**1. Introduction**

270 Contemporary Approach to Dental Caries

[88] Yilmaz Y., Beldüz N., Eyüboglu O.:A two-year-evaluation of fluor different fissure

[89] Zimmerman-Downs JM., Shuman D., Stull SC., Ratzlaff RE.: Bisphenol A blood and

saliva levels prior to and after dental sealant placement in adults. J Dent.

sealants. Eur.Arch Paediatr Dent.2010, 11 (2) 88-92.

Hyg.2010;84(3):145-150.

Dental caries and periodontal disease are major public health problems that bother all countries in the world. Dental carie is an infectious, communicable disease that acid-forming bacteria of dental plaque can destroy tooth structure 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. So, the infection results in loss of tooth minerals from the outer surface of the tooth and can progress through the dentin to the pulp, finally compromising the tooth vitality. Industrialized nations have controlled the problem with fluoride enriched water and personal hygiene products since early in the 1960s, but cariogenicity remains a crisis that economically burdens the health care system. Dental disease remains a "silent epidemic" in the world that threatens children and adults. The oral streptococci especially mutans Streptococci are related with the development of caries in humans and animals (Caglar et al., 2001; Natcher, 2001; Kargul, 2003). For the past 150 years, the predominant mode of caries management has been the surgical approach, predating our current understanding and reliable with the original concept that dental caries was a gangrenous process resulting in extraction of carious teeth. Later, just the demineralized portions of the tooth were removed and replaced with an inert restorative material. This mechanical solution for a biological problem prevailed.

Today, dental practitioners still teach the removal of diseased tooth structure which suggests we should expect a "cure". The insight however, is that it has repeatedly been shown not to remove the causative infection. There is a paradigm shift in the management of dental caries. Research in cariology is sky-rocketing, bringing out hidden facts of this ageold disease, but education and clinical practice are adopting them at a snail's pace. In clinical practice dental caries is still being treated symptomatically, just like the common cold. Clinicians have adopted a comfort level from many years of practicing 'restorative' dentistry, but unlike the common cold that does not have a cure, dental caries has abundant options to be cured and eradicated (Anderson and Shi, 2006; Carounanidy, 2010).

Throughout the past few decades, changes have been observed not only in the incidence of dental caries, but also in the distribution and pattern of the disease in the population. These changes have main hints for diagnosis and management of early lesions, predicting caries risk, and conducting effective disease prevention and management programs for

Probiotics and the Reduction of Dental Caries Risk 273

maximized. Stage IV (apoptosis or death) signals detachment or sloughing from the biofilm

Fig. 2. Four stages of dental plaque biofilm growth: Stage I attachment (lag [not inert, but metabolically reduced]), Stage II growth (log [exponential growth]), Stage III maturity

For therapeutic purposes, it is necessary to attack the formed biofilm. For prophylactic purposes, it seems reasonable to target processes involved in the actual biofilm formation of single- or mixed-bacterial communities that have the potential to cause or support disease, without disturbing the balance of the normal flora. It is known that the mature oral biofilm is the result of a well regulated series of processes, which begins by adhesion of planktonic

The shift in the treatment paradigm incorporates the ecological plaque hypothesis, which states that prevention of disease should not only focus on the putative pathogens inhibition, but also on interference with environmental factors that drive selection and enrichment for these bacteria as reported by Marsh(2005). One of the key characteristics of biofilm that could be targets for dental plaque management includes its behavior as an adhesive mass. The environmental key factors in concerned with biofilm formation are the fermentable dietary carbohydrates and Streptococci, as pioneer strains, depend on them as an energy source (Tahmourespour et al., 2010). The cariogenicity of sugar-containing foods can be modified by many factors including the amount and type of carbohydrates, protective components (proteins, fats, calcium, phosphate, fluoride) and physical and chemical properties (liquid vs. solid retentiveness, solubility, pH, buffering capacity). The fact that sugars are readily metabolized by oral bacteria, leading to the production of organic acids and extra cellular polysaccharides such as glucan and fructan was shown repeatedly in clinical studies (Zero, 2004; Touger et al., 2003). Numerous studies have established the role

cells to the surfaces and could represent potential targets for biofilm control.

(stationary) and Stage IV dispersal (death) ( Thomas et al 2006).

**3. Dental plaque biofilm management** 

(Donlan & Costerton, 2002; Thomas et al., 2006).

populations. In order to make continued progress in eliminating this, new strategies will be required (Natcher, 2001).The broad management of dental caries should involve the management of disease as well as the lesion. There is now an intense focus on preventive strategies. Essentially, all preventive treatment strategies either alter or modify the causative factors in dental caries etiology, such as diet, host, salivary, and microbial factors.

Numerous anti-plaque agents available in the market have been tested for their ability to interfere dental biofilm formation or metabolism. However, due to several undesirable side effects associated with these agents, going along with the increasing global problem with antimicrobial drug resistance, the search for alternate agents is necessary (Tahmourespour, 2011). Targeted agents are so expected to be highly specific, to pose an insignificant resistance development problem, and to have minimal effects on vital human cell functions. A suggested approach to overcome the limitations of the traditional disease management strategies is using inexpensive, effective, stable, novel and natural products as anti biofouling agent. Whole bacteria replacement therapy or using natural products of some bacteria such as the secondary metabolites of them for decreasing of oral cavity pathogens must be investigate.
