Dental Caries PDF

‫بسم هللا الرمحن الرحمي‬ Dental Caries Prepared By DR. Naema Al-Kakalli  Definition of dental caries It is a bacterial disease of calcified tissues of the teeth characterized by demineralization of the inorganic and destruction of the organic substance of the tooth Aetiology ; U...

‫بسم هللا الرمحن الرحمي‬ Dental Caries Prepared By DR. Naema Al-Kakalli  Definition of dental caries It is a bacterial disease of calcified tissues of the teeth characterized by demineralization of the inorganic and destruction of the organic substance of the tooth Aetiology ; Unknown But there are predisposing factors Theories Of Dental Caries Acidogenic theory Protolytic theory Protolysis chelating theory  I-Acidogenic theory Acid ( lactic acid ) is produced from bacteria as a result of fermentation of CHO ( sucrose ) which causes demineralization of calcified tissues and destruction of organic tissues Factors of acidogenic theory ; it depends on … ❑Bacteria…………. ( Streptococci mutans , sanguis , Actinomyces and Lactobacillus ) ❑salivaris ) ❑CHO ………………….( Sucrose and fructose ) ❑Host ❑Time Acidogenic Theory  Role Of Bacteria Types of bacteria ; ( Streptococci mutans , S. sanguis , S. mitis , S. salivaris , Actinomyces and Lactobacillus ) ▪ S. Mutans has a role in initiation of dental caries but , lactobacillus has an important role in the further progression of dental caries ▪ Actinomyces has a role in root caries  Dental plaque It is a bacterial matrix formed of collection bacterial colonies and adhesion to the tooth surface by extracellular bacterial polysaccharides in the form of ( Glucans ( adhesive matrix ) which derived from affecting of bacteria on proteins of saliva )  Role Of CHO Types of diets ……CHO…..Sucrose , Fructose ,maltose ,galactose and fructose ✓Sucrose …fermentable by Bacteria. to lactic acid ✓Sucrose …… decreasing of PH of saliva ……...acidity media ….causes demineralization of hard tissues ( cariogenic factors ) CHO………..Bacteria by Glucosyl transferase ……changes into……….. extracellular glucans ❖There is a direct relationship between increasing of CHO and caries index ……….. Especifically , the consumption of CHO is between meals…..  Role Of Host ❑Factors related to tooth structures ; o Quality of mineralization or tooth compositions o Position of the tooth o Morphology of the tooth ❑Factors related to the oral cavity ; o Saliva ; its flow rate , viscosity, buffering capacity , its mineralized contents ,presence of antimicrobial agents such as Ig A , thiocyanate ion ,lactoferrin and lysosomes o PH o Oral hygiene o Diet ; increase intake proteins …….decrease caries index  II-Protolytic theory ; It is characterized by the bacteria secretes protolytic enzymes to destruct organic substances and removing inorganic substances….. III-Protolysis chelating theory ; It is characterized by the bacteria secretes protolysis enzymes to destruct organic substances and chelating agents to removing inorganic substances at same time.  Classification Clinically dental caries is divided to ; ❑According to the sites ; ▪ Pit and fissure caries ▪ Smooth surfaces caries ▪ Cemental caries ❑According to rate of attack ; ▪ Acute or Rampant caries ▪ Chronic or Slowly Progressive caries ▪ Arrested caries ❑According to time of attack ; ▪ Primary caries Recurrent or Secondary caries  Clinical Diagnosis ▪Chief complain of the patient ▪Probing ▪Cavitation ▪Colour ; Chalky -whitish or brownish in colour ▪X-Ray ; radiolucent area  Enamel Caries Histopathologically TDBS in early lesion By using the transmitted electron ( polarized light microscopes) ; according to diameter of porosity which are presence within a decalcified enamel……. Clinically. Shape ; ❖Pit and fissure caries In the form of a cone – shaped lesion from surface to DEJ and change its shape to inverted cone form DEJ to deeply within the dentine , this shape can be seen in Pit and fissure caries  ❖Smooth surface caries In the form of an inverted cone – shaped lesion from surface to DEJ and change its shape to a cone form DEJ to deeply within the dentine , this shape can be seen in a smooth surface caries  Enamel caries has four zones Translucent zone …….large and more porous than normal (N =0.1 % by volume ) Dark zone……..larger and more than TZ with areas of remineralization ( 2-4 % by volume ) Body zone…….the pores volume between ( 5-25 % by volume ) Surface zone………thickness of the pores in about 40 micron , because there is a highly mineralization from saliva ( increasing fluoride content )  Dentine Caries Histopathologically SDBDR The dentine is a vital tissue characterized by has ability to response to bacterial attack by defence reaction pulpdentinal complex by ( tertiary dentine , sealing of dead tract and dentinal sclerosis ) Dental caries has five zones Sclerosis zone…………oblliteration of dentinal tubules by calcification Demineralization………….infected and soft dentine with sterile dentine  Bacterial invasive zone …………..colonies of bacterial invasion with poinor bacteria within DTs , infected DTs appear in the form of Liquefaction foci ( parallel to long axis of DTs ) Destruction zone……. infected LDTs appear in the form of transverse clefts ( laterally extension) Reactionary zone ……………….at surface of pulp chamber deep to dentine caries ( localized where irritation of odontoblasts is present and characterized by hypermineralization of DTs  Cementum Caries It is a dental caries involved root surface Aetiology ; as a result of chronic periodontal diseases and Actinomyces , Streptococci mutans and Lactobacilli infection Clinical features ; Age ; old age Sex ; males Site ; roots of P-M teeth Shape ; Saucer –shaped lesion Colour ; brownish in colour Histopathologically ; Demineralization of the cementum and extension deeply to the dentine and surface layer is characterized by hypermineralization and remineralization ( from saliva or plaque ) Thank You