ \hline  & Clinic 3 & 95.83 (\(\pm\)3.22) \\ \hline Overbite & Clinic 1 & 61.35 (\(\pm\)23.70) \\ \hline  & Clinic 2 & 58.62 (\(\pm\)25.73) \\ \hline  & Clinic 3 & 59.62 (\(\pm\)23.76) \\ \hline Upper Intercanine Width & Clinic 1 & 98.60 (\(\pm\)1.28) \\ \hline  & Clinic 2 & 98.86 (\(\pm\)0.80) \\ \hline  & Clinic 3 & 97.22 (\(\pm\)3.22) \\ \hline Lower Intercanine Width & Clinic 1 & 98.21 (\(\pm\)2.04) \\ \hline  & Clinic 2 & 97.07 (\(\pm\)3.78) \\ \hline  & Clinic 3 & 97.50 (\(\pm\)2.49) \\ \hline Upper Intermal Width & Clinic 1 & 98.08 (\(\pm\)1.77) \\ \hline  & Clinic 2 & 97.73 (\(\pm\)3.12) \\ \hline  & Clinic 3 & 97.18 (\(\pm\)3.72) \\ \hline Lower Intermal Width & Clinic 1 & 98.53 (\(\pm\)1.43) \\ \hline  & Clinic 2 & 98.34 (\(\pm\)1.39) \\ \hline  & Clinic 3 & 96.92 (\(\pm\)4.23) \\ \hline Upper Crowding & Clinic 1 & 38.50 (\(\pm\)25.71) \\ \hline  & Clinic 2 & 44.07 (\(\pm\)27.23) \\ \hline  & Clinic 3 & 37.20 (\(\pm\)26.67) \\ \hline Lower Crowding & Clinic 1 & 30.42 (\(\pm\)27.85) \\ \hline  & Clinic 2 & 31.67 (\(\pm\)24.22) \\ \hline  & Clinic 3 & 29.19 (\(\pm\)24.51) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Comparison of the accuracies between the different centers. In terms of demographic data, we had a total sample size of 206 patients, which is the largest in the literature thus far. [PERSON] et al. [7] had a sample size of 50, [PERSON] et al. [19] had a sample size of 116, [PERSON] et al. [18] had a sample size of 27, [PERSON] et al. [20] had a total of 37, [PERSON] et al. [9] had a total of 64, and [PERSON] et al. [10] had a total of 57. Moreover, we included samples from three different practices which offered us diversity. Most of the studies mentioned above were single-center studies which increases the risk of bias [10; 18; 19]. Few studies included more than two centers [9; 21]. Upon assessment of the sagittal dimension, the overjet and interincisal angle were assessed. In terms of overjet, we reported a mean difference of 0.2 \(\pm\) 1.1 mm, which is in accordance with [PERSON] et al. [7] who reported a mean difference of 0.34 \(\pm\) 0.54 mm; however, it is important to note that they included 15-year-old patients in their study which means growth could have been a factor in the decrease in overjet. With regards to the interincisal angle, we reported a 96% accuracy, whereas [PERSON] et al. [8] reported only 50%.