Gingival Fluid Flow After Gingivectomy Related to Mechanical or Chemical Plaque Control
checked for reading accuracy every day after use by quantitating known amounts of guinea-pig serum (0.1, 0.2, 0.5 µl) adsorbed on filter paper strips. 7
Experimental Procedures Eight patients, four males and four females, partici pated in this study. The mean age was 44 years, ranging from 27 to 55 years. Seven patients required gingivec tomy in all four quadrants of the mouth while one patient needed gingivectomy in the two maxillary quad rants only. Scaling and oral hygiene instructions were carried out before gingivectomy which was performed in one quadrant at a time. The periodontal packs were removed 1 week after operation. Gingival fluid measure ments and Plaque Index scoring on the corresponding tooth surfaces were performed immediately before gin givectomy, and postoperatively on days 14, 21, 28 and 35. The mean of the gingival fluid measurements in one quadrant was considered as one observation. The distri bution of the teeth involved is shown in Table 1. Both mechanical tooth cleaning and Chlorhexidine mouthrin ses were used by all patients according to a randomized "split mouth" distribution schedule (Fig. 1). For practical reasons the two quadrants of the same category were operated successively with an interval of 2 to 3 weeks. The two other quadrants treated alternatively were op erated after the termination of the follow-up of the first sequence.
by
N O P H A D O L SUPPIPAT* PER G j E R M o †
8
J A N R . JOHANSEN‡ N o HARMFUL EFFECT on gingival wound healing follow ing the use of Chlorhexidine has been described. Exper iments in dogs have shown that gingival wounds, treated topically with Chlorhexidine solution (2% or 0.2%), have less inflammatory cell infiltration than those treated with saline. In addition, it has been reported that a perio dontal pack containing 0.2% Chlorhexidine acetate, ap plied after flap operation in man, increased the healing rate clinically. Similar results have been shown when 0.2% Chlorhexidine digluconate mouthrinses, in addition to usual home care, were instituted from the day of gingivectomy. The results have been ascribed to the plaque inhibiting capacity of Chlorhexidine. The purpose of the present investigation was to com pare the effects of mechanical tooth cleaning and Chlor hexidine mouthrinses on gingival fluid flow after gingi vectomy. 1-3
4
5
Mechanical Tooth Cleaning. The patients were moti vated and instructed to use the scrub method of tooth brushing, combined with the use of a single-tufted brush (Jordan Interbrush), || an interdental brush, || or tooth picks. I Chlorhexidine Mouthrinses. A n aqueous solution of Chlorhexidine digluconate (0.2%) was used for rinsing (10 m l for 1 minute, in the morning and in the evening). The rinsing period was from the day of pack removal to the day of the last gingival fluid sampling. Statistical Method. The Wilcoxon matched-pairs signed-ranks test was used for statistical analysis.
MATERIALS A N D METHODS
Gingival Fluid Measurements The teeth were isolated with cotton rolls and dried with a gentle stream of air. HAR-601 G C F M strips§ (2.2 mm X 13 mm) were contoured slightly at the collecting ends in order to adapt closely to the teeth at the gingival margin. Each filter paper strip was placed at the orifice of a gingival crevice for 3 minutes. Immediately after removal, the strip was quantitated by the H A R - 6 0 0 Gingival Crevice Fluid Meter ( G C F M ) . § Samples were taken from the facial surfaces of maxillary anterior teeth and all mandibular teeth, but from the lingual surfaces of maxillary posterior teeth. The H A R - 6 0 0 G C F M was
9
RESULTS
6
The day-to-day readings of known volumes of serum by the H A R - 6 0 0 G C F M in the clinic showed a standard deviation of ±15%. In general, an increase in gingival fluid flow was observed from day 0 to day 14. Thereafter the flow decreased (Fig. 2). N o statistically significant differences were found between the amounts of gingival fluid sam pled from mechanically and chemically cleaned teeth after gingivectomy (Fig. 2). Plaque was found infrequently in small amounts (PI I = 1 ) during the healing period. It appeared mostly on the mechanically cleaned quadrants rather than on the
7
* Formerly a Research Associate in the Department of Periodontology, Dental Faculty, University of Oslo, Oslo, Norway. Presently in the Department of Periodontology, School of Dentistry, Chulalongkorn University, Bangkok, Thailand. † Associate Professor, Department of Periodontology, Dental Fac ulty, University of Oslo, Oslo, Norway. ‡ Professor, Department of Periodontology, Dental Faculty, Uni versity of Oslo, Oslo, Norway. § Harco Electronics Ltd., Winnipeg, Canada.
