Efficacy of an Antibacterial Toothpaste and Patients' Satisfaction

Agar Mitis salivarius with tellurium and bacitracin (MSTB) will be used for S. mutans isolation. The 0.1 ml saliva sample will be diluted with 0.9 ml of sterile normal saline; next, decimal dilutions of saliva will be made up to 10-3. Each medium plate will be cultured from 0.1 ml of the previously diluted sample to 10-3; then, the sample will be uniformly spread on the agar plates. Finally, the plates will be sealed. They will be incubated for 48 hours at 37°C. The bacterial colonies will be observed under a stereo microscope and identified by morphology and color. The CFU will be multiplied by the number of times the sample was originally diluted and expressed as the number of colony forming units per millilitre (CFU/mL) of saliva.

The plaque will be disclosed using a disclosing solution and recorded as follows: score 0 = absence of plaque; score 1 = separate flecks of plaque on the cervical margin; score 2 = a thin, continuous band of plaque [up to 1 mm] at the cervical margin of the tooth; score 3 = a band of plaque wider than 1 mm, but covering less than one-third of the tooth crown; score 4 = plaque covering at least one-third, but less than two-third of the crown of the tooth; score 5 = plaque covering 2/3-crown or more of the crown of the tooth.

A North Carolina periodontal probe (Hu-Friedy, Chicago, IL, USA) will be used for determine gingival index according to the following scale: score 0 = absence of inflammation; score 1 = mild inflammation-slightly slight change in color and little change in texture; score 2 = moderate inflammation-moderate glazing, redness, edema, and hypertrophy; score 3 = severe inflammation-marked redness and hypertrophy.

Patients with self-reported dentin hypersensitivity will be considered. A 1-s air blast from approximately 1 cm distance will be applied onto exposed dentine. The participant's response will be assessed using the 4-point Schiff Sensitivity Scale (from 0: participant does not respond, to 3: participant responds to stimulus, considers it painful, and requests discontinuation;

Participants' satisfaction before and after treatment will be recorded and the difference will be assessed. In order to obtain the data concerning patients' satisfaction with tooth color, a questionnaire containing aesthetic numeric visual-analogue scale ranging from 1 to 10 will be given to the subjects.