Enamel protection from acid challenge--benefits of marketed fluoride dentifrices.

OBJECTIVE: To determine the ability of various marketed dentifrices containing stabilized stannous fluoride (SnF2), sodium fluoride (NaF), or sodium monofluorophosphate (SMFP) to protect enamel against the earliest stages of erosive dietary acid damage using an in vitro enamel protection model. METHODS: Acid-challenged, extracted human teeth were treated with a 1:3 dilution of dentifrice, rinsed, and then challenged in a controlled series of tests using four dietary acids considered potentially erosive to teeth. Each acid was collected and analyzed to determine the level of mineral (phosphorous) removed from the teeth during the challenge. Post-treatment results were compared to baseline values for each acid. Results for the four acids were averaged and reported as an average percent protection value for each of the dentifrices tested, with higher values representing greater acid protection. The study included six dentifrices formulated with (A) sodium fluoride (NaF), (B) stabilized stannous fluoride (SnF2), (C,D) NaF plus 5% potassium nitrate (KNO3), (E) sodium monofluorophosphate (SMFP), or (F) SMFP plus 8% arginine bicarbonate. RESULTS: The stabilized SnF2 dentifrice demonstrated an average protection score of 39.3%, while products formulated with NaF resulted in protection scores between 11 and 13%. The SMFP dentifrice was rated at -3.5%, and the SMFP + arginine bicarbonate dentifrice resulted in a net average score of -5.0%. Results of this test were statistically significant (p < 0.05, ANOVA: B > A = C = D > E = F), in favor of the stabilized SnF2 dentifrice. CONCLUSIONS: These results suggest the stabilized SnF2 dentifrice has the potential to provide significantly better overall acid protection versus any of the other dentifrices included in the study.

The protective effects of toothpaste against erosion by orange juice: studies in situ and in vitro.

OBJECTIVES: There has been a monumental increase in the consumption of soft drinks, fruit juices and sport drinks in the UK, the US, and many other countries. Previous investigations have demonstrated the erosive nature of these acidic soft drinks. The aim of this investigation was to determine the protective effects of an experimental fluoride-based toothpaste, containing sodium hexametaphosphate, against an erosive challenge on tooth enamel. METHODS: The erosion of enamel by orange juice compared the experimental toothpaste with a benchmark sodium fluoride paste and negative control, water, in a 15-day in situ model; and the same in an in vitro enamel erosion model. Flat, polished human enamel samples with a surface profile of +/-0.1mum, were exposed to the three regimens in the single blind, crossover clinical study mimicked in vitro. Depths of the resulting eroded areas were measured using a profilometer. RESULTS: There was significantly more erosive damage on the specimens exposed to the benchmark paste and water compared to the test paste in both the in situ and in vitro studies. CONCLUSIONS: The data provide further support for tooth brushing before meals. Results of this study further suggest the sodium hexametaphosphate containing paste could be used to provide significant erosion protection in susceptible individuals over that provided by conventional fluoride products.