Relationship among Salivary Carbonic Anhydrase VI Activity and Flow Rate, Biofilm pH and Caries in Primary Dentition

Abstract

This study aimed to determine the activity of carbonic anhydrase isoenzyme VI (CAVI) in the saliva of preschool children with caries and to investigate the relationship between caries and salivary CAVI activity, salivary flow rate and biofilm pH before and after a 20% sucrose rinse. Thirty preschool children aged 45.3–80.3 months were divided into two groups: a caries-free group and a caries group. Clinical examinations were conducted by one examiner (ĸ = 0.95) according to WHO criteria (dmfs) and early caries lesions. From each subject, CAVI activity, salivary flow rate and plaque pH were determined before and after a sucrose rinse. The results were submitted to Wilcoxon, Mann-Whitney and Spearman correlation tests (α = 0.05). The results showed that prerinse CAVI activity and its variation were higher in the saliva from caries children than from caries-free children. No difference was found between the two groups in postrinse salivary CAVI activity. After rinsing, biofilm pH differences were lower in both groups (p = 0.0012 and p = 0.0037 for the caries and caries-free groups, respectively). Also, after the sucrose rinse, salivary flow rate significantly increased in caries and caries-free groups (p = 0.0003, p = 0.0037). The variation of salivary CAVI activity was negatively correlated with caries (r = –0.501, p = 0.005). Child’s age showed a positive correlation with caries (r = 0.456, p = 0.011). These results suggest that variation of salivary CAVI activity and child’s age are associated with dental caries in preschool children.

Salivary carbonic anhydrase, pH and phosphate buffer concentrations as potential biomarkers of caries risk in children

“…[19,[21][22][23] On the other hand, some of our results were not in agreement with other authors. [23][24][25] This conflict may be due to the difference in method of analysis as our study were able to determine the concentration of salivary CA VI while Frasseto et al [25] used the zymography method to quantitatively determine the activity of salivary CA VI. [24] Their results indicate significantly higher activity of CA in stimulated than non-stimulated saliva in both examined groups, while Surdilović et al [20] reported a positive correlation between CA VI concentration and saliva secretion.…”

Children with a Higher Activity of Carbonic Anhydrase VI in Saliva Are More Likely to Develop Dental Caries

“…We based the sample power calculation (95%, α = 5%) on a study previously performed by our group [Frasseto et al, 2012] in which we used a similar methodology and found that the activity of CA VI in the saliva of caries and caries-free preschool children was 42.75 ± 32.47 and 19.13 ± 16.391, respectively. The sample size was based on the averages for two independent samples and a bilateral test (parametric test) with the equation: …”

“…In the same way, Szabó [1974] found a higher concentration of CA VI in saliva of 7-to 14-year-old caries-free children than in children with caries. However, the previous investigation by Frasseto et al [2012] employed the zymography method and quantitatively determined the activity of salivary CA VI. These authors demonstrated that after a cariogenic challenge the activity of salivary CA VI was higher in preschool children with dental caries.…”

Effect of Genetic Polymorphisms in <b><i>CA6</i></b> Gene on the Expression and Catalytic Activity of Human Salivary Carbonic Anhydrase VI

“…The importance of CA VI is evidenced by its involvement in several malfunctions. Low CA VI concentrations and activity in saliva were associated with the prevalence of dental caries [Kivelä et al, 1999;Frasseto et al, 2012]. Salivary bicarbonate secretion is also known to be important in the maintenance of esophageal pH homeostasis [Helm et al, 1984].…”