The purpose of this study was to compare the antiplaque efficacy of a 0,12% chlorhexidine and 0,05% cetyl-pyridinium chloride mouth rinse (Perio-aid®) with a 0,2% chlorhexidine non-alcohol base mouth rinse (Corsodyl Care®).

Dental plaque is a bacterial biofilm adhering to the tooth surfaces and is not the same in the different areas of the tooth: there is the supragingival, the plaque from the gingival margin and subgingival plaque. It is mainly composed of complex bacterial populations organized in a carbohydrate matrix also containing a small number of epithelial cells, leukocytes, macrophages and inorganic components such as calcium and phosphorus. This biofilm develops in virtually all places where there are damp surfaces and teeth are a very stable support for bacterial colonization. Mechanical oral hygiene procedures such as tooth brushing, dental flossing and inter-dental brushing is the most effective method for plaque removal but mouth rinses containing anti-microbials play an important role in maintaining oral health.

Chlorhexidine (CHX) digluconate, a cationic biguanide, is known to be an effective anti-plaque and anti-inflammatory agent and is the gold standard in chemical plaque control. The benefits of CHX are based on the high intra-oral substantivity and its bactericidal and bacteriostatic activities. This ingredient, when delivered orally, is free from systemic toxicity and microbial resistance, and supra-infections do not occur. It has been proven in several "in vitro" and "in vivo" studies, the safety and long-term efficacy of CHX mouth rinses. There have been suggested many indications for the use of this antiseptic and plaque control is one of the most important factors for proper healing after periodontal surgery and implant therapy.

The 0.2% CHX solution became the standard international concentration, due to his development in Europe but similar levels of plaque inhibition can be achieved with larger volumes of lower concentration solutions of CHX.

A lower concentration of CHX (0.12%) has been tested in several studies and has also been shown to confer clinical benefits. More important than the concentration of CHX seems to be the dose which balances efficacy against local side effects and user acceptability. The optimum dose is considered to be about 20 mg twice daily.

Clinically, the 0,12% CHX have been found to be similarly effective as 0.2% if the volume of the rinse was increased from 10 to 15 ml, yielding an 18 mg dose on each occasion but with respect to plaque growth inhibition, there is a small but significant difference in favour of the 0.2% CHX concentration.

CHX mouthrinses can have a variety of side effects and the most common, according to the manufacturers of these products, are loss of taste, tongue burning and irritation of the oral mucosa. Some brands have lowered the concentration of CHX in their mouthrinses and removed the ethanol in order to eliminate side effects such as soreness and to improve acceptability. A study concluded that the perturbation of taste perception after using 0.12% CHX is significantly lower than that after using 0.2% CHX. On the other hand, another studies concluded that there was no significant difference in terms of taste perception.

This study was a double-blinded, randomized two group parallel, to compare the antiplaque efficacy of two mouth rinses, during a 3-day plaque accumulation model, in periodontal healthy patients. After supragingival prophylaxis participants rinsed twice a day over a 72h non-brushing period. Primary outcome variable was plaque index. As secondary outcomes the taste and side effects variables were studied. Mann-Whitney, χ2 and Fisher's Exact tests were used to compare the variables

Inclusion Criteria:

• Good general health without a medical history or medication that might interfere with the conduct of the study
• Dentition with at least 24 teeth (minimum of five teeth per quadrant)
• Periodontal health, pockets < 5mm

Exclusion Criteria:

• Pregnant women or in lactation
• Participants with orthodontic or removable dental appliances
• Known allergies to CHX, CPC or to another ingredient of the mouth rinses
• Systemic antibiotic intake in the previous 3 months