This document summarizes a study that evaluated the effects of 5 commercial mouthrinses containing 0-450ppm fluoride on enamel erosion using an in vitro model. Bovine teeth were prepared as specimens which were treated with the different mouthrinses and underwent cycles of citric acid erosion and artificial saliva remineralization over 5 days. The results showed that treatment with the mouthrinse containing 450ppm fluoride (Rinse E) elicited the lowest enamel erosion depths and least tissue loss compared to the other rinses tested. Higher fluoride concentration in the mouthrinses was found to provide better protection against enamel erosion in this simulated model.
2. Dental erosion is one of the most
common causes of tooth surface loss
The early stage of enamel erosion, where
demineralisation causes a reduction in mineral density
but no bulk tissue loss occurs, is reversible as the lost
mineral ions can be replaced by those naturally
present in saliva.
demineralisation process is unchecked or particularly
aggressive, the enamel scaffold is lost completely and
bulk tissue loss, which is irreversible, results.
3. objectives
commercial mouthrinses containing
0−450ppm fluoride on erosion progression in
enamel using a simulated 5-day in vitro
cycling model with concurrent monitoring of
surface microhardness (SMH) and bulk tissue
loss.
4. ‘preparation of enamel specimens’
Bovine teeth were obtained in accordance with
current local legislation from slaughtered cattle of
single stock aged ~30 months.
Cylindrical cores 7mm in diameter were drilled out
of bovine incisors using a Bosch Universal
Professional Plus Diamond Core drill.
5. ‘preparation of enamel specimens’
The resulting specimens, containing enamel of
~3mm depth, were mounted in acrylic resin, cured
overnight, and both sides polished flat using
wetted 1200 silicon carbide grit paper using an
Ecomet® 250 GrinderPolisher
The exposed enamel was further polished with
wetted 2500 silicon carbide (SiC) grit paper,
followed by diamond polishing usingTexmet® 1500
cloth (Buehler,D¨usseldor
6. ‘preparation of enamel specimens’
Specimens were subsequently rinsed thoroughly
with tap water from a non-fluoridated supply, and
stored in a humidified atmosphere at 4ºC.
Immediately prior to use,an erosion window was
created on the specimen using Cello tape
7. ‘prevention of enamel surface softening’
Topical application of fluoride should be a
preferred strategy owing to its ease of use and its
proven efficacy in prevention of enamel
demineralization.
8.
9. The five mouthrinses purchased
for this study were as follows: Rinse A: Listerine®
Original (Johnson & Johnson, Maidenhead, Berkshire,
UK); Rinse B: Scope® Original Mint (Procter & Gamble,
Cincinnati, OH, USA); Rinse C: Colgate® Plax Cool Mint
(Colgate Palmolive, Guildford, Surrey, UK); Rinse D:
Aquafresh® ExtraFreshDailyMildMint(GlaxoSmithKline
ConsumerHealthcare,Brentford,Middlesex,UK);RinseE:
Sensodyne® Pronamel® Daily Mouthwash
(GlaxoSmithKline
Consumer Healthcare,Brentford,Middlesex,UK).
10.
11. Each cycle comprised immersion of each
group of specimens in 1.0% citric acid
monohydrate pH3.2 (200mL, 5min, 27ºC,
50rpm) followed by artificial saliva pH7.0
(200mL, 120min, 35ºC, 20rpm).
12.
13.
14. This effect was most marked in the specimen
group treated with Rinse E where the mean lesion
depth was directionally lowest at every
measurement point throughout the study
Treatment with Rinse E, containing 450ppm
fluoride, elicited numerically lower mean erosion
depths compared to all other rinses at all time
points, with differences in in vitro efficacy
statistically significant from day 3 onward.
Bulk tissue loss of enamel in the present
simulated 5-day in vitro cycling erosion model is
inversely proportional to the fluoride
concentration of the rinse treatment