Pulpal and root sensitivity rated to periodontal therapy James A. Wallace, DDS, MDS, MSD, MS,a and Nabil F. Bissada, DDS, A4SD,b Cleveland, Ohio SCHOOL
OF DENTISTRY,
CASE
WESTERN
RESERVE
UNIVERSITY
The purpose of this clinical investigation was to determine if periodontal treatment consisting of scaling, root planing, and periodontal surgery produced any change in pulpal or root sensitivity. Ten patients were tested, with a total of 84 observations. There were 42 periodontally treated teeth, with 42 contralateral teeth serving as control specimens. The teeth were evaluated with stimuli from an electric pulp tester, cold, and air. The electric pulp tester was found to be reliable in assessing the pulpal sensitivity. Neither the amount of periodontal destruction nor the extent of periodontal treatment had any effect on the pulp. Scaling and root planing had no significant effect on root sensitivity. Periodontal surgery was directly related to root sensitivity in terms of the extent of root surface exposure. An association was observed clinically between plaque accumulation after periodontal surgery and root sensitivity. (ORAL SURC ORAL MED ORAL PATHOL 1990;69:743-7)
N
erve fibers entering the teeth have been identified histologically as myelinated A-delta fibers and unmyelinated C fibers, with the A-delta having a lower exitable threshold than the C fibers.] Tooth pulp nerves, however, represent pure afferent pain fiber.2 The pain receptors of the pulp are free nerve endings that in essence are unmyelinated dendrites that overlap without fusing. 3-5The major portion of nerve terminations occur in the coronal sections, especially the pulp horns, with less than 10% terminating in the root.6 Brannstrom7 and Lilja* have postulated a hydrodynamic mechanism for pain perception in the dentin. Exposed open dentinal tubules, therefore, result in increased fluid flow and increased dentin sensitivity.“, 9 Patients undergoing periodontal treatment are particularly susceptible to dentin hypersensitivity, which frequently exists before periodontal treatment and may be aggravated by surgical intervention. Uchida and coworkers10 examined 60 adult patients for dentin hypersensitivity before periodontal surgery. The presurgical examination revealed 249 hypersensitive areas. After surgery, there was more than a 100% increase in dentin hypersensitivity. “Director, bProfessor 7/15/12441
Graduate Endodontics Program. and Chairman, Department of Periodontics.
After periodontal therapy, reduction of the gingival protective barrier may result from curettage or excision of tissue that exposes the root surfaces, while root planing may remove 20 to 50 pm of cementum and expose the dentinal tubules to external stimuli.’ 1 The purpose of this investigation was, therefore, to determine if scaling, root planing, and periodontal surgery can produce significant change in pulpal or root sensitivity or both. MATERIAL
AND METHODS
The methods used to establish the relationship between root sensitivity and periodontal treatment were an air stimulus, a cold stimulus, and an electric stimulus. The air stimulus was a blast of air, lasting for up to 3 seconds, from the dental unit air syringe; the air remained at a constant temperature of 70” F r 3” and a pressure of 60 pounds per square inch. Air was directed at the cemento-enamel junction, the adjacent exposed root surface, or both. The tooth tested was thoroughly dried with gauze squares and isolated with cotton rolls so as not to elicit a response from an adjacent tooth. This method is recommended by a panel of dental experts appointed by the Food and Drug Administration.t2 The cold test was administered with a cotton-tipped applicator saturated with FRIGTDENT (Ellman In743
ORAL SURC ORAL
744
Wallace and Bissada
Table
I. Means and standard deviations for experimental Before
ELECTRIC TESTS Experimental Control time period related to experimental treatment COLD TESTS Experimental Control time period related to experimental treatment AIR TESTS Experimental Control time period related to experimental treatment *Statistically
scaling
= -0.434
*Not
= -0.15 statistically
-
Before
surgery
After
surgery
18.37 t 6.92 20.59 + 5.81
1.91 +- 0.79 2.01 k 0.98
2.11 t 0.88 2.05 k 0.87
2.1 k 0.85 2.05 + 0.85
2.08 k 0.71 2.00 k 0.84
1.09 t 0.86 0.71 r 0.61
0.79 k 0.87 0.69 * 0.64
0.81 + 0.82* 0.71 + 0.62*
1.39 2 0.89* 0.67 k 0.64*
After scaling
r = -0.445
Before surgery r =
-0.418
After surgery r = -0.226
significant.
