Dental Cariology Lecture Notes PDF

Dental Cariology Dr.Doaa Alhelais Introduction "The day is shortly coming when we will engage in practicing preventive rather than reparative dentistry, when we will understand the etiology and pathology of dental caries that will be able to compete its destruction eff...

Dental Cariology Dr.Doaa Alhelais Introduction "The day is shortly coming when we will engage in practicing preventive rather than reparative dentistry, when we will understand the etiology and pathology of dental caries that will be able to compete its destruction effect by systemic medications" GV BLACK What is caries? multifactorial, transmissible, infectious oral disease of the teeth that result in localized dissolution & destruction of the calcified tissue.  Because all criteria of infectious disease can be applied: There is source of infection "bacteria". Host resistance plays a role. Can be transmitted by media (saliva). It is an infectious disease..Why?? If not treated well it will reoccur. Depend on virulence of the microorganism (threshold dose). There is incubation period for the microorganism. Can cause tissue damage. Etiology of Dental Caries: Cariogenic bacteria in the biofilm metabolize refined carbohydrates for energy and produce organic acid byproducts. These organic acids, if present in the biofilm ecosystem for extended periods, can lower the pH in the biofilm to below a critical level (5.5 for enamel, 6.2 for dentin). The low pH drives calcium and phosphate from the tooth to the biofilm in an attempt to reach equilibrium, hence resulting in a net loss of minerals by the tooth Demineralization. pH in the biofilm returns to neutral and the concentration of soluble calcium and phosphate is supersaturated relative to that in the tooth, mineral can then be added back to partially demineralized enamel, in a process called Remineralization. Cariogenic bacteria PH PH Carbohydra te and sugar  Understanding the balance between demineralization and remineralization is key to caries management.  The balance between demineralization and remineralization has been illustrated in terms of pathologic factors (factors for demineralization) and protective factors (factors for reminarlization) It is essential to understand that caries lesions, or cavitations in teeth, are signs of an underlying condition, an imbalance between protective and pathologic factors favoring the latter. What are these factors???  What makes this disease complicated that there are multiple factors that play a role in causing of the disease.  Although symptomatic treatment is important, failure to identify and treat the underlying causative factors allows the disease to continue  Ecologic Factors of Dental Caries 1-The Role of the Biofilm Dental plaque is a term historically used to describe the soft, tenacious film accumulating on the surface of teeth. dental Dental plaque plaque used is a term historically hastobeen describemore the soft,recently referred tenacious film toonastheasurface accumulating plaque biofilm, of teeth. or simply biofilm. Biofilm is composed mostly of bacteria, their by-products, extracellular matrix, and water  The accumulation of biofilm on teeth is a highly organized and ordered sequence of events. Many of the organisms found in the mouth are not found elsewhere in nature. Dental plaque is a term historically used to describe the soft, tenacious film accumulating on the surface of teeth. Survival of microorganisms in the oral environment depends on their ability to adhere to oral surfaces such as the mucosa and tooth structure.  Free-floating organisms are cleared rapidly from the mouth by salivary flow and frequent swallowing. Only a few specialized organisms, primarily streptococci, are able Free-floating organisms are cleared rapidly from the mouth by salivary flow and frequent swallowing. Only a few specialized to primarily organisms, adhere to oralaresurfaces streptococci, such able to adhere to oralas thesuch surfaces mucosa andandtooth as the mucosa structure. tooth structure.  The pits and fissures on the crown may harbor a relatively simple population of streptococci, the root surface in the gingival sulcus may harbor a complex community dominated by filamentous and spiral bacteria. Professional tooth cleaning is intended to control biofilm (plaque) and prevent disease  Ecologic Basis of Dental Caries 2-Tooth Habitats for Cariogenic Biofilm Tooth habitats favorable for harboring pathogenic biofilm include (1)pits and fissures. (2)The smooth enamel surfaces immediately gingival to the proximal contacts. (3)The Professional gingival tooth cleaningthird of the is intended facialbiofilm to control and lingual surfaces (plaque) and prevent of the clinical crown. disease (4)Root surfaces, particularly near the cervical line; and subgingival areas These sites correspond to the locations where caries lesions are most frequently found.  Ecologic Basis of Dental Caries Tooth Habitats for Cariogenic Biofilm Professional tooth cleaning is intended to control biofilm (plaque) and prevent disease  Ecologic Basis of Dental Caries 3-Saliva: Nature’s Anticaries Agent Saliva plays a key role as a natural anticaries agent : Salivary flow rate, salivary Buffering capacity. Salivary protective mechanisms that maintain the normal oral flora Professional tooth cleaning is intended to control biofilm (plaque) and prevent disease and tooth surface integrity include : 1. Bacterial clearance 2. Direct antibacterial activity 3. Buffers. 4. Remineralization  1. Bacterial clearance : The flushing effect of this salivary flow is, by itself, adequate to remove virtually all microorganisms not adherent to an oral surface 2. Direct antibacterial activity : Salivary Professional toothglands cleaning isproduce intended to an impressive control array biofilm (plaque) of antimicrobial and prevent disease Products. Lysozyme, lactoperoxidase, lactoferrin, and agglutinins possess antibacterial activity. These protective proteins are present continuously at relatively uniform levels, have a broad spectrum of activity.  3. Buffers: The buffering capacity of saliva is determined primarily by the concentration of bicarbonate ion. The benefit of the buffering is to reduce the potential for acid formation. Professional tooth cleaning is intended to control biofilm (plaque) and prevent disease 4. Remineralization : Saliva and biofilm fluid are supersaturated with calcium and phosphate ions. This supersaturated state of the saliva provides a constant opportunity for remineralizing enamel  Ecologic Basis of Dental Caries Individuals with decreased salivary production (owing to illness, medication, or irradiation) may have significantly higher caries susceptibility Professional tooth cleaning is intended to control biofilm (plaque) and prevent disease  Ecologic Basis of Dental Caries 4-Oral Hygiene and Its Role in the Caries Process Oral hygiene including proper tooth brushing and flossing, is another ecologic determinant of caries onset and activity. The cleaning process does not destroy most of the oral bacteria Professional tooth cleaning is intended to control biofilm (plaque) and prevent disease but merely removes them from the surfaces of teeth. Careful mechanical cleaning of teeth disrupts the biofilm and leaves a clean enamel surface.  Ecologic Basis of Dental Caries 4- Diet and caries High-frequency exposure of fermentable carbohydrates such as sucrose may be the most important factor in producing cariogenic biofilm. Professional tooth cleaning is intended to control biofilm (plaque) and prevent disease when ingestion of fermentable carbohydrates is severely restricted or absent, biofilm growth typically does not lead to caries.  Ecologic Basis of Dental Caries 4- Diet and caries Professional tooth cleaning is intended to control biofilm (plaque) and prevent disease  Ecologic Basis of Dental Caries Professional tooth cleaning is intended to control biofilm (plaque) and prevent disease Ecologic Basis of Dental Caries  Ecologic Basis of Dental Caries every time you eat something, the pH drops below the critical point of 5.5. It takes 30-40 minutes for your saliva to get you back to the safe zone. The longer you snack for, the longer you are at risk and the longer it takes for your mouth to recover.  REFRENCE Art and science of operative dentistry 6th edition ch:2 Thank you