Preventive Dentistry I

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Preventive Dentistry I II

• Dental caries

Dr. Caroline Mohamed
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Objectives

• Define
• Dental caries
• The dental caries process
• The role of diet in dental caries
• Classification of dental caries
• Epidemiology
• Incidence and prevalence and how can be measured
• Caries risk

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1. Dental caries definition

• Dental caries is a multifactorial microbial
  disease of the calcified tissues of the teeth,
  characterized by demineralization of the
  inorganic portion and destruction of the organic
  substance of the tooth, which often leads to
  cavitations.

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• Two groups of bacteria are responsible for
  initiating caries Streptococcus mutans and
  Lactobacillus. If left untreated, the disease can
  lead to pain, tooth loss, infection, and, in
  severe cases, death.
• Today, caries remains one of the most common
  diseases throughout the world.
• Cariology is the study of dental caries.

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• The presentation of caries is highly variable
  however, the risk factors and stages of
  development are similar. Initially, it may appear
  as a small chalky area that may eventually
  develop into a large cavitation.
• Sometimes caries may be directly visible, however
  other methods of detection such as radiographs
  are used for less visible areas of teeth and to
  judge the extent of destruction.

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• Tooth decay is caused by specific types of
  acid-producing bacteria that cause damage in the
  presence of fermentable carbohydrates such as
  sucrose, fructose, and glucose.
• The mineral content of teeth is sensitive to
  increases in acidity from the production of
  lactic acid. Specifically, a tooth (which is
  primarily mineral in content) is in a constant
  state of back-and-forth demineralization and
  remineralization between the tooth and
  surrounding saliva.
• When the pH at the surface of the tooth drops
  below 5.5, demineralization proceeds faster than
  remineralization (meaning that there is a net
  loss of mineral structure on the tooth's
  surface). This results in the ensuing decay.

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Educational level
Socio-Economical Situation
FLORA Fluoride in plaque Lactobacilli Oral
Hygiene Streptococci Virulence factors Transmissib
ility
HOST Age Fluoride Genetics Morphology Nutrition
SUBSTRATE Carbohydrates Frequency of eating Oral
clearance Physical nature of food Detergency of
food
SALIVA pH Flow rate Composition Buffering
capacity Bicarbonate levels
SALIVA
Knowledge
Behavior
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The role of diet in dental caries
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Substrate

• Readily fermentable
• Sucrose- arch criminal
• Cariogenicity determined by
• Frequency of ingestion
• Physical form
• Chemical composition-detergency
• Texture of food
• Presence of other constituents

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Cariogenicity determined by

• Frequency of ingestion

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Frequency of ingestion
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Tooth enamel dissolves at 5.5 ph
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Chemical composition-detergency

• Cows milk (cheese) contains calcium, phosphorus,
  and casein
• Wholegrain foods require more chewing
• Peanuts, hard cheeses, and chewing gum
• Black tea extract ( fluoride)

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CARIES PROCESS
CA R I E S
Pulpal lesion
RESTORATION
Dentin lesion
Enamel lesion
CAVITY
White spot

• NO CAVITY

De-Remineralization
DIAGNOSIS
Colonization
TIME
Adhesion
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• Depending on the extent of tooth destruction,
  various treatments can be used to restore teeth
  to proper form, function, and aesthetics, but
  there is no known method to regenerate large
  amounts of tooth structure, though stem cell
  related research suggests one possibility.
• Instead, dental health organizations advocate
  preventive and prophylactic measures, such as
  regular oral hygiene and dietary modifications,
  to avoid dental caries.

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EpidemiologyDefinition of Epidemiology

• The word epidemiology comes from the Greek
  words
• epi , meaning on or upon
• demos , meaning people, and
• logos , meaning the study of
• "the study of what is upon the people",

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Incidence and prevalence and how can be measured

• Prevalence
• Number or proportion of persons in a population
  affected by a condition at a given point of time
• Can be expressed as, count, proportion or
  percentage.
• Incidence
• Number of new cases of condition over a given
  point of time.
• Change in prevalence or severity. The period of
  time depend on time needed to disease to be
  observed
• expressed as a rate (case per the population
  per time)
• Determine the progress of condition

