The Effect of Dairy Products Intake on Dental Caries across Adolescent Females in Al Thahab Al Abyedh Village Baghdad

Journal of Research in Medical and Dental Science
eISSN No. 2347-2367 pISSN No. 2347-2545

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Research - (2020) Volume 8, Issue 7

The Effect of Dairy Products Intake on Dental Caries across Adolescent Females in Al Thahab Al Abyedh Village Baghdad

Sarah M Khammas* and Ahlam T Mohammed

*Correspondence: Sarah M Khammas, Department of Pedodontics and Preventive Dentistry/College of Dentistry/University of Baghdad, Iraq, Email:

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Background: Milk is an important part of human diets and consideration has been given for the possibility that the dairy food intake could help in preventing oral health problems. This study aimed to estimate the effect of milk and other dairy products on the dental caries and plaque among the adolescents.

Materials and Methods: The study subjects were 405 adolescent females from the secondary school in Al-Thahab Al-Abyedh village aged 13-18 years. The information on the dairy intake was assessed by using a self-administered food frequency questionnaire for the adolescents. To represent the dairy products consumption clearly, it was divided into three levels. The dental caries and plaque were assessed by the visual and tactile examination using the dental mirrors and community periodontal index probes.

Results: The mean plaque index value among 13-15 years was found to be higher than 16-18 years females (0.951, 0.940) respectively but with no statistical difference (P>0.05). The means of (DS, MS, FS, DMFS and DMFT) were lower among the younger group. Significant differences were detected among the yogurt consumption levels regarding the mean of plaque index specifically between the low and high levels, whereas no significant differences among all levels of dairy intake and the caries experience.

Conclusions: These data suggested that no differences were occurred between the levels of dairy intake and the dental caries. Nevertheless, a high level of yogurt intake might be associated with lower prevalence of the dental plaque among the adolescents.


Adolescent, Baghdad, Dairy products, Dental caries


The diet and oral health relationship are intriguing [1]. Milk is an important part of human diets and consideration has also been given for the possibility that the intake of dairy food might help to prevent oral health problems [2]. It contains nutrients such as calcium, casein, phosphate and lipid that might be linked to the anticariogenic properties, the underlying mechanisms include buffering, reducing the bacterial adhesion, salivary stimulation, reducing the enamel demineralization in addition to promoting the remineralization of enamel by calcium and phosphate ions and casein. The cario-static impact of milk and/ or its products might be the result of the effects mentioned in addition to the presence of biologically active peptides within the protein fraction or that presented in the naturally occurring probiotics [3]. In the enamel slab studies (both the in vitro and in vivo) showed that the bovine milk had little potential to induce the demineralization of enamel and it could remineralize the previously demineralized enamel [4].

Several previous epidemiological studies have shown that the consumption of milk among the children and adolescents was associated with a lower caries experience. Petridou et al. stated that a negative association was found between the dairy products and dental caries [5]; Głabska et al. revealed that a reduction in the dental caries coefficient was due to the cheese consumption [6]. Moreover, Lempert et al. suggested that the high dairy products consumptin as well as the consumption of other dairy components such as dairy calcium, casein and whey might be a predictor for the lower caries risk at the level of DMFS, besides dairy intake could help in the prevention of the dental decay development in the young age [7]. In contrast, Marshall et al. found that milk had a neutral effect concerning the dental caries [8].

Although many studies addressed the relationship between the dairy products consumption and the dental caries. Yet, no previous Iraqi study has been carried out regarding the effect of milk and/ or dairy products on the dental caries. This study aimed to assess the effect of dairy intake on the dental caries and plaque across the adolescent females in Al-Thahab Al-Abyedh village.


This cross-sectional research was carried out among the secondary school females aged 13- 18 years old in Al-Thahab Al-Abyedh village/ Baghdad during the period from November 2019 till February 2020. The permission for performing this research was established from the ethics committee of the faculty of dentistry, Baghdad University (2019).

