The inverted-L osteotomy for mandibular distraction in Pierre Robin sequence (PRS) is a useful technique for avoiding injury to the tooth root and inferior alveolar nerve. Identification of the lingula is understudied and may decrease iatrogenic complications. This study aims to map the position of the lingula in the micrognathic mandible and compare the location of the lingula in relative normal mandible.
This is a retrospective cohort study of symptomatic PRS patients. Three-dimensional CT scans were reviewed and the relative lingula position described.
The study includes 11 PRS patients and 4 controls. The average measurements were overjet 9.99 (PRS) versus 4.28 mm (control) (P = 0.001), vertical ramus height 16.05 versus 23.04 mm (P = 0.003), and width 15.16 versus 20.67 mm (P = 003); horizontal ramus length 26.58 versus 40.62 mm (P = 0.001), gonial angle 132.64° versus 123.5° (P = 0.018); horizontal lingula position 7.25 versus 10.75 mm (P = 0.001), vertical position 9.02 versus 11.34 mm (P = 0.026). The ratio along the x-axis in PRS was 0.44 versus 0.52 in controls (P = 0.138); along the y-axis, the ratio was 0.57 versus 0.49 (P = 0.078).
Compared to normal controls, overjet is greater, vertical ramus height and widths are lesser, horizontal ramus length is lesser, and the gonial angle is greater in PRS patients. When analyzed as proportions along the height and width of the vertical ramus, there is no statistical difference (P > 0.05) in the position of the lingula between PRS patients and normal controls.
*Department of Plastic Surgery, University of Pittsburgh School of Medicine, PA, USA
†Department of Plastic and Reconstructive Surgery, The Johns Hopkins University School of Medicine Baltimore, MD, USA
Address correspondence and reprint requests to Anand R. Kumar, Department of Plastic and Reconstructive Surgery, The Johns Hopkins University School of Medicine, Johns Hopkins Childrens Center, 1800 Orleans Street, Bloomberg 7314A, Baltimore, MD, USA;. E-mail: firstname.lastname@example.org
Received 5 September, 2014
Accepted 29 March, 2015
The authors report no conflicts of interest.