Few studies have examined, comprehensively and prospectively, determinants of oral-health-related quality of life. The aim of this study was to examine the relationships between psychosocial factors and oral health status, health perceptions, and quality of life. Measures of symptom and functional status, health perceptions, quality of life, oral health beliefs, and psychological (sense of coherence, self-esteem, health locus of control) and social factors (parents’ income and education) were collected from 439 12- and 13-year-olds at baseline and six-month follow-up, together with a clinical examination at baseline. Structural equation modeling indicated that increased levels of caries and more symptoms predicted more functional limitations, and, cross-sectionally, greater functional impact was associated with worse health perceptions, which were linked to lower quality of life. Sense of coherence was the most important psychosocial predictor. These factors are important in understanding how oral health affects young people’s daily lives.