Home | About us | Editorial board | Search | Ahead of print | Current issue | Archives | Submit article | Instructions| Reviewers

Login 
  Home Print this page Email this page Small font sizeDefault font sizeIncrease font size Users Online: 589    
     


 
Table of Contents   
ORIGINAL ARTICLE
Year : 2018  |  Volume : 8  |  Issue : 1  |  Page : 48-55
Relationship between physicochemical properties of saliva and dental caries and periodontal status among female teachers living in Central Iran


1 Department of Dental Public Health, Oral and Dental Disease Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
2 Department of Nutrition, Nutrition and Food Security Research Center, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
3 Department of Clinical Biochemistry, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran

Date of Submission30-Oct-2017
Date of Acceptance18-Dec-2017
Date of Web Publication22-Feb-2018

Correspondence Address:
Dr. Ali Golkari
Department of Dental Public Health, School of Dentistry, Ghomabad, Ghasrodasht St., Shiraz
Iran
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jispcd.JISPCD_391_17

Rights and Permissions

   Abstract 

Objectives: There are inconsistent data about the association between saliva properties, dental caries, and periodontal status. In this study, we tried to examine the association between dental caries and periodontal status with salivary viscosity, flow rate, pH, and buffering capacity in adults.
Methods: In the present cross-sectional study, 450 female teachers were randomly selected from schools located in Yazd, Iran. Oral examinations were conducted, and unstimulated saliva samples were collected. Salivary viscosity, flow rate, pH, and buffering capacity were assessed. The salivary physicochemical properties were compared among teachers with different types of oral health. Analyses were done using the Statistical Package for the Social Sciences version 16.
Results: In total, 431 female teachers aged 40.45 ± 8.18 years were included in the study. Salivary flow rate, buffering capacity, pH, and viscosity, community periodontal index status were not significantly different in participants with and without tooth caries. There was a reverse linear association between salivary pH and flow rate with the decayed, missed, and filled teeth index (P < 0.05). The saliva buffering capacity was not significantly related to dental properties. Those with bleeding on probing had lower salivary pH, and buffering capacity compared to those with healthy gum. However, the salivary resting flow rate was not different in participants with bleeding on probing and healthy participants.
Conclusion: Based on our results, saliva properties might be important predictors in oral health status. This means that any change in saliva combination might affect periodontal and dental diseases. Future prospective studies are recommended to confirm these results.


Keywords: Dental caries, periodontal index, physicochemical properties, saliva


How to cite this article:
Hosseini-Yekani A, Nadjarzadeh A, Vossoughi M, Reza JZ, Golkari A. Relationship between physicochemical properties of saliva and dental caries and periodontal status among female teachers living in Central Iran. J Int Soc Prevent Communit Dent 2018;8:48-55

How to cite this URL:
Hosseini-Yekani A, Nadjarzadeh A, Vossoughi M, Reza JZ, Golkari A. Relationship between physicochemical properties of saliva and dental caries and periodontal status among female teachers living in Central Iran. J Int Soc Prevent Communit Dent [serial online] 2018 [cited 2019 Jul 23];8:48-55. Available from: http://www.jispcd.org/text.asp?2018/8/1/48/226021



   Introduction Top


Saliva is a body fluid secreted by salivary glands which essentially contains water, proteins, glycoproteins, electrolytes, small organic molecules, and compounds that is transported from the bloodstream.[1],[2] It plays an important role in maintaining oral health due to its biological functions such as food swallowing, lubrication of oral tissues, and washing off food debris.[3] Saliva also helps maintaining the integrity of dental tissues and especially helps in prevention of dental caries.[2] Furthermore, it has three specific roles in the oral cavity. First, it protects the enamel against demineralization caused by the acids. Second, it facilitates the remineralization of incipient caries and then the last one it has some antimicrobial functions.[3],[4]

Saliva can be assessed by some characteristics, such as flow rate, buffering capacity, hydrogen-ion concentration (pH), and its consistency.[3],[5],[6],[7],[8],[9] Alteration in any of these characters may increase the risk of caries.[10] Saliva can buffer acids, and this ability is essential for maintaining pH values in the oral cavity. Bicarbonate ions play an important role in determining the pH and buffering capacity of saliva that can help protect teeth against attack from acids which are produced by bacteria.[11] Dental caries is probably the most common consequence of lacking saliva.[12]