Ill. Correlation coefficients (r) for response to electric stimulus versus response to air stimulus*
r
scaling
20.49 i 6.55 22.23 ic 7.48
Table
Before scaling
After
significant.
Before scaling
statistically
and control groups
20.76 rt 6.70 23.19 i 7.95
11.Correlation coefficients (rj for response to electric stimulus versus response to cold stimulus*
*Not
ORAL PATHOL June 1990
21.49 t 6.29 22.31 k 5.13
Table
r
MED
After scaling
Before surgery
After surgery
r = -0.07
r = -0.022
r = -0.48
significant.
ternational Manufacturing Inc., Hewlett, N.Y.) that produced a temperature of 14” F. It was applied facially on the anterior teeth and occlusally on posterior teeth up to a maximum of 3 seconds. The air and the cold tests were recorded on a scale of 0 to 3: 0, no response; 1, mild perceptible response; 2, moderate response-patient perceived pain but demonstrated no physical response such as wincing, frowning, squirming, or moving quickly; 3, severe response-patient reported pain, physically reacted as indicated above, or both. The probe of the Analytic Technology Vitality Scanner (Analytic Technology, Redmond, Wash.) was placed on the tooth with voltage increased from zero to a level at which the patient felt a sensation, usually described as warmth or tingling.13 This point has been described as a prepain or a nonpain sensation.‘4 This voltage point is taken as the quantitative level of sensitivity. The tested tooth was dried with gauze squares and isolated with cotton rolls. An electrolyte toothpaste was used to assure a closed testing circuit. The generously coated electrode was
placed on sound-dried enamel on the middle third of the facial surface. Any teeth with obvious cracks or large restorations that would interfere with the test were not used. Two readings were taken and an average used. Ten subjects were tested, with a total of 84 observations. There were nine women and one man, ranging in age from 33 to 66 years. There were 42 experimental and 42 control observations. An anterior premolar and molar were used when possible in each test quadrant, where they were evaluated before scaling, after scaling, before surgery, and after surgery. The corresponding teeth in the contralateral quadrant served as control specimens and were tested in the same manner. The subjects’ experimental and control quadrants were randomly assigned. The treatment and tests were administered by one investigator who is an endodontist. The periodontal treatment consisted of scaling and root planing of the involved teeth followed by the appropriate periodontal surgery consisting of modified Widman flap, osseous contouring, decalcified freezedried bone grafting, or apically positioned full thickness flaps. The results were evaluated by means of the analysis of variance and factorial design, 2R (experimental and control; R = repeated measure) by 4R (test periods) with the program BMDP-2V (University of California Press, Berkeley, Calif.) and the SchifI’s test (Table I). A correlation coefficient was determined between the electric stimulus compared to the cold stimulus and the electric stimulus compared to the air stimulus (Tables II and III). RESULTS
Analysis of variance showed no statistically significant differences between the control and experimental teeth when electric stimulus is used @ > 0.05).
Volume 69 Number 6
Tooth sensitivity 0 Pre-scalir!4
n Pm-surgery
El Pre-scaling
n Pm-surgery
q
q
@d Post-scaling
q
Post-scaling
Post-swQerY
g 40 t y
therapy
745
Post-swge4y
Q 40
20 0
,
2
3
4
5
6
7
8
9
10
F0 $0
20
9
2
s
1 0
3 9
and periodontal
81 0 1
2
3
4
5
6
7
8
9
10
3
2
a
1 0
2
3
4
5
6
7
8
9
10
1
2
3
4
5
6
7
8
9
10
3
2
K
1
2 a 4
,
2
3
4
5
6
7
8
9
1 0
10
SUBJECTS
Fig. 1. Responsesto electric, cold, and air stimuli by the
SUBJECTS
Fig. 2. Responses to the electric, cold, and air stimuli by control group at the four treatment time intervals.
