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Clinical reduction of S. mutans in pre-school children using a novel liquorice root extract lollipop: a pilot study


AIM: To determine the clinical effect of a simple herbal caries-prevention protocol aimed at reduction of Streptococcus mutans (SM) in young children in a pre-school setting. STUDY DESIGN: Proof-of-principle pilot study. METHODS: To prove the concept this pilot study delivered a clinical intervention using sugar-free lollipops containing liquorice root extract. Regimen: Supervised herbal lollipops, twice daily for 3 weeks. Species-specific monoclonal antibody testing of saliva provided SM counts. Children were grouped in high, medium and low caries-risk using baseline SM-levels as risk-indicator. Bacterial numbers at baseline, during intervention, and for 9 weeks post-intervention were compared. STATISTICS: SM levels were analysed using GEE modelling. RESULTS: High-risk children showed the steepest early decrease in mean log-SM (P<. 001). At end of a follow-up period, the log-SM decrease moved the high-risk group down to moderate-risk level. High-risk children showed a decrease in fitted mean SM% not seen in other groups (P<. 001). The decrease reached a nadir around 22-days post-intervention. Twice-daily use of herbal lollipop significantly reduced both number and relative percent of SM in high-risk children. SM numbers were reduced for 22 days after the last lollipop, stabilized and then began to rebound. CONCLUSION: A potential for simple effective caries-prevention for high-risk children has been demonstrated. Encouraging results warrant randomised clinical trials (RCT) of liquorice root in herbal lollipops or alternative modes of delivery.

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Correspondence to M. C. Peters.

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Peters, M.C., Tallman, J.A., Braun, T.M. et al. Clinical reduction of S. mutans in pre-school children using a novel liquorice root extract lollipop: a pilot study. Eur Arch Paediatr Dent 11, 274–278 (2010).

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Key words

  • Streptococcus mutans
  • antibacterial agent
  • dental caries
  • early childhood caries