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Different Age Groups

• Key risk groups from ages
• Age-Three peaks
• 4-8yrs
• 11-18yrs
• 55-65yrs
• 1 to 2 years ( baby bottle caries)
• 5 to 7 years ( primary caries)
• 11 to14 years
• Key risk age group in young adults
• and adults ( secondary caries/ root caries)
• Sex- both sexes
• early eruption in females

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• Adults continue to experience primary dental
  caries, but they also experience a significant
  amount of secondary caries around existing
  restorations.
• Children today, in developed countries, have
  comparatively few, if any restorations and
  experience mostly primary caries of the
  noncavitated type.
• Between 40 and 76 of dental carie in adults are
  arrested, a condition uncommoly observed in
  children.

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Variation within dentition

• Early plaque formation occurs faster.
• In lower jaw, compared to upper jaw.
• In molars areas.
• On buccal tooth surfaces, compared to oral sites.
• In interdental regions compared to strict buccal
  or oral surface.

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Tooth composition

• Mineralization-
• Hypomineralization/ Dentinogenese imperfecta
• Trace elements
• Fluoride/ dental fluorose

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• Dentinogenese imperfecta Dental Fluorose

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Individual Teeth

• First primary molars and first permanent molars
  are high risk.

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Different tooth surfaces

• Are high risk
• Interproximal surfaces of primary molars.
• Occlusal surfaces of first permanent molars.

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Tooth morphology

• Pits fissures
• Irregularities in arch form
• Crowding
• Overlapping

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• Tooth morphology

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Behavior

• Age

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• Regularity of snaks, more than 3 times a day,
  snacking between meals, this increases the acid
  challenge to the teeth for a high level
• Nocturnal bottle usage- additive
• On pacifier during sleep
• Breast feeding
• (Kawaba et al., 1997)

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• Drinking sweet beverage
• Brushing by mother
• (Kawaba et al., 1997)

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• Dental Caries classification
• 1.based on anatomical site
• 2.based on progression
• 3.based on virginity of lesion
• 4.based on extend of caries
• 5.based on tissue involvement
• 6.based on chronology
• 7. based on whether caries is completely removed
  or not.
• 8.based on surfaces to be restored
• 9. WHO system
• 9.Blacks classification
• 10.Caries risk Assessement

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Classification
1) Based on anatomic site
Root caries
Crown caries
Pit Fissure Caries
Smooth surface Caries
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Pits and fissures are anatomic landmarks on a
tooth where the enamel folds inward. Fissures are
formed during the development of grooves but the
enamel in the area is not fully fused. As a
result, a deep linear depression forms in the
enamel's surface structure, which forms a
location for dental caries to develop and
flourish. Fissures are mostly located on the
occlusal surfaces of posterior teeth and palatal
surfaces of maxillary anterior teeth.
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Pits are small, pinpoint depressions that are
most commonly found at the ends or cross-sections
of grooves. In particular, buccal pits are found
on the facial surfaces of molars. For all types
of pits and fissures, the deep infolding of
enamel makes oral hygiene along the surfaces
difficult, allowing dental caries to develop more
commonly in these areas.  
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The occlusal surfaces of teeth represent 12.5 of
all tooth surfaces but are the location of over
50 of all dental caries. Among children, pit and
fissure caries represent from 80 to 90 of all
dental caries. Pit and fissure caries can
sometimes be difficult to detect. As the decay
progresses, caries in enamel nearest the surface
of the tooth spreads gradually deeper. Once the
caries reaches the dentin at the dentino-enamel
junction (DEJ), the decay quickly spreads
laterally.
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Within the dentin, the decay follows a triangle
pattern that points to the tooth's pulp. This
pattern of decay is typically described as two
triangles (one triangle in enamel, and another in
dentin) with their bases conjoined to each other
at the DEJ. This base-to-base pattern is typical
of pit and fissure caries, unlike smooth-surface
caries (where base and apex of the two triangles
join).
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• Clinical Manifestation
• Entry site may appear much smaller than actual
  lesion, making clinical diagnosis difficult.
• In cross section, the gross appearance of pit and
  fissure lesion is inverted V with a narrow
  entrance and a progressively wider area of
  involvement closer to the DEJ.
• a) Initially, caries of pit fissures appears
  brown or
• black in color with fine explorer, it
  will feel soft a
• catch is felt ( dont do it ).
• The enamel which borders the pit fissures
  appears
• opaque bluish white.

