Current concepts of caries etiology
Pathogenesis of caries
Physical properties of foods and cariogenicity
Individual components effects on DC
Calcium and Phosphorus.
Studies providing evidence for relationship between diet in
Non interventional studies
Special group population
Assessment of cariogenic potential of food stuff
Sugar substitute and alternative sweeteners
Dietary screening and education in the dental practice
Aristotle- “ why do figs, when they are
soft and sweet , produce damage to the teeth?”
Miller’s – Contribution of micro flora in
fermentation process and linked - diet
In 1930 : Voluminous literature .
Is a progressive irreversible microbial disease affecting
the hard parts of the tooth exposed to the oral
environment, characterized by demineralization of
inorganic substance followed by dissolution of organic
constituents leading to the formation of a cavity
Is a microbial disease of the calcified tissues of the teeth
characterized by demineralization of the inorganic portion
& destruction of organic substance of the tooth.
That which is taken in and absorbed for the growth and repair
Encompasses every thing that is eaten, regardless of its
nutritional value and regardless of its fate in the digestive
Deals with those elements of the diet that are absorbed from the
intestinal tract and enter into the metabolic processes of the
External (environmental factors)
Internal (endogenous factors)
SUBSTRATE OR DIET
ENAMEL PELLICLE + BACTERIA
PLAQUE BACTERIA + FERMENTABLE CARBOHYDRATE
DEMINERALISATION AND DISSOLUTION OF INORGANIC
AND ORGANIC STRUCTURES OF TOOTH
Cohesion: tendency of food to stick itself
Adhesion: pressure applied to food – interproximal and
occlusal sites : masticatory stress
Adhesiveness: firm attachment between the food and the
Tackiness : ability of food to stick to the tooth when
minimal force is involved
Effects of Carbohydrates.
Effects of Proteins.
Effects of fats.
Effects of Vitamins.
Effects of Calcium and Phosphorus.
Effects of Trace elements
TYPES OF SUGARS AND USES
CLASSIFICATION OF SUGARS
SUCROSE A UNIQUE SUBSTRATE FOR
FACTORS AFFECTING CARIOGENECITY OF
SUCROSE IN DIET
STARCHES AND DENTAL CARIES
Types of sugar
Raw sugar , Turbinado sugar ,White granulated refined sugar,
Corn syrup , Honey
Sugar manufacture’s :
Pure invert sugar.
Common invert sugar
Uses of sugars :
Flavor blender and modifier
Texture and bodying agent
Dispersing/ lubricating agent.
Smooth surface caries- biochemical grounds
depends on growth of dental plaque
St. Mutans - Synthesize dextrans /glucans and levans.
Glucans: insoluble ,serve as structural Components of the
plaque matrix- gluing certain bacteria to the tooth
Levans – soluble, serve as transient reserves of
fermentable carbohydrates- prolonging duration of
Polysaccharide built: glucose units are transferred from
sucrose to the active sites of enzyme- to growing chain
Enzymes : Sugar 1- phosphate, nucleosidediphosphate- sugar:
transfer glucose/ fructose units directly to growing polymer.
Enzymes conserves: high energy( dihemiacetals) btn two C1 of
glucose and C2 of fructose ( 6600Cal/ Mol)
Streptococcus sanguis and S.mutans:
Glucosyl 1- transferases- Paque matrix material
Fructosyl transferses- Organic acids.
Highly specific for sucrose
optimum 5.2 to 7 coinciding with pH
Sucrose is not required : formation of above enzymes
Frequency of eating
Effective concentration of Sucrose
Cannot directly serve as substrate .
Two varieties of Starch – Cooked Starches and Uncooked
Cooked Starches Ex : Rice , Potatoes and Bread -cariogenic.
Uncooked Starches – Virtually non cariogenic.
Untreated Starchy foods – Lower caries promoting potential.
Addition of sugars – Increases cariogenicity.
Less refined Starchy foods – Protect teeth.
Gross protein deficiencies are rare
Adding of Casein to diet – Significantly less caries
Amount and quality of protein – Important factors.
Ayad et al 2000 – There is no direct evidence.
Williams et al 1982 – Certain fatty acids , antimicrobial
Deficiency of essential fatty acids in man – rare.
Oleic and lenolic fatty acids – bactericidal activity.
Oleic acid – protection against decalcification.
Cheese – Remineralization and Neutralizes acids.
The mechanisms whereby fats act to reduce dental caries.
Coating of tooth surface with a oily substance.
Prevent fermentable sugar from being reduced to acids.
May interfere with the growth of cariogenic bacteria.
Increased dietary fat – Decrease the amount of dietary
Vitamin D :
Many authors have suggested the synergistic action of
malnutrition and infection as the most probable causative
factor (Sweeney et al 1971).
Hypocalcemia a Specific Cause of Enamel
Recently evidence has suggested that the etiology of enamel
hypoplasia is highly specific and linked with disorder of
calcium homeostasis (Nikiforuk et al 1979).
