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PREVETION OF DENTAL CARIES. dr shabeel pn. INTRODUCTION.
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PREVETION OF DENTAL CARIES dr shabeel pn
INTRODUCTION Dental caries is defined as a progressive irreversible microbial disease affecting the hard parts of tooth exposed to the oral environment, resulting in demineralization of the inorganic constituents and dissolution of the organic constituent, thereby leading to a cavity formation. • The word caries derived from Latin meaning ‘rot’ or decay • Similar to the Greek word ‘ker’ meaning death • The relationship between diet and dental caries Bacterial enzymes + fermentable carbohydrates = acid,Acid + enamel = dental caries
CURRENT TRENDS IN CARIES INCIDENCE • In developed countries, caries prevalence declined in last decade, causes are multifactorial. Eg: communal water fluoridation. • In developing countries increase in caries prevalence, cause is increased use of refined carbohydrates.
CARIES SUSCEPTIBILITY JAW QUADRANTS • Bilateral distribution between the right and left quadrant of both maxillary and mandibular arches. • Maxillary teeth more susceptible than mandibular arch relate to gravity and saliva, with its buffering action, would tends to drain from upper teeth and collect around lower teeth.
CARIES SUSCEPTIBILITY OF INDIVIDUAL TEETH • Upper and lower first molar 95% • Upper and lower second molar 75% • Upper second bicuspid 45% • Upper first bicuspid 35% • Lower second bicuspid 35% • Upper central and lateral incisor 30% • Upper cuspids and lower first bicuspid 10% • Lower central and lateral incisor 3% • Lower cuspids 3% • Teeth farthest back in the mouth are more frequently carious. • Caries susceptibility of individual tooth surface occlusal > mesial > buccal > lingual
ECONOMIC IMPLICATION OF DENTAL CARIES Factors changing the economic implication of treatment of dental caries :- • Economic status of population • Increasing educational status • Growing number of dental graduates • Insurance programs • Commercial pressure • Governmental influences
CLASSIFICATION OF DENTAL CARIES A) Black’s classification CLASS I – cavities on the occlusal surface of premolars and molars, on the occlusal two-third of the facial and lingual surface of molars, on lingual surface of maxillary incisors. CLASS II – cavities on the proximal surface of posterior teeth CLASS III - cavities on the proximal surface of anterior teeth that do not include the incisal angle CLASS IV – cavities on the proximal surface of anterior teeth that include the incisal angle CLASS V – cavities on the gingival third of the facial or lingual surface of all teeth CLASS VI - cavities on the incisal edge of anterior teeth or occlusal cusp height of posterior teeth
B[1] According to location on individual teeth • Pit and fissure caries • Smooth surface caries B[2] According to the rapidity of the process • Acute dental caries • Chronic dental caries B[3] • Primary caries (virgin) • Secondary caries (recurrent)
PIT AND FISSURE CARIES • Pits and fissures with high steep walls & narrow base retention of food, debris, micro organisms fermentation acid production • Caries appear brown/ black, feel soft • Enamel bordering opaque bluish white • Large carious lesion with a tiny point of opening
SMOOTH SURFACE CARIES • Preceded by formation of microbial/ dental plaque • Begins just below contact point and appear in early stages as faint white opacity of enamel (chalky spot) slightly roughened surrounding enamel bluish white as caries penetrate enamel • Cervical carious lesion crescent shaped cavity (extend from areas opposite to the gingival crest occlusally to convexity of tooth surface)
ACUTE DENTAL CARIES • Rapid clinical course & early pulp involvement • Process rapid little time for deposition of sec. dentin. Dentin stained a light yellow • Rampant caries, affecting deciduous dentition nursing bottle caries • Commonly 4 maxillary incisors followed by first molar and then cuspids • Absence of caries in mandibular incisors distinguished from ordinary rampant caries
CHRONIC DENTAL CARIES • Progress slowly and leads to involve pulp much later • Sufficient time for both sclerosis deposition of sec. dentin • Carious dentin stained deep brown. • cavity shallow with min. softening of dentin • Pain and undermining of enamel not a common feature RECURRENT CARIES • Occurs in immediate vicinity of restoration • Poor adaptation of filling material
ARRESTED CARIES • Static or stationary caries • Exclusively in caries of occlusal surface • Large open cavity and lack of food retention • Superficially retained and decalcified dentin gradually burnished until it takes a brown stain, polished appearance and is hard EBURNATION OF DENTIN • Caries on proximal surface of teeth adjacent approx. tooth extracted
THEORIES OF CARIES FORMATION • Legend of the worm theory • Endogenous theories • Humoral theory • Vital theory • Exogenous theory • Chemical (acid) theory • Parasitic (septic) theory • Miller’s chemicoparasitic theory – Acidogenic theory • Proteolysis theory • Proteolysis chelation theory • Sucrose – chelation theory • Other theories • Auto immune theory • Sulfatase theory
ETIOLOGIC FACTORS IN DENTAL CARIES • Dental caries is a multifactorial disease in which there is an interplay of 3 principle factors. I. The host ( teeth, saliva etc.) II. Micro flora III. Substrate (diet) • In addition the fourth factor, time must be considered.
