0099-2399/91/1709-0461/$03.00/0 JOURNAL OF ENDODONTICS Copyright 9 1991 by The American Association of Endodontists
Printed in U.S.A.
VOL. 17, NO. 9, SEPTEMBER1991
CLINICAL ARTICLE A Comparison of Anxiety Levels Associated with Root Canal Therapy and Oral Surgery Treatment Marston Wong, DDS, MS, and W. Reed Lytle, DDS
need for a viable public awareness program but strongly suggest that the clinician needs to provide a positive dental experience.
Questionnaires regarding experience, hearsay, and perceptions of anxiety toward eight dental treatments were distributed to a general patient population. Data revealed that among 349 respondents 35% heard that root canal therapy was the most unpleasant dental treatment, whereas 29% listed oral surgery treatment as having the worst reputation. However, 53% of those experiencing oral surgery treatment stated that an oral surgery treatment was the most unpleasant treatment whereas only 17% experiencing root canal therapy stated the same for root canal therapy. On the basis of anxiety scores, root canal therapy and oral surgery treatment were categorized in the high-anxiety category, crowns, dentures, and fillings in the moderate-anxiety category, and cleaning, sick call, and examination in the low-anxiety category. The anxiety levels of root canal therapy and oral surgery treatment were then analyzed as they related to different experience groups (combinations of root canal therapy and oral surgery experience), hearsay experience, and most unpleasant experience with root canal therapy and oral surgery. Patients having experience with root canal therapy or oral surgery treatment had lower anxiety levels toward these respective treatments than did those who had no such experience. Patients who have heard negative stories (hearsay) of root canal therapy and oral surgery showed higher levels of anxiety toward these respective treatments than did those who have not heard such stories. But former endodontic patients who had heard negative stories about root canal therapy actually recorded lower anxiety levels toward root canal therapy than those patients with no negative hearsay experience. Similarly, former oral surgery patients who had heard negative stories of oral surgery treatment recorded the same levels of anxiety toward oral surgery as those who had no negative hearsay experience of oral surgery treatment. Findings from this study not only reinforce the
The putative statement "I'd rather have a baby than go to the dentist," suggests one segment of the public's supposedly negative perception and accompanying anxiety concerning dental treatment. In the United States it has been estimated that approximately 80% of the population has some anxiety about dental treatment and that 5 to 14% have an extreme degree of dental treatment anxiety (1). Research on dental anxiety has involved samples that included dental phobics and high- and low-anxiety patients as well as patients from the general population. Investigations on the subject of dental anxiety have looked at various background factors that contribute to anxiety, such as vicarious experiences (hearsay) through significant others (i-3) and past traumatic dental experiences (1, 4). Studies have also involved clinical factors like types of dental procedures (anesthetic injection and drilling) (4-6) and the behavioral mannerism of the dentist (1, 47). A patient's perception of a dental procedure has also been observed as a factor which contributes to the overall anxiety a patient has toward dental treatment. Kleinknecht et al. (4) found that just the sights and sounds of the drill evoked high anxiety levels among anxious patients. These patients responded to perceptions they brought to the dental situation. Similarly, patients may view dental treatment not as a sum of several separate procedures but conceptually as one single treatment. In other words, the anxious patient perceives the whole root canal therapy appointment as being anxiety arousing. The words "root canal treatment" or "wisdom tooth extraction" evoke certain general thoughts that may be anxiety laden. To date, very little research documentation is available on the subject of patient anxiety concerning specific dental treatments, especially root canal therapy and extractions. Berggren and Meynert (5) found that 160 dental phobics ranked extractions as fourth and endodontic treatment as seventh among dental events that were the most fear arousing. Dental procedures related to some sort of drilling or aspects of
461
462
Journal of Endodontics
Wong and Lytle
anesthetic injection made up the rest of the list. Molin and Seeman (6) found similar results. Among 10 specified elements in dental treatment, extraction was listed as the second and endodontic treatment as the fourth most anxiety-provoking by 19 dental phobics. Drilling and anesthetic injections ranked first and third, respectively. Oral surgery treatment and root canal therapy were listed as the top two fear-arousing treatments among dental phobics. Rankin and Harris (3) found that among 250 dental patients, the following dental treatments were listed in descending order of bad experiences: difficult extraction, restoration placed, periodontal treatment, prosthodontic treatment, and orthodontic treatment. Interestingly, root canal therapy was not listed. LeClaire et al. (8) found that 44% of the subjects reported a decrease in fearfulness to endodontic procedures as a result of experiencing root canal therapy. The aim of this study was to compare the degrees of anxiety towards root canal therapy and oral surgery treatment. In order to accomplish this task, patients were asked to rank eight types of dental treatments according to anxiety levels, frequency of hearsay as to the most unpleasant treatment, and personal experience as to the most unpleasant treatment. Then, the relationship between patients' anxiety levels toward root canal therapy and oral surgery treatment and experience, hearsay, and most unpleasant dental experience of root canal therapy and oral surgery treatment were analyzed.
RESULTS Of the 410 questionnaires distributed, 349 were returned (85%); 243 respondents were males, 58 were females, 48 did not state their gender, 271 were under 30 yr of age, and 78 were 30 yr or over. Table 1 presents data on the frequency of hearsay and most unpleasant experience with various dental treatments. The table suggests that, on the basis of hearsay, approximately the same percentage of patients listed root canal therapy and oral surgery as being the most painful dental treatment (35 and 29%, respectively). However, when patients were asked what was the most unpleasant treatment they had experienced, oral surgery ranked first among the eight different treatments. Approximately 53% of those people who underwent extrac-
FILL IN A g e
CIRCLE Sex: Male / Female
Check the treatments below which you have EXPERIEN(;ED.
Sick Call Cleaning Annual Exam . . . . . Dentures .....
Fillings
___Root
Canal
. . . . . . Caps/Crowns/Bridge Tooth Extraction/ Surgery __Don't Know
The most unpleasant dental situation you have HEARD about involved what type of dental treatment?
M A T E R I A L S AND M E T H O D S From your own experience,what situation or type of dental work was
the most unpleasant?
