Annotation Fluoride Release from Sodium Fluoride and Chlorhexidine Difluoride Mouth Rinses A. A. HUSSAIN, J. H. KRAAL, and H. WAHNER Colle,e of Pharmacy and Dentistry, University of Kentucky. Lcxington, Kentucky 40506, USA J Dent Res 57(9-10):872, September-October 1978
Chlorhexidine was prepared by dissolving chlorhexidine base in an aqueous solution of ascorbic acid and subsequent addition of saturated sodium fluoride. The resulting crystalline precipitate was retrieved by filtration, washed in distilled water and dried. Adult dentulous subjects were asked to rinse their mouths with 10 ml of either 7.34 X 10-3 molar sodium fluoride or 3.66 X 10-3 molar chlorhexidine difluoride solution for one minute. The expectorate was collected, measured, and saved for analysis. Then approximately 2 to 3 ml unstimulated whole saliva samples were collected at various times-up to 4V/2 hoursafter the mouth rinse and likewise saved for analysis. All mouth rinses were done at approximately 9 a.m. and nothing was taken orally during the experimental period. Salivary fluoride concentrations were determined with a selective electrode according to manufacturers instructions (Beckman). Chlorhexidine in saliva was determined after extraction as described by JENSEN and CHRISTENSEN (I Periodontal Res 6:
306, 1971). The results of the determinations are given in the table. It appears that approximately 3/4 of the chlorhexidine and 1/5 of the fluoride given in the mouth washes were retained in the mouth. Both rinses contained an equal amount of fluoride and the amount retained was essentially similar. Our observations indicate that the salivary Received for publication March 8, 1978. Accepted for publication March 29, 1978.
fluoride concentration dropped to half the original value in about 6 minutes and that there was no difference in this respect between the sodium and chlorhexidine fluoride compounds. By contrast about 60 minutes were needed for 50% reduction in salivary chlorhexidine levels. Thus, the amount of fluoride retained in the mouth as well as the subsequent salivary fluoride concentrations were essentially the same for both kinds of rinses and definitely different from the amount of chlorhexidine retained and subsequent salivary concentrations. Apparently the nature of the cation of the fluoride salts was of minor importance in the retention of the fluoride in the mouth. Both chlorhexidine difluoride and sodium fluoride ionize in aqueous solutions to the same extent: NaF = Na+ + F Ch F2 = Ch++ + 2F dF = k [F], the rate of clearance since dt d F/dt) should be the same for solutions of equal concentrations as confirmed by our observations. It could be that the detergent effect or other phenomena caused by the organic moiety of fluoride compounds affect the dynamics of fluoride in the oral cavity to a minor extent. However, our data indicate that the use of such compounds would be futile in efforts to substantially prolong the availability of fluoride in the oral cavity. The development of controlled release systems independent of the usually rapid dissociation of fluoride compounds may be more fruitful.
TABLE CHLORHEXIDINE AND FLUORIDE IN EXPECTORATES AFTER RINSING WITH ErrHER CHLORHEXIDINE OR SODIUM FLUORIDE SOLUTIONS
From Chlorhexidine F2 Fluoride Chlorhexidine Percent recovered in expectorate immediately after each rinse 23.6 + 3.13 (11) 81.4 + Calculated maximum concentration in saliva 1.83 4 0.26 (5) 11.06 ± in meq/ml x 104 Calculated time needed for 50% reduction in salivary 6.31 ± 57.40 ± 16.28 (5) concentration in min Correlation coefficient between time and logarithm -0.81 -+- 0.11 (5) -0.97 + of concentration
From NaF
Fluoride
1.96 (11) 81.6 ± 1.63 (11) 1.44 (7)
10.59 ± 3.23 (5)
1.82 (7)
6.36 ± 1.72 (5)
0.01 (7) -0.93 + 0.04 (5)
Data are means + standard error of the mean. The number of determinations is given between parentheses. Calculated values are based on a series of observations in each of the
subjects.