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• Shape, morphological variation and depth of pit
  and fissures contributes to their high
  susceptibility to caries.
• The appearance of s.mutans in pits and fissures
  is usually followed by caries 6 to 24 months
  later.
• Sealing of pits and fissures just after tooth
  eruption may be the most important event in their
  resistance to caries.

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• Smooth surface caries
• Smooth surface caries occurs on the gingival
  third of
• the buccal, lingual proximal surfaces.
• On proximal surface, caries begins below the
  contact area
• in early stage this appear as a faint white
  opacity of
• enamel without loss of continuity of surface.
• As caries progresses, it appears bluish white
  in later
• stage.
• Caries in cervical area are in the form of
  crescent
• shaped cavities. It appear as a slightly
  roughened,
• chalky area which gradually becomes deeper

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Types of smooth surface caries

• Proximal caries, also called interproximal
  caries, form on the smooth surfaces between
  adjacent teeth.
• Root caries form on the root surfaces of teeth.
• The third type of smooth-surface caries occur on
  any other smooth tooth surface. Less favorable
  site for plaque attachment, usually attaches on
  the smooth surface that are near the gingiva or
  are under proximal contact.

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• Proximal caries are the most difficult type to
  detect. Frequently, this type of caries cannot be
  detected visually or manually with a dental
  explorer.
• Proximal caries form cervically (toward the roots
  of a tooth) just under the contact between two
  teeth. As a result, radiographs (bitewings) are
  needed for early discovery of proximal caries.

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• In very young patients the gingival papilla
  completely fills the interproximal space under a
  proximal contact and is termed as col. Also
  crevicular spaces in them are less favorable
  habitats for s.mutans.
• Consequently proximal caries is less lightly to
  develop where this favorable soft tissue
  architecture exists.

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• Proximal surfaces Caries
• The proximal surfaces are particularly
  susceptible to caries due to extra shelter
  provided to resident plaque owing to the proximal
  contact area immediately occlusal to plaque.
• Lesion have a broad area of origin and a
  conical, or pointed extension towards DEJ.
• V shape with apex directed towards DEJ.
• After caries penetrate the DEJ softening of
  dentin spread rapidly and pulpally

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Root surface caries

• The proximal root surface, particularly near the
  cervical line, often is unaffected by the action
  of hygiene procedures, such as flossing, because
  it may have concave anatomic surface contours
  (fluting) and occasional roughness at the
  termination of the enamel.
• These conditions, when coupled with exposure to
  the oral environment (as a result of gingival
  recession), favor the formation of mature,
  caries-producing plaque and proximal root-surface
  caries.

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• Root-surface caries is more common in older
  patients. Caries originating on the root is
  alarming because
• 1. It has a comparatively rapid progression
• 2. it is often asymptomatic
• 3. it is closer to the pulp
• 4. it is more difficult to restore

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• Characteristics of root caries
• Root caries lesions have less well-defined
  margins, tend to be U-shaped in cross sections,
  and progress more rapidly because of the lack of
  protection from and enamel covering.

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• When the gingiva is healthy, root caries is
  unlikely to develop because the root surfaces are
  not as accessible to bacterial plaque.
• The root surface is more vulnerable to the
  demineralization process than enamel because
  cementum begins to demineralize at 6.7 pH, which
  is higher than enamel's critical pH.
• Regardless, it is easier to arrest the
  progression of root caries than enamel caries
  because roots have a greater reuptake of fluoride
  than enamel.

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• Root caries are most likely to be found on facial
  surfaces, then interproximal surfaces, then
  lingual surfaces.
• Mandibular molars are the most common location to
  find root caries, followed by mandibular
  premolars, maxillary anteriors, maxillary
  posteriors, and mandibular anteriors.

