the multi - factorial etiology of the disease necessitates the evaluation and combination of multiple factors.1 although past caries experience has been recognized as the best single caries predictor , other factors must be assessed , especially in children who have not yet developed clinical signs of the disease.2 in very young children , several single caries risk factors have been studied . the highest accuracy ( 92% ) was reported for the presence of upper labial plaque3 followed by mutans streptococci ( ms ) levels ( 75%).4 the combination of salivary ms and the presence of white - spot lesions has shown a prediction accuracy of 80%.5 high predictive values in preschool children have been demonstrated in statistical models when several factors , such as ms levels , sugar consumption , salivary parameters , parental background , and maternal education , have been included.6,7 the drawback of such models is , however , the difficulty of their application in routine clinical settings . several organizations have incorporated the evidence from the literature into daily dental practice by constructing caries risk assessment models for different age groups . however , these models do not normally provide a grading scale and do not disclose the weight and importance of each caries risk factor . the cariogram is a simple and handy tool for caries risk assessment.8 this computerized program considers the interaction of ten different caries risk factors , assesses the risk for new carious lesion development within the next 12 months and graphically presents the caries risk profile of an individual . in prospective trials , the cariogram has been satisfactorily validated in teenagers9 and adults,10 although it was found to be less useful in younger schoolchildren11 and preschool children.12,13 in cross - sectional studies , the cariogram has been used to explore the caries risk profiles of adults,10,14 young adults,15,16 teenagers9,17,18 and schoolchildren.19 in only one previous cross - sectional study , the cariogram was used for 2-year - old children.20 as that study group was limited in size , it was of interest to further investigate the cariogram concept in a broader preschool setting . the aim of this study was therefore to assess the caries risk profiles in 2- to 6-year - old greek children with the aid of cariogram software and to evaluate the contribution of various risk factors among preschool children of different ages . the study group consisted of 2- to 6-year - old children attending public day care centers and kindergartens in the athens metropolitan area . the mean age of the children was 54 months , ranging between 24 and 72 months . the study included children i ) who were born in greece , ii ) who were cooperative for oral clinical examination , iii ) who had not taken antibiotics for 15 days prior to the examination , and iv ) whose parents had returned their written informed consent and a completed questionnaire . among the 936 children who were initially eligible , 814 fulfilled the inclusion criteria and were included in the study . no dental care was routinely offered to these children , and there was no water fluoridation in this area . this was a cross - sectional study , and the protocol was approved by the ethics committee of the school of dentistry , university of athens . a letter explaining the procedures , a consent form , and a questionnaire were sent to the parents . the questionnaire consisted of closed - type questions regarding the family , demographic and socioeconomic factors , general health , oral hygiene and dietary behaviour of the child . parents with an immigrant background and a language barrier were assisted by the child s teacher when filling out the forms . the oral examination was performed in the classroom by three calibrated examiners , under a light source , using a dental mirror and a probe . the level of oral hygiene was estimated with the visible plaque index ( vpi ) , and the percentage of tooth surfaces with plaque was calculated for each child . caries was recorded as  cavity in the dentin and/or enamel  according to who criteria21 after visual inspection of the smooth surfaces and visual and tactile inspection of the pits and fissures . missing teeth were scored only if it was verified that the loss was due to caries . the presence of white spot lesions ( wsl ) , chalky white spots with unbroken surfaces , was recorded separately . no radiographs were taken . to assess the degree of inter - examiner agreement , 20 children were examined by each of the 3 examiners on the same day . the degree of intra - examiner agreement was established through an examination of 20 children by each examiner , and the procedure was repeated after 4 weeks . the mean inter - examiner and intra - examiner kappa values were k=0.89 and k=0.86 , respectively . mutans streptococci levels were estimated by sampling the upper anterior teeth with a cotton swab according to the protocol proposed by twetman and grindefjord.22 the swab was rolled on a dentocult sm strip ( orion diagnostica , helsinki , finland ) and incubated at 37c for 48 