experimental group at the time of four treatments. The overall treatment mean was 20.28, and the overall control mean 22.08. Analysis of variance also showed no statistically significant differences among the four treatments (p > 0.05) when the electric stimulus test is applied. No statistically significant interaction between treated teeth and control teeth was found with the analysis of variance and the electric stimulus, with F=0.15atp=0.92. The analysis of variance of the cold stimulus revealed no statistically significant differences between control teeth and treated teeth with F = O.OC and P = 0.95. The overall treatment mean was 2.05, and the overall control mean 2.02. The analysis of variance and the cold tests irrespective of treatment showed no statistically significant differences with F = 0.53 and P = 0.67. No statistically significant interaction between treated teeth and control teeth was found with the analysis of variance and the cold stimulus with F = 0.31 and P = 0.82. The analysis of variance the air test revealed no statistically significant differences between treated and control teeth with F = i.07 and P = 0.31. The overall treatment mean was 1.02, and the overall control mean, 0.70. The analysis of variance and the air test irrespec. tive of treatment demonstrate a statistically significant difference with F = 3.59 and P = 0.02. A statistically significant interaction between treated and control teeth was found with the analysis of variance aid the air tests with F = 4.33 and P = 0.08. The overall mean for the treatment group was 1.02, and the overall mean for the control group was 0.70. The Schiffs test at P = 0.01 revealed no statistically significant difference between the responses be-
fore scaling and after scaling, but there was a statistically significant difference between the responses before and after surgery for the treatment groups and between these treatment groups and control teeth. The previous data were represented in Table I. Correlation coefficients were calculated for response to electric stimuli versus response to cold stimuli; the difference was found not to be statistically significant. Correlation coefficients were calculated for response to electric stimuli compared to response to air stimuli; the difference was found not to be statistically significant. Although there is a trend toward a negative correlation, this trend was not significant (Tables II and III). Patients 4,6,8, and 10 demonstrated a trend of increased sensitivity to the air stimulus, and this sensitivity was noted clinically. They presented more plaque and calculus than the remaining patients did (Fig. 1, experimental, versus Fig. 2, control). There was no relationship between the electric stimulus, cold stimulus, or air stimulus and the type of periodontitis the patient exhibited (case types II, III, or IV). Clinically, patients with the apically positioned flap surgery and osseous contouring were more sensitive to the air stimulus than were patients with the modified Widman flap treatment (Fig. 1, experimental, versus Fig. 2, control). DISCUSSION
The present study did not show significant differences in the electric tests between treatment and control groups or within the treatment groups, or interaction between treatment and control groups. Since the electric tester reflects pulpal rather than dentinal sensitivity, it is assumed that the pulp was not affected by periodontal treatment, and at no time was the pul-
746
ORAL SURG ORAL MED ORAL PATHOL June 1990
Wallace and Bissada
pal threshold potential altered. Seltzer and colleagues15 state that threshold and pain tolerance of the pulp evaluated with the electric pulp tester are very close and therefore measurement of pulpal threshold versus pain tolerance, as with the cold and air stimuli, is permissible. Because the electric pulp tester measures pulpal threshold, there should be an inverse correlation to the cold and air stimuli readings. In the present study, however, the correlation coefficient analysis showed no statistically significant differences, but a trend in negative correlation (inverse relationship) was noted. Pulpal threshold as determined with the electric pulp tester was not altered by the degree of periodontal destruction. This finding is in agreement with Mazur and Massler, I6 who found that pulpal disease was not related to the degree of periodontal destruction, and with Bergenholtz and Lindhe,” who showed that, in the monkey, periodontal destruction limited to the cervical half of the root and plaque accumulation on exposed root dentin did not cause severe alteration in the pulp of the roots involved. Pulpal or root sensitivity was not related to the degree of periodontal