TICLES

e~avio~a~ selfmanagew2en erence among orthodontic patient

E. Joseph LeCompte, Ronald G. Thomas, Frank J. Courts, an

Twenty-nine new orthodontic patients and 30 experienced orthodontic patients received either behavioral self-management of toothbrushing and mouth rinsing or an experimental regimen that consisted of prompting by the orthodontist to brush and rinse regularly plus instrucUons to turn in home care materials during orthodontic visits. Several sets of data showed uniformly high rates of brushing and rinsing among all four groups of subjects. Several data sets also showed significant improvements in oral health status among ail four groups. Substantive and methodologic directions for future research are delineated. (AM J ORTHOD DENTOFAC ORTHOP 1987;91 :I 5-21.)

ey words: Adherence, orthodontics, self-management, self-care, hygiene

he presence in the oral cavity of metal bands, brackets, arch wires, springs, and other hard- ware predisposes the orthodontic patient to enamel de- calcification, dental caries, and gingivitis. ‘J The use of products containing fluoride can prevent and reverse dramatically the process of decalcification because flu- oride reduces bacterial acid production, enhances re- mineralization, and is sometimes incorporated into tooth ecamel. 1.4 Daily self-applications of products con- taining low concentrations of fluoride are the best means to prevent disease in a person with a mature dentition.5.6 Because most orthodontic patients have mature teeth, the orthodontist’s goal is to promote daily use of den- tifrices and rinses containing fluoride.

Traditionally, dentists have attempted to promote their patients’ home care activities with instruction and persuasion. The orthodox approaches succeeded in get- ting people to learn facts and concepts,7.8 but they failed to affect the rates with which people perform home care behaviors as snch.y.‘o Traditionally, behavioral psy- chologists have attempted to increase rates of motor activities through the use of short-term rewards contin- gent upon targeted performances (for example, Ayllon and Azrin”). Contingency management for oral hy- giene performances has succeeded in influencing the rates with which such performances occur.‘2.‘3

One approach to programming home care contin- gencies that is potentially beneficial involves training people to reward themselves for completing targeted adherence performances. “Behavioral self-manage-

From the University of Florida

ment training” entails consistent activities for “self- monitoring, ” “goal setting, ” “self-evaluation,” and “self-reward.“‘4-‘6 Because the activities of mouth rins- ing and toothbrushing are critical from the vantage point of the orthodontist, behavioral self-management for orthodontic patients should entail consistent activities for self-monitoring of rinsing and brushing, exact rins- ing and brushing goals, exact definitions of goal at- tainment for rinsing and brushing, and exact instruc- tions for self-reward contingent upon achieving rinsing and/or brushing performance criteria.

Reported here is an evaluation of the effects of a behavioral self-management program that incorporated all of the previously mentioned features. Previewed briefly, an orthodontist provided each of 15 relatively new patients with a packet containing a carefully pre- pared manual for self-management of rinsing and bmsh- ing along with all of the materials necessary to under- take an &-week self-management program. The ortho- dontist provided each of 16 other relatively new patients with instructions on how to rinse and brush properly, with the materials to do so for 8 weeks, with instructions to return the materials at each office visit, and with an impromptu persuasive speech on the importance of oral hygiene activities during orthodontic therapy. Pn addi- tion, two groups of 14 experienced orthodontic patients (that is, patients who had been wearing appliances for 1 to 2 years) also received one of these regimens. The oral health status of all 59 patients was variousPy as- sessed at regular intervals throughout 8 weeks of ortho- dontic treatment and the oral health of half of the pa- tients was assessed at a “follow-up” of short duration. In addition, relatively unobtrusive assessment of com-

pliance pith the self-management regimen was under- taken.

The subjects comprised 59 patients selected from the Graduate Orthodontic Program at the University of Florida College of Dentistry. Criteria for inclusion were receipt of full-banded orthodontic therapy and an ab- sence of handicapping medical conditions. Subjects were between 12 and 3 1 years of age, x = 16.3 years. Thirty-one subjects had been wearing appliances for 1 to 6 months, ?I = 3.2 months; they were designated as ‘“new” orthodontic patients. Twenty-eight had been wearing appliances for 1 to 2 years, x = 1.6 years; they were designated as “experienced” orthodontic pa- tients. As participants in the Graduate Orthodontic Pro- gram, all 59 subjects had been thoroughly instructed in tootbb~shing and mouth rinsing techniques and had demonstrated proficiency in these activities. These ini- tial instructional techniques and proficiency-assessment methods are a matter of routine in the college. They amount to performance skill training for brushing and rinsing and are devoid of formal content vis-a-vis the adherence issue. Three potential subjects withdrew from the experiment for reasons unrelated to their con- dition assignment.

