Abstract
Background and Objectives: Halitosis poses a clinical and psychosocial burden, particularly in orthodontic contexts where plaque retention can exacerbate odor production. This cross-sectional study aimed to compare halitosis and oral health-related quality of life (OHRQoL) in three distinct groups: patients wearing removable clear aligners, patients with lingual orthodontic brackets, and non-orthodontic controls. We further explored dietary factors (frequent snacking vs. infrequent snacking) to identify their influence on halitosis severity and self-perceived well-being. Methods: A total of 162 participants (55 aligners, 58 lingual brackets, 49 controls) were recruited. Halitosis was assessed by the Halitosis Associated Life-Quality Test (HALT) questionnaire (range 0-100) and an organoleptic evaluation (range 0-5). OHRQoL was examined with the OHIP-14 instrument (range 0-56). Data on frequent vs. infrequent snacking were also recorded. One-way ANOVAs with Tukey's post hoc and chi-square tests were utilized for group comparisons. Spearman's correlation examined relationships between HALT scores, organoleptic measures, and OHIP-14. A significance threshold of p < 0.05 was adopted. Results: Aligner users demonstrated lower mean HALT scores (31.7 ± 5.8) compared to the lingual group (37.4 ± 6.2, p = 0.001) and controls (34.6 ± 6.0, p = 0.039). Lingual bracket wearers had the highest mean organoleptic score (2.4 ± 0.6, p < 0.001). Frequent snackers exhibited worse HALT outcomes (36.9 ± 6.3) than infrequent snackers (32.6 ± 5.9, p = 0.005). A correlation analysis showed a moderate positive correlation (r = +0.52, p < 0.001) between HALT and organoleptic scores and a strong negative relationship (r = -0.63, p < 0.001) between HALT and OHIP-14. Conclusions: Removable aligner use correlated with lower self-reported halitosis and better OHRQoL relative to lingual brackets. Frequent snacking appeared to aggravate halitosis across all groups. These findings emphasize the importance of tailored oral hygiene measures, dietary counseling, and orthodontic appliance selection to mitigate halitosis and enhance overall well-being.