Mellanby (1936) reported that there was a strong correlation
between hypoplasia in the teeth of British School children and
Several other surveys have supported this conclusion (Allen,
1941, Bibby 1943, Care 1953).
The prevalence of enamel hypoplasia and dental caries is
higher in prematurely born children than in controls
(Rosenweig et al 1962).
Other Vitamins and Dental Caries
Vitamin K (2-methyl-1,4-naphthoquinone)
Burrill and associates (1945)
Vitamin B complex
Gustafson et al 1963 – Level of calcium in the diet is a
Phosphate – Locally Cariostatic.
Local effect P+ is due to :
Reduce the rate of dissolution
Buffer organic acids
HOPEHOOD HOUSE STUDY
TURKU SUGAR STUDY
NON INTERVENTIONAL STUDIES
CROSS- SECTIONAL STUDIES
Vipeholm study Sweden (1945- 1954):
Mental institution at the Vipeholm hospital near Lund,
Purpose- to determine the effects of frequency and
quantity of sugar intake on the formation of caries.
Conclusion : physical form of carbohydrate ( stickiness,
oral clearance time, frequency of intake) much more
important in carcinogenicity than the total amount .
Increase in caries activity due to..
Increased carbohydrate intake
sugars retained on the surfaces of teeth
Consumed between the meals
Varies between the individual
Withdrawal of sugar – caries activity rapidly disappears
Prolonged retention of high concentration sugar in
Clearance time of the sugar
1942, 80 children, 7-14 yrs (10yr period)
Vegetarian diet- largely raw
Absence of meat and rigid restriction of refined carbohydrate
Caries reduced to a minimal level by dietary means alone in
spite of unfavorable hygiene and fluoride levels
Dental caries prevalence in young children almost negligible
in primary dentition and approx. 1/10 that seen in the
permanent teeth of Australian child
Seventh Day Adventist dietary counsels advise limitation of
use of sugar, sticky desserts, highly refined starches, and
between- meal snacking
Adventist children tends to be lower than that in non-
Adventist children in same geographic location and
In Turku, Finland, by Scheinin, Makinen, etal
Aim: To test the effects of chronic consumption of sucrose,
fructose, and xylitol on dental and general health. (1972-
Basis : Xylitol is a sweet substance not metabolized by plaque
Investigated by comprehensive program including clinical
radio graphical biochemical and micro biochemical,
determinants of health
Caries reduction -after 2 years of xylitiol consumption:
Fructose was as cariogenic as sucrose for first 12 months but
became less at the end of 24 months
Chewing of a xylitol gum produced an anticariogenic effect- in
Subjects are free to choose whatever diet they please,
correlation bet caries increment and dietary factor is low.
Based on dietary recall
No control over amount/ frequency of sugar intake
Before world war II estimated sugar consumption rate
15 kg/person/ year-reduced to less than 0.2 kg/person/year
Dental caries rate dropped during war time and rose when
sugar restriction were lifted -England, Norway and Japan
Jacobi – relation between practice of feeding infants sucrose-
containing beverages and milk at bedtime
Added sugar or sugar dipped pacifier at bed time – (Fass)
At will breast feeding – primary dentition in infants
7.2 % lactose by weight in human milk: 4.5 % in bovine milk
Sugar coated – highly cariogenic
Eating sucrose during meal time as part of a diet does not
increase dental caries -swallowed before the sweetness is
extracted -increased salivation during meal time removes
Buffering capacity of milk proteins or high phosphate content
According to Shaw…..1 ounce /day
total consumption- 2 pounds/week
Nature provided subjects – strict dietary pattern
First noticed at weaning---- (1956)
AR disorder of fructose metabolism
Reduced levels of fructose-1- phosphate
Avoid any food that contains fructose or sucrose
If ingested – nausea, vomiting, malaise, tremor, excessive,
sweating, and even coma ( fuctosemia)
Most of the symptoms due to secondary hypoglycemia
Comfortable with other foods containing glucose, galactose,
Dental caries prevalence of these subjects – extremely low
Highly significant differences in the proportion of
Streptococcus mutans and Lactobacillus
Low prevalence of caries indicates- starchy food per se do not
produce decay , where as sugary foods do
Observation also emphasize that plaque micro flora is directly
influenced by the type of dietary sugar ingested
Bakeries – air polluted with sugar dust exceed 200 mg/m3
workers consume relative large amounts of sugar----- textile
Chocolate factory ----- employees at a shipyard
Sugar cane cutters (macheteros) habitually chew raw sugar
and consume large quantities of raw sugar cane juice
(guarapo)---- textile workers
These Habits illustrate the fact the raw sugar can be
as deleterious to dental health as refined sugar
METHODS TO MEASURE THE CARIOGENIC POTENTIAL
In vitro caries models
In vivo/ In vitro caries models
Adhesiveness of foods
Plaque PH measurements
Food consumption and dietary habits – favorable and
Influence the type and proportions of specific cariogenic
microorganisms found in the dental plaque
Sequence of eating pattern
Ideal test: should include host and micro flora as well as
substrate- combination of tests
Currently accepting methods: pH
measurements and animal
testing ( control –sucrose)
No cariogenic potential: do not lower plaque pH
Low cariogenic potential: causes less than 40% of the
High cariogenic potential: similar to positive control group
Large group fall into an intermediate category between low
and high – becos of overlap of standard deviation
Food is mixed with an inoculum of salivary flora- amount of acid
Adhesiveness of food
Production of titratable acid an artificial mouth
Remote from the real life.
