It has been well established that the origin of gingivitis and periodontal diseases occurs by the colonization, accumulation and subsequent maturation of bacterial plaque, (Loe et al 1965, Socransky 1970), and mediated by the host immunological response (Lewis et al, 2004). Since, oral bacteria in plaque biofilms are an essential component in the dental diseases processes, most of current preventive oral health care focuses on thorough plaque removal so as to prevent, reduce or even reverse the disease condition. (Suomi 1971, Schmid et al 1976). In such endeavors of thorough plaque removal and especially prevention of its further accumulation, dental surgeons and hygienists have commonly recommended daily mechanical plaque removal, specifically tooth-brushing. Use of toothbrush to mechanically remove plaque is extremely effective, but yet is not able to remove it thoroughly from interdental areas when used alone (Hansen & Gjermo 1971) Routine use of dental floss in conjunction with tooth-brushing has been shown to reduce the onset and severity of gingivitis (Bergenholtz & Britton 1980, Carter-Hanson et al 1996) Patients' reluctance and inability to perform flossing on a regular basis has been mentioned (Kresh 1976). In addition, to plaque control, patients also utilize flossing to clear the interdental areas wherein food impaction has occurred (Gjermo & Flotra 1970). Schmid (1984) has classified interdental embrasures, depending upon the filling of the gingival embrasure by the interdental papilla. Hence in Type I, floss is used, and in Type II and III the incrementally wider proxabrush and unitufted brush are used respectively. Gomes et al have presented a modification in the use of knotted floss in wider embrasure areas. (Gomes et al 2016). The modification in the dental floss had been done so as to increase the effective width of the floss. This enables it to be used in embrasures wider than that recommended for conventional floss. In this modification, a knot is tied in the floss at any distance in the middle third of the floss length. The floss is inserted past the interdental contact point by the conventional finger flossing technique in the non-knotted area and then during the 'to and fro movement' on the tooth surface cervical to contact point, the knotted area is engaged through the embrasure (Gomes et al 2016) The purpose of this study is to compare the reduction of the clinical signs of plaque accumulation, gingival inflammation and gingival trauma in the area the knotted floss technique has been utilized versus the area where conventional flossing has been utilized in Type I gingival embrasures. Patients' acceptability of the knotted flossing technique will also be evaluated. This study is part of a larger study protocol involving different sample groups comparing the knotted floss technique with conventional dental flossing, use of inter-dental brushes and unitufted brushes in type II and type III embrasures as well.