The clinical examinations were performed using dental mirrors and community periodontal probes (CPI probe). A portable head lamp light was used to provide a constant source of light. Dental plaque was measured using Silness et al. plaque index (1964) [9], while the dental caries was evaluated according to WHO criteria [10]. The dairy intake was self-reported using the “Youth and Adolescent food frequency questionnaire (YAQ)” [11] to estimate the habitual dairy intake over the previous year, which was based on “Willett food frequency questionnaire” [12,13]. The questionnaire was translated to Arabic by the Arab Board of Health Specialization. The consumption categories of dairy intake were classified as seen in Table 1. Data analysis had been accomplished by the SPSS program (version 21) using independent two-sample T-test, one-way analysis of variance (ANOVA) and a post-hoc test (Games-Howell test). The level of significance (P value) which is less than the 0.05 was considered statistically significant and the P value of less than 0.01 was considered statistically high significant.

Dairy products Consumption category
Low Moderate High
Milk 0-4 glasses/m 2-7 glasses/w >1 glass/d
Yogurt 0-3 cups/m 1-6 cups/w ≥ 1 cup/d.
Cheese 0-4 slices/m 2-7 slices/w >1slice/d

Table 1: The consumption categories of the dairy products.


In this study the total sample involved 405 female students aged (13-18) years old; then the age group was divided in two groups (13-15) and (16-18) years old. The descriptive and statistical test of the mean of plaque index (PlI) between the two groups is illustrated in Table 2, the mean of plaque index for 13-15 years was higher than that for 16-18 years (0.951, 0.940) respectively. Yet, the difference was not significant statistically (P>0.05). The caries experiences among the subjects were represented by (DS, MS, FS, DMFS and DMFT) have been shown in Table 3. The means of dental caries variables were higher among 16-18 years students than the other group and the differences were highly significant in (DS, DMFS and DMFT), significant for MS and non-significant for the FS score. As seen in Table 4, no significant differences were found among the different levels of milk and cheese consumption regarding the means of plaque index, while significant differences were exist among the three levels of yogurt consumption regarding the means of plaque index. According to the statistical test using Games-Howell test, the significant difference was between the low and high levels of yogurt consumption as seen in Table 5. Lastly, no significant differences at the three levels of dairy intake and caries experience (DS, MS, FS, DMFS and DMFT) as illustrated in Table 6.

Variable Age (years) N Mean ± SE T df P value
PlI 13-15 207 0.951 0.023 0.295 370.487 0.768
16-18 198 0.94 0.031

Table 2: Descriptive and statistical test of plaque index between the age groups.

Variables Age (years) T df P value
13-15 16-18
Mean ±SE Mean ±SE
DS 2.623 0.241 3.939 0.399 2.825 325.923 0.005**
MS 0.362 0.108 0.798 0.135 2.525 381.373 0.012*
FS 0.522 0.11 0.717 0.101 1.309 401.447 0.191
DMFS 3.507 0.3 5.455 0.421 3.771 359.138 0.000**
DMFT 2.097 0.152 3.293 0.182 5.039 387.456 0.000**

Table 3: Descriptive and statistical test of caries experience between age groups.

Dairy products Variable Low Moderate High F P
Mean ±SE Mean ± SE Mean ± SE
Milk PlI 0.945 0.025 0.943 0.033 0.962 0.063 0.024 0.976
Yogurt PlI 1.011 0.029 0.923 0.041 0.892 0.031 4.131 .017*
Cheese PlI 0.977 0.026 0.927 0.034 0.886 0.051 1.657 0.192

Table 4: Descriptive and statistical test of plaque index among dairy intake levels.

Multiple Comparisons
Dairy Product Dependent Variable (I) Trans (J) Trans Mean Difference (I-J) P value
Yogurt PlI Low Moderate 0.088 0.196
High 0.119 0.016*
Moderate High 0.031 0.819

Table 5: Multiple comparisons test between the yogurt intake levels and plaque index.

Dairy products Variables Low Moderate High F P
Mean ±SE Mean ±SE Mean ±SE
Milk DS 3.144 0.3 3.565 0.414 3.042 0.713 0.366 0.694
MS 0.537 0.104 0.605 0.168 0.833 0.389 0.343 0.71
FS 0.607 0.104 0.685 0.111 0.375 0.168 0.442 0.643
DMFS 4.288 0.341 4.855 0.45 4.25 0.801 0.508 0.602
DMFT 2.626 0.16 2.798 0.205 2.667 0.42 0.205 0.814
Yogurt DS 2.952 0.284 2.91 0.43 3.705 0.441 1.329 0.266
MS 0.545 0.143 0.567 0.19 0.607 0.131 0.053 0.948
FS 0.539 0.094 0.552 0.128 0.717 0.143 0.658 0.518
DMFS 4.036 0.362 4.03 0.501 5.029 0.462 1.789 0.169
DMFT 2.539 0.186 2.627 0.302 2.838 0.19 0.646 0.525
Cheese DS 3.55 0.383 3.2 0.35 2.549 0.326 1.232 0.293
MS 0.517 0.115 0.64 0.16 0.634 0.223 0.244 0.784
FS 0.579 0.086 0.784 0.183 0.437 0.118 1.345 0.262
DMFS 4.646 0.412 4.624 0.42 3.62 0.437 1.104 0.332
DMFT 2.732 0.183 2.768 0.208 2.38 0.244 0.657 0.519