The reduction in salivary flow rate may cause severe caries and mucosal inflammations.[13],[14] Individuals with impaired saliva flow rate often show higher risk of caries or the susceptibility to have caries.[15],[16] However, the studies were inconsistent in their results particularly in those with normal flow rate.[2] Moreover, an increase in the antioxidant activity of the saliva may lead to the increase in the suspension of proteins and cariogenic activity.[17] Some documents claim that buffering capacity of saliva can modify the erosive process in teeth.[12],[18] Saliva also can affect periodontal status.[19],[20],[21] In a study about salivary antioxidant capacity, it was found that women had significantly lower total antioxidant status compared to men, regardless of periodontal health. Periodontal damage was also associated with reduced salivary antioxidant status.[22] In addition, inflammatory processes in the mouth, such as periodontal disease, have been related to the decrease of saliva antioxidants.[21] Although challenges remain ahead, saliva fluid is useful for future application to diagnose periodontal diseases and to prognosticate periodontal treatment outcomes.[20],[23] As studies examined the association between saliva properties and dental caries and periodontal status were conflicting and a limited number of studies have been conducted investigating such association in the Middle East, in the present study, we tried to explore such association in a large sample of female adults controlling the maximum number of possible confounders.


   Materials and Methods Top


Study design and sample size

This was a cross-sectional study that was conducted from September 2016 to March 2017 on 20-to 60-year-old female teachers working in schools of the city of Yazd in Central Iran. This study was in the context of a larger cross-sectional study which is explained somewhere else.[24] The permission was obtained from the Ethics Committee of Shiraz University of Medical Sciences and the Yazd province education organization. The study protocol for the present analysis was approved by the Research Council of Shiraz University of Medical Sciences, and all participants filled an informed consent before entering the study (approval no: 94-01-03-9223). Randomized cluster sampling method was used in the study, and 450 teachers were invited. The minimum required sample size was calculated to be 151 according to the mean decayed, missed, and filled teeth (DMFT) of adults in a similar study,[25] the accuracy of 1, and α = 0.05. However, as the cluster randomization was used for sampling, we had enough resources and the study had objectives other than the present study we tried to include 450 participants.

The inclusion criteria were to be a female teacher of chosen schools, and then, participants with diabetes mellitus and pregnant women were omitted. Information on general characteristics as well as education, economic status, physical activity, dietary food and supplement intake, and self-assessment of oral hygiene condition were obtained using self-administered questionnaires. The anthropometric measurements were conducted by a trained nutritionist, and all participants were then visited by a general dentist for assessment of dental caries to observe their dental status and gingival status. After that collecting, the saliva sample was done at their schools.

Anthropometric measurements

In all cases, anthropometric parameters (height, weight, waist circumference, and hip circumference) were measured by a nutritionist. Weight was measured using a digital scale (SECA, model 813) with an accuracy of 100 g while the participant had minimum cloths on. Height was measured using a tape measure mounted on the wall with an accuracy of 0.5 cm while the participants were in the standing position, and body mass index (BMI) was calculated by dividing weight (in kg) by height squared (in square meters).

Oral examination

The oral examination was carried out inside of each school by one general dentist to minimize the between assessor variabilities. The dentist was trained for all the examinations done in the present study. Teachers sat on a chair, and their teeth and gingiva were examined by means of a headlight and disposable dental mirror, dental probes, and tongue blades. Samples' DMFT and community periodontal index (CPI) were assessed using the WHO criteria.[26]

Collecting saliva samples

Teachers were told to be present at school between 8:00 and 10:00 in the morning to collect their saliva. They were asked to brush their teeth without any saliva stimulator, and they were fast from 2 h before collecting the samples.[27] Teachers were asked to hold their head down, not swallow, and split all their saliva in a collecting cap for 10 min. Their salivary glands should not be stimulated by any stimulator to collect resting saliva.

Saliva viscosity

The consistency of saliva was obtained by visual examination. Healthy saliva is watery and clear. In a case with low production rate of saliva, it becomes frothy, stringy, bubbly, or very sticky.[28] Saliva samples were categorized to normal (watery) and high viscosity (sticky or bubbly) groups based on this visual examination.

Saliva flow rate

The collected saliva in caps was weighted by a digital scale (model: Precision Balance M.T Electronic Balance K-500BH, 0.01–500 g scale, made in Hong Kong) before and after saliva collection.

