Clefts of the secondary palate referred to the Oslo Cleft Team: epidemiology and cleft severity in 994 individuals.

OBJECTIVE: To describe Norwegian individuals born with cleft of the secondary palate (CP) in relation to cleft severity, Pierre Robin sequence, associated anomalies, syndromes, and hypodontia and to present estimated longitudinal prevalences.

PATIENTS: Nine hundred ninety-four individuals with CP born between 1960 and 2002 referred to the Oslo Cleft Team (OCT).

METHOD: Data were collected retrospectively from the archives of the OCT.

RESULTS: Among all CP, 7.6% had recognized syndromes, 30.5% had associated anomalies, and in 61.9%, CP was the only malformation. Pierre Robin sequence was recorded in 11.7%. Female predominance was observed both in general and in each cleft severity subgroup. Of 610 individuals with CP, only 25.1% were diagnosed with a submucous cleft palate, 45.9% had a cleft of the soft palate only, and in 29%, the cleft extended into the hard palate. Among 309 individuals over the age of 10 years with CP only, hypodontia was found in 28.5%, and in individuals with Pierre Robin sequence, hypodontia was found in 44.1%. During the period 1965 to 1999, the estimated prevalence of individuals with CP in the OCT uptake area was found to be 0.59 per 1000 live births. The estimated prevalence increased slightly over time, both overall and within the cleft severity subgroups.

CONCLUSION: A large proportion of a Norwegian population with CP had syndrome or additional anomalies. The estimated prevalence of CP in this population increased slightly during the observation period.