Questionnaires relating to hearsay, experience, and perceptions of anxiety levels toward different dental treatments were distributed for 5 consecutive days at the reception desks of four dental clinics at a military base. After checking in, each patient was given a survey and was asked to answer the questions and return it to the desk before leaving the clinic. No assistance or information was given by the staff in answering any particular survey question. Each questionnaire was controlled by an assigned number. The questionnaire consisted of four questions (Fig. 1) and is self-explanatory, Data concerning the frequency of responses to any experience, hearsay and most unpleasant experience with different treatment types was recorded. Anxiety levels for treatment types were compared. Anxiety levels for treatment types by age and gender were also analyzed. Additional variables of hearsay and most unpleasant experience of root canal therapy and oral surgery, as well as combinations of any experience of root canal therapy and/or oral surgery (experience groups) were analyzed as they related to anxiety scores for root canal therapy and oral surgery treatments. The scope of the study did not consider gender and age as variables in these comparisons between anxiety levels toward root canal therapy and oral surgery treatment. Because of the ordinal nature of the data regarding anxiety levels, the statistical analysis was performed by using a nonparametric test (Kruskal-Wallis) (9). Statistical analysis tested the general hypothesis Ho: There is no difference between the groups in their anxiety levels for a given procedure H~: there is a difference between the groups in their anxiety levels for a given procedure. This hypothesis was tested at a level of significance of 0.05.
ANXIETY LEVEL NONE 1
A LITTLE 2
SOMEWHAT 3
VERY 4
EXTREME 5
Using the scale above, please enter the number that corresponds to your anxiety level for the following treatments. Sick Call _Cleaning Annual Exam Dentures ___Fillings
Root Canal
_Caps/Crowns/Bridge Tooth Extraction/ Surgery Don't Know
FIG 1. Sample questionnaire relating to hearsay, experience, and perceptions of anxiety levels toward dental treatments.
TABLE 1. Frequency of hearsay, any experience, and most unpleasant experience (worst experience) with treatment type Treatment Root canal Extractions Fillings Caps Dentures Cleaning Examination Sick call
Hearsay Frequency* 123 102 7 2 2 ----
(35) (29) (0.02) (0.005) (0.005) (--) (--) (--)
Any Experience Frequency* 52 116 184 47 14 181 166 147
(15) (33) (53) (13) (4) (52) (48) (42)
Worst Experience Frequencyt 9 6 26 6 -15 ---
(17) (53) (14) (3) (--) (8) (--) (--)
* Valuesin parenthesesare the percentages of all respondents;n = 349. t Valuesin parenthesesare the percentagesof patientshavingthat type of treatment.
Anxiety and Root Canal Therapy
Vol. 17, No. 9, September 1991
tions stated that it was the most painful dental treatment they had experienced. Only 17% of those who had experienced root canal therapy stated that the treatment was the most unpleasant. Tables 2 to 5 present data on the mean anxiety levels for various dental treatments. To evaluate the data, the Statistical Analysis System Univariate procedure was used (8). A normality plot, as well as skewness and kurtosis, was examined. In each case, evidence was sufficient to reject the assumption that the data were samples from normal distributions. For this reason and because of the ordinal nature of the data, the statistical analysis was performed with a nonparametric test (Kruskat-Wallis). Rather than to present contingency tables for every comparison, for simplification of data presentation, anxiety levels are presented as mean scores. In this way, the reader is able, at a glance, to have a relative comparison of anxiety levels associated with different dental treatments. Anxiety is a self-perception variable measured on a scale ranging from none or 1 to extreme or 5. In Table 2, this variable was then collapsed into three categories: low (anxiety score of 2.0 or less), moderate (anxiety score of 2.1 to 3.0), and high (anxiety score of greater than 3.0). In looking at the eight treatments, it was noted that root canal therapy and oral surgery fell into the high-anxiety category, crowns, dentures, and fillings fell into the moderate-anxiety category, and cleaning, sick call, and annual exam fell into the low-anxiety category. Significant differences in anxiety levels were observed between the low-, moderate-, and high-anxiety treatment groups. No significant differences were found between treatments within the moderate- or high-anxiety treatment groups. In the low-anxiety treatment group, however, cleaning and exam anxiety levels were significantly different. When comparing anxiety levels of the eight dental treatments by gender and age, no significant differences were observed except for cleaning, sick call, and examination treatments, where females recorded higher anxiety levels than did males. Because the data revealed root canal therapy and oral surgery treatment as being associated with high anxiety levels, further comparisons were made of these two treatment types with regard to dental treatment experience groups, hearsay experience, and most unpleasant experience. Table 3 presents data on the anxiety scores of patients for root canal therapy and oral surgery treatment as they relate to dental treatment experience. Overall, patients recorded similar anxiety levels (3.4) for root canal therapy and oral surgery treatments. However, differences in anxiety levels for root canal therapy and oral surgery treatment were found when the overall groups were divided into different experience groups. For anxiety levels involving root canal therapy, patients who experienced root canal therapy only reflected lower anxiety levels (2.3) than did patients who experienced oral surgery with (3.2) or without (3.5) root canal therapy experience. They also had lower anxiety levels than did patients who had no experience with either root canal therapy or oral surgery (3.6). Similarly, patients who experienced only oral surgery treatment had lower anxiety levels (3.1) toward oral surgery than did patients who had no experience with either oral surgery or root canal therapy (3.6). Table 4 presents data on the anxiety levels of patients for root canal therapy and oral surgery treatment by hearsay experience and most unpleasant experience. People who have heard negative stories about root canal therapy and oral surgery treatment show a higher level of anxiety toward these
463
TABLE 2. Anxiety scores for dental treatments* Appointment High anxietyt Root canal Extractions Moderate anxietyt Caps/crowns Dentures Fillings Low anxietyt,:t. Cleaningw Sick call Examinationw
Overall
Male
Female
< 3 0 yr
>30 yr
3.4 (213)3.4 (148) 3.6 (37) 3.4 (167) 3.3 (46) 3.4 (238) 3.3 (162) 3.5 (43) 3.4 (185) 3.3 (53) 2.6 (195) 2.6 (140) 3.0 (31) 2.6 (155) 2.5 (40) 2.5 (163) 2.4 (117) 2.7 (27) 2.5 (128) 2.4 (35) 2.4 (256) 2.3 (173) 2.7 (46) 2.3 (201) 2.6 (55) 1.9 (256) 1.9 (170) 2.3 (45) 1.9 (198) 2.2 (58) 1.8 (236) 1.7 (164) 2.4 (39) 1.8 (186) 2.0 (50) 1.6 (245) 1.5 (168) 1.9 (39) 1.5 (194) 1.7 (51)
* Valuesin parenthesesrepresenttotal number. / Statisticalsignificancebetweenanxietylevelgroups(p < 0.05). :~Statisticalsignificancebetweengenders(p < 0.05).Not all respondentsidentifiedtheir
gender. wStatisticalsignificancewithinanxietylevelgroup(p < 0.05).
