Paul Hunter DMD, MLIS
A comparison of 0.12 percent to 0.2 percent chlorhexidine indicates that there is a small difference on plaque accumulation, no effect on gingivitis, and a lack of research for periodontal pocketing or attachment levels.
Dentists may expect limited clinical difference on plaque accumulation between 0.12 percent and 0.2 percent chlorhexidine.
What is the difference of the effects of 0.12 percent compared to 0.2 percent chlorhexidine (CHX) mouthrinse on periodontal parameters in adult patients?
The authors searched the English-language literature in two databases, and handsearched reference lists of relevant studies and review papers published through February 2010. They used an extensive search strategy, which included various keywords and subject headings. Two of the authors independently assessed the resultant searches for randomized controlled trials and controlled clinical trials that directly compared the two concentrations of CHX on plaque, bleeding, gingivitis, pocket depth and attachment levels in adults over 18 years of age with no systematic diseases. They excluded studies evaluating CHX with sodium fluoride, sprays, gels, dentifrices or other non-mouthrinse formulations. The authors assessed quality and risk of bias at the study level and rated those based on five criteria.
The authors identified eight studies (803 patients). Two studies used two different brand name formulations of chlorhexidine; therefore, 10 sets of data were included. Eight studies provided data on plaque inhibition, three on bleeding, one on gingivitis and none for probing depth or attachment level. Six studies demonstrated a low risk of bias, and two exhibited moderate risk. All patients underwent a thorough supragingival scaling and polishing before the study, and seven studies instructed participants to only use CHX for their oral hygiene measures. Four types of indices were utilized to assess plaque score and bleeding, and two for gingivitis. The authors conducted a meta-analysis for plaque index (Quigley & Hein). They reported a statistically significant difference for plaque accumulation with a weighted mean difference of 0.10 (95 percent CI, 0.03 to 0.17) in favor of the 0.2 percent concentration. The effects of alcohol-free CHX and the effects on perturbation of taste perception are unclear; however, 30 seconds of rinsing may be just as effective as 60 seconds.
This systematic review provides evidence for the difference in the beneficial effects of 0.2 percent compared to 0.12 percent CHX on plaque accumulation. This small statistical difference may not translate into clinical benefits and is probably negligible. Three studies evaluating the effects on gingivitis were unable to show any differences on inflammation.
Source of Funding:
Importance and Context:
Many patients are unable to maintain their oral hygiene status by mechanical methods (brushing and flossing) alone.(1) Chlorhexidine has been shown to reduce the number of bacteria on mucosal surfaces (1,2) and within the gingival sulcus or pocket. (1) On the other hand, CHX has the potential to alter taste perception and cause extensive staining of the teeth.(3) Evidence providing information that a lower concentration of CHX is equally as effective compared to higher concentrations may improve patient compliance and lessen adverse effects.
Strengths and Weaknesses of the Systematic Review:
The strengths of this review consisted of: a comprehensive search strategy; a well-defined clinical question with appropriate inclusion and exclusion criteria; quality assessment measures for risk of bias and heterogeneity of the included studies; and meta-analyses techniques applied appropriately. Weaknesses consisted of: only searching the published, English-language literature; and unclear search date and data extraction protocol. Publication bias cannot be ruled out, as additional studies may have been located by expanding the search methodology.
Strengths and Weaknesses of the Evidence:
The main strength of the review's evidence was the consistent utilization of one plaque index (Quigley & Hein) for six studies, making it possible to pool the data by meta-analysis. The weaknesses consisted of: insufficient literature for answering the clinical question posed by the authors for determining the effects on bleeding (three studies), gingivitis (one study), and pocket depth or attachment levels (0 studies); the use of different indices for assessing bleeding and gingivitis; and variations in rinse volume and follow-up periods for the included studies, which may have affected the overall results. Consistent follow-up is important for assessing whether beneficial short-term effects are sustainable. For an additional viewpoint on this systematic review, refer to the commentary by Dr. Debora Mathews (4), which presents a similar conclusion.
Implications for Dental Practice:
The use of adjuvants for controlling disease is not new to dentistry, and mouthrinses are frequently recommended to patients in clinical practice. When prescribing the 0.2 percent concentration, the clinician should weigh the marginal benefits against the possibility of an increase in adverse effects.
1. Barnett ML. The rationale for the daily use of an antimicrobial mouthrinse. J Am Dent Assoc. 2006;137 Suppl:16S-21S.
2. Lamster IB. Antimicrobial mouthrinses and the management of periodontal diseases. Introduction to the supplement. J Am Dent Assoc. 2006;137 Suppl:5S-9S.
3. McCoy LC, Wehler CJ, Rich SE, et al. Adverse events associated with chlorhexidine use: results from the Department of Veterans Affairs Dental Diabetes Study. J Am Dent Assoc. 2008;139(2):178-183.
4. Matthews D. No difference between 0.12% and 0.2% chlorhexidine mouthrinse on reduction of gingivitis. Evid Based Dent. 2011;12(1):8-9.