Salivary pH and buffering capacity

Salivary pH was checked right after collecting saliva using a pH meter at school. After that, 1 ml of 0.1 N hydrochloric acid (HCL) was added to 1 ml of saliva for calculating the buffering capacity according to Ericsson method.[17] For assessing an accurate range of pH, a digital pH meter which shows up to two decimal places was used (model no: AZ8686 made in Taiwan).

Assessment of covariates

Other variables were also collected by administration of self-administered questionnaires. The following data were collected: age (in years), marital status (single/married), participants' education (college/bachelor's degree/master's degree or higher), menstruation status (yes/no), oral contraceptive use (yes/no), history of cardiovascular diseases, history of type 2 diabetes, cardiovascular diseases, metabolic syndrome or other chronic diseases (yes/no), family history of diabetes (yes/no), and Vitamin D or multivitamin-mineral supplement use (yes/no). Economic status was assessed using a 9-item self-administered questionnaire. In the questionnaire, we asked about the number of family members, husband's occupation, the head of household (husband/herself/other family members), house ownership (owner/tenant), house type (apartment/house), number of bedrooms in the house, car ownership (yes/no), number of cars owned by the family, and family income per month. Data on physical activity were obtained using the international physical activity questionnaire (short format).[29] The information gathered from this questionnaire was converted to metabolic equivalent hours per week and participants were placed in two categories (sedentary and active). The usual toothbrushing style (lower than once a day/once a day/twice a day/more than twice a day) was also asked in the questionnaire.

Statistical analysis

The normal distribution of quantitative data was checked using Kolmogorov–Smirnov status.

The comparison of quantitative and qualitative variables between participants with and without tooth decay was examined using independent samples Student's t and Chi-square tests, respectively.

The linear association of saliva pH, flow rate, and buffering capacity with number of decayed (D), missed (M), and filed (F) teeth and also the DMFT index was assessed using the linear regression in crude and two multivariable-adjusted models. Age was adjusted in the first model, and other possible effect modifiers including BMI, physical activity level (sedentary/active), menstruation status (yes/no), education (college/bachelor's degree/master's degree), marriage status (single/married), economic status (low/middle/high), oral contraceptive use (yes/no), history of chronic diseases (yes/no), and toothbrushing (lower than once a day/once a day/twice a day/more than twice a day) were additionally adjusted in the second model.

The comparison of salivary pH, buffering capacity, and flow rate across periodontal status was assessed using analysis of covariance with Bonferroni correction in the same multivariable-adjusted models. The statistical analyses were conducted using the Statistical Package for the Social Sciences (SPSS, version 16.0 for Windows, 2006, SPSS, Inc., Chicago, IL, USA). P < 0.05 was considered as statistically significant.


   Results Top


In total, 431 participants (95.8%) aged 40.45 ± 8.18 years had complete data to be entered to be included in the current analysis; of these, 163 participants (37.8%) did not have any decayed tooth and 268 participants (62.2%) were diagnosed with at least one decayed tooth. Participants with at least one decayed tooth were younger (P = 0.007) and had a lower number of missed teeth (P = 0.004) compared to those without any decayed tooth. Furthermore, a lower proportion of this group experienced menstruation (P = 0.038). This is while the number of DMF teeth was significantly higher (P < 0.001) in participants with decayed teeth compared to those without any decayed teeth. Participants with and without decayed teeth were not significantly different according to BMI, filled teeth, salivary flow rate, buffering capacity, pH and viscosity, CPI status, marriage status, education status, economic status, OCP use, physical activity, disease history, and toothbrushing habit [Table 1].
Table 1: General characteristics of study participantsa