hours . the readings were performed by a single examiner , and 30 strips were reassessed after 15 days storage at 4c . buffer capacity was categorized as high / medium or low using a dentobuff strip ( orion diagnostica ) . unstimulated saliva was collected from the floor of the mouth with a pipette and placed on the strip ; the color changes were registered after 5 minutes . the intra - examiner reliability was k=0.87 for the buffer test and k=0.82 for the ms test . the scored data from the clinical examinations and the questionnaire were entered in the cariogram software . the chance to avoid caries over the next 12 months salivary secretion rate  was omitted as a variable , because it was considered difficult to adequately determine the stimulated saliva flow in this age group . moreover , the scores described in the cariogram manual for adults were modified to fit the present age group , as shown in table 1 . for example ,  previous caries experience  was scored in only two groups : those having caries and those who were caries free . any existing systemic disease was taken into consideration only if it directly or indirectly influenced the caries process ( asthma , diabetes , heart problems ) . the content of unfavorable carbohydrates in the diet ( muffins , cookies , chocolate , honey , marmalade , juice , candies , beverages and sweetened yogurt ) was extracted from the questionnaire . the diet frequency was modified by merging two categories into one and taking the frequency of 45 meals / day as normal for the age group . medium and high buffer capacity scores were incorporated into one group . in the  clinical judgment  section of the cariogram was finally grouped in three levels : low chance 0%20% ( high caries risk ) , moderate chance 21%60% ( moderate caries risk ) , and high chance 61%100% ( low caries risk ) . all data were processed by stata software ( stata 9 , stata corp lp , texas , usa ) . in addition to descriptive statistics , multivariate regression analysis was used to associate the cariogram variables with caries risk . the study group consisted of 2- to 6-year - old children attending public day care centers and kindergartens in the athens metropolitan area . the mean age of the children was 54 months , ranging between 24 and 72 months . the study included children i ) who were born in greece , ii ) who were cooperative for oral clinical examination , iii ) who had not taken antibiotics for 15 days prior to the examination , and iv ) whose parents had returned their written informed consent and a completed questionnaire . among the 936 children who were initially eligible , 814 fulfilled the inclusion criteria and were included in the study . no dental care was routinely offered to these children , and there was no water fluoridation in this area . this was a cross - sectional study , and the protocol was approved by the ethics committee of the school of dentistry , university of athens . a letter explaining the procedures , a consent form , and a questionnaire were sent to the parents . the questionnaire consisted of closed - type questions regarding the family , demographic and socioeconomic factors , general health , oral hygiene and dietary behaviour of the child . parents with an immigrant background and a language barrier were assisted by the child s teacher when filling out the forms . the oral examination was performed in the classroom by three calibrated examiners , under a light source , using a dental mirror and a probe . the level of oral hygiene was estimated with the visible plaque index ( vpi ) , and the percentage of tooth surfaces with plaque was calculated for each child . caries was recorded as  cavity in the dentin and/or enamel  according to who criteria21 after visual inspection of the smooth surfaces and visual and tactile inspection of the pits and fissures . missing teeth were scored only if it was verified that the loss was due to caries . the presence of white spot lesions ( wsl ) , chalky white spots with unbroken surfaces , was recorded separately . no radiographs were taken . to assess the degree of inter - examiner agreement , 20 children were examined by each of the 3 examiners on the same day . the degree of intra - examiner agreement was established through an examination of 20 children by each examiner , and the procedure was repeated after 4 weeks . the mean inter - examiner and intra - examiner kappa values were k=0.89 and k=0.86 , respectively . mutans streptococci levels were estimated by sampling the upper anterior teeth with a cotton swab according to the protocol proposed by twetman and grindefjord.22 the swab was rolled on a dentocult sm strip ( orion diagnostica , helsinki , finland ) and incubated at 37c for 48 hours . the readings were performed by a single examiner , and 30 strips were reassessed after 15 days storage at 4c . buffer capacity was categorized as high / medium or low using a dentobuff strip ( orion diagnostica ) . unstimulated saliva was collected from the floor of the mouth with a pipette and placed on the strip ; the color changes were registered after 5 minutes . the intra - examiner reliability was k=0.87 for the buffer test and k=0.82 for the ms test . the scored data from the clinical examinations and the questionnaire were entered in the cariogram software . the chance to avoid caries over the next 12 months salivary secretion rate  was omitted as a variable , because it was considered difficult to adequately determine the stimulated saliva flow in this age group . moreover , the scores described in the cariogram manual for adults were modified to fit the present age group , as shown in table 1 . for example ,  previous caries experience  was scored in only two groups : those having caries and those who were caries free . any existing systemic disease was taken into consideration only if it directly or indirectly influenced the caries process ( asthma , diabetes , heart problems ) . the content of unfavorable carbohydrates in the diet ( muffins , cookies , chocolate , honey , marmalade , juice , candies , beverages and sweetened yogurt ) was extracted from the questionnaire . the diet frequency was modified by merging two categories into one and taking the frequency of 45 meals / day as normal for the age group . medium and high buffer capacity scores were incorporated into one group . in the  clinical judgment  section of the cariogram was finally grouped in three levels : low chance 0%20% ( high caries risk ) , moderate chance 21%60% ( moderate caries risk ) , and high chance 61%100% ( low caries risk ) . all data were processed by stata software ( stata 9 , stata corp lp , texas , usa ) . in addition to descriptive statistics , multivariate regression analysis was used to associate the cariogram variables with caries risk . descriptive data for the total material and the different age groups are presented in table 1 . the caries prevalence for all children was 30% , increasing from 13% in the youngest age group to 43% among the 5- to 6-year - olds . non - cavitated initial lesions ( wsl ) were recorded in 26% of the children . the vast majority ( 83% ) reported unfavorable dietary habits ( 3 intakes of sweets per day ) ; this figure was fairly stable in the different age groups . the questionnaire revealed that 62% of the 2- to 3-year - old children were exposed to systemic or topical fluoride ; this value increased to 96% among the 5- to 6-year - old children . less than satisfactory oral hygiene was recorded in 67% of all children and 23% displayed poor oral hygiene . the saliva tests showed that less than 17% had moderate or high counts of mutans streptococci and that 26% displayed impaired buffer capacity . the cariogram profiles showed that 26% , 65% and 9% of all children were assessed with high , moderate and low caries risk , respectively . to explore which of the cariogram variables best explained the caries risk levels , multivariate linear regression analysis models were calculated for the total study group ( table 3 ) and for the different age groups . for the total sample , the most significant risk variables were insufficient fluoride exposure and the presence of white - spot lesions , followed by the previous caries experience . when regression analysis was performed for the different age groups , the most significant variable for the 2- to 3-year - olds was insufficient fluoride exposure ( r=0.93 , = 0.31 , p<.001 ) . for the 3- to 4-year - olds , the presence of dental plaque ( r=0.91 , = 0.71 , p<.001 ) was most prominent , while for the 4- to 5- ( r=0.89 , = 0.163 , p<.001 ) and 5- to 6-year - olds ( r=0.91 , =0.2 , p<.001 ) , the presence of white - spot lesions showed the strongest association . the present study was undertaken to gain information about the caries risk profiles of 2-to 6-year - old greek children . the cariogram is based on the interpretation of data from numerous clinical studies on adults.23 consequently , the scoring of some of the present variables was modified to fit this young age group . two previous studies have used the cariogram in preschool children,12,13 one of which used modified variables.12 the accounting for age is most likely a key factor explaining the validity of the cariogram as a predictive tool in caries risk assessment models . the clinical examinations and scoring procedures displayed high inter- and intra - examiner agreements ; the results should therefore be regarded as reliable . whether the data from the questionnaires reflect the full truth may , however , always be debated . the large size of the present study group allowed sub - grouping with respect to age , which provided some novel and interesting information . the main results showed that 26% of the total sample had a high risk of developing caries within the coming year . in the youngest age group , the proportion of high - risk children was even higher ( 36% ) but still somewhat lower than previously reported among swedish 2-year - olds.20 the present study was , however , the first to apply multivariate regression analysis to explore the various cariogram variables in preschool children , although a similar model was previously used for young adults.15 the regression model explained 88% of the risk