TABLE 3. Comparison of anxiety scores for root canal therapy and oral surgery treatment by experience group Experience Group* A. B. C. D. E.
OS and RCT OS and no RCT no OS and RCT no OS and no RCT Overall
Root Canal Therapyt
(n)
Oral Surgery:l:
(n)
3.2 3.5 2.3 3.6 3.4
(27) (53) (14) (119) (213)
3.3 3.1 2.6 3.6 3.4
(27) (75) (08) (128) (238)
* os, oral surgery;RCT,root canaltherapy. 1Group C versusgroup A, groupC versus group B, and group C versusgroup D, significantdifference(p < 0.05), :~GroupB versusgroupD, significantdifference(p < 005).
TABLE 4. Anxiety levels for root canal therapy and oral surgery treatment by hearsay/most unpleasant (worst) experience Type of Experience
Anxiety Level (RCT)*
(n)
Anxiety Level (OS)*
(n)
Hearsayt No hearsay-I" Worst experience$ No worst experience$
3.7 3.2 3.4 3.5
(88) (125) (07) (160)
3.6 3.2 3.2 3.5
(81) (157) (58) (95)
*OS, oral surgery;RCT, root canaltherapy. 1 HearsayversusNo Hearsay,significantdifference(p < 0.05). :~Worst ExperienceversusNo Worst Experience,no significantdifference.
TABLE 5. Anxiety levels for root canal therapy and oral surgery treatment and hearsay/most unpleasant (worst) experience by experience group
Experience Group*
A. B. C. D.
OSandRCT OS and no RCT no OS and RCT no OS and no RCT
Anxiety Level with Hearsay Experience
Anxiety Level with Worst Experience
RCTI-(n)
OS:~ (n)
RCT(n)
OS(n)
3.1(08) 3.9 (29) 2.4 (07) 3.8 (44)
3.7(11) 2.8 (25) 3.0 (02) 4.1 (43)
4.2(04) NAw 2.3 (03) NA(0)
3.3(09) 3.2 (49) NA(0) NA(0)
* OS, oral surgery;RCT,root canaltherapy. t GroupC versusgroupB and groupC versusgroupD, significantdifference(p < 0.05). :~Group8 versusgroupD, significantdifference(p < 0.05). wNA, not applicable.
464
Journal of Endodontics
Wong and Lytle
respective treatments than do those who have not. However, no significant difference in anxiety levels was found between patients who had a most unpleasant experience with these treatments and those who had no such experience. Table 5 presents data on the anxiety leveIs of those who had hearsay experience and those who had a most unpleasant experience with root canal therapy and oral surgery treatment as they relate to different dental treatment experience groups. Patients who heard that root canal therapy was the most unpleasant dental treatment but who had not experienced root canal therapy recorded higher anxiety levels toward root canal therapy (3.8 and 3.9) than did former endodontic patients who had negative hearsay experiences of root canal therapy and had experienced root canal therapy (2.4). In fact, this latter group had anxiety levels lower than those of patients who had not heard root canal therapy was the most unpleasant (3.2) (Table 4). Among patients who had heard that oral surgery treatment was the most unpleasant, former oral surgery patients reported lower anxiety levels (2.8) toward oral surgery treatment than did those patients with no oral surgery or root canal therapy experience (4.1). The former also showed anxiety levels similar to but not statistically different from those with no hearsay experience (3.2) (Table 4).
DISCUSSION
Anxiety Levels for Eight Types of Dental Treatments To our knowledge, no previous study has ranked dental treatments by degree of anxiety level as was done in this study. The findings of this study clearly demonstrate that anxiety levels vary by dental treatment. They further substantiate the clinician's impression that root canal therapy and oral surgery treatment are the most anxiety evoking treatments. When the factors of gender and age were analyzed, no significant differences were observed for dental treatments in the high and moderate anxiety category (Table 1). These findings are consistent with those of Rankin and Harris (3). Only for dental treatments in the low anxiety category (cleaning, sick call, examination) was a gender difference noted where female patients were more anxious. Other studies (1, 4) have found similar findings when comparing high-anxiety patients with low-anxiety patients. These findings suggest that the clinician should view patients according to the type of dental treatment they are undergoing. To label a patient as an apprehensive dental patient and assume that the patient has the same level of anxiety for all treatments may be incorrect. Previous research has looked at specific procedures, such as anesthetic injection and drilling, as major factors in contributing to dental anxiety. The implication is that if these specific procedures are addressed by the clinician, patient anxiety can be significantly alleviated. Results from this study show that although injections and drilling are common procedures performed in fillings and root canal therapy, the anxiety levels for each treatment is different. In fact, denture treatment fell in the same anxiety category as fillings, yet this type of treatment often does not include injections or drilling. The clinician must be cognizant of these differences in patients' perceptions of treatments and alter patient management techniques accordingly.
The Negative Perception of Root Canal Therapy and Oral Surgery Treatment In 1984, the American Association of Endodontists conducted a survey (I0) and found that although 23% of the public had experienced root canal therapy, 52% had the opinion that root canal therapy was somewhat or extremely painful. The survey showed that the general perception of root canal therapy is negative. Although only 15% of those polled in study presented here had any experience with root canal therapy, 35% stated that they had heard that root canal therapy was the most unpleasant dental experience. When one considers that seven times as many people experienced oral surgery treatment as being their most unpleasant experience compared with root canal therapy (62 versus 9, respectively) (Table 1), the impact of the negative perception of root canal therapy becomes evident. Although the negative perception of root canal therapy is disproportionate when compared with oral surgery, it must be noted that one in seven experiencing root canal therapy still perceived it to be the most unpleasant dental experience. If pain (including postoperative pain) is to be considered a significant factor in unpleasantness, then this finding is in agreement with Peters (11), who found the incidence of severe postoperative pain to be 9 to 16% during and after treatment. However, for the majority of patients in our study, root canal treatment was not the most unpleasant dental procedure. Findings in this study corroborate the survey of the American Association of Endodontists and support the Public Awareness Program's goals and strategy of counteracting the undeserved negative perception of root canal therapy. Fear of the unknown and fear of pain (12) have been documented as major reasons for anxiety. Through the Public Awareness Program, education of the public can help to reverse this negative image, especially for those with no experience of root canal therapy.
