Journal of Indian Society of Pedodontics and Preventive Dentistry
Journal of Indian Society of Pedodontics and Preventive Dentistry
                                                   Official journal of the Indian Society of Pedodontics and Preventive Dentistry                           
Year : 2014  |  Volume : 32  |  Issue : 1  |  Page : 44--47

Relationship between severe-early childhood caries, salivary mutans streptococci, and lactobacilli in preschool children of low socioeconomic status in Bengaluru city

Priyadarshini Hesaraghatta Ramamurthy1, Hiremath Shivalinga Swamy2, Fernandes Bennete3, M Rohini4, T Nagarathnamma4,  
1 Department of Public Health Dentistry, Dr. Syamala Reddy Dental College, Bhopal, India
2 Department of Public Health Dentistry, Oxford Dental College, Bhopal, India
3 Department of Periodontics, Rishiraj Dental College, Bhopal, India
4 Department of Microbiology, Bangalore Medical College, Bengaluru, Karnataka, India

Correspondence Address:
Priyadarshini Hesaraghatta Ramamurthy
Department of Public Health Dentistry, Dr. Syamala Reddy Dental College, #1288, 4th Cross, Lalithadri Road, Kuvempunagar, Mysore - 570 023, Karnataka


Aim: To find out the relationship between severe-early childhood caries (s-ECC) and salivary counts of mutans streptococci (MS) and lactobacillus (LB) in preschool children of low socioeconomic status. Materials and Methods: A cross-sectional study was designed among 50 children aged 2-5 years selected from five Anganwadi centers in Bengaluru city. Clinical examination was carried out and caries status was recorded using the World Health Organization (WHO) criteria. Twenty-five children diagnosed with s-ECC based on American Association of Pediatric Dentistry (AAPD) criteria and 25 caries-free counterparts were selected. Whole non-stimulated saliva was collected from all children and cultured for MS and LB. Data were analyzed using SPSS version 14. Fisher«SQ»s exact test, Mann-Whitney test, and Spearman«SQ»s correlation were used to find out significant relationships. P values <0.05 were considered as statistically significant. Results: Twenty-one out of 25 children with s-ECC were positive for MS and 22 children were positive for LB. A significant difference in the mean number of MS colonies (12.2 vs. 4.16) and LB colonies (8.4 vs. 3.8) among children with s-ECC and caries-free counterparts (P < 0.01) was also found. A significant positive correlation was also found between caries experience and salivary MS and LB counts. Conclusion: s-ECC is positively correlated with salivary levels of both MS and LB in preschool children of low socioeconomic status. Suitable preventive strategies need to be planned when children are still young.

How to cite this article:
Ramamurthy PH, Swamy HS, Bennete F, Rohini M, Nagarathnamma T. Relationship between severe-early childhood caries, salivary mutans streptococci, and lactobacilli in preschool children of low socioeconomic status in Bengaluru city.J Indian Soc Pedod Prev Dent 2014;32:44-47

How to cite this URL:
Ramamurthy PH, Swamy HS, Bennete F, Rohini M, Nagarathnamma T. Relationship between severe-early childhood caries, salivary mutans streptococci, and lactobacilli in preschool children of low socioeconomic status in Bengaluru city. J Indian Soc Pedod Prev Dent [serial online] 2014 [cited 2022 Aug 14 ];32:44-47
Available from:

Full Text


Early childhood caries (ECC), the caries occurring in children below 71 months of age, [1] is recognized as an infectious disease affecting the primary dentition. [2] A significant percentage of preschool child population is affected by ECC today, with the disease concentrating disproportionately in deprived families. [3] s-ECC, the severe form of ECC, has serious consequences on primary dentition, affecting the overall health, well-being and the quality of life of the child. [4]

Even though dental caries is multifactorial, the crucial role of diet and microorganisms is well established in ECC. [5] The first step in its development is primary infection by mutans streptococci (MS). Lactobacilli (LB) are found to play a role in the progression of caries. [6] These acid-producing organisms inhabiting the mouth cause damage by dissolving tooth structures in the presence of fermentable carbohydrates. [7],[8]

However, determining the role of MS and LB in development of caries is a complex matter, as they are part of normal oral flora. Healthy subjects could have high counts and people with carious lesions may have no detectable counts of these bacteria in their mouths. [9],[10],[11]

Though both have cariogenic potential, studies have reported that mere presence of the organisms does not determine caries development, [12] indicating that there could be some kind of a relationship between the two.

