Transcript No Slide Title

CARIES RISK GUIDELINES
(American Dental Association 1996)
LOW:
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No carious lesions in last year
Coalesced or sealed pits and fissures
Relatively plaque free
Fluoride in water supply and use of fluoride
dentifrice
• Regular dental visits
CARIES PREVENTION MODALITIES
FOR CHILDREN BY RISK CATEGORY
(American Dental Association, 1996)
LOW
• Educational reinforcement:
– Plaque removal (oral physiotherapy)
– Fluoride dentifrice
– One year recall
CARIES RISK GUIDELINES
(American Dental Association, 1996)
MODERATE
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One carious lesion in the last year
Deep pits and fissures
Some plaque accumulation
No fluoride in water
White spot lesions
Irregular dental visits
Orthodontic treatment
CARIES PREVENTION MODALITIES
FOR CHILDREN BY RISK CATEGORY
(American Dental Association, 1996)
MODERATE
• Pit and Fissure Caries
– Sealants
• Smooth Surface Caries
– Education
– Dietary Counseling
– Fluoride dentifrice (low potency fluoride)
– Fluoride mouthrinse (low potency fluoride)
– Professional topical fluoride (high potency fluoride)
– Six month recall
– Fluoride supplements (depending on age of child and
absence of water fluoridation)
CARIES RISK GUIDELINES
(American Dental Association, 1996)
HIGH
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Two ore more carious lesions in last year
Past smooth surface caries
Elevated mutans streptococci count
Deep pits and fissures
No or little systemic and topical fluoride exposure
Plaque accumulation
Frequent fermentable carbohydrate intake
Irregular dental visits
Inadequate salivary flow
Inappropriate nursing habits (infants)
CARIES PREVENTION MODALITIES FOR
CHILDREN BY RISK CATEGORY
(American Dental Association, 1996)
HIGH
• Pit and Fissure Caries
– Sealants
• Smooth Surface Caries
– Education
– Dietary counseling
– Fluoride dentifrice
– Fluoride mouthrinse
– Professional topical fluoride (3-6 months)
– Three to six month recall
– Monitoring of mutans Streptococci
– Antimicrobial agents (Chlorohexidene)
– Fluoride supplements ( depending on age of child and
presence of water fluoridation
PREVENTION V
“DENTAL
(PIT AND FISSURE)
SEALANTS”
HISTORY
• The concept of sealing the fissures of teeth is over 100
years old. In 1895, Wilson, described in Dental Digest the
use of oxyphosphate cement to seal fissures.
• Contemporary pit and fissure sealants were introduced into
clinical dentistry in 1967 by Michael Buonocore of the
Eastman Dental Center, Rochester.
• Dr. Buonocore is credited with developing the field of
adhesive dentistry through his introduction of the concept
of acid etching of tooth enamel, and his documentation of
the ability of resin materials to ‘adhere’ to such etched
enamel surfaces.
• The effectiveness of pit and fissure sealants as a preventive
tool was recognized with provisional approval by the
American Dental Association Council on Dental Therapeutics
in 1971; full approval came in 1976.
• Since then the use of pit and fissure sealants, now generally
referred to as dental sealants, has increased steadily.
SEALANT USAGE
• Surveys show an increase in sealant use among dentists from
38% in 1974 to as high as 90-95% of dentists in recent
surveys.
• The U.S. Public Health Services goal for “Healthy People2000” called for at least 50% of children 8-14 to have
sealants placed.
• Although no studies of sealant prevalence have been
completed this year, it is thought that the prevalence of use
will fall far below this goal.
• The prevalence of sealant usage in eight year olds grew from
7% to 15% from 1986 to the early 90s; during the same time
period the percentage of fourteen year olds with sealants
grew from 8% to 35%. When all school aged children are
included, 18.5% had one or more sealed teeth in 1991.
CARIES PREVALENCE
• As we have discussed, there has been a significant decline in
caries prevalence among school aged children in the past 2030 years.
• Recall that the mean DMFS for school children in 1980 was
4.77, and had declined to 3.07 in 1986; a 36% reduction.
• 50% of school children were caries free in 1986, versus 37%
in 1980.
COMPARISON OF AGE-SPECIFIC
MEAN DMFS SCORES: 1980,1987
COMPARISON OF AGE-SPECIFIC
PERCENT OF CARIES FREE
CHILDREN: 1980,1987
RELATIVE DISTRIBUTION
OF CARIES
• Not only has there been a change in the number of tooth
surfaces affected by dental caries, but there has been a
change in the relative distribution, or pattern, of caries on
different tooth surfaces.