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2) BASED ON THE PROGRESSION OF THE LESION
Progressive caries
Arrested caries
Rapidly progressive - Acute
Slowly progressive- Chronic
Nursing caries
Radiation caries
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Acute caries

• Acute caries is a rapid process involving a large
  number of teeth.
• These lesions are lighter colored than the other
  types, being light brown or grey, and their
  caseous consistency makes the excavation
  difficult.
• Pulp exposures and sensitive teeth are often
  observed in patients with acute caries.
• It has been suggested that saliva does not easily
  penetrate the small opening to the carious
  lesion, so there are little opportunity for
  buffering or neutralizaton

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Nursing caries

• Nursing caries can also be called as
• 1. Nursing bottle caries
• 2. Nursing bottle syndrome
• 3. Milk bottle syndrome
• 4. Baby bottle tooth decay
• 5. Early childhood caries
• The new name given for early childhood caries is
  maternally derived streptococcus mutans disease
  (MDSMD)

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NURSING CARIES This is the type of acute
carious lesion, which occurs among those
children who take milk or fruit juices by
nursing bottle, for a considerably longer
duration of time, preferably during sleep. As the
child takes larger amount of easily fermentable
sugars along with the milk, the sugar facilitates
the cariogenic bacteria to produce caries at a
rapid pace by fermenting those sugars. Nursing
bottle caries commonly occurs in the upper
anterior teeth (as these are constantly coming in
contact with the sweetened milk) while the lower
teeth are not usually affected as they remain
under the cover of the tongue.
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Radiation caries

• Radiotherapy is frequently associated with
  xerostomia due to decreased salivary secretion
• This and other cause of decreased salivation may
  lead to a rampant form of caries, indicating the
  significance of saliva in preventing caries.

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Radiation caries
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• Three types of defects due to irradiation
• Lesion usually encircling the neck of teeth
  amputation of crowns may occur
• Begins as brown to black discolouration of tooth
  .occlusal surface and incisal edges wear away
• Spot depression which spreads from any surface

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Chronic caries

• These lesions are usually of long-standing
  involvement, affect a fewer number of teeth, and
  are smaller than acute caries.
• Pain is not a common feature because of
  protection afforded to the pulp by secondary
  dentin
• The decalcified dentin is dark brown and
  leathery.
• Pulp prognosis is hopeful in that the deepest of
  lesions usually requires only prophylactic
  capping and protective bases.
• The lesions range in depth and include those that
  have just penetrated the enamel.

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Arrested caries

• Caries which becomes stationary or static and
  does not show any tendency for further
  progression
• Both deciduous and permanent affected.
• With the shift in the oral conditions, even
  advanced lesions may become arrested .
• Arrested caries involving dentin shows a marked
  brown pigmentation and induration of the lesion
  (the so called eburnation of dentin).
• Sclerosis of dentinal tubules and secondary
  dentin formation commonly occur.

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• Arrested caries
• Exclusively seen in caries of occlusal surface
  with large open cavity in which there is lack of
  food retention.
• Also on the proximal surfaces of tooth in cases
  in which the adjacent approximating tooth has
  been extracted

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3) BASED ON THE VIRGINITY OF THE
LESION Primary Caries
Secondary or
Recurrent
caries

Recurrent caries is that occurring
immediately next to a restoration. It may be the
result of poor adaptation of a restoration, which
allows for a marginal leakage, or it may be due
to inadequate extension of the restoration. In
addition, caries may remain if there has not been
complete excavation of the original lesion, which
later may appear as a residual or recurrent
caries.
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Primary caries

• A primary caries is one in which the lesion
  constitutes the initial attack on the tooth
  surface.
• The designation of primary is based on the
  initial location of the lesion on the surface
  rather than the extent of damage.

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Secondary caries (Recurrent)

• This type of caries is observed around the edges
  and under restorations.
• The common locations of secondary caries are the
  rough or overhanging margin and fracture place in
  all locations of the mouth.
• It may be result of poor adaptation of a
  restoration, which allows for a marginal
  leakage, or it may be due to inadequate extension
  of the restoration.
• In addition caries may remain if there has not
  been complete excavation of the original lesion,
  which later may appear as a residual or recurrent
  caries.

