Transactions of an international conference. Worldwide concern: better dental care for more people. An international collaborative study. How oral surveys were conducted.

A special form and field manuals defining examination criteria were prepared for recording the following: 1. Number of teeth present both primary and permanent 2. Periodontal disease (a) Oral hygiene using the simplified oral hygiene index. (b) Periodontal condition using a modified P.I. index. (c) Periodontal treatment requirements. 3. Dental caries The DMF index was used with separate coding for filled or crowned teeth having additional primary or secondary decay. 4. Dento facial anomalies Both treatment need and treatment status were recorded. 5. Prosthetic status Possession and requirements for partial or full dentures and bridges were recorded for the age groups 13-14 and 35-44. 6. Oral pathology Pathological conditions of the gingiva and oral mucosa. 7. Need for immediate attention Conditions causing or likely to cause pain or danger to general health unless immediate treatment was given. The recording was carried out using fibre optic illumination, disposable mirrors and sickle probes. X-rays were not utilized. Two roving epidemiologists first established reproducible criteria and then calibrated the local examiners. Re-calibration took place at intervals and repeat examinations of a small sample population ensured reproducibility of recordings. The completed charts were sent to the WHO Oral Health Unit where they were edited and the data transferred to computer tape for analysis. For the present reports three variables--number of carious teeth, caries treatment/need ratio and number of teeth with gingivitis were selected for special study.