• There has been a greater percentage reduction for smooth
surface caries (mesial and distal surfaces) compared to pit
and fissure caries.
• According to the latest survey, 58 % of the caries observed
on school children’s teeth is observed on the occlusal
surfaces.
• Overall, 88% of the caries in school children occurs in
pits and fissures, and only 12% on the proximal surfaces.
• This differential is related to the more significant impact of
fluorides on smooth surfaces in reducing enamel solubility;
and serves to underscore the imperative of dental sealants
in a comprehensive program of prevention.
DISTRIBUTION OF DENTAL
CARIES BY TOOTH SURFACE
TYPE OF CHILDREN
TOOTH SURFACE ATTACK
RATES IN PERMANENT
TEETH BY SURFACE
PRINCIPLES UNDERLYING
SEALANT USE
• Prevention of dental caries is preferable to
treatment; sound, nondiseased teeth are to be
more highly valued than adequately restored
teeth.
• For equivalent outcomes, the least invasive
approach, using the simplest intervention for
managing dental caries is preferred.
• Minimizing the cost of preventing or controlling pit
and fissure caries is desirable.
• Strategies for sealant use may vary between
individual care and community-based programs.
SCIENTIFIC FACTS RELATED
TO SEALANT USE
• Sealants have been demonstrated to be a safe and
effective long-term method to prevent pit and
fissure caries.
• Pit and fissure caries attack begins in childhood
and continues through adolescence and into
adulthood.
• In addition to preventing carious lesions, sealants
can arrest caries progression.
• Effective sealant use requires meticulous
attention to detail in application technique,
particularly moisture control. Sealant retention
should be checked within one year of application.
RISK ASSESSMENT IN TREATMENT
PLANNING FOR SEALANTS
• Determination of the need for sealants begins with an
assessment of the individuals risk for dental caries, as well
as an assessment of the risk of the individual tooth.
• Factors contributing to individual risk include:
– caries history
– previous dental care
– use of preventive practices
– dietary habits
• Factors to evaluate when considering individual teeth
include:
– individual’s risk for developing caries
– pit and fissure morphology
– caries pattern
– status of the proximal surface of the tooth in question.
TREATMENT DECISION MAKING
• Studies suggest that the first and second permanent molars
are at the greatest risk for pit and fissure caries; premolars
are at significantly less risk.
• Primary teeth have an aprismatic layer of enamel and do not
etch in the same manner as permanent teeth, consequently
sealant retention is not as great on primary teeth.
Additionally, the grooves of primary teeth tend to be wellcoalesced in comparison to permanent teeth.
• In general, we do not seal primary teeth.
• The cost-benefit effectiveness is greatest in sealing first
and second permanent molars, and they should be given
preferential treatment to premolars in application of
sealants.
• Sealants are not necessarily indicated for permanent molars
with well-coalesced grooves and no history of dental caries.
• Indiscriminate sealing of teeth with low risk of caries
reduces the cost effectiveness of sealants.
EFFICACY OF SEALANTS
• Sealants are effective as long as they
remain intact. With complete
retention sealed surfaces are
virtually impervious to decay.
• Therefore, the effectiveness of
sealants in preventing decay is
measured by the retention of the
sealant.
VARIABLES AFFECTING
SEALANT RETENTION
• Position of the teeth in the mouth
– better sealant retention in mandibular versus maxillary
arch--???
• Skill of operator
– more skillful and experienced operators produce better
sealant retention
• Eruption status of the tooth
– the younger the child, the more difficult to maintain a
dry field due to the eruption status of the teeth;
partially erupted molars are difficult to isolate.
• Patient Cooperation
– children who present problems with cooperation make
gaining and maintaining a dry field more difficult.
SEALANT RETENTION
• A compilation and summary of over 75
studies of sealant retention
indicates:
– 94% of sealants were intact after one
year
– 83% of sealants were intact two years
after placement.
– 67% were intact five years after
placement.
– 57% were intact after ten years.
UPDATING TECHINQUE:
MATERIALS
• There is a wide variety of sealant materials from which to
choose.
• Sealants are often classified by their method of
polymerization, either autopolymerizing (chemically cured),
or visible light-cured sealants; they are also classified by
whether they are ‘filled’ resins, or ‘unfilled’ resins--though
increasingly the market is dominated by filled resins.
