A two-year longitudinal study of dental caries in permanent first molars of Korean elementary schoolchildren

Objective: This longitudinal study investigated dental caries increment in permanent first molars of Korean elementary schoolchildren. Methods: A conv enience sample of 722 children aged 7-9 years attending one urban elementar y school was examined at baseline, with follow-up examinations at one and t wo years, Coronal surfaces of permanent first molars were scored with regar d to caries experience and sealant status. Results: Among sound occlusal su rfaces at baseline 21 percent of upper and 25 percent of lower surfaces dev eloped caries during the two-year interval. In teeth that erupted between b aseline and the first follow-up exam, over 10 percent of occlusal surfaces developed caries. Pit and fissure caries accounted for 93 percent of all ne w carious surfaces, while sealants had been placed on 16 percent of occlusa l surfaces during the study. Conclusions.. Recognizing the limitations of t his convenience sample, dental sealants should be used more widely in this Korean population and should be applied soon after tooth eruption.