Hearsay and Most Unpleasant Experience as Factors Associated with Anxiety Previous studies have asked respondents to associate hearsay (1, 2) and past traumatic dental experiences (2, 5, 6) to their present fear of dental procedures. By comparing lowfear group responses to those of the high-fear group, a higher number of responses in the high-fear group (dental phobics) have implicated hearsay and past experience as etiological factors in dental fear. In the study reported here, a different approach was taken. Instead, changes in anxiety levels toward root canal therapy and oral surgery treatment were evaluated with regard to the presence or absence of hearsay and most unpleasant experience with root canal therapy and oral surgery treatment. Results from this study corroborate previous studies (1, 2) that have associated hearsay with fear of dental procedures. Significant differences in anxiety levels were noted between patients who had heard that root canal treatment was the most unpleasant experience (3.7) and those who had not (3.2) (Table 4). Similarly, patients who had heard oral surgery treatment was unpleasant recorded higher anxiety levels (3.6) than did those who had not (3.2). It must be emphasized that although hearsay may significantly impact on anxiety levels, even without this factor, root
Vol. 17, No. 9, September 1991
canal therapy and oral surgery treatment may evoke high anxiety levels (3.2 for both treatments) (Table 4). Explanations for such high anxiety levels may lie in the possibility that patients bring with them certain preconceived perceptions of the dental situation. In so doing, the patient reacts to the perceptions rather than to the physical sensations (2). Although other studies (5, 6) have associated past traumatic dental experiences with dental fear, findings from this study could not corroborate such a relationship. It should be noted, however, that the small sample size and the influence of hearsay may have contributed to this finding. Still, findings from this study corroborate those of Shoben and Borland (2) who did not find the frequency of traumatic dental experience to be a distinguishing factor between high- and low-fear groups. Experience with Root Canal Therapy and Oral Surgery Treatment as Factors Associated with Anxiety
Experience with root canal therapy or oral surgery treatment may diminish the anxiety levels of patients with these treatments. This attenuating effect may be greater with root canal therapy. Former endodontic patients with no oral surgery treatment experience showed significantly lower anxiety levels (2.3) towards root canal therapy than did other dental treatment experience groups (Table 3). The anxiety level was similar to the anxiety levels for fillings, crowns, and dentures (moderate anxiety). Similarly, former oral surgery patients with no root canal treatment experience had lower anxiety levels (3.1) toward oral surgery treatment than did patients with no experience with oral surgery or root canal treatment (Table 3). However, the anxiety levels of the former group still could be considered to be in the high-anxiety category. A similar trend in anxiety levels among different dental treatment experience groups was seen when patients with hearsay experience of root canal therapy and oral surgery were analyzed. Former endodontic patients without oral surgery treatment experience who had heard that root canal therapy was the most unpleasant dental procedure recorded lower anxiety levels (2.4) (Table 5) than did patients who had not heard root canal therapy to be the most unpleasant (3.2) (Table 4). Also, former oral surgery patients with no root canal therapy experience but with hearsay experience showed anxiety levels (2.8) (Table 5) similar to, but not lower than, patients with no hearsay experience (3.2) (Table 4). These findings suggest that in endodontics, and to a lesser extent oral surgery, experience may counteract the negative influence of hearsay on the anxiety level of patients. It also corroborates the study of LeClaire et al. (8), who found that 44% of patients having root canal therapy showed a decrease in fearfulness. The Clinician's Role
The clinician must first identify the apprehensive patient. This can be done simply by asking the patient "How anxious do you become when you have dental work?" (1) or "Are you anxious about having root canal therapy?" Insight into whether the patient is anxious can be obtained. Having identified the anxious patient, the clinician can play a major role
Anxiety and R o o t Canal Therapy
465
in the reduction of anxiety by being communicative and understanding and by providing information and assurances to control and prevent discomfort (13). Although LeClaire et al. (8) found that the local anesthetic injection, sensation of files introduced, working in the canals, and tapping or pushing on a sore tooth were ranked as the most unpleasant procedural aspects of root canal therapy, the dentist's "chairside" behavior can have a significant effect on patient anxiety. Among dental phobics, 45% attributed their fear not to painful treatment but to the "rough" treatment of a past dentist (5). Rankin and Harris (3) found that good experiences seem to attenuate the impact of bad experiences. The greatest contribution a dentist can make to reducing anxiety is to provide a positive experience and train the patient in the use of effective coping skills. Coping skills that have been suggested are hypnosis, controlled breathing, relaxation, distraction, and systemic desensitization (1, 14, 15). Thus, through compassionate, painless dentistry and by providing the patient with information and coping skills, the clinician may eliminate the effects of hearsay, prevent the occurrence of unpleasant experiences, and decrease overall patient anxiety. The patient may then become a messenger to others of the positive image of root canal therapy. The authors thank the staff at Headquarters, Test and Experimentation Command, Fort Hood, TX for their statistical support and Dr. Morrison Wong for his editorial assistance. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of Defense or the United States government. Dr. Wong is chief of endodontics and mentor in the Advanced Educational Program in General Dentistry (2 yr) at Fort Hood, TX. Dr. Lytle is General Dental Officer with the 92nd Medical Detachment (Dental Service), Hanau, Federal Republic of Germany. Address requests for reprints to COL Marston Wong, USA DENTAC, Frt. Hood, TX 76544-5063.
