Long-Term Occlusal Outcomes for Conservative Management in Patients With Robin Sequence

Robin sequence (RS), the triad of micrognathia, glossoptosis, and airway obstruction, is treated with conservative management in milder cases with the expectation that mandibular growth will normalize over time. Mandibular distraction osteogenesis (MDO) is a surgical intervention utilized in more severe cases. We aim to identify the long-term outcomes in conservatively managed RS patients to identify differences in mandibular growth and structural airway pathology.

A retrospective review of patients with RS at a tertiary pediatric hospital was conducted from 2002 to 2022. History and physical exam were reviewed to assess for dental occlusion, surgical history, and syndromic status. Both persistent micrognathia (Class II occlusion) and persistent malocclusion (Class II or Class III occlusion) required documentation after skeletal maturity. RS patients who had not yet achieved skeletal maturity were eliminated.

Fifty eight RS patients were included from 2281 records retrieved (44.9% CM, 55.1% (+) MDO). Conservatively managed patients frequently demonstrated malocclusion (76.9%) and crossbite (27.8%) to a lesser extent, with future surgery documented in 3.85% of cases. (+) MDO patients showed similar rates of malocclusion (59.4%) and crossbite (34.5%), with increased rates of future surgery (25%). Among (+) MDO patients, micrognathia persisted in syndromic patients (66.7%, n = 5) more often than in non-syndromic patients (52.9% n = 8).

Most RS patients retained micrognathia beyond skeletal maturity, conflicting with the self-correction model. Further studies should track RS patients treated conservatively to understand the rate of adult orthognathic surgery, assessing the varied distractor protocols and modalities currently available.

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