destruction but to the degree of root surface exposure. The lack of statistically significant difference between the treatment and control groups and within the treatment groups, and of any interaction between the treatment and control groups with the cold tests demonstrates that neither the periodontal treatment nor time produced any pulpal changes. The statistically significant differences between the preperiodontal and postperiodontal treatment groups and control groups and within the periodontal treatment groups with the air stimulus illustrate an increased root sensitivity with periodontal treatments. The air stimulus measures root sensitivity and not pulpal sensitivity. Thus root sensitivity is very much related to th3 degree of root surface exposure. It is observed in this clinical study that the subjects with less than adequate plaque control tested more sensitive to the air stimuli than did the other subjects with better oral hygiene. Plaque did not alter the pulpal threshold (i.e., had no effect on the pulp) but did seem to have an effect on root sensitivity. SUMMARY
AND CONCLUSIONS
The purpose of this clinical investigation was to determine if periodontal treatment consisting of scaling, root planing: and periodontal surgery produced any change in pulpal or root sensitivity. Ten patients were tested, with a total of 84 obser-
vations. There were 42 periodontally treated teeth with 42 contralateral teeth serving as control specimens. The teeth were evaluated with the electric pulp tester, cold, and air stimuli. The following conclusions may be drawn: 1. The electric pulp tester was reliable in testing the pulpal threshold, as there was very little intersubject variation in treatment or control groups and no statistically significant differences between treatment and control groups. 2. There was no correlation between pulpal threshold and pain tolerance with periodontal treatment. 3. There was no relationship between pulpal threshold and the degree of periodontal destruction. 4. Scaling and root planing did not produce root sensitivity. 5. Periodontal surgery where increased root surface area was exposed did produce root sensitivity. 6. It was clinically observed that plaque was related to increased root sensitivity associated with periodontal surgery. REFERENCES
1. Trowbridge HO. Intradental sensory units: physiological and clinical considerations. J Endodontics 1985;11:489-98. 2. Van Hassel HJ. Cortical potentials evoked by tooth pulp stimulation in primates [PhD thesis]. Seattle, Wash. University of Washington, 1969. 3. Sweet WH. Pain. In: Field J, Mayoun HW, Hall VE, eds. Handbook of physiology. Washington, DC: American Physiology Society, 1959:459-509. 4. Bishop GH. The relationship between fiber size and sensory modality: phylogenetic implications of the afferent innervation of the cortex. J Nervous Mental Dis 1959;128:89-114. 5. Graf W, Bjorlin G. Diameters of nerve fibers in human tooth pulp. J Am Dent Assoc 1951;43:186-93. 6. Byers MR, Matthews B. Autoradiographic demonstration of ipsilateral and contralateral sensory nerve endings in cat dentin, pulp, and periodontium. Anat Ret 1981;201:24960. 7. Brannstrom M. Sensitivity of dentine. ORAL SURG ORAL MED ORAL
PATHOL
1966;21:511-26.
8. Lilja J. Innervation of the dentin [Thesis]. Goteborg, Sweden: University of Goteborg, 1980. 9. Brannstrom M, Johnson G, Nordenvall KJ. Transmission control of dentinal pain: resin impregnation of the densitization of dentin. J Am Dent Assoc 1979;99:612-8. 10. Uchida A, Yiochi W, Osamu F, Takao M, Yokio I, Hiroshi 0. Controlled clinical evaluation of a 10% strontium chloride dentifrice in treatment of dentin hypersensitivity following periodontal surgery. J Periodontol 1980;51:578-81. 11. Nishida M, Katamsi D, Ucheda A, et al. Hypersensitivity of the exposed root surface after surgical periodontal treatment. J Osaka Univ Dent Sot 1976;16:73-7. 12. Federal Register 1982;47(101,Book 2):2271 l-930. 13. Stark M, Kempler D, Pelzner RB, Rosenfield J, Leung RL, Mintatos S. Rationalization of electric pulp-testing methods. ORAL
SURC ORAL
MED ORAL
PATHOL
1977;43:598-606.
14. McGrath P, Gracely R, Dubner R, Heft M. Nonpain and pain sensations evoked by tooth pulp stimulation. Pain 1983; 15:37788. 15. Seltzer S, Stock R, Marcus R, Jackson E. Alteration of human
Volume Number
69 6
pain thresholds by nutritional manipulation and L-tryptophane supplementation. Pain 1982;13:385-93. 16. Mazur B, Massler M. Influence of periodontal disease on the dental pulp. ORAL SURG ORAL MED ORAL PATHOL 1964; 17:592-603. 17. Bergenholtz G, Lindhe J. Effect of experimental induced marginal periodontitis and periodontal scaling on the dental pulp. J Clin Periodontol 1978;5:59-73.