Click here to view


The linear association between salivary physic-chemical properties and number of DMFT as well as the DMFT index is represented in [Table 2]. The analyses revealed that there is a linear reverse association between salivary pH and the number of decayed teeth (β = −0.456, P = 0.016), filled teeth (β = −0.488, P = 0.048), and DMFT index (β = −1.064, P = 0.002) in the crude analysis. These associations remained significant after adjustment for age in the first model (decayed teeth, β = −0.419, P = 0.026; filled teeth, β = −0.517, P = 0.037; and DMFT index, β = −1.081, P = 0.002). However, the association was only remained significant for DMFT index after further adjustment for BMI, physical activity level (sedentary/active), menstruation status (yes/no), education (college/bachelor's degree/master's degree), marriage status (single/married), economic status (low/middle/high), oral contraceptive use (yes/no), history of chronic diseases (yes/no), and toothbrushing (lower than once a day/once a day/twice a day/more than twice a day) in the second model (β = −0.977, P = 0.006). The salivary flow rate was also inversely associated with the number of missed teeth and the DMFT index either in crude (filled teeth, β = −1.343, P = 0.030 and DMFT index, β = −2.454, P = 0.004) and fully adjusted models (filled teeth, β = −1.473, P = 0.022 and DMFT index, β = −2.460, P = 0.006). The saliva buffering capacity was associated with all dental properties neither in crude nor in multivariable-adjusted models [Table 2].
Table 2: The linear association between saliva parameters and the number of decayed, missed, and filled teeth and the decayed, missed, and filled teeth index in crude and multivariable-adjusted modelsa

Click here to view




It was revealed that salivary pH is significantly different based on CPI categories either in crude and multivariable-adjusted models [Table 3]. Between-group comparisons revealed that those with bleeding on probing had a significantly lower salivary pH and buffering capacity (P < 0.001) compared to other CPI status groups. Although the salivary resting flow rate was not different in participants with bleeding on probing and healthy participants, those with bleeding on probing had a significantly lower saliva flow rate compared to participants with pocket depth of 3–5 mm and those with either blooding on probing and calculus (P < 0.001). The other between-group comparisons of salivary physic-chemical properties according to CPI status are provided in [Table 3].
Table 3: Mean saliva parameters based on the community periodontal index of treatment need community periodontal index in crude and multivariable-adjusted models1

Click here to view



   Discussion Top


The present cross-sectional study on 431 adult female teachers showed that there is a linear inverse association between salivary pH and the DMFT index. We also found that the salivary flow rate is negatively associated with the number of missed teeth and the DMFT index. We also found that salivary pH, flow rate, and buffering capacity are significantly different in participants with different CPI status.

The present study was the first study which tried to examine the association between salivary properties and dental caries and periodontal status after adjusting for the maximum number of potential confounders. Furthermore, we tried to recruit a large number of participants to increase the statistical power of the study. There are also some limitations that should be considered while interpreting our results. Due to the cross-sectional nature of the current project, causality cannot be inferred and prospective observational studies are highly needed to confirm our findings. In addition, although we have tried to control for several confounding variables in our analyses, residual confounding from unknown or unmeasured factors is inevitable. It should also be kept in mind that the present study was a done in a sample of female adults working in schools across the Yazd city; therefore, generalizing our findings to the Iranian adults must be considered with caution.

While the published evidence is scarce, the association between saliva physicochemical properties and dental caries had been explored in a number of studies, particularly among children.[30],[31],[32],[33],[34] For instance, a study which compared the salivary properties in caries-active and caries-free children revealed that salivary flow and pH were significantly lower in caries-active participants.[35] Furthermore, a study conducted in Medina, Saudi Arabia, showed that there is an association between low buffering capacity and higher prevalence of dental caries among children.[31] In another study published in 2014, Animireddy et al. revealed that the mean salivary flow rate, salivary pH, and salivary buffering capacity is significantly higher and the salivary viscosity is significantly lower among caries-free participants.[30] In contrast, data about the association between salivary properties and dental caries are fewer in adults. Conducting a case–control study on participants with (n = 20) and without diabetes mellitus (n = 20), Seethalakshmi et al. showed that there is a significant relationship between the diabetes mellitus and increased incidence of dental caries and periodontitis and there was also a significant reduction in the salivary pH in diabetes mellitus patients, compared to that of nondiabetic participants. Therefore, they concluded that salivary pH might be associated with dental caries in patients with diabetes mellitus. They also found an inverse association between saliva pH and DMFT index.[33] A large-scale study in 1763 American patients showed that salivary pH, flow rate, and buffering capacity are not associated with dental caries in adult patients.[36] This is while we found a reverse association between nonstimulated saliva pH and flow rate and dental caries, but the relationship was not significant for buffering capacity. A number of studies have proposed that resting pH might not be a predictor for dental decay;[37],[38] however, the studies providing such evidence are accumulating.