One of two experimenters actually working with the patients was an orthodontic resident (E.J.L.) who per- formed the orthodontic therapy and carried out the be- havioral self-management versus “instruction-plus-per- suasion” manipulation. The other was a pedodontist and immunologist (F.J.C.) who, without knowledge of the subject’s experimental assignment, carried out the various oral health assessments.

Each of the 29 subjects in the behavioral self-man- agement condition received a packet containing an un- published self-management manualI and the neces- sary materials to maintain behavior records and to rinse and brush twice daily for 10 weeks. The materials in- cluded (a) a set of adhesive strips bearing typed instruc- tions prompting their use for mirror-mounting the charts, (b) two newly sharpened pencils, (c) three tubes of fluoridated toothpaste that were premeasured in grams of weight, (d) two toothbrushes, (e) three bottles of fluoride mouth rinse that were premeasured in mil- liliters of volume, and (f) a measuring cap.

The manual began with illustrated instructions on toothb~~hing and fluoride mouth rinsing. It then over- viewed the steps in self-management of behavior as involving self-monitoring, goal-setting, self-evalu-

ation, and self-reward. The remainder of the manual contained detailed instructions on the patient’s IO-week self-management project.

The manual called for posting behavior recording charts on a bathroom mirror. It cahed for (baseline) self-monitoring of brushing and rinsing for 2 weeks and for self-managing both behaviors for 8 subsequent weeks. The manual established daily and weekly goals for brushing and rinsing and it prompted positive self- evaluation immediately after daily and weekly goal at- tainment. The manual called for daily and weekly self- reward contingent upon goal attainment and it provided a sample “menu” of potentially rewarding objects and activities. At the end of the manual, there were three easily detachable pages of recording charts.

Each of the 30 subjects in the “bisections-plus- persuasion” condition received a packet containing the first four pages of the self-management manual- namely, those pages describing the mech~ic~ of brush- ing and rinsing. These packets also contained three premeasured tubes of toothpaste with fluoride, two toothbrushes, three premeasured bottles of fluoride mouth rinse, and a measuring cap.

In addition to the above materials and those required for full-band orthodontic therapy, some materials were necessary to conduct the evaluations of each patient’s oral health status at various points during the project. These included 500 mL of MSB agar, 100 (50 mL) culture dishes, and one anaerobic culture vessel.

Procedure

The study involved four sets of activities: (a) initial assessment and assignment of subjects to conditions, (b) implementation of one or the other experimental regimen, (c) periodic acquisition of compliance and oral health data, and (d) short-duration follow-up.

Initial assessment and condition assignment. Sev- enty patients who met the two criteria specified were told during one of their orthodontic visits that an ex- periment on oral hygiene was being undertaken and that they could participate if they wished. Each was then supplied with a complete informed consent document to take home, read, and return. Fifty-nine of the 70 patients returned the signed consent document: were selected as subjects, and were evaluated by quantitative indices (described later) of gingival inflammation, tooth plaque coverage, and cariogenic bacterial activity. Each subject’s teeth were then debrided so as to be as clean as possible, given that orthodontic bands were in place. Finally, each of the 59 subjects was classified as a new or experienced orthodontic patient and was assigned to the behavioral self-management (SM) group or to the instructions-plus-persuasion (IP) group on the basis of

Oral hygiene adkerence 17

arrival order. There were no significant age or education differences among the four groups.

Behavioral self-management versus instructions- plus-persuasion. The orthodontist introduced the be- havioral self-management (SM) program to each subject at the end of the assessment and condition-assignment activities. For the 29 subjects (15 new and 14 experi- enced patients) in the, SM condition, this involved hand- ing the packet to the patient, stressing the importance of following the manual’s directions exactly, explaining basic self-management principles, describing the steps in the project, and stressing the importance of careful self-reward. A.fter explaining the program, the ortho- dontist scheduled appointments 2, 5, and 8 weeks in advance. He also reminded the patient to bring in the behavior recording charts, mouth rinse bottles, and toothpaste tubes at each appointment. (The manual also instructed the patient to return these materials at each visit.)

At each of the three subsequent visits to the office, the orthodontist performed routine adjustments, col- lected the various residual products of self-management activities, and stored them out of view. During the visit 2 weeks later, the orthodontist assisted the patient in calculating his/her weekly rinsing and brushing goals for the duration of the project. During the visit 8 weeks later, the o~hodontist solicited the patient’s participa- tion in a follow-up evaluation in 2 or 3 months. He also provided additional recording forms and adhesive tapes, and encouraged the patient to purchase his/her own supply of toothbrushes and other home care materials. After the orthodontic and behavioral work was finished at each of the three office visits, the pedodontist/im- munologist arrived and undertook the various oral health assessments.

