First-time expectant mothers and their husbands will be recruited. The recruited families will be randomly allocated to the test and control groups. In the test group, personal hygiene instruction (OHI) for the expectant mothers and their husbands together with oral health education materials on infant's tooth development and eruption, establishment of proper feeding, dietary and toothbrushing habits will be given before the delivery of the new born babies. Reinforcement of OHI and demonstrations on how to clean the infant's oral cavities and perform toothbrushing will be delivered after the babies are born. Comprehensive data will be collected from the mothers, fathers and the infants in both the test and control groups at different time points through dental examination, biological testing and questionnaire survey. The CONSORT statement will be strictly followed when conducting the clinical trial, analyzing the data and reporting the results.