Tooth sensitivity Reprint requests to: Dr. James A. Wallace Graduate Endodontics School of Dentistry Case Western Reserve 2123 Abington Rd. Cleveland, OH 44106
and periodontal
Program University
therapy
747
OF DENTISTRY,
CASE
WESTERN
RESERVE
UNIVERSITY
The purpose of this clinical investigation was to determine if periodontal treatment consisting of scaling, root planing, and periodontal surgery produced any change in pulpal or root sensitivity. Ten patients were tested, with a total of 84 observations. There were 42 periodontally treated teeth, with 42 contralateral teeth serving as control specimens. The teeth were evaluated with stimuli from an electric pulp tester, cold, and air. The electric pulp tester was found to be reliable in assessing the pulpal sensitivity. Neither the amount of periodontal destruction nor the extent of periodontal treatment had any effect on the pulp. Scaling and root planing had no significant effect on root sensitivity. Periodontal surgery was directly related to root sensitivity in terms of the extent of root surface exposure. An association was observed clinically between plaque accumulation after periodontal surgery and root sensitivity. (ORAL SURC ORAL MED ORAL PATHOL 1990;69:743-7)
N
erve fibers entering the teeth have been identified histologically as myelinated A-delta fibers and unmyelinated C fibers, with the A-delta having a lower exitable threshold than the C fibers.] Tooth pulp nerves, however, represent pure afferent pain fiber.2 The pain receptors of the pulp are free nerve endings that in essence are unmyelinated dendrites that overlap without fusing. 3-5The major portion of nerve terminations occur in the coronal sections, especially the pulp horns, with less than 10% terminating in the root.6 Brannstrom7 and Lilja* have postulated a hydrodynamic mechanism for pain perception in the dentin. Exposed open dentinal tubules, therefore, result in increased fluid flow and increased dentin sensitivity.“, 9 Patients undergoing periodontal treatment are particularly susceptible to dentin hypersensitivity, which frequently exists before periodontal treatment and may be aggravated by surgical intervention. Uchida and coworkers10 examined 60 adult patients for dentin hypersensitivity before periodontal surgery. The presurgical examination revealed 249 hypersensitive areas. After surgery, there was more than a 100% increase in dentin hypersensitivity. “Director, bProfessor 7/15/12441
Graduate Endodontics Program. and Chairman, Department of Periodontics.
After periodontal therapy, reduction of the gingival protective barrier may result from curettage or excision of tissue that exposes the root surfaces, while root planing may remove 20 to 50 pm of cementum and expose the dentinal tubules to external stimuli.’ 1 The purpose of this investigation was, therefore, to determine if scaling, root planing, and periodontal surgery can produce significant change in pulpal or root sensitivity or both. MATERIAL
AND METHODS
The methods used to establish the relationship between root sensitivity and periodontal treatment were an air stimulus, a cold stimulus, and an electric stimulus. The air stimulus was a blast of air, lasting for up to 3 seconds, from the dental unit air syringe; the air remained at a constant temperature of 70” F r 3” and a pressure of 60 pounds per square inch. Air was directed at the cemento-enamel junction, the adjacent exposed root surface, or both. The tooth tested was thoroughly dried with gauze squares and isolated with cotton rolls so as not to elicit a response from an adjacent tooth. This method is recommended by a panel of dental experts appointed by the Food and Drug Administration.t2 The cold test was administered with a cotton-tipped applicator saturated with FRIGTDENT (Ellman In743
ORAL SURC ORAL
744
Wallace and Bissada
Table
I. Means and standard deviations for experimental Before
ELECTRIC TESTS Experimental Control time period related to experimental treatment COLD TESTS Experimental Control time period related to experimental treatment AIR TESTS Experimental Control time period related to experimental treatment *Statistically
scaling
= -0.434
*Not
= -0.15 statistically
-
Before
surgery
After
surgery
18.37 t 6.92 20.59 + 5.81
1.91 +- 0.79 2.01 k 0.98
2.11 t 0.88 2.05 k 0.87
2.1 k 0.85 2.05 + 0.85
2.08 k 0.71 2.00 k 0.84
1.09 t 0.86 0.71 r 0.61
0.79 k 0.87 0.69 * 0.64
0.81 + 0.82* 0.71 + 0.62*
1.39 2 0.89* 0.67 k 0.64*
After scaling
r = -0.445
Before surgery r =
-0.418
After surgery r = -0.226
significant.