In the present study, we found that saliva pH and buffering capacity are lowest among participants with bleeding on probing while the saliva pH was highest in those participants who had both bleeding on probing and calculus and the buffering capacity was highest in those with pocket depth of 3–5 mm. A study published recently has shown that participants with bleeding on probing and participants with periodontal pockets >4 mm as well as clinical attachment loss with or without bleeding on probing have a significantly higher saliva pH compared to healthy controls.[39] A higher pH is associated with increased proteolytic activity in microorganisms which favors the deposition of calcium phosphate and therefore the promotion of plaque mineralization. It is also suggested by previous studies that higher salivary flow rate is significantly associated with development of periodontitis.[40] In the present study, we also found a higher saliva unstimulated flow rate in those with pocket depth of 3–5 mm and those with both bleeding on probing and calculus compared to those with just bleeding on probing; however, the difference was not statistically significant compared to healthy participants. Our results are in line with the previous studies. In the present study, we tried to include a large sample of female adults, and this large sample size led us to explore the association after controlling the maximum number of confounding variables. This is while the other studies could not take the other confounders into account.


   Conclusion Top


We found that there is a linear inverse association between salivary pH and the DMFT index. We also found the salivary flow rate is negatively associated with the number of missed teeth and the DMFT index. We also found that saliva pH, flow rate, and buffering capacity are significantly different in participants with different levels of periodontal diseases. Saliva properties are important in oral health. Changes in its physicochemical properties might negatively affect dental and periodontal status. Prospective cohort studies are highly recommended to confirm the cause and effect association for the relationships we found in the current study.

Acknowledgments

The current study was derived from a PhD thesis by A.H.Y. which was conducted under supervision of AG and advisory of AN, MV, and JZ.

Financial support and sponsorship

This study was financially supported by the Vice-Chancellery for Research, Shiraz University of Medical Sciences, Shiraz, Iran.

Conflicts of interest

There are no conflicts of interest.



 
   References Top

1.
Pandey P, Reddy NV, Rao VA, Saxena A, Chaudhary CP. Estimation of salivary flow rate, pH, buffer capacity, calcium, total protein content and total antioxidant capacity in relation to dental caries severity, age and gender. Contemp Clin Dent 2015;6:S65-71.  Back to cited text no. 1
[PUBMED]    
2.
Gao X, Jiang S, Koh D, Hsu CY. Salivary biomarkers for dental caries. Periodontol 2000 2016;70:128-41.  Back to cited text no. 2
    
3.
Islas-Granillo H, Borges-Yañez SA, Medina-Solís CE, Galan-Vidal CA, Navarrete-Hernández JJ, Escoffié-Ramirez M, et al. Salivary parameters (Salivary flow, pH and buffering capacity) in stimulated saliva of Mexican elders 60 years old and older. West Indian Med J 2014;63:758-65.  Back to cited text no. 3
    
4.
Hegde S, Thakur NS, Kohli S, Shukla V, Siddiqui A, Patel P, et al. A comparative evaluation of salivary flow rate, pH, buffering capacity, calcium and total protein levels in pregnant and non pregnant women. J Adv Med Dent Sci Res 2016;4:92.  Back to cited text no. 4
    
5.
Wright FA, Law G, Chu SK, Cullen JS, Le Couteur DG. Residential age care and domiciliary oral health services: Reach-OHT-the development of a metropolitan oral health programme in Sydney, Australia. Gerodontology 2017;34:420-6.  Back to cited text no. 5
    
6.
Khemiss M, Ben Khelifa M, Ben Saad H. Preliminary findings on the correlation of saliva pH, buffering capacity, flow rate and consistency in relation to waterpipe tobacco smoking. Libyan J Med 2017;12:1289651.  Back to cited text no. 6
    
7.
Gadbury-Amyot CC, Austin KS, Simmer-Beck M. A review of the oral health-related quality of life (OHRQL) model for dental hygiene: Eighteen years later. Int J Dent Hyg 2017:1-12.  Back to cited text no. 7
    
8.
Kumar U, Rath S. Dental management for patients in ICU. J Oral Health Community Dent 2016;10:80-6.  Back to cited text no. 8
    
9.
Tupalli AR, Satish B, Shetty BR, Battu S, Kumar JP, Nagaraju B, et al. Evaluation of the erosive potential of various pediatric liquid medicaments: An in-vitro study. J Int Oral Health 2014;6:59-65.  Back to cited text no. 9
    