References 1. Scott DS, Hirschman R. Psychological aspects of dental anxiety in adults. J Am Dent Assoc 1982;104:27-31. 2. Shoben EJ, Borland L. An empirical study of the etiology of dental fears. J Clin Psycho11954;10:171-4. 3. Rankin JA, Harris MB. Dental anxiety: the patient's point of view. J Am Dent Assoc 1984;109:43-7. 4. Kleinknecht RA, Klepac RK, Alexander LD. Origins and characteristics of fear of dentistry. J Am Dent Assoc 1973;86:842-8. 5. Berggren U, Meynert G. Dental fear and avoidance: causes, symptoms and consequences. J Am Dent Assoc 1984;109:43-7. 6. Molin C, Seeman K. Disproportionate dental anxiety: clinical and nosological considerations. Acta Ondontol Scand 1970;28:197-212. 7. Gale EN. Fears of the dental situation. J Dent Res 1972;51:964-6. 8. LeClaire AJ, Skidmore AE, Griffin JA, Balaban FS. Endodontic fear survey. J Endodon 1988;14:560-4. 9. SAS/STAT Guide For Personal Computers. 6th ed. Gary, NC: SAS Institute Inc., 1987:713-25. 10. Public Education Report. Surveys document more people choosing root canal therapy over extractions. Chicago: American Association of Endodontists, April 1987:1-2. 11. Peters DD. Evaluation of prophylactic alveolar trephination to avoid pain. J Endodon 1980;6:519-26. 12. Hall N, Edmondson HD. The aetiology and psychology of dental fear. Br Dent J 1983;154:247-52. 13. Corah NL, O'Shea RM, Bissell GD, Thines TJ, Mendola P. The dentistpatient relationship: perceived dentist behaviors that reduce patient anxiety and increase satisfaction. J Am Dent Assoc 1988;116:73-6. 14. Corah NL, Gale EN, IIlig SJ. Psychological stress reduction during dental procedures. J Dent Res 1979;58:1347-51. 15. Kleinknecht RA, Thorndike RM, McGlynn TD, Hardavy J. Factor analysis of the dental fear survey with cross-validation. J Am Dent Assoc 1984;108:59-61.
Printed in U.S.A.
VOL. 17, NO. 9, SEPTEMBER1991
CLINICAL ARTICLE A Comparison of Anxiety Levels Associated with Root Canal Therapy and Oral Surgery Treatment Marston Wong, DDS, MS, and W. Reed Lytle, DDS
need for a viable public awareness program but strongly suggest that the clinician needs to provide a positive dental experience.
Questionnaires regarding experience, hearsay, and perceptions of anxiety toward eight dental treatments were distributed to a general patient population. Data revealed that among 349 respondents 35% heard that root canal therapy was the most unpleasant dental treatment, whereas 29% listed oral surgery treatment as having the worst reputation. However, 53% of those experiencing oral surgery treatment stated that an oral surgery treatment was the most unpleasant treatment whereas only 17% experiencing root canal therapy stated the same for root canal therapy. On the basis of anxiety scores, root canal therapy and oral surgery treatment were categorized in the high-anxiety category, crowns, dentures, and fillings in the moderate-anxiety category, and cleaning, sick call, and examination in the low-anxiety category. The anxiety levels of root canal therapy and oral surgery treatment were then analyzed as they related to different experience groups (combinations of root canal therapy and oral surgery experience), hearsay experience, and most unpleasant experience with root canal therapy and oral surgery. Patients having experience with root canal therapy or oral surgery treatment had lower anxiety levels toward these respective treatments than did those who had no such experience. Patients who have heard negative stories (hearsay) of root canal therapy and oral surgery showed higher levels of anxiety toward these respective treatments than did those who have not heard such stories. But former endodontic patients who had heard negative stories about root canal therapy actually recorded lower anxiety levels toward root canal therapy than those patients with no negative hearsay experience. Similarly, former oral surgery patients who had heard negative stories of oral surgery treatment recorded the same levels of anxiety toward oral surgery as those who had no negative hearsay experience of oral surgery treatment. Findings from this study not only reinforce the
The putative statement "I'd rather have a baby than go to the dentist," suggests one segment of the public's supposedly negative perception and accompanying anxiety concerning dental treatment. In the United States it has been estimated that approximately 80% of the population has some anxiety about dental treatment and that 5 to 14% have an extreme degree of dental treatment anxiety (1). Research on dental anxiety has involved samples that included dental phobics and high- and low-anxiety patients as well as patients from the general population. Investigations on the subject of dental anxiety have looked at various background factors that contribute to anxiety, such as vicarious experiences (hearsay) through significant others (i-3) and past traumatic dental experiences (1, 4). Studies have also involved clinical factors like types of dental procedures (anesthetic injection and drilling) (4-6) and the behavioral mannerism of the dentist (1, 47). A patient's perception of a dental procedure has also been observed as a factor which contributes to the overall anxiety a patient has toward dental treatment. Kleinknecht et al. (4) found that just the sights and sounds of the drill evoked high anxiety levels among anxious patients. These patients responded to perceptions they brought to the dental situation. Similarly, patients may view dental treatment not as a sum of several separate procedures but conceptually as one single treatment. In other words, the anxious patient perceives the whole root canal therapy appointment as being anxiety arousing. The words "root canal treatment" or "wisdom tooth extraction" evoke certain general thoughts that may be anxiety laden. To date, very little research documentation is available on the subject of patient anxiety concerning specific dental treatments, especially root canal therapy and extractions. Berggren and Meynert (5) found that 160 dental phobics ranked extractions as fourth and endodontic treatment as seventh among dental events that were the most fear arousing. Dental procedures related to some sort of drilling or aspects of
461
462
Journal of Endodontics
Wong and Lytle
anesthetic injection made up the rest of the list. Molin and Seeman (6) found similar results. Among 10 specified elements in dental treatment, extraction was listed as the second and endodontic treatment as the fourth most anxiety-provoking by 19 dental phobics. Drilling and anesthetic injections ranked first and third, respectively. Oral surgery treatment and root canal therapy were listed as the top two fear-arousing treatments among dental phobics. Rankin and Harris (3) found that among 250 dental patients, the following dental treatments were listed in descending order of bad experiences: difficult extraction, restoration placed, periodontal treatment, prosthodontic treatment, and orthodontic treatment. Interestingly, root canal therapy was not listed. LeClaire et al. (8) found that 44% of the subjects reported a decrease in fearfulness to endodontic procedures as a result of experiencing root canal therapy. The aim of this study was to compare the degrees of anxiety towards root canal therapy and oral surgery treatment. In order to accomplish this task, patients were asked to rank eight types of dental treatments according to anxiety levels, frequency of hearsay as to the most unpleasant treatment, and personal experience as to the most unpleasant treatment. Then, the relationship between patients' anxiety levels toward root canal therapy and oral surgery treatment and experience, hearsay, and most unpleasant dental experience of root canal therapy and oral surgery treatment were analyzed.
RESULTS Of the 410 questionnaires distributed, 349 were returned (85%); 243 respondents were males, 58 were females, 48 did not state their gender, 271 were under 30 yr of age, and 78 were 30 yr or over. Table 1 presents data on the frequency of hearsay and most unpleasant experience with various dental treatments. The table suggests that, on the basis of hearsay, approximately the same percentage of patients listed root canal therapy and oral surgery as being the most painful dental treatment (35 and 29%, respectively). However, when patients were asked what was the most unpleasant treatment they had experienced, oral surgery ranked first among the eight different treatments. Approximately 53% of those people who underwent extrac-
FILL IN A g e
CIRCLE Sex: Male / Female
Check the treatments below which you have EXPERIEN(;ED.
