REV.CHIM.(Bucharest)♦67♦No. 4 ♦2016 http://www.revistadechimie.ro 821 The Comparative Evaluation of Salivary Biomarkers (Calcium, Phosphate, Salivary p H) in Cario-resistance Versus Cario-activity VASILE NICOLAE 1 , BOGDAN NEAMTU 1,2 *, OANA PICU 2 , MARIA ALEXANDRA MARTU STEFANACHE 3 , VLADIMIR SORIN IBRIC CIORANU 1 1 Lucian Blaga University Sibiu, V. Papilia, Faculty of Medicine, 10 Victoriei Blvd., 550024, Sibiu, Romania 2 CEFORATEN Clinical Hospital of Paediatrics Sibiu, 2-4 Pompeiu Onofreiu Str., 550166, Sibiu, Romania 3 Gr. T. Popa University of Medicine and Pharmacy Iasi, Periodontology Department, 16 Universitatii Str., 700115, Iasi, Romania The aim of this study is to evaluate the existence of a causal relationship between salivary parameters: calcium, inorganic salivary phosphate, salivary pH and the dental caries in study subjects. We also analyzed the relationship between these parameters and the dental status in cario-resistant and cario-active patients. Key words: calcium, phosphate, salivary pH, dental status Due to the presence of calcium and phosphate, the human saliva has a great potential in the remineralisation of carious enamel, a potential which is quite constant in the same subject and different from one subject to another. The mineral component of enamel, dentin and cement is the hydroxyapatite [Ca 10 (PO 4 ) 6 (OH) 2 ]. In a neutral p H, the hydroxyapatite is in a balance with the oral environment, saturated in Ca 2+ and PO 4 3- [1]. The demineralisation process is reversible if the p H is neutral and if there are enough Ca 2+ and PO 4 3- in the liquid environment [2]. The remineralisation process consists in the precipitation of calcium and phosphate as insoluble Calcium Phosphate which, when present in the saliva, is brought to the demineralised enamel in incipient defects resulted from surface demineralisation [3]. The optimal and correct remineralisation is impaired by certain organic substances in the saliva, like mucin whose affinity for the hydroxyapatite is known and together they form a surface pellicle which perturbs the remineralizing ionic transport. The fluoride ions facilitate the profound penetration of remineralizing ions into the demineralised defects [4]. A good oral hygiene and high buffer abilities are frequent in cario-resistant subjects versus cario-active ones who have unsatisfactory oral hygiene and buffer ability of the saliva. The decrease of salivary p H is opposed by the buffer ability of the saliva. A long persistence of a low p H can generate overwhelmed salivary buffer systems, with the precipitation of mucins and salivary proteins on the dental surface and the formation of a mucin bacterial plaque which initiates the carious process [3, 4]. We proposed the evaluation of a causal relationship between salivary parameters: calcium, inorganic salivary phosphate, salivary p H and the dental caries in study subjects. We also analyzed the relationship between these parameters and the dental status in cario-resistant and cario-active patients. * email: mihai.neamtu@ulbsibiu.ro Experimental part Materials and method The research was conducted between 2006 and 2011 on 516 child and teenager subjects from I-XII grades which were submitted to a dental examination in the school dental office. The obtained data (from alimentation questionnaire, extra-oral and oral examination, radiologic and laboratory data and the salivary concentrations of calcium, phosphate and p H) were registered in the speciality observation charts. The saliva samples were collected during the clinical examinations from each patient for the biochemical assessment of salivary p H, salivary inorganic phosphates and total salivary calcium. The saliva collection preceded the diagnosis procedures and was done after the therapy measures, by chewing a cotton roll for 5 min. The cotton roll was centrifuged and 1- 2mL of saliva was collected, permitting the biochemical evaluations. Following the literature data, we aimed therefore the correlations between the salivary concentrations of calcium, phosphate and pH to the carious lesions observed in 516 subjects [5]. Calcium Evaluation For the evaluation of the salivary calcium we used the Calcium-Arsenase III test, Konelab method. In neutral environment, in the presence of arsenase III, the calcium ions form a coloured compound. The intensity of the colour is proportional to the calcium ions concentration. In order to verify the values, we evaluated the salivary calcium also by the Hitachi 912: CALCIU SYS1 METHOD, equivalent for the quantitative evaluation of calcium in serum, plasma and urine on the Hitachi 912 system [6]. Salivary p H evaluation It is generally admitted that the saliva has a slightly acid reaction, with mean values of 6.5-7.5. The assessment of salivary p H was conducted with a paper band – standard p H indicator. The band was placed in the oral cavity in contact with saliva and the obtained colour was compared to a standard colour scale; the obtained values were registered in the personal charts of each patient.