10.
Messer LB. Assessing caries risk in children. Aust Dent J 2000;45:10-6.  Back to cited text no. 10
    
11.
Singh S, Sharma A, Sood PB, Sood A, Zaidi I, Sinha A, et al. Saliva as a prediction tool for dental caries: An in vivo study. J Oral Biol Craniofac Res 2015;5:59-64.  Back to cited text no. 11
    
12.
Alkhateeb AA, Mancl LA, Presland RB, Rothen ML, Chi DL. Unstimulated saliva-related caries risk factors in individuals with cystic fibrosis: A cross-sectional analysis of unstimulated salivary flow, pH, and buffering capacity. Caries Res 2017;51:1-6.  Back to cited text no. 12
    
13.
van der Reijden WA, van der Kwaak JS, Veerman EC, Nieuw Amerongen AV. Analysis of the concentration and output of whole salivary constituents in patients with Sjögren's syndrome. Eur J Oral Sci 1996;104:335-40.  Back to cited text no. 13
    
14.
Kapoor R. Effect of Antioxidant Gel on Oxidative Stress and Salivary Flow Rate in Xerostomic Patients; 2017.  Back to cited text no. 14
    
15.
Spak CJ, Johnson G, Ekstrand J. Caries incidence, salivary flow rate and efficacy of fluoride gel treatment in irradiated patients. Caries Res 1994;28:388-93.  Back to cited text no. 15
    
16.
Bidinotto AB, Martins AB, Dos Santos CM, Hugo FN, Hilgert JB, Celeste RK, et al. Four-year incidence rate and predictors of root caries among community-dwelling south Brazilian older adults. Community Dent Oral Epidemiol 2017;doi: 10.1111/cdoe.12343; [Epub ahead of print].  Back to cited text no. 16
    
17.
Tulunoglu O, Demirtas S, Tulunoglu I. Total antioxidant levels of saliva in children related to caries, age, and gender. Int J Paediatr Dent 2006;16:186-91.  Back to cited text no. 17
    
18.
Larsen MJ, Nyvad B. Enamel erosion by some soft drinks and orange juices relative to their pH, buffering effect and contents of calcium phosphate. Caries Res 1999;33:81-7.  Back to cited text no. 18
    
19.
Javaid MA, Ahmed AS, Durand R, Tran SD. Saliva as a diagnostic tool for oral and systemic diseases. J Oral Biol Craniofac Res 2016;6:66-75.  Back to cited text no. 19
    
20.
Tartaglia GM, Gagliano N, Zarbin L, Tolomeo G, Sforza C. Antioxidant capacity of human saliva and periodontal screening assessment in healthy adults. Arch Oral Biol 2017;78:34-8.  Back to cited text no. 20
    
21.
Luke R, Khan SN, Iqbal PS, Soman RR, Chakkarayan J, Krishnan V, et al. Estimation of specific salivary enzymatic biomarkers in individuals with gingivitis and chronic periodontitis: A clinical and biochemical study. J Int Oral Health 2015;7:54-7.  Back to cited text no. 21
    
22.
Sculley DV, Langley-Evans SC. Periodontal disease is associated with lower antioxidant capacity in whole saliva and evidence of increased protein oxidation. Clin Sci (Lond) 2003;105:167-72.  Back to cited text no. 22
    
23.
Giannobile WV, Beikler T, Kinney JS, Ramseier CA, Morelli T, Wong DT, et al. Saliva as a diagnostic tool for periodontal disease: Current state and future directions. Periodontol 2000 2009;50:52-64.  Back to cited text no. 23
    
24.
Shahvazi S, Nadjarzadeh A, Mehri Z, Salehi-Abargouei A. Prevalence of metabolic syndrome in adult females: Comparison between Iranian national definition and currently used international criteria. J Nutr Food Secur 2016;1:49-62.  Back to cited text no. 24
    
25.
Hessari H, Vehkalahti MM, Eghbal MJ, Murtomaa HT. Oral health among 35- to 44-year-old Iranians. Med Princ Pract 2007;16:280-5.  Back to cited text no. 25
    
26.
World Health Organization. Oral Health Surveys: Basic Methods. Geneva: World Health Organization; 2013.  Back to cited text no. 26
    