Sick Call Cleaning Annual Exam . . . . . Dentures .....
Fillings
___Root
Canal
. . . . . . Caps/Crowns/Bridge Tooth Extraction/ Surgery __Don't Know
The most unpleasant dental situation you have HEARD about involved what type of dental treatment?
M A T E R I A L S AND M E T H O D S From your own experience,what situation or type of dental work was
the most unpleasant?
Questionnaires relating to hearsay, experience, and perceptions of anxiety levels toward different dental treatments were distributed for 5 consecutive days at the reception desks of four dental clinics at a military base. After checking in, each patient was given a survey and was asked to answer the questions and return it to the desk before leaving the clinic. No assistance or information was given by the staff in answering any particular survey question. Each questionnaire was controlled by an assigned number. The questionnaire consisted of four questions (Fig. 1) and is self-explanatory, Data concerning the frequency of responses to any experience, hearsay and most unpleasant experience with different treatment types was recorded. Anxiety levels for treatment types were compared. Anxiety levels for treatment types by age and gender were also analyzed. Additional variables of hearsay and most unpleasant experience of root canal therapy and oral surgery, as well as combinations of any experience of root canal therapy and/or oral surgery (experience groups) were analyzed as they related to anxiety scores for root canal therapy and oral surgery treatments. The scope of the study did not consider gender and age as variables in these comparisons between anxiety levels toward root canal therapy and oral surgery treatment. Because of the ordinal nature of the data regarding anxiety levels, the statistical analysis was performed by using a nonparametric test (Kruskal-Wallis) (9). Statistical analysis tested the general hypothesis Ho: There is no difference between the groups in their anxiety levels for a given procedure H~: there is a difference between the groups in their anxiety levels for a given procedure. This hypothesis was tested at a level of significance of 0.05.
ANXIETY LEVEL NONE 1
A LITTLE 2
SOMEWHAT 3
VERY 4
EXTREME 5
Using the scale above, please enter the number that corresponds to your anxiety level for the following treatments. Sick Call _Cleaning Annual Exam Dentures ___Fillings
Root Canal
_Caps/Crowns/Bridge Tooth Extraction/ Surgery Don't Know
FIG 1. Sample questionnaire relating to hearsay, experience, and perceptions of anxiety levels toward dental treatments.
TABLE 1. Frequency of hearsay, any experience, and most unpleasant experience (worst experience) with treatment type Treatment Root canal Extractions Fillings Caps Dentures Cleaning Examination Sick call
Hearsay Frequency* 123 102 7 2 2 ----
(35) (29) (0.02) (0.005) (0.005) (--) (--) (--)
Any Experience Frequency* 52 116 184 47 14 181 166 147
(15) (33) (53) (13) (4) (52) (48) (42)
Worst Experience Frequencyt 9 6 26 6 -15 ---
(17) (53) (14) (3) (--) (8) (--) (--)
* Valuesin parenthesesare the percentages of all respondents;n = 349. t Valuesin parenthesesare the percentagesof patientshavingthat type of treatment.
Anxiety and Root Canal Therapy
Vol. 17, No. 9, September 1991
tions stated that it was the most painful dental treatment they had experienced. Only 17% of those who had experienced root canal therapy stated that the treatment was the most unpleasant. Tables 2 to 5 present data on the mean anxiety levels for various dental treatments. To evaluate the data, the Statistical Analysis System Univariate procedure was used (8). A normality plot, as well as skewness and kurtosis, was examined. In each case, evidence was sufficient to reject the assumption that the data were samples from normal distributions. For this reason and because of the ordinal nature of the data, the statistical analysis was performed with a nonparametric test (Kruskat-Wallis). Rather than to present contingency tables for every comparison, for simplification of data presentation, anxiety levels are presented as mean scores. In this way, the reader is able, at a glance, to have a relative comparison of anxiety levels associated with different dental treatments. Anxiety is a self-perception variable measured on a scale ranging from none or 1 to extreme or 5. In Table 2, this variable was then collapsed into three categories: low (anxiety score of 2.0 or less), moderate (anxiety score of 2.1 to 3.0), and high (anxiety score of greater than 3.0). In looking at the eight treatments, it was noted that root canal therapy and oral surgery fell into the high-anxiety category, crowns, dentures, and fillings fell into the moderate-anxiety category, and cleaning, sick call, and annual exam fell into the low-anxiety category. Significant differences in anxiety levels were observed between the low-, moderate-, and high-anxiety treatment groups. No significant differences were found between treatments within the moderate- or high-anxiety treatment groups. In the low-anxiety treatment group, however, cleaning and exam anxiety levels were significantly different. When comparing anxiety levels of the eight dental treatments by gender and age, no significant differences were observed except for cleaning, sick call, and examination treatments, where females recorded higher anxiety levels than did males. Because the data revealed root canal therapy and oral surgery treatment as being associated with high anxiety levels, further comparisons were made of these two treatment types with regard to dental treatment experience groups, hearsay experience, and most unpleasant experience. Table 3 presents data on the anxiety scores of patients for root canal therapy and oral surgery treatment as they relate to dental treatment experience. Overall, patients recorded similar anxiety levels (3.4) for root canal therapy and oral surgery treatments. However, differences in anxiety levels for root canal therapy and oral surgery treatment were found when the overall groups were divided into different experience groups. For anxiety levels involving root canal therapy, patients who experienced root canal therapy only reflected lower anxiety levels (2.3) than did patients who experienced oral surgery with (3.2) or without (3.5) root canal therapy experience. They also had lower anxiety levels than did patients who had no experience with either root canal therapy or oral surgery (3.6). Similarly, patients who experienced only oral surgery treatment had lower anxiety levels (3.1) toward oral surgery than did patients who had no experience with either oral surgery or root canal therapy (3.6). Table 4 presents data on the anxiety levels of patients for root canal therapy and oral surgery treatment by hearsay experience and most unpleasant experience. People who have heard negative stories about root canal therapy and oral surgery treatment show a higher level of anxiety toward these
463
TABLE 2. Anxiety scores for dental treatments* Appointment High anxietyt Root canal Extractions Moderate anxietyt Caps/crowns Dentures Fillings Low anxietyt,:t. Cleaningw Sick call Examinationw
Overall
Male
Female
< 3 0 yr
>30 yr
3.4 (213)3.4 (148) 3.6 (37) 3.4 (167) 3.3 (46) 3.4 (238) 3.3 (162) 3.5 (43) 3.4 (185) 3.3 (53) 2.6 (195) 2.6 (140) 3.0 (31) 2.6 (155) 2.5 (40) 2.5 (163) 2.4 (117) 2.7 (27) 2.5 (128) 2.4 (35) 2.4 (256) 2.3 (173) 2.7 (46) 2.3 (201) 2.6 (55) 1.9 (256) 1.9 (170) 2.3 (45) 1.9 (198) 2.2 (58) 1.8 (236) 1.7 (164) 2.4 (39) 1.8 (186) 2.0 (50) 1.6 (245) 1.5 (168) 1.9 (39) 1.5 (194) 1.7 (51)
* Valuesin parenthesesrepresenttotal number. / Statisticalsignificancebetweenanxietylevelgroups(p < 0.05). :~Statisticalsignificancebetweengenders(p < 0.05).Not all respondentsidentifiedtheir
gender. wStatisticalsignificancewithinanxietylevelgroup(p < 0.05).