I. HOST FACTORS Tooth • Composition • Morphologic characteristics • Position
Composition of tooth Enamel:- • Inorganic : 96% • Organic + water : 4% Dentin:- - Organic matter +water :35% - Inorganic :65% Cementum:- • Inorganic : 45-50% • Organic +water : 50- 55%
Morphological characteristics of the tooth • Feature predisposed to the development of dental caries is presence of deep narrow occlusal fissure/ buccal and lingual pits Tooth position • Which are malaligned, out of position, rotated or otherwise not normally situated, may be difficult to clean and tend to favor the accumulation of food and debris which subsequently lead to dental caries
Saliva • Composition • PH • Quantity • Viscosity • Antibacterial factors
Composition of saliva Inorganic:- Positive ions:- Ca, Mg, K, Negative ions:- CO2, Cl, F, PO4, thiocynate Organic:- Carbohydrates : glucose Lipids : cholesterol, lecithin Nitrogen : non- protein ammonia, nitrites & amino acids protein globulin, mucin, total protein Miscellaneous : peroxides Enzymes : carbohydrases, proteases, oxidases
PH of saliva • Determined by bicarbonate concentration • PH increases with flow rate, normal PH 7.8 • Sialin is an argenine peptide described PH rise factor, present in saliva Quantity of saliva • Normal quantity 700-800 ml per day • In case of salivary gland aplasia and xerostomia in which salivary flow may entirely lacking, resulting in rampant dental caries Viscosity of saliva • Thick, mucinous saliva increases the dental caries
Antibacterial properties of saliva Lactoperoxidase • They participate in killing of microorganisms by catalyzing the H2O2 mediated oxidation of a variety of substances in the microbes • Utilizing thiocynate ions in saliva peroxidation generate highly reactive chemical compound that bond and inactivate general intracellular microbial enzyme system, as well as microbial surface compound. Lysozyme • Small, highly positive enzyme that catalyze the degradation of negatively charged peptidoglycan matrix of microbial cell wall
Lactoferin • Fe binding basic protein found in saliva with mol. wt. near 80,000. • Tends to bind & link the amount of the free Fe which is essential for microbial growth IgA • Immunoglobulin in saliva • Inhibit adherence and prevent colonization of microbial on tooth and mucosal surfaces Other salivary components with protective function Proline rich protein • Mucus and glycoprotein • Because of their high proline content, there are rigid collagen like molecules designed to form a pseudo membranous layer in the hard and soft oral surfaces as well as on the oral flora. Aromatic rich protein • Statherin • It causes remineralization
Other host factors Age • Dental caries decreases as age increases • Root caries are common in elders • Gingival recession cemental exposure (improper brushing) Socioeconomic status • High low chance • Low more chance
II. MICROFLORA • Strep. mutans early carious lesions of enamel • Lactobacilli dentinal caries • Actinomyces root caries
Role of microorganisms in dental caries • Prerequisite for dental caries initiation • A single type of microbe is capable of inducing dental caries • Ability to produce acid prerequisite for caries induction • Streptococcus strains are capable of inducing caries • Organisms vary greatly in their ability to induce caries
Role of dental plaque • soft, non mineralized, bacterial deposit which forms on a teeth that are not adequately cleaned • Complex metabolically interconned highly organized bacteria/ ecosystem • Important component of dental plaque is acquired pellicle just prior or concomitantly with bacterial colonization and may facilitate plaque formation • Microbial in dental plaque streptococci actinomycetes veillonella • Strep. mutans chief etiological agent of dental caries
III. DIET • Increase in carbohydrate increase carious activity • Risk of caries is greater if the sugar is consumed in a form that will be retained on the surface of the teeth • Risk of sugar increasing caries activity if it is consumed between meals • Increasing caries activity varies widely between individuals • Upon withdrawal of the sugar rich foods the increased caries activity rapidly disappears • Carious lesion may continue to appear desperate to avoidance of refined sugar and maximum restriction on natural sugars dietary carbohydrates • High concentration sugar in solution and its prolonged retention on the tooth surface leads to increased caries activity • Clearance time of the sugar correlates closely with caries activity
THE CARIES PROCESS • Caries of enamel smooth surface caries pit and fissure caries • Caries of dentin • Caries of cementum
SMOOTH SURFACE CARIES • Earliest manifestation is the appearance of an area of decalcification, beneath dental plaque with a smooth chalky white area • Loss of interprismatic substance with increase in prominence and roughening of ends of enamel rods • Accentuation of incremental striae of retzius • As this process advances and involves deeper layer of enamel it forms a cone shaped lesion with apex towards DEJ and base towards surface of teeth
PIT AND FISSURE CARIES • Because pit and fissure provides more depth increased food stagnation with bacterial decomposition • Here caries follow direction of enamel rods and forms a cone shaped lesion with apex at outer surface and base towards DEJ Different zones present in lesion are Zone 1: translucent zone Advancing front of enamel lesion, not always present Zone 2: dark zone Referred as positive zone formed as a result of demineralization Zone 3: body of lesion Area of greatest mineralization Zone 4: surface zone Appears relatively unaffected
CARIES OF DENTIN • Initial penetration of dentin by caries may result in dentinal sclerosis • This is a reaction of vital dentinal tubules and a vital pulp, in which results in calcification of dentinal tubules, that tend to seal them off against further penetration by microorganisms • The different zones which are present in carious dentin are (beginning pulpally at advancing edge of lesion) Zone 1 : zone of fatty degeneration of Tome’s fibres Zone 2 : zone of degeneration Zone 3 : zone of decalcification Zone 4 : zone of bacterial invasion of decalcified but intact dentin Zone 5 : zone of decomposed dentin
ROOT CARIES • Defined as soft progressive lesion that is found anywhere on root surface that has lost connective tissue attachment and exposed to oral environment • Microorganisms involved in root caries are filamentous • Microorganisms invade cementum, along sharpey’s fibres
INDICES USED TO ASSESSMENT OF DENTAL CARIES • DMFT index • DMFS index • DEF index • Stone’s index • Caries severity index Diagnosis of caries • Identification of subsurface demineralization (inspection/ palpation, radiographs) • Bacterial testing (caries activity testing) • Assessment of environment conditions like salivary PH, flow and buffering
METHODS OF CARIES CONTROL • There are various levels for prevention of dental caries these include • Primary prevention • Secondary prevention • Tertiary prevention