27.
Navazesh M. Methods for collecting saliva. Ann N Y Acad Sci 1993;694:72-7.  Back to cited text no. 27
    
28.
Ranganath LM, Shet RG, Rajesh AG. Saliva: A powerful diagnostic tool for minimal intervention dentistry. J Contemp Dent Pract 2012;13:240-5.  Back to cited text no. 28
    
29.
Ainsworth BE, Haskell WL, Whitt MC, Irwin ML, Swartz AM, Strath SJ, et al. Compendium of physical activities: An update of activity codes and MET intensities. Med Sci Sports Exerc 2000;32:S498-504.  Back to cited text no. 29
    
30.
Animireddy D, Reddy Bekkem VT, Vallala P, Kotha SB, Ankireddy S, Mohammad N, et al. Evaluation of pH, buffering capacity, viscosity and flow rate levels of saliva in caries-free, minimal caries and nursing caries children: An in vivo study. Contemp Clin Dent 2014;5:324-8.  Back to cited text no. 30
[PUBMED]  [Full text]  
31.
Bhayat A, Ahmad MS, Hifnawy T, Mahrous MS, Al-Shorman H, Abu-Naba'a L, et al. Correlating dental caries with oral bacteria and the buffering capacity of saliva in children in Madinah, Saudi Arabia. J Int Soc Prev Community Dent 2013;3:38-43.  Back to cited text no. 31
    
32.
Farsi N. Dental caries in relation to salivary factors in Saudi population groups. J Contemp Dent Pract 2008;9:16-23.  Back to cited text no. 32
    
33.
Seethalakshmi C, Reddy RC, Asifa N, Prabhu S. Correlation of salivary pH, incidence of dental caries and periodontal status in diabetes mellitus patients: A cross-sectional study. J Clin Diagn Res 2016;10:ZC12-4.  Back to cited text no. 33
    
34.
Vitorino R, Calheiros-Lobo MJ, Duarte JA, Domingues P, Amado F. Salivary clinical data and dental caries susceptibility: Is there a relationship? Bull Group Int Rech Sci Stomatol Odontol 2006;47:27-33.  Back to cited text no. 34
    
35.
Abbate GM, Borghi D, Passi A, Levrini L. Correlation between unstimulated salivary flow, pH and Streptococcus mutans, analysed with real time PCR, in caries-free and caries-active children. Eur J Paediatr Dent 2014;15:51-4.  Back to cited text no. 35
    
36.
Cunha-Cruz J, Scott J, Rothen M, Mancl L, Lawhorn T, Brossel K, et al. Salivary characteristics and dental caries: Evidence from general dental practices. J Am Dent Assoc 2013;144:e31-40.  Back to cited text no. 36
    
37.
Varma S, Banerjee A, Bartlett D. An in vivo investigation of associations between saliva properties, caries prevalence and potential lesion activity in an adult UK population. J Dent 2008;36:294-9.  Back to cited text no. 37
    
38.
Leone CW, Oppenheim FG. Physical and chemical aspects of saliva as indicators of risk for dental caries in humans. J Dent Educ 2001;65:1054-62.  Back to cited text no. 38
    
39.
Patel RM, Varma S, Suragimath G, Zope S. Estimation and comparison of salivary calcium, phosphorous, alkaline phosphatase and pH levels in periodontal health and disease: A cross-sectional biochemical study. J Clin Diagn Res 2016;10:ZC58-61.  Back to cited text no. 39
    
40.
Rajesh KS, Zareena, Hegde S, Arun Kumar MS. Assessment of salivary calcium, phosphate, magnesium, pH, and flow rate in healthy subjects, periodontitis, and dental caries. Contemp Clin Dent 2015;6:461-5.  Back to cited text no. 40
[PUBMED]  [Full text]  



 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

Top
Print this article  Email this article
 
  Search
 
  
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Article in PDF (517 KB)
    Citation Manager
    Access Statistics
    Reader Comments
    Email Alert *
    Add to My List *
* Registration required (free)  


    Abstract
   Introduction
    Materials and Me...
   Results
   Discussion
   Conclusion
    References
    Article Tables

 Article Access Statistics
    Viewed821    
    Printed67    
    Emailed0    
    PDF Downloaded77    
    Comments [Add]    

Recommend this journal