## 4 Discussion  
Based on the above results, all the research hypotheses were confirmed. The SNA angle is considered correct between 79-85 degrees [20]. Patients with UCLP after lip and palate fusion surgery had a mean score 79.1 degrees. This indicates a tendency towards a retrognathic maxilla. This was also confirmed by the results obtained by [PERSON] and coauthors [21]. Searching for the cause of reduced maxillary anterior growth in scientific reports, two positions are apparent. Some scientists describe the effect of cleft palate fusion surgery on reduced maxillary anterior growth [22, 23]. Others indicate [24] that retrognathic upper jaw also occurs in patients with UCL, suggesting a primary disturbance of growth factors regardless of the surgery performed. Comparing the results obtained by the authors, in which the group of patients with UCL obtained a mean SNA angle value 3 degrees higher than a mean SNA value in UCLP group, the authors tend to favor the first of these explanations. Moreover, the authors do not confirm the results of [PERSON] [24] and coauthors regarding reduced maxillary anterior growth in UCL patients. The SNB angle is considered correct in the range of 77-83 degrees [20]. The results present a tendency towards a retrognathic mandible in patients with UCL and UCLP. This is also confirmed by the results of [PERSON] and coauthors [25]. In patients with UCLP and UCL, the mean values of the ANB angle indicate the presence of a class II malocclusion. The same findings about patients with unilateral cleft lip and palate were obtained by [PERSON] and coauthors [26]. The group of patients without cleft--skeletal class II is also the most diagnosed malocclusion in the Polish population [27]. The causes of this abnormality are found, among others, in genetic factors, habits, but also in sagittal and vertical malocclusion disorders, which leads to skeletal compensation in the anterior-posterior plane [28]. With regard to the sagittal plane, crossbite is diagnosed in patients with UCL and UCLP [29, 30]. In the vertical plane, the results obtained by the authors confirm the tendency of mandibular downward rotation in patients with UCLP [25]. In unoperated patients with unilateral cleft lip and palate the genital angle presented a vertical growth pattern [31]. There were no differences regarding overjet between the UCL and UCLP groups. ADPI values were less than normal in both groups. Negative overjet was also described by [PERSON] and coauthors [32] among UCLP patients before orthodontic \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{2}{c}{**SNA**} & \multicolumn{2}{c}{**SNB**} & \multicolumn{2}{c}{**ANB**} \\ \cline{2-7}  & **r** & \(p\)**-Value** & **r** & \(p\)**-Value** & **r** & \(p\)**-Value** \\ \hline
**SNA** & - & - & **0.736** & ** & **0.001** & **0.444** & **0.014** \\ \hline
**SNB** & **0.736** & **\textless{}0.001** & - & - & \(-0.035\) * & 0.855 \\ \hline
**ANB** & **0.444** & **0.014** & \(-0.035\) * & 0.855 & - & - \\ \hline \hline \end{tabular} r—correlation coefficient; * [PERSON]’s correlation coefficient; ** Spearman’s Rank correlation coefficient.  
\end{table} 
Table 6: Summary of correlations between SNA, SNB, and ANB scores in the cleft lip group. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{2}{c}{**SNA**} & \multicolumn{2}{c}{**SNB**} & \multicolumn{2}{c}{**ANB**} \\ \cline{2-7}  & **r** & \(p\)**-Value** & **r** & \(p\)**-Value** & **r** & \(p\)**-Value** \\ \hline
**SNA** & - & - & **0.721** & ** & **0.001** & 0.249** & 0.184 \\ \hline
**SNB** & **0.721** & **\textless{}0.001** & - & - & **\textless{}0.430** & **0.018** \\ \hline
**ANB** & 0.249** & 0.184 & **\textless{}0.430** & **0.018** & - & - \\ \hline \hline \end{tabular} r—correlation coefficient; * [PERSON]’s correlation coefficient; ** Spearman’s Rank correlation coefficient.  
\end{table} 
Table 5: Summary of correlations between SNA, SNB, and ANB scores in the cleft lip and palate group. treatment.