While many studies have reported associations of high levels of MS and LB with dental caries in adults and older children, [13],[14] not many studies have been found reporting the same in young children with s-ECC.

Also, ECC is a serious public health concern, especially for socially disadvantaged groups in both developed and developing worlds, [15] due to lack of awareness and accessibility for dental care and high cost of treatment, stressing the importance of prevention.

Hence, this study was undertaken to find out the relationship between salivary MS, LB, and s-ECC, so that suitable preventive strategies could be planned when children are still young.

 Materials and Methods

A cross-sectional analytical study was undertaken among 50 children of 3-5 year age group, belonging to low socioeconomic status in Bengaluru city, Karnataka State, India. The study was approved by the Institutional Ethical Committee. The study was conducted in five anganwadi centers selected at random from the list of anganwadis in Bengaluru South obtained from the office of the Director, Women and Child Welfare Department, Bengaluru. Informed consent was obtained from the mothers of children. Clinical examination was carried out at the centers by a single calibrated examiner using mouth mirror and CPI probe under natural light. Caries was recorded using the World Health Organization (WHO) criteria. American Association of Pediatric Dentistry (AAPD) definition was adopted for classifying children with s-ECC. [1] Twenty-five children with s-ECC were selected. Twenty-five caries-free (CF) counterparts were also selected from the same centers. Children suffering from systemic diseases, children on long-term medication, and children who had taken antibiotics for less than 3 months were excluded from the study.

Sample collection

Whole non-stimulated saliva was collected. Children were refrained from swallowing for a minute and made to passively drool saliva in sterile disposable plastic containers. One milliliter of saliva was transferred to graduated tubes containing pre-reduced autoclaved Ringer's lactate solution using disposable sterile syringes. Tubes were transported on ice to laboratory and processed within 1 h.

Sample processing

All samples were vortex mixed for 30 s. A 100-fold dilution of sample was obtained using saline. 0.1 ml of this was transferred to Mitis Salivaris Bacitracin agar plates prepared using Gold's criteria. [16] 0.1 ml was transferred to Rogosa agar medium also. MSB agar plates were incubated in CO2 atmosphere for 48 h. Rogosa agar plates were kept in an anaerobic jar using gas pack for 72 h. Colonies were identified by morphology and gram staining. In addition, carbohydrate fermentation tests like mannitol and sorbitol fermentation tests were done to confirm the colonies. Colony-forming units were counted and multiplied by the dilution factor (10 4 ).

Statistical analysis

Data were analyzed using statistical software SPSS. [14] Differences in prevalence and mean bacterial counts of each bacterial species between S-ECC and CF children were evaluated by using the nonparametric Fisher's exact test and Mann-Whitney test. Nonparametric Spearman's correlation coefficient was used to find out correlations between mean bacterial levels and mean dmft/dmfs scores. P values <0.05 were considered as statistically significant.


The mean caries experience of children with s-ECC was 5.8 ± 2.8.

Out of 50 samples, 32 (64%) were positive for MS and 37 (74%) were positive for LB. [Table 1] shows the prevalence and mean levels of MS and LB among s-ECC and CF children.{Table 1}

Twenty-one children (84%) with s-ECC were positive for MS as compared to only 11 (44%) CF children. This difference was significant with P = 0.007.

Also, 22 (88%) children with s-ECC were positive for LB as compared to only 15 (60%) CF children (P = 0.041).

A significant difference was also found in the mean number of colonies of both MS and LB among s-ECC and CF children, according to Mann-Whitney test. While the mean number of MS colonies in s-ECC children was 12.2, the same for CF children was 4.16 (P = 0.003). The mean number of LB colonies in s-ECC children was 8.4, while in CF children, it was 3.8 (P = 0.015).

A significant positive correlation was also found between salivary MS level and caries experience (P = 0.016) and also between LB count and caries experience (P = 0.035). [Table 2] shows the correlation of salivary bacterial level with caries experience. While MS count was positively correlated with both dmft and dmfs, LB count showed correlation with dmft alone.{Table 2}

Another finding of the study was that 30 out of 50 (60%) children were positive for both MS and LB, of whom 20 (66.6%) had s-ECC as compared to only 10 (43.4%) CF children. This was significant with P = 0.004. [Table 3] shows the distribution of children positive for both MS and LB.