II Jordan, Oslo, Norway.
542
Volume 49 Number 10
Gingival Fluid After Gingivectomy
543
T A B L E 1. Distribution of the Teeth Used for Comparison Between the T A B L E 2. Frequencies (%)of PI I = l of the Maxillary Quadrants, Effect of Mechanical Tooth Cleaning and Chlorhexidine Mouthrinses on Cleaned Mechanically (M)or Rinsed With Chlorhexidine (CH) During Healing AfterGingivectomy Gingival Fluid Flow After Gingivectomy Mechanical tooth clean ing
Chlorhexidine mouthrinses
Ante rior
Poste rior
Total
Ante rior
Poste rior
Total
24 20
20 19
44 39
23 20
23 21
46 41
Teeth
Maxillary Mandibular
Patient no.
44
39
83
43
44
Before
Day 14
M CH M CH M CH M CH M CH M CH M CH M CH
20 0 20 25 0 50 17 0 17 17 100 0 0 17 17 0
0 0 0 0 33 0 17 0 0 0 0 0 100 0 0 0
Day 21
Day 28
Day 35
0 0 0 17 20 17 0 0 0 0 0 0 0 33 0
0 20 0 17 0 17 0 0 17 0 0
% 1. O.L. 2. A.J.
Total
Frequencies of PI I = 1
Methods of plaque control
87 3. M.A. 4. G . F . 5. W . T . 6. L . H . 7. W . A .
F I G U R E 1. A randomized "split mouth" distribution schedule. M = Mechanical tooth cleaning. C H = Chlorhexidine mouthrinses. The two quadrants of the same category were operated succes sively with an interval of 2 to 3 weeks, whereas the rest were operated after the termination of the follow-up.
8. A . W .
0 0 0 0 0 50 0 0 57 0 0 0 0 0
0 17 0
T A B L E 3. Frequencies (%) of PI I = I of the Mandibular Quandrants, Cleaned Mechanically (M) or Rinsed With Chlorhexidine (CH) During Healing After Gingivectomy
Patient no.
Frequencies of PI I = 1
Methods of plaque control
Before
Day 14
M CH M CH M CH M CH M CH M CH M CH
0 0 33 0 0 17 0 0 0 0 0 0 0 0
0 0 0 17 0 0 0 0 17 0 67 0 0 0
Day 21
Day 28
Day 35
0 0 33 0 14 0 0 0 33 0 33 17 0 0
0
% 2. A.J. 3. M.A. 4. G . F . 5. W . T . 6. L . H . 7. W.A. 8. A.W.
0 0 17 0 0 0 0 0 17 0 0 0 0 0
11, 1 2
Chlorhexidine rinsed quadrants (Tables 2 and 3). How ever the observed difference was not statistically signifi cant. DISCUSSION
The readings of the H A R - 6 0 0 G C F M are influenced by environmental conditions. Therefore, the observed method error seems acceptable in longitudinal study. 7
0 17 0 0 0 0
Previous studies have shown that the intracrevicular method of gingival fluid sampling may be used to indicate the rate of healing after gingival surgery i n man and i n the d o g . The present study showed that the orifice method may also be used for the same purpose. The decreasing gingival fluid flow was probably due to a gradual resolution of the acute inflammation after surgical trauma and subsequent regeneration of the crevicular epithelium. It was observed that 0.2% Chlorhexidine mouthrinses, twice daily, were able to keep the dentition practically plaque free during the healing period. The insignificant differences in plaque amounts between both methods of plaque control would explain the consistency i n fluid flow during the experiment. 10
F I G U R E 2. Gingival fluid flow after gingivectomy of the maxil lary and mandibular quadrants, either cleaned mechanically or rinsed with Chlorhexidine.
