• Meri Pavlevska Department of Pediatric and Preventive Dentistry, Faculty of Dentistry, Ss. Cyril and Methodius University, Skopje, Republic of North Macedonia
  • Elizabeta Gjorgjievska Department of Pediatric and Preventive Dentistry, Faculty of Dentistry, Ss. Cyril and Methodius University, Skopje, Republic of North Macedonia
  • Mira Jankulovska Department of Pediatric and Preventive Dentistry, Faculty of Dentistry, Ss. Cyril and Methodius University, Skopje, Republic of North Macedonia
  • Mirko Saveski Department of Pediatric and Preventive Dentistry, Faculty of Dentistry, Ss. Cyril and Methodius University, Skopje, Republic of North Macedonia
  • Bojan Poposki Department of Periodontology and Oral Pathology, Faculty of Dentistry, Ss. Cyril and Methodius University, Skopje, Republic of North Macedonia


Caries intensity, saliva, salivary urea, pH of saliva


Aim: The aim of our study was to determine and compare hydrogen ions (pH) and urea in non-stimulated saliva in patients with varying caries intensity.

Material and methods: The study involved 109 subjects from both sexes, from 12 to 15 years of age, which were divided into 3 groups according to their caries intensity: group with very low and low caries intensity involving 31(28.44%) subjects, group with moderate caries intensity involving 30(27.52%) subjects, and group with high and very high caries intensity involving 48(44.04%) subjects. We took saliva samples from the subjects and analyzed the pH and urea concentrations, using the spectrophotometric method.

Results: The average concentration of salivary urea was highest in the subject group with very low and low caries intensity (9.13±3.8 mmol/L), followed by the group with moderate caries intensity (7.57±2.9 mmol/L) and the group with high and very high caries intensity (7.22±3.3 mmol/L). The post-hoc analysis for intergroup comparisons showed that this total significance was due to a significantly higher concentration of urea in the group with low and very low caries intensity as opposed to the group with high and very high caries intensity.

The caries intensity did not significantly affect the pH value of non-stimulated saliva.

Conclusion: The concentration of urea had significantly lower values in the subject group with high and very high caries intensity, compared to the subject group with very low and low caries intensity. During our study we recorded statistically significant differences among the study groups with different caries intensity.


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