A significant positive correlation (not shown in table) was also found between MS count and LB count (cc = 0.28, P = 0.04), indicating that children with high caries experience had higher levels of both MS count and LB in their saliva.{Table 3}


Despite the decline in dental caries in western countries, ECC continues to be a significant public health problem in both industrialized and developing countries, especially concentrated in deprived families. [15] The results of the present study hold importance as it has been done on children from low socioeconomic background, who do not have awareness or access for dental care. The presence of severe untreated caries indicates a very high unmet treatment need among them.

Among the many risk factors for ECC, the role of sugars and microorganisms has been well established. Previous studies have shown that MS are strongly associated with dental caries by virtue of their metabolic, ecological, and epidemiological attributes. [17],[18],[19] Among the MS, Streptococcus mutans appears to be a predominant bacterial species in the microbiota of preschool children with s-ECC. [20],[21] Although the association between MS and s-ECC seems convincing, most children colonized by MS do not manifest the disease, [22] suggesting the possible role of other oral bacteria along with MS in causation of caries. Hence, the present study assessed both the salivary microbes.

Prevalence of ECC worldwide is highly variable owing to the differences in case definition and diagnostic criteria. In the present study, AAPD definition was used for s-ECC diagnosis and only frank cavitations were considered as caries, in order to keep the diagnosis non-ambiguous as the examination was carried out on an ordinary chair with limited light and instruments. Children of age 3-5 years were selected as they would have full complement of primary teeth.

The mean caries experience (dmft) of children with s-ECC was 5.8 ± 2.8 and the mean dmfs was 8.9 ± 7.4. All of the dmft was due to untreated caries without a single filling, indicating total lack of oral care and a high treatment need.

In the present study, salivary MS and LB were detected in more than 80% of children with s-ECC as compared to only about 50% of CF children. In a study conducted on Chinese preschool children, [22] MS and LB were isolated from 96.6% and 79.3% of children with ECC, respectively, which were significantly higher than those (63.7% and 27.5%, respectively) of CF children. There has been a high variation in the detection levels in different studies owing to differences in the type of salivary sample collected, microbiological methods used, and also variation in colonization time and pattern.

A large number of studies previously have established a positive correlation between MS and ECC. [23],[24] The results of the present study also confirmed that MS was associated with s-ECC in terms of both prevalence (more s-ECC children were positive) and the number of colonies (s-ECC children had more MS colonies). A positive correlation was also found between severity of s-ECC as measured by the dmft/dmfs index and high levels of MS counts, indicating that as the number of colonies increased, the number of teeth and surfaces affected by caries also increased.

Studies conducted previously on the relationship between LB and ECC in children report different opinions. Some studies showed a positive correlation, [11],[13],[25] while some could not find any correlation between LB and ECC. [26],[22] Yet, some studies have reported that LB could have a beneficial effect by reducing the S. mutans count. [27] The present study found a positive correlation between salivary LB and dmft, but, however, no significant relationship was found between LB count and the number of decayed surfaces. In the present study, LB count could be high as only cavitated lesions were diagnosed as caries. The caries lesions might serve as retentive sites for the additional bacterial load.

Another important finding in the study was a significant positive correlation between the two salivary microbes, indicating a combination of the two could be responsible for s-ECC. These findings not only support the notion that the presence of MS alone may not be the sole indicator for increased risk for caries [23] but also suggest that a combined effect of MS and LB may play an important role in determining children's caries experience.

In conclusion, this study demonstrated that s-ECC is associated not only with increased levels of salivary MS but also with elevated levels of LB in this study population of preschool children of low socioeconomic status. A large number of untreated cavitated lesions in these children may have been responsible for the increased bacterial counts. Also, an important consideration is the influence of other factors like diet, nature and frequency of sucrose consumption, oral hygiene practices, exposure to fluorides, etc., which could have a significant impact on the salivary microbial counts and have not been considered in the present study. Hence, a detailed study of these factors is required in the same direction.