50 0 14 0
13-15
6
1 1 ,1 4
544
J. Periodontol. October, 1978
Suppipat, Gjermo, Johansen
The present results failed to support previous findings that Chlorhexidine increased the rate of gingival wound healing in humans. This may be due to different experimental designs. The above studies focused the effect of Chlorhexidine on healing under periodontal packs, while our study aimed at the effect after pack removal. During the Chlorhexidine period, some of the previ ously reported side effects were seen. The stained pellicle on the tooth surfaces was easily removed by a rubber cup and pumice. The discoloration of tongues disappeared shortly after the termination of the rinsing period. 4, 5
16-19
SUMMARY
The effects of mechanical tooth cleaning and 0.2% Chlorhexidine mouthrinses on healing after gingivectomy were compared in 8 patients by means of a "split mouth" technique. The experiment began after periodontal pack removal on day 7. Gingival fluid was sampled immedi ately before and on days 14, 21, 28, 35 after gingivec tomy. The results showed that mechanical and chemical plaque control were equally effective in promoting heal ing after gingivectomy as evaluated by gingival fluid measurements. ACKNOWLEDGMENTS
This study was made possible through a fellowship granted by the Norwegian Agency for International Development (NORAD). REFERENCES
1. Lindhe, J., Hamp, S.-E., Löe, H., and Rindom Schiött, C.: Influence of topical application of Chlorhexidine on chronic gingivitis and gingival wound healing in the dog. Scand J Dent Res78:471, 1970. 2. Hirst, R. C., Egelberg, J., Hornbuckle, G. C , Oliver, R. C., and Rathbun, W. E.: Microscopic evaluation of topically applied Chlorhexidine gluconate on gingival wound healing in dogs. J SC State Dent Assoc 41: 311, 1973. 3. Hamp, S.-E., Rosling, B., and Lindhe, J.: Effect of Chlor hexidine on gingival wound healing in the dog. A histometric
study. J Clin Periodont 2: 143, 1975. 4. Asboe-Jörgensen, V., Attström, R., Lang, N . P., and Löe, H.: Effect of a Chlorhexidine dressing on the healing after periodontal surgery. J Periodontol 45: 13, 1974. 5. Langebaek, J., and Bay, L.: The effect of Chlorhexidine mouthrinses on healing after gingivectomy. I ADR Abstr. No. 457, 1975. 6. Löe, H., and Holm-Pedersen, P.: Absence and presence of fluid from normal and inflamed gingivae. Periodontics 3: 171, 1965. 7. Suppipat, N . , and Suppipat, N.: Evaluation of an elec tronic device for gingival fluid quantitation. J Periodontol 48: 388, 1977. 8. Löe, H.: The Gingival Index, the Plaque Index and the Retention Index Systems. J Periodontol 38: 610, 1967. 9. Siegel, S.: Nonparametric Statistics for the Behavioral Sciences, p 75. Tokyo, McGraw-Hill Kogakusha, Ltd., 1956. 10. Brill, N.: The gingival pocket fluid. Acta Odontol Scand (suppl 32) 1962. 11. Arnold, R., Lunstad, G., Bissada, N., and Stallard, R.: Alterations in crevicular fluid flow during healing following gingival surgery. J Periodont Res 1: 303, 1966. 12. Sandalli, P., and Wade, A. B.: Alterations in crevicular fluid flow during healing following gingivectomy and flap procedures. J Periodont Res 4: 314, 1969. 13. Lindhe, J., and Hugoson, A.: The influence of estrogen and progesterone on gingival exudation of regenerating dentogingival tissue. ParOdontologie 23: 16, 1969. 14. Hugoson, A., and Lindhe, J.: Gingival tissue regenera tion in female dogs treated with sex hormones. Clinical obser vations. Odontol Revy 22: 237, 1971. 15. Hugoson, A., and Lindhe, J.: Gingival tissue regenera tion in female dogs treated with sex hormones. Histological observations. Odontol Revy 22: 425, 1971. 16. Löe, H., and Rindom Schiött, C : The effect of suppres sion of the oral microflora upon the development of dental plaque and gingivitis. W. D. McHugh (ed), Dental Plaque, p 247. Edinburgh, E. & S. Livingstone, 1970. 17. Löe, H., and Rindom Schiött, C.: The effect of mouth rinses and topical application of Chlorhexidine on the devel opment of dental plaque and gingivitis in man. J Periodont Res 5: 79, 1970. 18. Gjermo, P., Baastad, K . L., and Rolla, G.: The plaqueinhibiting capacity of 11 antibacterial compounds. J Periodont Res 5: 102, 1970. 19. Flötra, L., Gjermo, P., Rölla, G., and Waerhaug, J.: Side effects of Chlorhexidine mouthwashes. Scand J Dent Res 79: 119, 1971.