variability , and an apparent age - dependent shift in the results was demonstrated . the strongest caries risk variable for the 2- to 3-year - olds was insufficient fluoride exposure , whereas neglected oral hygiene was most marked for children between 3 and 4 years old . thus , emphasizing daily supervised tooth brushing with fluoridated toothpaste is of paramount importance for the youngest individuals residing in a non - fluoridated area and without access to regular dental care . the best form of delivering fluoride to this age group is through self - applied toothpaste and professional topical applications.24,25 the finding that previous caries experience and the presence of white - spot lesions were strong markers of caries risk , especially for children over 4 years old , was in agreement with conclusions from previous studies and systematic reviews.1,4,26 thus , parental education on detecting wsl and seeking early preventive dental care in young children is likely an important measure to prevent and control caries.27 furthermore , a review by thenisch et al suggested that the level of salivary mutans streptococci is a strong risk factor for caries.28 a recent study has also shown that the quantification of mutans streptococci levels is the most important salivary variable in cariogram predictions.29 interestingly , buffer capacity was a significant caries risk determinant in all of the models except for those applied to the 3- to 4-year - old children . the role of buffer capacity in young children remains to be comprehensively characterised.6 because the association with caries is subject to doubt , the buffer capacity of saliva is not considered as a sole accurate diagnostic method for caries detection in young children.30 the diet content of fermentable carbohydrates has not previously been applied in cariograms performed among preschool children . the frequency of carbohydrate - containing meals is generally considered an important factor for caries risk , but in this analysis , the dietary content of sugar was not among the primary caries risk variables . several previous studies have demonstrated a correlation between the consumption of fermentable carbohydrates and caries , especially in the absence of oral hygiene and fluoride use.31 although there is no general consensus on a safe amount of cariogenic food intake,32 the frequent consumption of fermentable carbohydrates has been associated with high mutans streptococci levels33 in preschool children , as well as with high caries risk.4,26 a high level of carbohydrate consumption is deleterious not only for oral health but also for the general health of the individual , because of the risk that unhealthy dietary habits will persist throughout adulthood.34 the present study will form the basis for a suitable preventive program to be implemented for greek children early in life . the findings suggest that the preventive program should be focused on the regular use of fluoridated toothpaste and professional fluoride varnish applications rather than extensive dietary counselling . furthermore , parental detection of white - spot lesions as well as regular check - ups and treatment should be strongly encouraged . high caries risk was found for 26% of the children examined , whereas 9% exhibited low caries risk . the most significant caries risk variables were insufficient fluoride exposure and the presence of white - spot lesions . insufficient fluoride exposure had the strongest impact for the 2- to 3-year - old children , while impaired oral hygiene had the strongest impact for those aged 34 years , and the presence of white - spot lesions was most important among children over 4 years old .
objective : to assess the caries risk profiles in 2- to 6-year - old greek children using a computer - based program and to evaluate the contribution of various risk factors.methods:the study group consisted of 814 preschool children . a questionnaire on family , demographic and socioeconomic factors , general health , oral hygiene and dietary behavior 
 was completed by the parents . 
 children were examined for cavitated and white - spot lesions ( wsl ) . 
 salivary mutans streptococci ( ms ) and buffer capacity were estimated . 
 caries risk profiles were assessed with cariogram.results:cavitated lesions were found in 30% of the children ; wsl were found in 26% of those included . 
 ms and low buffer capacity were detected in 28% and 26% of the children , respectively . 
 the majority ( 70% ) displayed neglected oral hygiene . 
 based on the questionnaires , 83% of the children had a cariogenic diet , and 17% did not use any form of fluoride . 
 the cariogram revealed that 26% of the children had high caries risk , while only 9% exhibited low caries risk . 
 the most significant caries risk variables , determined by regression analysis ( r2=0.88 ) , were insufficient fluoride exposure ( =0.160 ) and the presence of wsl ( = 0.159).conclusions : one - fourth of the children were categorised as high caries risk . 
 the presence of wsl and lack of fluoride exposure were the most significant caries risk determinants .