TABLE 3. Comparison of anxiety scores for root canal therapy and oral surgery treatment by experience group Experience Group* A. B. C. D. E.
OS and RCT OS and no RCT no OS and RCT no OS and no RCT Overall
Root Canal Therapyt
(n)
Oral Surgery:l:
(n)
3.2 3.5 2.3 3.6 3.4
(27) (53) (14) (119) (213)
3.3 3.1 2.6 3.6 3.4
(27) (75) (08) (128) (238)
* os, oral surgery;RCT,root canaltherapy. 1Group C versusgroup A, groupC versus group B, and group C versusgroup D, significantdifference(p < 0.05), :~GroupB versusgroupD, significantdifference(p < 005).
TABLE 4. Anxiety levels for root canal therapy and oral surgery treatment by hearsay/most unpleasant (worst) experience Type of Experience
Anxiety Level (RCT)*
(n)
Anxiety Level (OS)*
(n)
Hearsayt No hearsay-I" Worst experience$ No worst experience$
3.7 3.2 3.4 3.5
(88) (125) (07) (160)
3.6 3.2 3.2 3.5
(81) (157) (58) (95)
*OS, oral surgery;RCT, root canaltherapy. 1 HearsayversusNo Hearsay,significantdifference(p < 0.05). :~Worst ExperienceversusNo Worst Experience,no significantdifference.
TABLE 5. Anxiety levels for root canal therapy and oral surgery treatment and hearsay/most unpleasant (worst) experience by experience group
Experience Group*
A. B. C. D.
OSandRCT OS and no RCT no OS and RCT no OS and no RCT
Anxiety Level with Hearsay Experience
Anxiety Level with Worst Experience
RCTI-(n)
OS:~ (n)
RCT(n)
OS(n)
3.1(08) 3.9 (29) 2.4 (07) 3.8 (44)
3.7(11) 2.8 (25) 3.0 (02) 4.1 (43)
4.2(04) NAw 2.3 (03) NA(0)
3.3(09) 3.2 (49) NA(0) NA(0)
* OS, oral surgery;RCT,root canaltherapy. t GroupC versusgroupB and groupC versusgroupD, significantdifference(p < 0.05). :~Group8 versusgroupD, significantdifference(p < 0.05). wNA, not applicable.
464
Journal of Endodontics
Wong and Lytle
respective treatments than do those who have not. However, no significant difference in anxiety levels was found between patients who had a most unpleasant experience with these treatments and those who had no such experience. Table 5 presents data on the anxiety leveIs of those who had hearsay experience and those who had a most unpleasant experience with root canal therapy and oral surgery treatment as they relate to different dental treatment experience groups. Patients who heard that root canal therapy was the most unpleasant dental treatment but who had not experienced root canal therapy recorded higher anxiety levels toward root canal therapy (3.8 and 3.9) than did former endodontic patients who had negative hearsay experiences of root canal therapy and had experienced root canal therapy (2.4). In fact, this latter group had anxiety levels lower than those of patients who had not heard root canal therapy was the most unpleasant (3.2) (Table 4). Among patients who had heard that oral surgery treatment was the most unpleasant, former oral surgery patients reported lower anxiety levels (2.8) toward oral surgery treatment than did those patients with no oral surgery or root canal therapy experience (4.1). The former also showed anxiety levels similar to but not statistically different from those with no hearsay experience (3.2) (Table 4).
DISCUSSION
Anxiety Levels for Eight Types of Dental Treatments To our knowledge, no previous study has ranked dental treatments by degree of anxiety level as was done in this study. The findings of this study clearly demonstrate that anxiety levels vary by dental treatment. They further substantiate the clinician's impression that root canal therapy and oral surgery treatment are the most anxiety evoking treatments. When the factors of gender and age were analyzed, no significant differences were observed for dental treatments in the high and moderate anxiety category (Table 1). These findings are consistent with those of Rankin and Harris (3). Only for dental treatments in the low anxiety category (cleaning, sick call, examination) was a gender difference noted where female patients were more anxious. Other studies (1, 4) have found similar findings when comparing high-anxiety patients with low-anxiety patients. These findings suggest that the clinician should view patients according to the type of dental treatment they are undergoing. To label a patient as an apprehensive dental patient and assume that the patient has the same level of anxiety for all treatments may be incorrect. Previous research has looked at specific procedures, such as anesthetic injection and drilling, as major factors in contributing to dental anxiety. The implication is that if these specific procedures are addressed by the clinician, patient anxiety can be significantly alleviated. Results from this study show that although injections and drilling are common procedures performed in fillings and root canal therapy, the anxiety levels for each treatment is different. In fact, denture treatment fell in the same anxiety category as fillings, yet this type of treatment often does not include injections or drilling. The clinician must be cognizant of these differences in patients' perceptions of treatments and alter patient management techniques accordingly.
