Dental caries is an epidemic, microbial, contagious disease of teeth that leads to localized dissolution and damage of calcified structure of the teeth.
The oral cavity is known to be a harbor for a variety of microorganisms. Around 700 bacterial species have been detected intraoral, according to a study in the journal of bacteriology. A harmonious balance is maintained in the microbial ecosystem by these microorganisms contributing to normal development and in regulation of acidity of the mouth. However, any disruption or change in this balance due to any influence can result in an unfavorable and pathological shift toward various oral diseases.
Under the normal Ph of the mouth mainly streptococci are the key microorganisms responsible for dynamic stability of the tooth surface whereas in the presence of generous host carbohydrates intake and the absence of scrupulous oral hygiene, Streptococcus mutans (a facultative, anaerobic gram positive cocci) is able to strongly adhere to teeth via synthesis of a glucan matrix, and to rapidly dominate dental plaque by using glycolytic end-products to acidify the microenvironment, kill competitors and lower the Ph level at which enamel of the teeth starts to de-mineralize leading to tooth decay known as dental caries.
World Oral Health Day celebrated
Dental caries is an epidemic, microbial, contagious disease of teeth that leads to localized dissolution and damage of calcified structure of the teeth. There have been a number of theories concerning the etiology of dental caries, among which the acidogenic theory has been the most generally accepted, also referred to as chemo-parasitic theory by WD Miller.
W D Miller recognized four important factors in his study of the carious process, roles of microorganisms, roles of carbohydrates, substrate over tooth and role of dental biofilm. According to Miller, the carious process occurs in two phases. In the initial stage there is decalcification of enamel and dentine, and the second phase involves dissolution of softened residue of enamel and dentine.
When highly fermentable carbohydrate such as sucrose, fructose and glucose are frequently consumed, they are broken down by Streptococcus mutans that leads to lactic acid production, these products of bacterial metabolism accumulate in the dental biofilm over the tooth surface and causes drop in pH and start de-mineralization of the surface. Dental biofilm is a mass of microorganisms that grow on surfaces of the tooth, which are sticky and colorless deposits at first. In healthy state dental biofilm and adjacent tooth tissue maintain a delicate balance however change in microbial balance and frequent consumption of fermentable carbohydrates without disruption in formation of biofilm will transform the biofilm to pathogenic plaque leading to caries formation.
Despite the complexity of disease initiation and progression, Streptococcus mutans is nevertheless the organism most frequently associated with the development of caries, and a reduction of its population in the oral cavity remains the primary goal in research aimed at reducing or eliminating the disease.
A prerequisite for controlling biofilm and preventing caries is good oral hygiene habits keeping the oral microorganisms at levels compatible with the oral environment. Parents and public dental care for children and adolescents are the key persons for teaching and securing optimal oral hygiene until children and adolescents are able to take care of tooth brushing with dentifrice containing fluoride. This effort is also crucial in the dental care system for adults and for elderly in hospitals and nursing homes, and when necessary supplemented with interdental brushes, or dental floss. If de-mineralization of teeth is advanced, professional treatment including application of fluoride and ultimately filling therapy is recommended.
Regardless of widespread and improvised education regarding oral hygiene, dental caries remains a prevalent disease associated with a tremendous economic burden around the globe affecting 2.3 billion people.
