Evaluation of the Pittsburgh Sleep Quality Index in a Group of Orthodontic Patients With Different Sagittal Skeletal Relationships

Background This study aimed to evaluate and compare the subjective sleep quality of Thai orthodontic patients classified into skeletal class I (Sk-I), class II (Sk-II), and class III (Sk-III) groups using the Thai-Pittsburgh Sleep Quality Index (Thai-PSQI). Methods A total of 93 orthodontic patients undergoing treatment were included in the study. Cephalometric analysis using Dolphin Imaging software classified participants into Sk-I, Sk-II, and Sk-III groups. Sleep quality was assessed using the Thai-PSQI. Data normality was tested using the Shapiro-Wilk test. The Kruskal-Wallis test was used to compare Pittsburgh Sleep Quality Index (PSQI) scores among skeletal groups. Demographic characteristics and differences in sleep-related parameters (sex, age, and body mass index) between good and poor sleepers were analyzed using the Chi-square test and Mann-Whitney U test (α = 0.05). Results The Sk-II group had the highest PSQI scores, followed by the Sk-I and Sk-III groups (6.68 ± 3.39, 6.42 ± 2.71, and 6.26 ± 2.46, respectively), indicating poor quality across all groups. However, no statistically significant differences were observed in PSQI scores among the skeletal groups (p > 0.05). Similarly, the distribution of good and poor sleepers was not significantly different among the Sk-I, Sk-II, and Sk-III groups (p > 0.05). In addition, there was no significant difference in sleep-related parameters between good and poor sleepers (p > 0.05). Conclusions Sleep quality is not influenced by sagittal skeletal patterns. Therefore, incorporating sleep quality assessments into orthodontic treatment planning may be beneficial.