Objective: This study aimed to evaluate the relationships between ocular protrusion and other craniofacial structures.
Methods: The lateral cephalograms of 124 nonsyndromic white adults were assessed. Two orbital and 13 craniofacial parameters were measured. Subgroups were constructed according to sex, anteroposterior position of maxilla, and mandibular plane angle values.Anatomical parameters and their relationships were statistically analyzed by analysis of variance and multivariate stepwise regression analysis.
Results: There were no significant differences in ocular protrusion distances between sexes, and between individuals with different maxillary anteroposterior position and mandibular plane angle values. Ocular protrusion distances, the distance between the eyeball apex and the lateral orbital margin (Eyeball apex-LOr: OP1) and inferior orbital margin (Eyeball apex-IOr: OP2), were found to be 20.6 ± 2.8 and 16.5 ± 3.1, respectively. However, regression analysis showed that the ocular protrusion distances had weak correlation with a few craniofacial structures. The OP1 had a low negative relationship with the maxillary anteroposterior position (N-Aperp) (r: -0.289) (P < 0.05). The OP2 had a low negative relationship with the palatal plane angle (FH/PP) (r: -0.291) (P < 0.01) but had a positive relationship with the cranial base angle (BSN) (r: 0.304) (P < 0.01) and posterior facial height (SGo) (r: 0.299) (P < 0.01).
Conclusions: Ocular protrusion distances did not differ by sex, maxillary anteroposterior position, and amount of mandibular plane angle and showed weak correlation with a few craniofacial structures. Ocular protrusion amounts can be used for diagnosis and treatment plan in craniofacial syndromic or nonsyndromic anomalies.