Miswak chewing sticks are prepared from the roots or twigs of Salvadora persica plants. They are widely used as a traditional oral hygiene tool in several African and Middle Eastern countries. The aim of this study was to assess and compare the periodontal status of adult Sudanese habitual miswak and toothbrush users. The study population comprised male miswak users (n = 109) and toothbrush users (n = 104) with age range 20-65 years (mean 36.6 years) having 18 or more teeth present. They were recruited among employees and students at the Medical Sciences Campus in Khartoum, Sudan. One examiner used the Community Periodontal Index (CPI) to score gingival bleeding, supragingival dental calculus, and probing pocket depth of the index teeth of each sextant. In addition, the attachment level was measured, which, along with the CPI, was used to assess the periodontal status of the two test groups. Gingival bleeding and dental calculus were highly prevalent in the study population. Approximately 10% of the subjects had > or =4 mm probing depth and 51% had > or =4 mm attachment loss in one or more sextants. Subjects in the age group 40-65 years had a significantly (p < 0.05) higher number of sextants with gingival bleeding and with > or =4 mm probing depth and attachment loss than the 30-39 years group. Miswak users had significantly (p < 0.05) lower dental calculus and > or =4 mm probing depth and higher > or =4 mm attachment loss as well as a tendency (p = 0.09) to lower gingival bleeding in the posterior sextants than did toothbrush users. These differences were not significant in the anterior sextants. It is concluded that the periodontal status of miswak users in this Sudanese population is better than that of toothbrush users, suggesting that the efficacy of miswak use for oral hygiene in this group is comparable or slightly better than a toothbrush. Given the availability and low cost of miswak, it should be recommended for use in motivated persons in developing countries.