872 Downloaded from jdr.sagepub.com at Australian National University on March 16, 2015 For personal use only. No other uses without permission.
Chlorhexidine was prepared by dissolving chlorhexidine base in an aqueous solution of ascorbic acid and subsequent addition of saturated sodium fluoride. The resulting crystalline precipitate was retrieved by filtration, washed in distilled water and dried. Adult dentulous subjects were asked to rinse their mouths with 10 ml of either 7.34 X 10-3 molar sodium fluoride or 3.66 X 10-3 molar chlorhexidine difluoride solution for one minute. The expectorate was collected, measured, and saved for analysis. Then approximately 2 to 3 ml unstimulated whole saliva samples were collected at various times-up to 4V/2 hoursafter the mouth rinse and likewise saved for analysis. All mouth rinses were done at approximately 9 a.m. and nothing was taken orally during the experimental period. Salivary fluoride concentrations were determined with a selective electrode according to manufacturers instructions (Beckman). Chlorhexidine in saliva was determined after extraction as described by JENSEN and CHRISTENSEN (I Periodontal Res 6:
306, 1971). The results of the determinations are given in the table. It appears that approximately 3/4 of the chlorhexidine and 1/5 of the fluoride given in the mouth washes were retained in the mouth. Both rinses contained an equal amount of fluoride and the amount retained was essentially similar. Our observations indicate that the salivary Received for publication March 8, 1978. Accepted for publication March 29, 1978.
fluoride concentration dropped to half the original value in about 6 minutes and that there was no difference in this respect between the sodium and chlorhexidine fluoride compounds. By contrast about 60 minutes were needed for 50% reduction in salivary chlorhexidine levels. Thus, the amount of fluoride retained in the mouth as well as the subsequent salivary fluoride concentrations were essentially the same for both kinds of rinses and definitely different from the amount of chlorhexidine retained and subsequent salivary concentrations. Apparently the nature of the cation of the fluoride salts was of minor importance in the retention of the fluoride in the mouth. Both chlorhexidine difluoride and sodium fluoride ionize in aqueous solutions to the same extent: NaF = Na+ + F Ch F2 = Ch++ + 2F dF = k [F], the rate of clearance since dt d F/dt) should be the same for solutions of equal concentrations as confirmed by our observations. It could be that the detergent effect or other phenomena caused by the organic moiety of fluoride compounds affect the dynamics of fluoride in the oral cavity to a minor extent. However, our data indicate that the use of such compounds would be futile in efforts to substantially prolong the availability of fluoride in the oral cavity. The development of controlled release systems independent of the usually rapid dissociation of fluoride compounds may be more fruitful.
TABLE CHLORHEXIDINE AND FLUORIDE IN EXPECTORATES AFTER RINSING WITH ErrHER CHLORHEXIDINE OR SODIUM FLUORIDE SOLUTIONS
From Chlorhexidine F2 Fluoride Chlorhexidine Percent recovered in expectorate immediately after each rinse 23.6 + 3.13 (11) 81.4 + Calculated maximum concentration in saliva 1.83 4 0.26 (5) 11.06 ± in meq/ml x 104 Calculated time needed for 50% reduction in salivary 6.31 ± 57.40 ± 16.28 (5) concentration in min Correlation coefficient between time and logarithm -0.81 -+- 0.11 (5) -0.97 + of concentration
From NaF
Fluoride
1.96 (11) 81.6 ± 1.63 (11) 1.44 (7)
10.59 ± 3.23 (5)
1.82 (7)
6.36 ± 1.72 (5)
0.01 (7) -0.93 + 0.04 (5)
Data are means + standard error of the mean. The number of determinations is given between parentheses. Calculated values are based on a series of observations in each of the
subjects.
872 Downloaded from jdr.sagepub.com at Australian National University on March 16, 2015 For personal use only. No other uses without permission.
