Early Mandibular
Distraction Osteogenesis
in Pierre Robin Sequence
Pierre Robin Sequence
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Pierre Robin case report 1926
one in 9000 births
micrognathi, glossoptosis, cleft palate.
Theories:
– fetal head positioning, frequently associated with
oligohydramnios.
– a delay in neurological maturation
– rhombencephalic dysneurulation
• rare familial cases reported - localized intrinsic
failure of mandibular growth may be a factor in
some cases.
• Catchup mandibular growth in most, but
mandibular dimensions will remain below agematched norms.
Early Considerations
• varying degrees of airway obstruction and feeding
difficulties.
• mechanism - falling back of the tongue into the oral
pharynx.
• Immediate supportive measures required in over 70
percent of affected infants.
• Caouette-Laberge ( 1994) clinical classification of
respiratory symptoms:
– group I, adequate respiration in prone position and bottle
feeding;
– group II, adequate respiration in prone position but feeding
difficulties requiring NGT;
– group III, children with respiratory distress requiring
respiratory support and NGT.
Early Management
• Supportive measures
• Lying prone
• Tongue-lip adhesion
– Kirschner (2003) - >40% Group III infants required
tracheostomy after tongue-lip adhesion
– Denny (2004) - additional 1.9 secondary
procedures
• Nasopharyngeal airway
• Tracheostomy (12-42%)
• K wire fixation, genioglossus stripping
Problems with tracheostomy
• Increased morbidity
– Donnelly, Int J Pediatr Otorhinolaryngol. 1996
• n=29; 41% complication rate (<1yo- 64%)
• 25 months average decannulation
– Midwinter, J Laryngol Otol. 2002
• n-=143; 46% complication rate
• 25 months mean decannulation
• Mortality 2.7%
– Carr, Laryngoscope. 2001
• N=142; 43% serious complications
• Mortality 0.7%
Problems with tracheostomy
• Poorer Speech Outcomes
– Jiang, Int J Pediatr Otorhinolaryngol. 2003
• Affects speech and language development in those
with and without neurological disorders.
• Risk factors: age at tracheostomy, and duration.
• Better outcome with early decannulation
– Simon, Int J Pediatr Otorhinolaryngol. 1983
• All children decannulated during the linguistic stage
exhibited specific spoken language delays
• phonological impairment proportional to duration
Problems with tracheostomy
• Prolonged
– Tomaski, Laryngoscope 1995
• Average 3 years decannulation in PRS
• Carer Impact
• Financial Burden
• Developmental Problems
– Singer, Dev Med Child Neurol. 1989
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n=130
Slower growth rate
Higher risk of behavioural problems
Most will require special educational intervention
Mandibular Distraction:
Background
• External
traction with
halo (Callister
1937)
Mandibular Distraction:
Background
• External traction
with pulley/
weight
(Longmire,
Sandford 1940)
Mandibular Distraction:
Background
• Mandibular DOG
– McCarthy 1992, Molina/Ortiz-Monasterio 1995
• Use in children with airways obstruction
– Moore, David 1994
– Cohen 1999
• Use in Pierre Robin
– Denny 2001,2002
– Monasterio 2002
– Burstein 2005 (internal resorbable device)
Mandibular Distraction:
Background
• External distractor (Denny 2002)
– linear Howmedica distraction device
Mandibular Distraction:
Background
Mandibular Distraction:
Background
Mandibular Distraction:
Background
• Internal resorbable device
Early Distraction: Controversies
• Conservative management alone
– 20-40% will not respond to positioning or glossopexy
• Rapid distraction
– 2mm/day vs 1mm/day
– In goats – demyelination noted at 2mm/day (Hu, J Oral
Maxillo Surg 2001)
• Effect on dentition
– Screw holes
– Infraalveolar nerve
• Effect on subsequent mandibular growth
• Facial scarring
Indications for early distraction
in Pierre Robin
• Failure of conservative measures to
improve respiration and feeding
• Documented tongue base obstruction
• Center with expertise In distraction