checked for reading accuracy every day after use by quantitating known amounts of guinea-pig serum (0.1, 0.2, 0.5 µl) adsorbed on filter paper strips. 7
Experimental Procedures Eight patients, four males and four females, partici pated in this study. The mean age was 44 years, ranging from 27 to 55 years. Seven patients required gingivec tomy in all four quadrants of the mouth while one patient needed gingivectomy in the two maxillary quad rants only. Scaling and oral hygiene instructions were carried out before gingivectomy which was performed in one quadrant at a time. The periodontal packs were removed 1 week after operation. Gingival fluid measure ments and Plaque Index scoring on the corresponding tooth surfaces were performed immediately before gin givectomy, and postoperatively on days 14, 21, 28 and 35. The mean of the gingival fluid measurements in one quadrant was considered as one observation. The distri bution of the teeth involved is shown in Table 1. Both mechanical tooth cleaning and Chlorhexidine mouthrin ses were used by all patients according to a randomized "split mouth" distribution schedule (Fig. 1). For practical reasons the two quadrants of the same category were operated successively with an interval of 2 to 3 weeks. The two other quadrants treated alternatively were op erated after the termination of the follow-up of the first sequence.
by
N O P H A D O L SUPPIPAT* PER G j E R M o †
8
J A N R . JOHANSEN‡ N o HARMFUL EFFECT on gingival wound healing follow ing the use of Chlorhexidine has been described. Exper iments in dogs have shown that gingival wounds, treated topically with Chlorhexidine solution (2% or 0.2%), have less inflammatory cell infiltration than those treated with saline. In addition, it has been reported that a perio dontal pack containing 0.2% Chlorhexidine acetate, ap plied after flap operation in man, increased the healing rate clinically. Similar results have been shown when 0.2% Chlorhexidine digluconate mouthrinses, in addition to usual home care, were instituted from the day of gingivectomy. The results have been ascribed to the plaque inhibiting capacity of Chlorhexidine. The purpose of the present investigation was to com pare the effects of mechanical tooth cleaning and Chlor hexidine mouthrinses on gingival fluid flow after gingi vectomy. 1-3
4
5
Mechanical Tooth Cleaning. The patients were moti vated and instructed to use the scrub method of tooth brushing, combined with the use of a single-tufted brush (Jordan Interbrush), || an interdental brush, || or tooth picks. I Chlorhexidine Mouthrinses. A n aqueous solution of Chlorhexidine digluconate (0.2%) was used for rinsing (10 m l for 1 minute, in the morning and in the evening). The rinsing period was from the day of pack removal to the day of the last gingival fluid sampling. Statistical Method. The Wilcoxon matched-pairs signed-ranks test was used for statistical analysis.
MATERIALS A N D METHODS
Gingival Fluid Measurements The teeth were isolated with cotton rolls and dried with a gentle stream of air. HAR-601 G C F M strips§ (2.2 mm X 13 mm) were contoured slightly at the collecting ends in order to adapt closely to the teeth at the gingival margin. Each filter paper strip was placed at the orifice of a gingival crevice for 3 minutes. Immediately after removal, the strip was quantitated by the H A R - 6 0 0 Gingival Crevice Fluid Meter ( G C F M ) . § Samples were taken from the facial surfaces of maxillary anterior teeth and all mandibular teeth, but from the lingual surfaces of maxillary posterior teeth. The H A R - 6 0 0 G C F M was
9
RESULTS
6
The day-to-day readings of known volumes of serum by the H A R - 6 0 0 G C F M in the clinic showed a standard deviation of ±15%. In general, an increase in gingival fluid flow was observed from day 0 to day 14. Thereafter the flow decreased (Fig. 2). N o statistically significant differences were found between the amounts of gingival fluid sam pled from mechanically and chemically cleaned teeth after gingivectomy (Fig. 2). Plaque was found infrequently in small amounts (PI I = 1 ) during the healing period. It appeared mostly on the mechanically cleaned quadrants rather than on the
7
* Formerly a Research Associate in the Department of Periodontology, Dental Faculty, University of Oslo, Oslo, Norway. Presently in the Department of Periodontology, School of Dentistry, Chulalongkorn University, Bangkok, Thailand. † Associate Professor, Department of Periodontology, Dental Fac ulty, University of Oslo, Oslo, Norway. ‡ Professor, Department of Periodontology, Dental Faculty, Uni versity of Oslo, Oslo, Norway. § Harco Electronics Ltd., Winnipeg, Canada.
