Vertical Versus Horizontal Brushing: a Randomized Split-mouth Clinical Trial

Study population The study was conducted from October 2012 to December 2012 in the Dental Clinic of San Paolo Hospital in Milan. Sixty-one (61) students (19-24 years) attending the Dental Clinic were contacted with an information leaflet, explaining the aim of the study and requesting their participation with signed consent. Forty-nine (80.33% of total sample) agree to participate and underwent to an oral examination. The presence of seven evaluable teeth in each quadrant was considered the inclusion criterion. Exclusion criteria were the presence of oral mucosal lesions, periodontal pocket ≥ 4 mm, gingival recession, orthodontic treatment, caries lesions in buccal and/or lingual surfaces, removable prosthesis, use of mouthrinses containing plaque-reducing agents (e.g. chlorhexidine, essential oils, cetylpyridinium chloride) on regular basis.

One (1) subject was excluded because of the presence of periodontal pockets. Forty-eight (48) young adults were enrolled, five (10.42% drop-out rate) subjects did not attend the scheduled appointment and so the study reports data on 43 subjects.

All subjects were given a thorough professional prophylaxis to remove plaque, stains and calculus. The study protocol was approved by the Ethical Committee of San Paolo Hospital.

Study design and calibration of the personnel The study was designed and performed as split-mouth design. The subjects were listed and a list of true random numbers was generated (www.random.org). The generator was set to produce a true random sequence of "1" and "2", where "1" represented a mouth in which first and third quadrants were brushed with vertical method and "2" in which second and fourth quadrants were brushed with the same method.

A dental hygienist performed the brushing sessions. A calibration course was carried out one week before the starting of the study. She applied the two brushing methods first on Columbia Dentoform® and after on 2 volunteers.