BEVERAGE EFFECTS ON
HUMAN TOOTH ENAMEL
Frankie Vozza
Central Catholic High School
Grade 9
February 6,2010
PROBLEM
Does the prolonged exposure of human teeth
in a beverage effect the thickness of enamel?
DENTAL PRINCIPLES
The profession of diagnosing and treating
conditions that occur in the tissues of the
mouth
Necessary for complete overall health
THE HUMAN TOOTH
TOOTH ANATOMY: ENAMEL
Hardest and most mineralized substance of
the body.
96 % percent mineral with 4% water and
other organic material
Often up to 3.1 millimeters thick
TOOTH ANATOMY-DENTIN
One of the four major components of teeth
Covered by the enamel and surrounds the
entire pulp.
Less mineralized than enamel
Necessary for the support of enamel.
70% percent of mineral, 20% percent
organic material and 10% percent water.
TOOTH ANATOMY- PULP
Softest part of the tooth
Lies in the root and extends all of the way
to the top part of the tooth
The pulp contains: blood vessels, nerves,
and connective tissue
Essential for supplying the tooth with
nutrients and sensation.
TOOTH ANATOMY- NERVE
Contained in the pulp of the tooth.
Send signals to the brain that convey where
the teeth are in the mouth (If the mouth is
open or closed).
Supplies sensation of pain
TOOTH ANATOMY
PERIODONTAL LIGAMENT
Specialized tissues that attach the tooth to the
bone
Acts as guard in which it detects the forces
being placed on the teeth
Supporting tissue and is about 0.2 millimeters
in width
Breakdown of Enamel
 Occurs within the deep grooves, pits, and
fissures of enamel.
 These locations are impossible to reach with a
toothbrush and allow for bacteria to reside
 Leads to the demineralization of enamel
Breakdown of Enamel
 Sugars from candies, soft drinks,
and juices play a significant role
in tooth decay.
 pH in the mouth initially
decreases from the ingestion of
sugars
 Enamel is demineralized and
left vulnerable for about 30
minutes.
 Enamel begins to demineralize
and eventually the acid eats
away into the thickness of the
enamel
ACIDITY OF
USED
BEVERAGES
pH scale: a range
of values that are
used to express
acidity or basicity
of a solution.
Describes a
solution in which is
lower than 7 is
acidic and higher
than 7 is basic. ( 7
is neutral)
Beverage
Acidity Level
(Ph scale)
Coke Classic
2.53
Milk, 2%
6.8
Orange Juice
3.30-4.15
Tap Water
4.0-7.0
Pure Water
7.0
PURPOSE/OBJECTIVE
To determine if the
prolonged exposure to a
beverage has an effect on
tooth enamel.
Null Hypothesis
Prolonged exposure of enamel in
tested beverages will not significantly
reduce enamel thickness.
Alternative Hypothesis
Prolonged exposure of enamel in tested
beverages will cause significant reduction
in enamel thickness.
MATERIALS
1.Perioprobe
2. Dissecting Microscope
3. Experimental liquids ( 2% milk ,Coke
Classic , orange juice, Tap water, distilled
water)
4. Extracted and sterilized human teeth
5. Lab Materials (Plaster mixing
equipment)
PROCEDURE
1.
Observed and recorded initial thickness of enamel
2.
Precisely measured the amount of pure water to be put into
plastic container with graduated cylinder (1 liter)
3.
Sterilized the extracted teeth and visually examined, making
sure no defects were present.
4.
Mounted four teeth in each plaster trough.
5.
Placed the teeth inside the plastic container completely
submerged in liquid.
7.
Let the teeth soak in pure water for twelve hours nonstop then
removed teeth from liquid environment for 12 hours.
8.
Repeated Step 6 for Four weeks daily.
8.
After four weeks, teeth were removed and rinsed
thoroughly.
9.
Teeth were then sectioned with a diamond toothed cutting
bur by dental student at Univ. of Pittsburgh Dental School.
10.
Used a perioprobe (dental instrument) to measure the