II Jordan, Oslo, Norway.
542
Volume 49 Number 10
Gingival Fluid After Gingivectomy
543
T A B L E 1. Distribution of the Teeth Used for Comparison Between the T A B L E 2. Frequencies (%)of PI I = l of the Maxillary Quadrants, Effect of Mechanical Tooth Cleaning and Chlorhexidine Mouthrinses on Cleaned Mechanically (M)or Rinsed With Chlorhexidine (CH) During Healing AfterGingivectomy Gingival Fluid Flow After Gingivectomy Mechanical tooth clean ing
Chlorhexidine mouthrinses
Ante rior
Poste rior
Total
Ante rior
Poste rior
Total
24 20
20 19
44 39
23 20
23 21
46 41
Teeth
Maxillary Mandibular
Patient no.
44
39
83
43
44
Before
Day 14
M CH M CH M CH M CH M CH M CH M CH M CH
20 0 20 25 0 50 17 0 17 17 100 0 0 17 17 0
0 0 0 0 33 0 17 0 0 0 0 0 100 0 0 0
Day 21
Day 28
Day 35
0 0 0 17 20 17 0 0 0 0 0 0 0 33 0
0 20 0 17 0 17 0 0 17 0 0
% 1. O.L. 2. A.J.
Total
Frequencies of PI I = 1
Methods of plaque control
87 3. M.A. 4. G . F . 5. W . T . 6. L . H . 7. W . A .
F I G U R E 1. A randomized "split mouth" distribution schedule. M = Mechanical tooth cleaning. C H = Chlorhexidine mouthrinses. The two quadrants of the same category were operated succes sively with an interval of 2 to 3 weeks, whereas the rest were operated after the termination of the follow-up.
8. A . W .
0 0 0 0 0 50 0 0 57 0 0 0 0 0
0 17 0
T A B L E 3. Frequencies (%) of PI I = I of the Mandibular Quandrants, Cleaned Mechanically (M) or Rinsed With Chlorhexidine (CH) During Healing After Gingivectomy
Patient no.
Frequencies of PI I = 1
Methods of plaque control
Before
Day 14
M CH M CH M CH M CH M CH M CH M CH
0 0 33 0 0 17 0 0 0 0 0 0 0 0
0 0 0 17 0 0 0 0 17 0 67 0 0 0
Day 21
Day 28
Day 35
0 0 33 0 14 0 0 0 33 0 33 17 0 0
0
% 2. A.J. 3. M.A. 4. G . F . 5. W . T . 6. L . H . 7. W.A. 8. A.W.
0 0 17 0 0 0 0 0 17 0 0 0 0 0
11, 1 2
Chlorhexidine rinsed quadrants (Tables 2 and 3). How ever the observed difference was not statistically signifi cant. DISCUSSION
The readings of the H A R - 6 0 0 G C F M are influenced by environmental conditions. Therefore, the observed method error seems acceptable in longitudinal study. 7
0 17 0 0 0 0
Previous studies have shown that the intracrevicular method of gingival fluid sampling may be used to indicate the rate of healing after gingival surgery i n man and i n the d o g . The present study showed that the orifice method may also be used for the same purpose. The decreasing gingival fluid flow was probably due to a gradual resolution of the acute inflammation after surgical trauma and subsequent regeneration of the crevicular epithelium. It was observed that 0.2% Chlorhexidine mouthrinses, twice daily, were able to keep the dentition practically plaque free during the healing period. The insignificant differences in plaque amounts between both methods of plaque control would explain the consistency i n fluid flow during the experiment. 10
F I G U R E 2. Gingival fluid flow after gingivectomy of the maxil lary and mandibular quadrants, either cleaned mechanically or rinsed with Chlorhexidine.
