This study was a part of the 7th National Oral Health Survey of Thailand and aimed to assess overall and condition-specific oral health-related quality of life of 12 and 15 year olds. Oral impacts were assessed using the Child-Oral Impacts on Daily Performances Index for 12 year olds and the Oral Impacts on Daily Performances index for 15 year olds. Overall oral impacts and condition-specific oral impacts (CS-impacts) were calculated. Detailed characteristics of CS-impacts were analyzed. Seventy-five percent of 12 year olds and 70.1% of 15 year olds had one or more oral impacts. CS-impacts attributed to dental caries were 37.8% and 36.5% for 12 and 15 year olds, respectively, followed by CS-impacts attributed to periodontal diseases and oral lesions. Dental caries was the most important cause of oral impacts. The severe impacts on daily performances of 12 year olds were mainly caused by dental caries, while those of 15 year olds related to dental caries and oral lesions. The majority of Thai children and adolescents experienced oral impacts. CS-impacts attributed to dental caries were most prevalent and most severe.
Keywords: adolescent; children; condition-specific oral impact; national survey; oral health–related quality of life.