• Numerous studies have compared bond strengths and
retention rates between the two and found they offer
comparable results.
UPDATING TECHNIQUE:
CLEANING THE FISSURE
• Prior to acid etching the enamel, it is important to be sure
that the tooth surface and fissure areas are free of gross
plaque that might interfere with the etching process.
• Historically, it was recommended that this be done with a
prophylaxis cup or bristle brush and pumice.
• Recent studies have shown that cleaning the tooth with a
pumice prophylaxis does not significantly increase bond
strength.
• Current recommendation is to run an explorer through the
fissures and rinse forcefully with water; or, brush the
fissures thoroughly with a tooth brush to remove the gross
plaque.
• Complete debridement of plaque from the fissure is viewed
to be essentially impossible and not an imperative for
successful etching and sealant retention.
UPDATING TECHNIQUE:
ISOLATION
• Adequate isolation of the tooth is the most critical aspect
of the sealant application process.
• Salivary contamination of a tooth surface during or after
acid etching will have a deleterious effect on the ultimate
bond between the enamel and resin.
• Studies have shown that even a one second exposure of
etched enamel to saliva adversely affected bond strength
and sealant retention.
• Several studies have shown that rubber dam isolation and
cotton roll isolation provide comparable retention rates.
• However, it is obvious that rubber dam provides the best,
most controllable isolation.
• When sealants are treatment planned for a tooth in a
quadrant where restorative therapy will also be
accomplished, the sealant should be placed under rubber
dam isolation in the context of the restorative treatment.
UPDATING TECHNIQUE:
ETCHING
• The most commonly used etchant is 37% orthophosphoric
acid; it is available as both a liquid and a gel.
• Etchant should be applied to all of the fissures and extend
2mm up the the cuspal inclines.
• Soft tissue exposure to the etchant is to be avoided.
• Historically, etchant times were 30-60 seconds; however,
recent studies have concluded that 15-20 seconds is
comparable and adequate.
• Rinse time is not important as previously thought (20
seconds). What is critical is that the etchant be completely
rinsed away.
• On thorough drying the enamel should present a chalky,
frosted appearance; if it does not, it must be re-etched..
DEMINERALIZATION PATTERNS
(SEM X5,000)
Enamel prism
centers mainly
involved
DEMINERALIZATION PATTERNS
(SEM X 5,000)
Enamel prism
peripheries mainly
involved.
UPDATING TECHNIQUE:
APPLYING THE SEALANT
• All susceptible pits and fissures should be sealed; this
includes the buccal pit of mandibular molars, and the lingual
groove of maxillary molars.
• Some studies have shown that using a bonding agent as an
intermediate step, prior to placing the sealant increases
sealant retention. Other studies have not confirmed this.
Typically most recommended techniques, a bonding agent is
not required. However, it may be used if desired.
• Care should be taken not to place excess sealant, which may
affect the child’s occlusion; and increase the potential for
the sealant bond being fractured.
PENETRATION OF MICROSCOPIC
SEALANT TAGS
OCCLUSAL SEALANT AFTER
REMOVAL OF ENAMEL BY
DEMINERALIZATION
INNER SURFACE OF SEALANT
AFTER REMOVAL OF ENAMEL BY
DEMINERALIZATION
POLYMERIZED SEALANT
TAGS (SEM X 3,000)
UPDATING TECHNIQUE:
POLYMERIZATION
• In one study it was found that the longer sealants were
allowed to remain on the tooth surface before being
polymerized, the more sealant penetrated the
microporosities, creating longer resin tags, which are the
critical dimension for micromechanical retention.
• Sealants in which polymerization was not effected for 20
seconds after application, had nearly three times longer
resin tags than those of sealants polymerized after 5-10
seconds.
• When isolation can be adequately maintained, it appears to
be beneficial to wait for 20 seconds after sealant
application before applying the light activation.
UPDATING TECHNIQUE:
EVALUATING THE SEALANT
• All sealants should be visibly and tactually inspected for
complete coverage, and the absence of voids or air bubbles.
• Attempts should be made to dislodge the sealant with an
explorer.
• An evaluation of the occlusion should be conducted. Filled
resin sealants (which we utilize) in contrast to unfilled resin
sealants, are not easily abraded and can create occlusal
interferences. They should be adjusted with a rotary
instrument, if determined to be in hyperocclusion.
• The interproximals of the tooth should be evaluated as well
to ensure no sealant has flowed into the area inadvertently.