Salivary flora is not representative of the plaque microbes
Two tests, ICT and IPT
Intraoral Caries Test – Enamel hardness.
Iodine Permeability Test – Permeability.
Bovine enamel block mounted on the prosthesis – worn intraorally
Limitation – Food only in solution and
plaque is removed from the teeth at intervals after ingestion of
the test food
limitations: plaque is disturbed
pooling of different sites
measurements is intermittent
Microelectrodes placed with in plaque on the tooth surface at
intervals after food ingestion
Direct reading of pH
Antimony and glass electrode-
Disrupts the plaque structure
Outer surface of plaque pH
Miniature electrode built in to prosthesis
readings taken continuously by either wire or radio telemetry
Previously glass electrode- slow response(30 sec)
Hydrogen ion sensitive field transistor
Extremely small : 1mm2
Low electric resistance
Rapid response time (10sec)
Indwelling bimetallic ( palladium/ palladium oxide)- versatile
Pattern and sequence of food intake – influence plaque pH
used in small no. of persons
Permutations of sequence and frequency intake -
Swiss Office of Health
below 5.7 during and up to 30 min
“Safe for teeth” or Zahnschonend
Labeling the product: non cariogenic (nicht kariogen)
Most important role :Sugar free confectionery, chewing gums
soft drinks, table top sweeteners and in liquid oral medicines.
Non sugar sweeteners :
1. Bulk sweeteners or Caloric sweeteners.
Ex: Polyalcohol (Sorbitol , Xylitol), Starch hydrylsates
2. Intense sweeteners or Non caloric sweeteners.
Ex: Aspartams, Saccharine, Cyclamate, Some Plant
Bulk sweeteners :
Chemically similar to sugars.
Add volume and sweetness to a product.
0.5 to 1.0 times as sweet as sucrose.
Have an energy value ( Kilocalories ).
Naturally found in foods.
Prepared from glucose by hydrogenation.
One half as sweet as sucrose .
Slowly and incompletely absorbed from the intestine : result
in osmotic diarrhoea.
Microbial Metabolism of Sorbitol.
Most oral microorganisms lack the enzymatic makeup to
Absorption slow and incomplete .
Used in Diabetics.
Metabolism by Oral Microorganisms :Human oral
microorganisms do not have enzymes to utilize xylitol.
Lycasin :Hydrogenated glucose syrup produced from starches
Caloric value – Similar to other carbohydrates.
Not chemically related to sugars.
Added in very small quantities and not volume.
100 to 1000 times sweeter than sucrose.
Negligible energy value ( Kilocalories )
Low caloric sweeteners are used in:
Gelatin desserts puddings
Dentifrices and mouth washes
180-200 times as sweet as sucrose.
Composed 2 amino acids : L-aspartic acid and
Methyl ester of L-phenylalanine.
Reduces caries – Limiting the amount or frequency of
fermentable sugar in the diet.
Pharmacologically inert and is stable.
Widely used in – diets , soft drinks , dietic food , mouth
medicinal preparations , sweeteners for table use.
Organic sweetener .
Other sweeteners derived from plant sources
500-3000 times as sweet as sucrose.
Ex: Monelin, Licorice, Dihydrochalcone, Miraculin
Sugar Substitutes in Pharmaceutical Preparations
Xylitol, Mannitol , Sorbitol , Lycasin.
May decrease the local caries challenge or conversely
enhance the local natural defense mechanisms .
Ex : Presence of Ca and P in Saliva.
Routinely screen patients.
Assessment of determinants of dietary intake
Behaviors that associate with dental health and caries risk
Screening - Two parts
Part – A
Part – B
Restrict the number of eating times to three main meals.
Avoid carbohydrate ( sugars ) snacks in between meals.
Take low carbohydrate and high protein snacks and fibrous
fruits in between meals, if required.
Eliminate eating sticky sweets like chocolates, toffees,
candles, cake, and pastries, if not completely then as much as
Increase eating of high protein food like meat, fish, milk, egg,
pulses and beans.
Restrict carbohydrate eating so that they only provide between
30 to 50 percent of total calories requirement of the body.
Eat firm detersive food like raw vegetables and fruits which
will reduce dental plaque formation and increase salivary
If present ,Free sugars – 15 to 20 Kg/person/year
( 40-55 g/day ).
If Absent, Free sugars – below 15Kg/person/year
Dentistry for Child & Adolescent – Mc Donald 8th
Newbrun, Cariology 1stEdition.
Rugg- gun ,Diet Nutrition and Dental Caries. 1st Edition.
Per Axelsson- diagnosis and risk prediction of dental caries
Essentials of preventive and community dentistry, 2nd