The Negative Perception of Root Canal Therapy and Oral Surgery Treatment In 1984, the American Association of Endodontists conducted a survey (I0) and found that although 23% of the public had experienced root canal therapy, 52% had the opinion that root canal therapy was somewhat or extremely painful. The survey showed that the general perception of root canal therapy is negative. Although only 15% of those polled in study presented here had any experience with root canal therapy, 35% stated that they had heard that root canal therapy was the most unpleasant dental experience. When one considers that seven times as many people experienced oral surgery treatment as being their most unpleasant experience compared with root canal therapy (62 versus 9, respectively) (Table 1), the impact of the negative perception of root canal therapy becomes evident. Although the negative perception of root canal therapy is disproportionate when compared with oral surgery, it must be noted that one in seven experiencing root canal therapy still perceived it to be the most unpleasant dental experience. If pain (including postoperative pain) is to be considered a significant factor in unpleasantness, then this finding is in agreement with Peters (11), who found the incidence of severe postoperative pain to be 9 to 16% during and after treatment. However, for the majority of patients in our study, root canal treatment was not the most unpleasant dental procedure. Findings in this study corroborate the survey of the American Association of Endodontists and support the Public Awareness Program's goals and strategy of counteracting the undeserved negative perception of root canal therapy. Fear of the unknown and fear of pain (12) have been documented as major reasons for anxiety. Through the Public Awareness Program, education of the public can help to reverse this negative image, especially for those with no experience of root canal therapy.
Hearsay and Most Unpleasant Experience as Factors Associated with Anxiety Previous studies have asked respondents to associate hearsay (1, 2) and past traumatic dental experiences (2, 5, 6) to their present fear of dental procedures. By comparing lowfear group responses to those of the high-fear group, a higher number of responses in the high-fear group (dental phobics) have implicated hearsay and past experience as etiological factors in dental fear. In the study reported here, a different approach was taken. Instead, changes in anxiety levels toward root canal therapy and oral surgery treatment were evaluated with regard to the presence or absence of hearsay and most unpleasant experience with root canal therapy and oral surgery treatment. Results from this study corroborate previous studies (1, 2) that have associated hearsay with fear of dental procedures. Significant differences in anxiety levels were noted between patients who had heard that root canal treatment was the most unpleasant experience (3.7) and those who had not (3.2) (Table 4). Similarly, patients who had heard oral surgery treatment was unpleasant recorded higher anxiety levels (3.6) than did those who had not (3.2). It must be emphasized that although hearsay may significantly impact on anxiety levels, even without this factor, root
Vol. 17, No. 9, September 1991
canal therapy and oral surgery treatment may evoke high anxiety levels (3.2 for both treatments) (Table 4). Explanations for such high anxiety levels may lie in the possibility that patients bring with them certain preconceived perceptions of the dental situation. In so doing, the patient reacts to the perceptions rather than to the physical sensations (2). Although other studies (5, 6) have associated past traumatic dental experiences with dental fear, findings from this study could not corroborate such a relationship. It should be noted, however, that the small sample size and the influence of hearsay may have contributed to this finding. Still, findings from this study corroborate those of Shoben and Borland (2) who did not find the frequency of traumatic dental experience to be a distinguishing factor between high- and low-fear groups. Experience with Root Canal Therapy and Oral Surgery Treatment as Factors Associated with Anxiety
Experience with root canal therapy or oral surgery treatment may diminish the anxiety levels of patients with these treatments. This attenuating effect may be greater with root canal therapy. Former endodontic patients with no oral surgery treatment experience showed significantly lower anxiety levels (2.3) towards root canal therapy than did other dental treatment experience groups (Table 3). The anxiety level was similar to the anxiety levels for fillings, crowns, and dentures (moderate anxiety). Similarly, former oral surgery patients with no root canal treatment experience had lower anxiety levels (3.1) toward oral surgery treatment than did patients with no experience with oral surgery or root canal treatment (Table 3). However, the anxiety levels of the former group still could be considered to be in the high-anxiety category. A similar trend in anxiety levels among different dental treatment experience groups was seen when patients with hearsay experience of root canal therapy and oral surgery were analyzed. Former endodontic patients without oral surgery treatment experience who had heard that root canal therapy was the most unpleasant dental procedure recorded lower anxiety levels (2.4) (Table 5) than did patients who had not heard root canal therapy to be the most unpleasant (3.2) (Table 4). Also, former oral surgery patients with no root canal therapy experience but with hearsay experience showed anxiety levels (2.8) (Table 5) similar to, but not lower than, patients with no hearsay experience (3.2) (Table 4). These findings suggest that in endodontics, and to a lesser extent oral surgery, experience may counteract the negative influence of hearsay on the anxiety level of patients. It also corroborates the study of LeClaire et al. (8), who found that 44% of patients having root canal therapy showed a decrease in fearfulness. The Clinician's Role
The clinician must first identify the apprehensive patient. This can be done simply by asking the patient "How anxious do you become when you have dental work?" (1) or "Are you anxious about having root canal therapy?" Insight into whether the patient is anxious can be obtained. Having identified the anxious patient, the clinician can play a major role
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465
in the reduction of anxiety by being communicative and understanding and by providing information and assurances to control and prevent discomfort (13). Although LeClaire et al. (8) found that the local anesthetic injection, sensation of files introduced, working in the canals, and tapping or pushing on a sore tooth were ranked as the most unpleasant procedural aspects of root canal therapy, the dentist's "chairside" behavior can have a significant effect on patient anxiety. Among dental phobics, 45% attributed their fear not to painful treatment but to the "rough" treatment of a past dentist (5). Rankin and Harris (3) found that good experiences seem to attenuate the impact of bad experiences. The greatest contribution a dentist can make to reducing anxiety is to provide a positive experience and train the patient in the use of effective coping skills. Coping skills that have been suggested are hypnosis, controlled breathing, relaxation, distraction, and systemic desensitization (1, 14, 15). Thus, through compassionate, painless dentistry and by providing the patient with information and coping skills, the clinician may eliminate the effects of hearsay, prevent the occurrence of unpleasant experiences, and decrease overall patient anxiety. The patient may then become a messenger to others of the positive image of root canal therapy. The authors thank the staff at Headquarters, Test and Experimentation Command, Fort Hood, TX for their statistical support and Dr. Morrison Wong for his editorial assistance. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of Defense or the United States government. Dr. Wong is chief of endodontics and mentor in the Advanced Educational Program in General Dentistry (2 yr) at Fort Hood, TX. Dr. Lytle is General Dental Officer with the 92nd Medical Detachment (Dental Service), Hanau, Federal Republic of Germany. Address requests for reprints to COL Marston Wong, USA DENTAC, Frt. Hood, TX 76544-5063.
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