4,8,9 However, due to undesirable effects after prolonged use, such as pigmentation and taste disturbance, several phytopharmaceutical alternatives to chlorhexidine have been investigated.10,11,12,13,14,15 Higher figure 2 plants and aromatics have traditionally seen widespread use in folk medicine, and many have inhibitory properties against several groups of microorganisms.16,17 Plants from Brazilian biomes have been used extensively as natural medicines by local populations in the treatment of several tropical diseases, including fungal and bacterial infections.16 Lippia sidoides is a typical shrub commonly found in the Northeast Region of Brazil. Its camphoric foliage is indicated as a topical antiseptic agent for conditions of the skin and mucous membranes and also for throat infections.
10,18 The essential oil obtained from L. sidoides is composed mainly of thymol (56.7%�C59.65%) and carvacrol (16.7%�C19%). The other main compounds are caryophyllene (1.1%�C10.6%), p-cymene (7.1%�C9.08%) and myrcene (0.86%�C5.46%).18,19. The composition can vary greatly depending upon the geographic region of collection, variety, and age of the plant, as well as on the methods employed for drying and extraction of the oil.19 Previous studies have indicated that these major components of L. sidoides essential oil exhibit potent antimicrobial activity against oral pathogens18,20 and reduce the severity of gingivitis, dental plaque and histological inflammatory infiltrate in dogs.21 Recently, short-term clinical studies showed a positive effect of L. sidoides-based preparations as preventive agents.
10,22 These initial studies notwithstanding, no published controlled trials have evaluated the efficacy of a L. sidoides-based gel in the control of plaque and gingivitis. Thus, a clinical study in humans was conducted to evaluate the antiplaque and antigingivitis effects of this phytopharmaceutical agent and compare them to those of chlorhexidine. MATERIALS AND METHODS Subjects Thirty adult patients from the University of Fortaleza (15 female and 15 male, age 26�C47 years) were enrolled in this examiner-blinded, parallel, controlled clinical trial. All participants were randomly screened, were informed about the nature of the study, and provided written informed consent for participation, in compliance with the guidelines of the Brazilian National Health Council. The study protocol was approved by the institutional Research Ethics Committee (Co��tica/Unifor report 156/2008) The criteria for inclusion were a bleeding index (BI)23 30%, presence of at least 20 natural teeth, and absence of supragingival calculus and other plaque-retentive Brefeldin_A factors, such as dental caries and restoration excess.