50 0 14 0
13-15
6
1 1 ,1 4
544
J. Periodontol. October, 1978
Suppipat, Gjermo, Johansen
The present results failed to support previous findings that Chlorhexidine increased the rate of gingival wound healing in humans. This may be due to different experimental designs. The above studies focused the effect of Chlorhexidine on healing under periodontal packs, while our study aimed at the effect after pack removal. During the Chlorhexidine period, some of the previ ously reported side effects were seen. The stained pellicle on the tooth surfaces was easily removed by a rubber cup and pumice. The discoloration of tongues disappeared shortly after the termination of the rinsing period. 4, 5
16-19
SUMMARY
The effects of mechanical tooth cleaning and 0.2% Chlorhexidine mouthrinses on healing after gingivectomy were compared in 8 patients by means of a "split mouth" technique. The experiment began after periodontal pack removal on day 7. Gingival fluid was sampled immedi ately before and on days 14, 21, 28, 35 after gingivec tomy. The results showed that mechanical and chemical plaque control were equally effective in promoting heal ing after gingivectomy as evaluated by gingival fluid measurements. ACKNOWLEDGMENTS
This study was made possible through a fellowship granted by the Norwegian Agency for International Development (NORAD). REFERENCES
1. Lindhe, J., Hamp, S.-E., Löe, H., and Rindom Schiött, C.: Influence of topical application of Chlorhexidine on chronic gingivitis and gingival wound healing in the dog. Scand J Dent Res78:471, 1970. 2. Hirst, R. C., Egelberg, J., Hornbuckle, G. C , Oliver, R. C., and Rathbun, W. E.: Microscopic evaluation of topically applied Chlorhexidine gluconate on gingival wound healing in dogs. J SC State Dent Assoc 41: 311, 1973. 3. Hamp, S.-E., Rosling, B., and Lindhe, J.: Effect of Chlor hexidine on gingival wound healing in the dog. A histometric
study. J Clin Periodont 2: 143, 1975. 4. Asboe-Jörgensen, V., Attström, R., Lang, N . P., and Löe, H.: Effect of a Chlorhexidine dressing on the healing after periodontal surgery. J Periodontol 45: 13, 1974. 5. Langebaek, J., and Bay, L.: The effect of Chlorhexidine mouthrinses on healing after gingivectomy. I ADR Abstr. No. 457, 1975. 6. Löe, H., and Holm-Pedersen, P.: Absence and presence of fluid from normal and inflamed gingivae. Periodontics 3: 171, 1965. 7. Suppipat, N . , and Suppipat, N.: Evaluation of an elec tronic device for gingival fluid quantitation. J Periodontol 48: 388, 1977. 8. Löe, H.: The Gingival Index, the Plaque Index and the Retention Index Systems. J Periodontol 38: 610, 1967. 9. Siegel, S.: Nonparametric Statistics for the Behavioral Sciences, p 75. Tokyo, McGraw-Hill Kogakusha, Ltd., 1956. 10. Brill, N.: The gingival pocket fluid. Acta Odontol Scand (suppl 32) 1962. 11. Arnold, R., Lunstad, G., Bissada, N., and Stallard, R.: Alterations in crevicular fluid flow during healing following gingival surgery. J Periodont Res 1: 303, 1966. 12. Sandalli, P., and Wade, A. B.: Alterations in crevicular fluid flow during healing following gingivectomy and flap procedures. J Periodont Res 4: 314, 1969. 13. Lindhe, J., and Hugoson, A.: The influence of estrogen and progesterone on gingival exudation of regenerating dentogingival tissue. ParOdontologie 23: 16, 1969. 14. Hugoson, A., and Lindhe, J.: Gingival tissue regenera tion in female dogs treated with sex hormones. Clinical obser vations. Odontol Revy 22: 237, 1971. 15. Hugoson, A., and Lindhe, J.: Gingival tissue regenera tion in female dogs treated with sex hormones. Histological observations. Odontol Revy 22: 425, 1971. 16. Löe, H., and Rindom Schiött, C : The effect of suppres sion of the oral microflora upon the development of dental plaque and gingivitis. W. D. McHugh (ed), Dental Plaque, p 247. Edinburgh, E. & S. Livingstone, 1970. 17. Löe, H., and Rindom Schiött, C.: The effect of mouth rinses and topical application of Chlorhexidine on the devel opment of dental plaque and gingivitis in man. J Periodont Res 5: 79, 1970. 18. Gjermo, P., Baastad, K . L., and Rolla, G.: The plaqueinhibiting capacity of 11 antibacterial compounds. J Periodont Res 5: 102, 1970. 19. Flötra, L., Gjermo, P., Rölla, G., and Waerhaug, J.: Side effects of Chlorhexidine mouthwashes. Scand J Dent Res 79: 119, 1971.