Ill. Correlation coefficients (r) for response to electric stimulus versus response to air stimulus*
r
scaling
20.49 i 6.55 22.23 ic 7.48
Table
Before scaling
After
significant.
Before scaling
statistically
and control groups
20.76 rt 6.70 23.19 i 7.95
11.Correlation coefficients (rj for response to electric stimulus versus response to cold stimulus*
*Not
ORAL PATHOL June 1990
21.49 t 6.29 22.31 k 5.13
Table
r
MED
After scaling
Before surgery
After surgery
r = -0.07
r = -0.022
r = -0.48
significant.
ternational Manufacturing Inc., Hewlett, N.Y.) that produced a temperature of 14” F. It was applied facially on the anterior teeth and occlusally on posterior teeth up to a maximum of 3 seconds. The air and the cold tests were recorded on a scale of 0 to 3: 0, no response; 1, mild perceptible response; 2, moderate response-patient perceived pain but demonstrated no physical response such as wincing, frowning, squirming, or moving quickly; 3, severe response-patient reported pain, physically reacted as indicated above, or both. The probe of the Analytic Technology Vitality Scanner (Analytic Technology, Redmond, Wash.) was placed on the tooth with voltage increased from zero to a level at which the patient felt a sensation, usually described as warmth or tingling.13 This point has been described as a prepain or a nonpain sensation.‘4 This voltage point is taken as the quantitative level of sensitivity. The tested tooth was dried with gauze squares and isolated with cotton rolls. An electrolyte toothpaste was used to assure a closed testing circuit. The generously coated electrode was
placed on sound-dried enamel on the middle third of the facial surface. Any teeth with obvious cracks or large restorations that would interfere with the test were not used. Two readings were taken and an average used. Ten subjects were tested, with a total of 84 observations. There were nine women and one man, ranging in age from 33 to 66 years. There were 42 experimental and 42 control observations. An anterior premolar and molar were used when possible in each test quadrant, where they were evaluated before scaling, after scaling, before surgery, and after surgery. The corresponding teeth in the contralateral quadrant served as control specimens and were tested in the same manner. The subjects’ experimental and control quadrants were randomly assigned. The treatment and tests were administered by one investigator who is an endodontist. The periodontal treatment consisted of scaling and root planing of the involved teeth followed by the appropriate periodontal surgery consisting of modified Widman flap, osseous contouring, decalcified freezedried bone grafting, or apically positioned full thickness flaps. The results were evaluated by means of the analysis of variance and factorial design, 2R (experimental and control; R = repeated measure) by 4R (test periods) with the program BMDP-2V (University of California Press, Berkeley, Calif.) and the SchifI’s test (Table I). A correlation coefficient was determined between the electric stimulus compared to the cold stimulus and the electric stimulus compared to the air stimulus (Tables II and III). RESULTS
Analysis of variance showed no statistically significant differences between the control and experimental teeth when electric stimulus is used @ > 0.05).
Volume 69 Number 6
Tooth sensitivity 0 Pre-scalir!4
n Pm-surgery
El Pre-scaling
n Pm-surgery
q
q
@d Post-scaling
q
Post-scaling
Post-swQerY
g 40 t y
therapy
745
Post-swge4y
Q 40
20 0
,
2
3
4
5
6
7
8
9
10
F0 $0
20
9
2
s
1 0
3 9
and periodontal
81 0 1
2
3
4
5
6
7
8
9
10
3
2
a
1 0
2
3
4
5
6
7
8
9
10
1
2
3
4
5
6
7
8
9
10
3
2
K
1
2 a 4
,
2
3
4
5
6
7
8
9
1 0
10
SUBJECTS
Fig. 1. Responsesto electric, cold, and air stimuli by the
SUBJECTS
Fig. 2. Responses to the electric, cold, and air stimuli by control group at the four treatment time intervals.
