Are distinct etiologies of upper airway obstruction in mouth-breathing children associated with different cephalometric patterns?

OBJECTIVE: To test the null hypothesis that mouth-breathing (MB) children by distinct obstructive tissues present a similar cephalometric pattern. METHODS: The sample included 226 prepubescent children (113 MB and 113 nasal breathing (NB) controls). An ENT clinical examination, including flexible nasal endoscopy, orthodontic clinical and cephalometric examinations, was performed on the MB population. MB children were grouped into three categories, according to the obstructive tissues: 1) adenoid group (AG), 2) tonsillar group (TG), and 3) adenotonsillar group (ATG). The NB controls were matched by gender, age, sagittal dental relationship and skeletal maturation status. Lateral cephalometric radiography provided the cephalometric pattern comparisons between the MB and NB groups. RESULTS: MB cephalometric measurements were significantly different from those of NB children, exception in the SNB° (P=0.056). All comparisons between the three groups of MB children with the NB children showed a significant difference. Finally, even among the three groups of MB children, a significant difference was observed in the measurements of the SNB° (P<0.036), NSGn° (P<0.028) and PFH/TAFH ratio (posterior facial height/total anterior facial height) (P<0.012). CONCLUSIONS: The cephalometric pattern of MB and NB children was not similar. Cephalometric measurements of the MB group differed according to the etiology of upper airway obstruction. Children with isolated hypertrophy of the palatine tonsils presented with a mandible that was positioned more forward and upward compared to children obstructed only by the enlarged adenoid.

Mouth breathing children and cephalometric pattern: does the stage of dental development matter?

OBJECTIVE: To test the hypothesis that there is no difference in the cephalometric pattern between mouth breathing children with primary dentition and mixed dentition. METHODS: Cephalometric measurements of 126 mouth breathing children (MB) were compared to 126 nasal breathing controls (NB). Both groups were divided into deciduous dentition (mean age 4 years, 8 months) and mixed dentition (mean age 7 years, 9 months) groups. RESULTS: A statistically significant difference was observed in the dentofacial patterns of MB children compared to NB children. The total length of the mandible was smaller in MB compared to NB children. However, this difference was found only in subjects with mixed dentition. The length of the mandibular corpus is similar in MB and NB children, although older MB children with mixed dentition had significantly smaller measurements. The lower anterior facial height was higher in MB compared to NB children, but this difference was evident only in younger children with primary dentition. Mandibular plane angle, Y-axis angle and lower anterior facial height to total anterior facial height ratio were greater, and posterior facial height to total anterior facial height ratio was smaller in MB than NB children, indicating that mouth breathers had a more vertical facial growth pattern. However, no differences were found in the vertical growth pattern associated with the stage of dental development. The ANB angle was not associated with the maturational status of occlusion. Linear measurements and the gonial angle were significantly different between children with primary and mixed dentition, but such differences were associated with normal vertical growth. CONCLUSIONS: The present investigation rejected the null hypothesis and showed significant cephalometric differences between primary and mixed dentition MB children. Mouth breathing children in the mixed dentition have a smaller mandible (in terms of total length and corpus length) than nasal breathers. In children with primary dentition, the lower anterior facial height is higher in MB than in NB children. There was no significant association between the stage of dental development of mouth breathing children (either in the primary or mixed dentition) and the other cephalometric patterns.