(5) Maxillomandibular Development After Mandibular Distraction Osteogenesis in Patients With Isolated Pierre Robin Sequence: A Quarter Century Review

Thursday, September 15, 2022

1:30 PM – 3:00 PM CDT

Presenting Author(s)

Katelyn Kondra, MD

Resident
Keck Medicine of USC
Los Angeles, California, United States

Co-Author(s)

Kimiko Agari, MD, DDS

Resident
Children's Hospital Los Angeles
Los Angeles, California, United States
Eloise Stanton, BA

Medical Student
Keck School of Medicine of USC
LOS ANGELES, California, United States
Christian Jimenez, BS

Medical Student
Keck School of Medicine of USC
Los Angeles, California, United States
LB

Lamia Binhuwaishel, BDS, MS

Resident
King Saud Medical City
Los Angeles, California, United States
AA

Abdullah Albawardi, DMD, MS

Resident
Children's Hospital Los Angeles
Los Angeles, California, United States
Allen Huang, MD, DDS

Resident
Children's Hospital Los Angeles
LOS ANGELES, California, United States
SY

Stephen Yen, DMD, PhD

Orthodontist
Children's Hospital Los Angeles
Los Angeles, California, United States
MU

Mark M. Urata, MD, DDS

Attending Physician
Children's Hospital Los Angeles
Los Angeles, California, United States
JH

Jeffrey Hammoudeh, MD, DDS

Attending Physician
Children's Hospital Los Angeles
Los Angeles, California, United States

Disclosure(s):

Katelyn Kondra, MD: No financial relationships to disclose

Kimiko Agari, MD, DDS: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Eloise Stanton, BA: No financial relationships to disclose

Christian Jimenez, BS: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Lamia Binhuwaishel, BDS, MS: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Abdullah Albawardi, DMD, MS: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Allen Huang, MD, DDS: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Stephen Yen, DMD, PhD: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Mark M. Urata, MD, DDS: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Jeffrey Hammoudeh, MD, DDS: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Abstract: Mandibular distraction osteogenesis (MDO) is an effective treatment for obstructive sleep apnea (OSA) in infants with microretrognathia¹; this is particularly beneficial for patients with isolated Pierre Robin sequence (iPRS). Without intervention to improve the upper airway, patients may require tracheostomy. It is generally accepted that these patients develop with disproportionate maxillomandibular growth post-distraction; yet, the timeline for relapse to class II and differences across sexes are not well-described². This study characterizes a timeline of maxillomandibular growth for patients with iPRS after over-distraction with MDO.
A retrospective review was conducted for patients with iPRS who underwent MDO at CHLA between 1995 to 2021. We identified patients with postdistraction lateral cephalograms, from which Steiner’s analysis was abstracted to determine skeletal classification. Data were analyzed with SPSS software Version 28.0 (SPSS Inc., Chicago, IL). Descriptive statistics and tests of statistical significance were performed, including Student’s t-test, X², multiple linear regression, and correlation analysis. A statistically significant result was indicated by a value of p < 0.05.
Of 118 patients who underwent MDO, 81 had iPRS, 28 of whom had >1 postoperative lateral cephalogram. All patients were in skeletal class II before undergoing MDO with distraction to 30 mm. Average time from surgery to initial cephalogram was 60.93 months; 18 patients (64.29%) had an ANB > 4º (class II) at 60.50 ± 24.35 months postoperatively; 8 patients (28.57%) had an ANB 0-4º (class I) at 63.88 ± 28.57 months postoperatively; and 2 patients (7.14%) had an ANB < 0º (class III) at 53.00 ± 29.70 months postoperatively. Eleven patients received a second cephalogram 121.09 months ± 31.81 postoperatively. The 2 patients initially in class III at the first cephalogram reverted to class I by the second cephalogram; 0 patients remained in class III. Evaluation across sexes demonstrated 56.6% (10/18) of males and 50.0% (5/10) of females were in class II (p=0.778).
We demonstrate that most patients regress into a skeletal class II 5 years postoperatively; no patients remained prognathic 10 years postoperatively. These changes may be from delayed growth of the micrognathic mandible coupled with inherent relapse following distraction. These results can help clinicians understand the mandibular growth potential after MDO, guide surgeons to distract to class III, and provide parents with expectations for their child’s craniofacial development after distraction.

1. Deguchi T Sr, Katashiba S, Inami T, Foong KWC, Huak CY. Morphologic quantification of the maxilla and the mandible with cone-beam computed tomography. Am J Orthod Dentofacial Orthop. 2010;137(2):218-222.
2. Gürsoy S, Hukki J, Hurmerinta K. Five year follow-up of mandibular distraction osteogenesis on the dentofacial structures of syndromic children. Orthodontics & Craniofacial Research. 2008;11(1):57-64. doi:10.1111/j.1601-6343.2008.00415.x