Table 6: Descriptive and statistical test of caries experience among the dairy intake levels.


This is the first research that investigates the effect of the various consumption levels of milk, yogurt and cheese with the mean of plaque and dental caries in adolescent females living in Al- Thahab Al-Abyedh village. The mean plaque index was slightly higher in the younger age group, statistically these differences were not significant. However, they all were in good oral hygiene (0.1-0.9) according to the criteria of Silness et al. [9]. This agrees with Bendoraitienė et al. who noted that more than 60% of the girls were in good oral hygiene [14]. In contrast to Yazdani et al.who found that the majority of the adolescents were of poor oral hygiene [15]. This may be due to the accumulation of plaque depends on oral self-care practices, professional plaque control and other local factor like crowding of the teeth [16]. The mean values of all the variables (DS, MS, FS, DMFS and DMFT) were higher among 16-18 years students than 13-15 years. The accumulative as well as the irreversible nature of dental decay may be attributed to this finding [17]. Other factors relating to the hormonal changes that modify the biochemical composition and the overall flow rate of saliva in many ways by the fluctuations of the hormone level throughout events like puberty and menstruation [18]; in addition to the increased stress for the pre-college students could affect their eating habits [19]. Further more, changes in the dental behavior as the parents become gradually less actively involved in the dental caring of their teenagers. DS scores were the highest scores than FS and MS, this may be because of the lower access to the dental clinics.

significance regarding the mean of plaque score. This may be since yogurt contains probiotics as well as whey protein which might have beneficial effects within the oral cavity. The probiotics positive effect was more likely related to the displacement of streptococcus mutans and other cariogenic bacteria from their binding sites on the dental surfaces and in the oral biofilms [20]. While whey protein might enhance the immune system function and inhibit the plaque formation Besides, whey protein is found in yogurt more than that in cheese as most of it is lost during ripping [21]. A previous study found that the consumption of ≥3 servings/day of milk products was significantly associated with low plaque score among 606 Danish adults aged 65 and older [22]. Where as Tsitaishvili et al. did not find any association between the dairy intake or other eating habits with plaque score [23]. The present study shows no significant differences regarding the consumption of milk or other dairy products and the dental caries experience; this result agrees with Marshall et al. (2003) [8]. In contrast, many studies showed that low caries prevalence was associated with milk intake [5-7]. The reason may be due to dental decay is considered as a multifactorial disease that developed through the interaction of the three main factors with the presence of time, namely, the oral microorganism (acidogenic bacteria), susceptible host (the physical and chemical properties of saliva as well as the tooth quality) and the substrate (fermentable carbohydrates) [3]. In addition to the factors dealing with the oral hygiene habits like those of teeth brushing, flossing, and visiting the dentist. Also, the differences in the age group and methodology that had been used could affect the result of the studies.


This study has found that the high yogurt consumption may decrease the prevalence of plaque within the adolescents. Nevertheless, no significant effect of dairy intake on dental caries was found. Additional studies, particularly, longitudinal studies and controlled intervention trials are warranted to exactly understand how the dairy consumption affects the oral health outcomes.


Author Info

Sarah M Khammas* and Ahlam T Mohammed

Department of Pedodontics and Preventive Dentistry/College of Dentistry/University of Baghdad, Iraq

Citation: Sarah M Khammas, Ahlam T Mohammed, The Effect of Dairy Products Intake on Dental Caries across Adolescent Females in Al Thahab Al Abyedh Village Baghdad, J Res Med Dent Sci, 2020, 8 (7): 32-36.

Received Date: Sep 27, 2020 / Accepted Date: Oct 14, 2020 / Published Date: Oct 21, 2020