1American Association of Pediatric Dentistry (AAPD). Early childhood caries: Unique challenges and treatment options. Pediatr Dent 2000;22:21.
2Poureslami HR, Van Amerongen WE. Early Childhood Caries (ECC): An Infectious transmissible oral disease. Indian J Pediatr 2009;76:191-4.
3Vadiakas G. Case definition, aetiology and risk assessment of Early Childhood Caries (ECC): A revisited review. Eur Arch Pediatr Dent 2008;9:114-25.
4Petersen PE, Estupinan-Day S, Ndiaye C. WHO's action for continuous improvement in oral health. Bull World Health Organ 2005;83:642.
5Palmer CA, Kent R JR, Loo CY, Hughes CV, Stutius E, Pradhan N, et al. Diet and caries associated bacteria in severe early childhood caries. J Dent Res 2010;89:1224-9.
6Van Houte J. Role of microorganisms in caries etiology. J Dent Res 1994;73:672-81.
7Schafer TE, Adair SM. Prevention of dental disease. The role of the pediatrician. Pediatr Clin North Am 2000;47:1021-42.
8Caufield PW, Griffen AL. Dental caries. An infectious and transmissible disease. Pediatr Clin North Am 2000;47:1001-19.
9Berkowitz RJ. Mutans Streptococci: Acquisition and Transmission. Pediatr Dent 2006;28:106-9.
10Thenisch NL, Bachmann LM, Imfeld T, Leisebach Minder T, Steurer J. Are mutans streptococci detected in preschool children a reliable predictive factor for dental caries risk? A systematic review. Caries Res 2006;40:366-74.
11Martínez-Pabón MC, Ramírez-Puerta BS, Escobar-Paucar GM, Franco-Cortés AM. Physiochemical salivary properties, lactobacillus, mutans streptococci counts and early childhood caries in preschool children of Colombia. Acta odontol Latinoam 2010;23:249-56.
12Ge Y, Caufield PW, Fisch GS, Li Y. Streptococcus mutans and Streptococcus sanguinis Colonization Correlated with Caries Experience in Children. Caries Res 2008;42:444-8.
13Aguilera Galaviz LA, Premoli G, Gonzalez A, Rodriguez RA. Caries risk in children: Determined by levels of mutans streptococci and Lactobaccilus. J Clin Pediatr Dent 2005;29:329-3.
14Hegde PP, Ashok Kumar BR, Ankola VA. Dental caries experience and salivary levels of Streptococcus mutans and Lactobacilli in 13-15 years old children of Belgaum city, Karnataka. J Indian Soc Pedod Prev Dent 2005;23:23-6.
15Çolak H, Dülgergil CT, Dalli M, Hamidi MM. Early childhood caries update: A review of causes, diagnoses, and treatments.J Nat Sci Biol Med 2013;4:29-38.
16Gold OG, Jordan HV, Van Houte J. A selective Medium for Streptococcus Mutans. Arch Oral Biol 1973;18:1357-64.
17Becker MR, Paster BJ, Leys EJ, Moeschberger ML, Kenyon SG, Galvin JL, et al. Molecular analysis of bacterial species associated with childhood caries. J Clin Microbiol 2002;40:1001-9.
18Tang JM, Altman DS, Robertson DC, O'Sullivan DM, Douglass JM, Tinanoff N. Dental caries prevalence and treatment levels in Arizona preschool children. Public Health Rep 1997;112:319-29.
19Milnes AR, Bowden GH. The microflora associated with developing lesions of nursing caries. Caries Res 1985;19:289-97.
20Tinanoff N. Introduction to the Early Childhood Caries Conference: Initial description and current understanding. Community Dent Oral Epidemiol 1998;26:5-7.
21Ercan E, Dulgergil CT, Yildirim I, Dalli M. Prevention of maternal bacterial transmission on children's dental-caries-development: 4-year results of a pilot study in a rural-child population. Arch Oral Biol 2007;52:748-52.
22Zhou Q, Bai J, Qin M. Relationship between cariogenic microbe, salivary buffer capacity and early childhood caries. Chinese J stomatology 2007;42:581-4.
23Loesche WJ. Role of streptococcus mutans in human dental decay. Microbiol Rev 1986;50:353-80.
24Berkowitz R. Etiology of nursing caries: A microbiologic perspective. J Public Health Dent 1996;56:51-4.
25AI Shukairy H, Alamoudi N, Farsi N, AI Mushayt A, Masoud I. A comparative study of streptococcus mutans and lactobacilli in mothers and children with severe early childhood caries (secc) versus a caries free group of children and their corresponding mothers. J Clin Pediatr Dent 2006;31:80-5.
26Toi CS, Mogodiri R, Cleaton-Jones PE. mouth of children with and without dental caries. Microbial Ecology in Health and Disease 200;12:35-41.
27Badet C, Thebaud NB. Ecology of Lactobacilli in the Oral Cavity: A Review of Literature. Open Microbiol J 2008;2:38-48.