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4.Based on the extend of the lesion- severity
INCIPIENT CARIES
CAVITATION
OCCULT CARIES
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Incipient caries

• The early caries lesion best seen on the smooth
  surfaces of the teeth, is visible as a White
  Spot
• Histologically, the lesion has an apparently
  intact surface layer overlying subsurface
  demineralization.
• Significantly many such lesions can under go
  remineralization thus the lesion is not an
  indication for restorative treatment
• Remineralised with fluoride application
• D/d developmental defects of enamel

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Occult caries

• Occult or hidden caries is used to describe such
  lesion, which is not clinically diagnosed but
  detected only on radiographs.
• It is believed that bitewing OPG radiographs
  along with other noninvasive adjuncts like
  fibrooptic transillumination (FOTI), LASER
  luminescence, electrical resistance method(ERM)
  are used for diagnosing these occlusal lesions.
• Prevalence-0.8-50 in age range of 14 -20 yrs

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Cavitation
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Cavitation

• Once it reaches the dentinoenamel junction, the
  caries process has the potential to spread to the
  pulp along the dentinal tubules and also spread
  in lateral direction.
• Thus some amount of sensitivity may be associated
  with this type of lesion.
• This may be generally accompanied by cavitation

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5. Based on tissue involvement

• Initial caries- demineralization
• Superficial caries- enamel
• Moderate caries- dentin caries
• Deep caries dentin close to the pulp
• Deep complicated caries pulp involvement

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• Dental caries can be divided into 4 or 5 stages
• 1. Initial caries Demineralization without
  structural defect.
• This stage can be reversed by fluoridation and
  enhanced mouth hygiene
• 2. Superficial caries (Caries
  superficialis)Enamel caries, wedge-shaped
  structural defect.
• Caries has affected the enamel layer, but has not
  yet penetrated the dentin. Includes larger
  lesions with adequate tooth structure to support
  the restoration

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• 3. Moderate caries (Caries media) Dentin caries.
  Extensive structural defect. Caries has
  penetrated up to the dentin and spreads
  two-dimensionally beneath the enamel defect where
  the dentin offers little resistance.
• 4. Deep caries (Caries profunda) Deep structural
  defect. Caries has penetrated up to the dentin
  layers of the tooth close to the pulp.
• 5. Deep complicated caries (Caries profunda
  complicata) Caries has led to the opening of the
  pulp cavity (pulpa aperta or open pulp).

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6. Based on chronology
EARLY CHILDHOOD CARIES
ADULT CARIES
ADOLESCENT CARIES
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Early childhood caries

• Early childhood caries would include, two
  variants Nursing caries and rampant caries.
• The difference primarily exist in involvement of
  the teeth (mandibular incisors) in the carious
  process in rampant caries as opposed to nursing
  caries.

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Teenage caries (adolescent caries)

• This type of caries is a variant of rampant
  caries where the teeth generally considered
  immune to decay are involved.
• The caries is also described to be of a rapidly
  burrowing type, with a small enamel opening.
• The presence of a large pulp chamber adds to the
  woes, causing early pulp involvement.

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Adult caries

• With the recession of the gingiva and sometimes
  decreased salivary function due to atrophy, at
  the age of 55-60 years, the third peak of caries
  is observed.
• Root caries and cervical caries are more commonly
  found in this group.
• Sometime they are also associated with a partial
  denture clasp.

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7.Based on whether caries is completly removed or
not during treatment

• RESIDUAL CARIES
• Residual caries is that which is not removed
  during a restorative procedure, either by
  accident, neglect or intention.
• Sometimes a small amount of acutely carious
  dentin close to the pulp is covered with a
  specific capping material to stimulate dentin
  deposition, isolating caries from pulp.
• The carious dentin can be removed at a later time.

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8.Based on surfaces to be restored

• Most widespread clinical utilization
• O for occlusal surfaces
• M for mesial surfaces
• D for distal surfaces
• F for facial surfaces
• B for buccal surfaces
• L for lingual surface
• Various combinations are also possible, such as
  MOD for mesio-occluso-distal surfaces.

