Objective: To track the development of sleep disordered breathing (SDB) as well as dentofacial morphology in cohort of children by having them complete a questionaire at ages 4, 6 and 12 . Clinical examination, sleep studies (at ages 4 and 12) and orthodontic evaluation were carried out on all who were reported to snore regularly and children who did not snore at all. Results: Out of the original group of 615 children, 64% (393) answered the inquiry on all three occasions. Of those, 27 snored regularly and 231 did not snore at all at the age of twelve.There were differences between those groups on all answers, especially prevalence of oral breathing: 78% versus 5% (p< 0.001). The prevalence of OSA decreased from 3.1% at the age of four to 0.8% at age 12 and the severity decreased from a mean AHI 14.8 at four to a mean AHI of 1.95 at age 12. The minimum prevalence of snoring regularly was estimated to 4.2% at 12 yrs compared to 5.3% at four, calculated for the original cohort of 644 children. The odds for a child who snored regularly at four or six years to be snoring regularly also at age 12 was 3.7 times greater than for a not snoring child in spite of surgery (OR 3.7, 95% CI 2.4-5.7). 63 children had undergone surgery due to snoring by age 12. 14 of them never snored and 17 snored regularly at the age 12. The dental arch was narrower in the children snoring regularly at four, six and 12 years compared to not snoring children. Cross-bites were more common among snoring children than among non snoring children, at four and six as well as at twelve. Conclusion: The prevalence of regular snoring is about the same from four to twelve years independent of surgery, but the prevalence of OSA decreased considerably. The children snoring regularly generally have a narrower maxilla compared to children not snoring. Surgery in young children is necessary but -cures‖ the snoring only temporary.