Prospective study of the caries recurrence risks after severe early childhood caries treatments under general anesthesia

Objective: To study prospectively the caries characteristics of the children who suffered severe early childhood caries (S-ECC) and received dental caries treatment under general anesthesia and to explore the related risk factors of caries recurrence after treatment. Methods: During December 2012 to August 2014, eighty-three children aged 2-4 years with S-ECC who underwent one caries treatment session under general anesthesia in Peking University School and Hospital of Stomatology participated in this study. Data of demographics, clinical characteristics, dietary and oral hygiene habits of the participants were collected before the treatment and 1-, 7- and 13-months after the treatment. All data were then analyzed to find out whether the factors were related to caries relapse. Results: Among the 70 children who completed 7-13 months follow-up, twenty-nine children (41%) remained caries-free and 41 children (59%) had a few caries recurrence during the observation period. All the teeth suffered different variation of caries recurrence except mandibular deciduous incisors. As for the types of caries recurrence after caries treatment under general anesthesia, the maxillary deciduous incisors usually showed secondary caries (new caries/secondary caries numbers were 1/12), the canines and first deciduous molars occurred both secondary and new caries (new caries/secondary caries numbers in canines were 12/6, in first deciduous molars were 16/12) and the second deciduous molars usually presented new caries (new caries/secondary caries numbers were 19/5). After treatment, the prone tooth surfaces of caries recurrence from high to low were: adjacent surfaces of deciduous molars (37 surfaces), occlusal surface of deciduous molars (28 surfaces), adjacent surfaces of deciduous canines (13 surfaces), buccal and lingual surfaces of deciduous molars (12 surfaces), labial and lingual surfaces of deciduous incisors (10 surfaces), labial and lingual surfaces of deciduous canines (8 surfaces) and adjacent surfaces of deciduous incisors (5 surfaces). There were no significant differences in the children's demographics and clinical characteristics between relapse and non-relapse groups (P>0.05). Patients in the relapse group had higher sugar intake frequencies than those in the non-relapse group at both 7- and 13-month follow-ups (P<0.05). Conclusions: Children of 2-4 years old with S-ECC have a high risk of caries recurrence after caries treatment under general anesthesia and need to recieve regular oral examination. During the follow-ups, the prevention and treatment of new and secondary caries of deciduous molars and secondary caries of deciduous incisors should be focused on. High frequency of sugar intake is an important risk factor of recurrent caries for children with S-ECC after caries treatment.