A comparative effectiveness research (CER) synthesis of two Cochrane systematic reviews on the effects of interventions in treating halitosis

• Ano de defesa: 2016
• Autor(a) principal: Fedorowicz, Zbigniew
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Comparative effectiveness research; Halitose; Halitosis; Higienização de língua; Pesquisa comparativa de efetividade; Revisão sistemática; Systematic review; Tongue cleaning; Tongue scraping; Tratamento; Treatment
• Link de acesso: http://www.teses.usp.br/teses/disponiveis/58/58131/tde-15092016-150431/

The aim of this research was to perform a Comparative Effectiveness Research (CER) synthesis of two Cochrane systematic reviews on the effects of interventions in treating halitosis and to evaluate the rigour in their conduct and methodological quality using a validated tool that has been developed specifically for the assessment of multiple systematic reviews (AMSTAR). Methods: Electronic databases were searched from their inception to 2005 and further updated to February 2009. These searches retrieved 990 citations, which after assessment for relevance left 20 potentially eligible studies. Independent and duplicate application of the inclusion criteria excluded all but 7 of these reports from further review. The reference lists were handsearched to ensure that no trials had been missed. Results: A total of seven trials were identified. Two provided some weak and unreliable evidence for the use of tongue scraping as a means of controlling halitosis. Reduction of volatile sulphur compounds (VSC) levels in one trial was short lived and the other showed a small amount of tongue trauma induced by 1 week of tongue scraping. Five trials provided data for the mouthrinses: 0.05% chlorhexidine + 0.05% cetylpyridinium chloride + 0.14% zinc lactate mouthrinse significantly reduced the mean change (standard deviation (SD)) of organoleptic scores from baseline compared to placebo (-1.13 (1.1) P < 0.005 versus -0.2 (0.7)) and also caused a more significant reduction in the mean change (SD) in peak level of VSC (-120 (92) parts per billion (ppb) versus 8 (145) ppb in placebo). Chlorhexidine cetylpyridinium chloride zinc lactate mouthrinse showed significantly more tongue (P < 0.001) and tooth (P < 0.002) staining compared to placebo. Assessment of the methodological quality of the systematic reviews based on the 11-item AMSTAR tool confirmed their high quality. Conclusions: This comparative effectiveness research synthesis has illustrated the short-lived effect of tongue scraping on reducing VSC levels and that the potential for adverse effects with their long-term use should be off set against the possibly limited duration of their benefits in VSC reduction. It also highlighted the diversity in effectiveness of some of the more popular over the counter mouthrinses in treating halitosis. Antibacterial mouthrinses such as chlorhexidine or cetylpyridinium chloride can reduce bacterial levels on the tongue but the effectiveness of chlorine dioxide and zinc containing mouthrinses in neutralisation of odoriferous sulphur compounds should not be underestimated. There would therefore appear to be a place in the management strategy of halitosis for formulations, which include and combine some of these constituents. Following one of the fundamental principles of the Cochrane Systematic Reviews, this work was updated in April 2014 and only one of the chosen studies met the inclusion criteria, but added no new information that would alter the conclusions of this thesis. Further well-constructed randomized controlled trials, which comply with CONSORT, are necessary and future research should explore outcomes that are both relevant and patient-preferred and should aim to provide evidence for people to make informed decisions whether these treatments are effective.