experimental group at the time of four treatments. The overall treatment mean was 20.28, and the overall control mean 22.08. Analysis of variance also showed no statistically significant differences among the four treatments (p > 0.05) when the electric stimulus test is applied. No statistically significant interaction between treated teeth and control teeth was found with the analysis of variance and the electric stimulus, with F=0.15atp=0.92. The analysis of variance of the cold stimulus revealed no statistically significant differences between control teeth and treated teeth with F = O.OC and P = 0.95. The overall treatment mean was 2.05, and the overall control mean 2.02. The analysis of variance and the cold tests irrespective of treatment showed no statistically significant differences with F = 0.53 and P = 0.67. No statistically significant interaction between treated teeth and control teeth was found with the analysis of variance and the cold stimulus with F = 0.31 and P = 0.82. The analysis of variance the air test revealed no statistically significant differences between treated and control teeth with F = i.07 and P = 0.31. The overall treatment mean was 1.02, and the overall control mean, 0.70. The analysis of variance and the air test irrespec. tive of treatment demonstrate a statistically significant difference with F = 3.59 and P = 0.02. A statistically significant interaction between treated and control teeth was found with the analysis of variance aid the air tests with F = 4.33 and P = 0.08. The overall mean for the treatment group was 1.02, and the overall mean for the control group was 0.70. The Schiffs test at P = 0.01 revealed no statistically significant difference between the responses be-
fore scaling and after scaling, but there was a statistically significant difference between the responses before and after surgery for the treatment groups and between these treatment groups and control teeth. The previous data were represented in Table I. Correlation coefficients were calculated for response to electric stimuli versus response to cold stimuli; the difference was found not to be statistically significant. Correlation coefficients were calculated for response to electric stimuli compared to response to air stimuli; the difference was found not to be statistically significant. Although there is a trend toward a negative correlation, this trend was not significant (Tables II and III). Patients 4,6,8, and 10 demonstrated a trend of increased sensitivity to the air stimulus, and this sensitivity was noted clinically. They presented more plaque and calculus than the remaining patients did (Fig. 1, experimental, versus Fig. 2, control). There was no relationship between the electric stimulus, cold stimulus, or air stimulus and the type of periodontitis the patient exhibited (case types II, III, or IV). Clinically, patients with the apically positioned flap surgery and osseous contouring were more sensitive to the air stimulus than were patients with the modified Widman flap treatment (Fig. 1, experimental, versus Fig. 2, control). DISCUSSION
The present study did not show significant differences in the electric tests between treatment and control groups or within the treatment groups, or interaction between treatment and control groups. Since the electric tester reflects pulpal rather than dentinal sensitivity, it is assumed that the pulp was not affected by periodontal treatment, and at no time was the pul-
746
ORAL SURG ORAL MED ORAL PATHOL June 1990
Wallace and Bissada
pal threshold potential altered. Seltzer and colleagues15 state that threshold and pain tolerance of the pulp evaluated with the electric pulp tester are very close and therefore measurement of pulpal threshold versus pain tolerance, as with the cold and air stimuli, is permissible. Because the electric pulp tester measures pulpal threshold, there should be an inverse correlation to the cold and air stimuli readings. In the present study, however, the correlation coefficient analysis showed no statistically significant differences, but a trend in negative correlation (inverse relationship) was noted. Pulpal threshold as determined with the electric pulp tester was not altered by the degree of periodontal destruction. This finding is in agreement with Mazur and Massler, I6 who found that pulpal disease was not related to the degree of periodontal destruction, and with Bergenholtz and Lindhe,” who showed that, in the monkey, periodontal destruction limited to the cervical half of the root and plaque accumulation on exposed root dentin did not cause severe alteration in the pulp of the roots involved. Pulpal or root sensitivity was not related to the degree of periodontal destruction but to the degree of root surface exposure. The lack of statistically significant difference between the