4Zhu L, Petersen PE, Wang HY, et al. Oral health knowledge, atti- tudes and behaviour of children and adolescents in China [ J ]. lm Dent J,2003,53 (5) :289 - 298.
6Petersen PE. Oral health behaviour of 6-year-old Danish children [ J]. Acta Odontol Scand, 1992,50:57 - 64.
7Chestnut IG, Schafer F,Jacobson APM, et al. The influence of to- othbrushing frequency and post-brushing rising on caries experi- ence in a cariea clinical trial[ J]. Community Dent Oral Epidemi- o1,1998,26(6) :406 -411.
8Ismail AI,Tanzer JM,Dingle JL. Current trends of sugar consumption in developing societies. Community Dent Oral Epidemiol,1997,25:438-439.
9Chestnutt IG, Schafer F, Jacobson APM, et al. The influence of toothbrushing frequency and post - brushing rising on caries experience in a caries clinical trial. Community Dent Oral Epidemiol,1998,26:406-411.
10Newman HN, Wefel JS. The development of dental plaque: from perceptive primary cuticle to acquired pellicle to dental plaque to calculus formation. In 5th edition. Harris NO, Garcia-Godoy F. Primary Preventive Dentistry. Printed in USA by Appleton & L