thickness of enamel at cusp tips using dissecting
microscope provided by CCHS.
11.
Recorded the data in a Record Book and computed
averages.
12.
Made general visual and tactile observations and recorded
findings.
13.
Repeated Steps 5-12 with each set of mounted teeth in
their respective experimental liquid ( 2%Milk, Classic
Coke, Orange Juice, Tap water).
14.
Compared data charts together and analyzed results,
making comparisons of enamel thickness measurements.
INITIAL ENAMEL THICKNESS
Beverage Trial 1
Trial 2
Trial 3
Trial 4
Average
Water
3.0
3.0
3.1
2.9
3.0
Orange
Juice
3.0
2.9
2.8
3.0
2.925
2% Milk
3.0
2.8
3.1
2.8
2.925
Tap Water
2.9
3.0
2.9
2.8
2.90
Classic
Coke
3.0
2.8
3.1
2.8
2.95
Table 1. Thickness Recorded with perioprobe
Final Enamel Thickness
Beverage
Trial 1
Trial 2
Trial 3
Trial 4
Average
Water
3.0
3.0
3.1
2.9
3
Orange
Juice
2.75
2.50
2.4
2.7
2% Milk
3.0
2.4
2.7
2.5
Tap Water
2.75
3.0
2.9
2.4
2.7625 No observable change
Classic
Coke
2.7
2.3
2.6
2.2
2.525
Observations
No observable change
2.5625 Teeth appeared more
translucent than control
2.65
No observable change
Dark brown color
extended deep into tooth
with soft outer surface
Table 2. Thicknesses of Enamel measured under dissecting microscope
and general observations.
Percent Change Between
Initial and Final Enamel
Thickness
Beverage
Trial 1
Trial 2
Trial 3
Trial 4
Average
Changed
Orange
Juice
8.33%
16.66%
14.28%
13.33%
13.15%
2% Milk
0%
14.28%
14.81%
10.71%%
9.95%
Tap Water
5.17%
3.44%
3.57%
14.28%
6.61%%
Coke
Classic
11.11%
17.85%
16.12%
21.42%
16.625%
Percent changed by millimeters
DECREASE OF ENAMEL THICKNESS
0.45
P= 0.001601
Enamel Thickness Changed
0.4
0.35
0.3
Average
changed
0.25
0.2
0.15
0.1
0.05
0
Water
Orange
Juice
Milk
Tap Water
Tested Beverages
Pop
ANOVA
Analysis of variance
Anova: Single Factor
SUMMARY
Groups
Statistical test comparing
variation within and
between experimental
groups
Count
Sum
Average
Variance
Column 1
4
0
0
0
Column 2
4
1.45
0.3625
0.005625
Column 3
4
1.1
0.275
0.035833
Column 4
4
0.55
0.1375
0.035625
Column 5
4
1.9
0.475
0.015833
ANOVA
If the P-value is lower
than the value (.05), then
the result is significant ( a
result of the variable
influence )
Source of
Variation
SS
df
MS
Between
Groups
0.55625
4
0.139063
Within
Groups
0.27875
15
0.018583
0.835
19
Total
F
7.483184
P-value
0.001601
F crit
3.055568
ENAMEL THICKNESS DUNNETT’S TEST
T- CRITICAL= 3.70
Beverage
T-Value
Interpretation
Orange Juice
1.75
Not Significant
2% Milk
1.42
Not Significant
Tap Water
.71
Not Significant
Coke Classic
2.46
Not Significant
CONCLUSIONS

Rejected the alternative and accepted the null
hypothesis

No significant difference in enamel thickness

Liquids alone cannot cause teeth to decay.

Demineralization did occur but the enamel did not
breakdown.
LIMITATIONS, EXTENSIONS,
AND FUTURE STUDIES
Limitations
Decay
did not exactly occur because chemical,
pathological, and mechanical factors were not all
present.
Not
all teeth were identical.
Extensions, and Future Studies
Larger groups of teeth will be employed in the
next series of testing.

Mechanical
Different
breakdown will also be a factor
acidic beverages will be tested
BIBLIOGRAPHY
Bauman,
Robert W. Microbiology with Diseases by
Taxonomy (2nd Edition) (The Microbiology Place Series).
San Francisco: Benjamin Cummings, 2006. Print.
Roberson,
Theodore. Sturdevant's Art & Science of
Operative Dentistry. Chicago: Mosby-Year Book, 2001.
Print.
Myers,
P., R. Espinosa, C. S. Parr, T. Jones, G. S.
Hammond, and T. A. Dewey. 2006. The Animal Diversity
Web (online). Accessed January 29, 2010 at
http://animaldiversity.org.
http://www.webmd.com/oral-health/tc/tooth-decay-topicoverview