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9.World health organization (WHO) system

• In this classification the shape and depth of the
  caries lesion scored on a four point scale
• D1. clinically detectable enamel lesions with
  intact (non
• cavitated) surfaces
• D2. Clinically detectable cavities limited to
  enamel
• D3. Clinically detectable cavities in dentin
• D4. Lesions extending into the pulp

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10. Assessement tools

• Stepwise progression toward diagnosis
  treatment planning depends on thorough assessment
  of the following
• Patient History
• Clinical examination
• Nutritional analysis
• Salivary analysis
• Radiographic assessment

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Conventional techniques of measuring and
recording decay

• Visual exam
• Mirror and explorer
• Dental radiographs
• Dyes
• Transillumination
• Dmfs/dmft

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VISUAL-TACTILE METHODS

• Visual methods
• Detection of white spot, discoloration / frank
  cavitations.
• Unable to detect subsurface caries.
• Magnification loupes- Head worn prism loupes (X
  4.5) or surgical microscopes (X 16) may be used.
• Use of temporary elective tooth separation.

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• Tactile methods
• Explorers,Dental floss.
• Use of explorer is not advocated because
• Sharp tips physically damage small lesions with
  intact surfaces.
• Probing can cause fracture cavitation of
  incipient lesion. It may spread the organism in
  the mouth.
• Mechanical binding may be due to non-carious
  reasons Shape of fissure
• Sharpness of explorer
• Force of application
• Path of explorer placement
• Explores should be used to clean debris
• from teeth.

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X-rays

• non destructive
• can detect subsurface caries
• - limited safety
• - unable to detect incipient
• demineralization
• - low resolution

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Bitewings/ Periapical

• Radiographic imaging of pit and fissures is of
  minimal diagnostic value because of the large
  ammount of sorrounding enamel enamel.
• It is detrimental if used for non-invasive
  remineralization methods.

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Direct fiberoptic transillumination

• Enhanced visual technique that uses the principle
  of illuminating teeth to detect the presence of
  caries.
• . (Pretty, Maupomé, 2004) 

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Dental Caries Index DMF-T Decayed, Missed,
Filled Teeth

• D Decayed / not treated yet
• M Missed / extracted because decayed
• F Filled / restored after decay
• T Permanent teeth
• dmf-t Primary teeth
• S Surface
• DMF-S / dmf-s
• ( Mesial/ Distal/ Vestibular
• / Occlusal)

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DMF-T CHART
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10. G. V. BLACK CLASSIFICATION
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CLASS 1 pit and fissure cavities that occur in
the occlusal surfaces of bicuspids and molars,
the occlusal two thirds of the buccal and lingual
surfaces of the molars, and the lingual surfaces
of incisors. Cavities beginning in structural
defects that occasionally occur on the occlusal
or incisal two third of all teeth.
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CLASS 2 cavities in the proximal surfaces of
bicuspids and molars
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CLASS 3 Cavities in the proximal surfaces of
incisors and cuspids, not involving the incisal
angle
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CLASS 4 Cavities in the proximal surfaces of
incisors and cuspids involving the incisal angle
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CLASS 5 Cavities in the gingival third, not pit
and fissures cavities, of the labial, buccal and
lingual surfaces of all teeth
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CLASS 6 Cavities on both mesial and distal
proximal surfaces of bicuspid and molars that
when restored will share a common isthmus or
cavities on the incisal edges of anterior or cusp
tip of posterior teeth.
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HIGH RISK LOW RISK
Social History Social History
Socially deprived High caries in siblings Low knowledge of caries Middle class Low caries in sibling High dental aspirations
Medical History Medical History
Medically compromised Xerostomia Long-term cariogenic medicine No such problem
Dietary habits Dietary habits
Sugar intake frequent Infrequent
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HIGH RISK LOW RISK
Use of fluoride Use of fluoride
Non-fluoridated area No fluoride supplements Fluoridated area Fluoride supplements used
Plaque control Plaque control
Poor oral hygiene maintenance Good oral hygiene maintenance
Saliva Saliva
Low flow rate buffering capacity ? S.mutans lactobacillus counts Normal flow rate buffering capacity ? S.mutans lactobacillus counts
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HIGH RISK LOW RISK
Clinical evidence Clinical evidence
New lesions Premature extractions Anterior caries restorations Multiple/repeated restorations No fissure sealants Multi-band orthodontics No new lesions No extraction for caries Sound anterior teeth No/few restorations Fissure sealed No appliances
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Thank you
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Activity

• What is a fluoride bomb or fluoride syndrome?