1. Todd JE, Lader D (1991) Adult Dental Health Survey 1988. London: HMSO.
2. Cadlas AF, Marcenes W, Sheiham A. Reasons for tooth extraction in a Brazilian population Int Dent J 2002; 50: 267–273.
3. Summerfield C, Babbs P. National Statistics Social Trends No 33 2003. London: TSO.
4. Insalaco R. Annual Abstract of Statistics No 138 2002. London: The Stationary Office.
5. Kelly M, Steele J, Nuttall N et al. Adult Dental Health Survey - Oral Health in the United Kingdom 1998 2000. London: The Stationary Office.