treatment and control groups and within the treatment groups, and of any interaction between the treatment and control groups with the cold tests demonstrates that neither the periodontal treatment nor time produced any pulpal changes. The statistically significant differences between the preperiodontal and postperiodontal treatment groups and control groups and within the periodontal treatment groups with the air stimulus illustrate an increased root sensitivity with periodontal treatments. The air stimulus measures root sensitivity and not pulpal sensitivity. Thus root sensitivity is very much related to th3 degree of root surface exposure. It is observed in this clinical study that the subjects with less than adequate plaque control tested more sensitive to the air stimuli than did the other subjects with better oral hygiene. Plaque did not alter the pulpal threshold (i.e., had no effect on the pulp) but did seem to have an effect on root sensitivity. SUMMARY
AND CONCLUSIONS
The purpose of this clinical investigation was to determine if periodontal treatment consisting of scaling, root planing: and periodontal surgery produced any change in pulpal or root sensitivity. Ten patients were tested, with a total of 84 obser-
vations. There were 42 periodontally treated teeth with 42 contralateral teeth serving as control specimens. The teeth were evaluated with the electric pulp tester, cold, and air stimuli. The following conclusions may be drawn: 1. The electric pulp tester was reliable in testing the pulpal threshold, as there was very little intersubject variation in treatment or control groups and no statistically significant differences between treatment and control groups. 2. There was no correlation between pulpal threshold and pain tolerance with periodontal treatment. 3. There was no relationship between pulpal threshold and the degree of periodontal destruction. 4. Scaling and root planing did not produce root sensitivity. 5. Periodontal surgery where increased root surface area was exposed did produce root sensitivity. 6. It was clinically observed that plaque was related to increased root sensitivity associated with periodontal surgery. REFERENCES
1. Trowbridge HO. Intradental sensory units: physiological and clinical considerations. J Endodontics 1985;11:489-98. 2. Van Hassel HJ. Cortical potentials evoked by tooth pulp stimulation in primates [PhD thesis]. Seattle, Wash. University of Washington, 1969. 3. Sweet WH. Pain. In: Field J, Mayoun HW, Hall VE, eds. Handbook of physiology. Washington, DC: American Physiology Society, 1959:459-509. 4. Bishop GH. The relationship between fiber size and sensory modality: phylogenetic implications of the afferent innervation of the cortex. J Nervous Mental Dis 1959;128:89-114. 5. Graf W, Bjorlin G. Diameters of nerve fibers in human tooth pulp. J Am Dent Assoc 1951;43:186-93. 6. Byers MR, Matthews B. Autoradiographic demonstration of ipsilateral and contralateral sensory nerve endings in cat dentin, pulp, and periodontium. Anat Ret 1981;201:24960. 7. Brannstrom M. Sensitivity of dentine. ORAL SURG ORAL MED ORAL
PATHOL
1966;21:511-26.
8. Lilja J. Innervation of the dentin [Thesis]. Goteborg, Sweden: University of Goteborg, 1980. 9. Brannstrom M, Johnson G, Nordenvall KJ. Transmission control of dentinal pain: resin impregnation of the densitization of dentin. J Am Dent Assoc 1979;99:612-8. 10. Uchida A, Yiochi W, Osamu F, Takao M, Yokio I, Hiroshi 0. Controlled clinical evaluation of a 10% strontium chloride dentifrice in treatment of dentin hypersensitivity following periodontal surgery. J Periodontol 1980;51:578-81. 11. Nishida M, Katamsi D, Ucheda A, et al. Hypersensitivity of the exposed root surface after surgical periodontal treatment. J Osaka Univ Dent Sot 1976;16:73-7. 12. Federal Register 1982;47(101,Book 2):2271 l-930. 13. Stark M, Kempler D, Pelzner RB, Rosenfield J, Leung RL, Mintatos S. Rationalization of electric pulp-testing methods. ORAL
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14. McGrath P, Gracely R, Dubner R, Heft M. Nonpain and pain sensations evoked by tooth pulp stimulation. Pain 1983; 15:37788. 15. Seltzer S, Stock R, Marcus R, Jackson E. Alteration of human
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pain thresholds by nutritional manipulation and L-tryptophane supplementation. Pain 1982;13:385-93. 16. Mazur B, Massler M. Influence of periodontal disease on the dental pulp. ORAL SURG ORAL MED ORAL PATHOL 1964; 17:592-603. 17. Bergenholtz G, Lindhe J. Effect of experimental induced marginal periodontitis and periodontal scaling on the dental pulp. J Clin Periodontol 1978;5:59-73.
Tooth sensitivity Reprint requests to: Dr. James A. Wallace Graduate Endodontics School of Dentistry Case Western Reserve 2123 Abington Rd. Cleveland, OH 44106
and periodontal
Program University
therapy
747