The orthodontist also introduced the instructions- plus-persuasion (IP) program to each subject at the end of the assessment and condition-assignment activities. For these 30 subjects (15 new and 15 experienced pa- tients), this involved handing the packet to the patient, delivering a 2-minute persuasive speech on the impor- tance of good oral hygiene, and instructing the patient to return all mouth rinse bottles and tubes of toothpaste at each successive office visit. The orthodontist then scheduled appointments 2, 5, and 8 weeks hence and reminded the patient to return the mouth rinse bottles and toothpaste tubes at each remaining appointment.

During the three subsequent visits, the orthodontist performed routine adjustments, collected empty tubes and bottles, and stored them out of view. During the visit 8 weeks later, the orthodontist solicited the pa- tient’s participation in a follow-up evaluation and en- couraged the patient to purchase his or her own supply

of home care materials as soon as possible. After each visit, the pedodontist/immunologist performed the var- ious oral health assessments.

Acquisition of compliance and oral health data. ill each office visit for the next several weeks, the 29 subjects in the SM condition and the 30 subjects in the IP condition provided measures of compliance with their respective experimental regimens. For all 59 sub- jects, these included measures of toothpaste (in grams) and of mouth rinse (in milliliters) before and after each item was taken home. For the 29 subjects in the S condition, these also included chart reports of daily rinsing and brushing.

At each office visit, all 59 subjects also provided three measures of oral health status. Gingival inflam- mation was quantified with a modification of the Gin- gival Index (GI) of Lee and Silness.” This index sam- ples the soft tissue along the mesial, distal, buccal, and lingual surfaces of four representative teeth. It uses a four-point scale wherein “0” represents normal gingiva and “3” represents marked redness and edema, ulcer- ation, and spontaneous bleeding. Plaque coverage at the dentogingival junction was assessed with the Plaque Index (PlI) of Silness and L6e.19 This index measures the thickness of plaque deposits using the same surfaces and the same 0 to 3 scale used in the GI. In this four- point scale, “0” represents no plaque in the gingival area and “3” represents abundant soft matter within the gingival pocket and/or on the margin and adjacent tooth surfaces.

These two indices can be used reliably by well- trained assessors. ‘x.19 Only one well-trained assessor was available for this study. Hence, interrater reliability within the project was not measurable. The single as- sessor was kept uninformed about subjects’ experi- mental condition assignments.

Cariogenic bacterial activity was quantified using the technique described by Gold, Jordan, and Van Houte.2o At each visit each patient was instructed to expectorate 2 to 4 mL of saliva into a small vial. Sam- ples were transferred to the convex surface of MSB agar after serial dilutions made in 0.05% yeast extract water. The agar plates were incubated within 6 hours in 95% N, and 5% CO,. After 48 hours the colonies on a predetermined agar plate were counted and a mean value was determined representmg colony forming units per milliliter of saliva. The technique of Gold, Jordan, and Van Haute” is specific for isolating the bacterium Streptococcus mutans, the most frequently ir~p~icated bacterium in the etiology of dental caries. z” In addition, some evidence exists that fluoride products have a spe- cific action on this bacterium (for example, Mayhew and Brown, 1981,” Yost and VanDemark, 197&*‘).

le I, Means and standard deviations showing baseline and percentage change from baseline PI1 and 61 scores for each group at each assessment

Plaque Index scores Self-management

New patients Experienced patients

Instructions-persuasion New patients Experienced patients

Gin,:ival Index scores

Self-management New patients Experienced patients

Tnstructicns-persuasion New patients Experienced patients

15 1.61 (0.58) -29.6 (32.3) -42.7 (31.0) -50.5 (26.9) 14 1.42 (0.36) -21.7 (23.0) -34.8 (21.0) -32.0 (22.0)

16 1.19 (0.65) -22.6 (35.7) -21.0 (44.8) -32.6 (39.6) 14 1.06 (0.68) - IS.9 (42.4) -32.8 (32.5) -32.5 (34.3)

15 1.57 (0.50) - 19.0 (14.8) -42.1 (27.0) -43.1 (26.4) 14 1.58 (0.49) - 19.8 (18.7) -40.3 (18.0) -40.8 (22.4)

16 1.21 (0.65) - 12.5 (17.8) - 18.7 (37.0) - 26.3 (47.1) 14 1.19 (0.56) -35.2 (24.0) -43.9 (34.3) -45.8 (35.3)

Self-management New patients Experienced patients

Instructions-persuasion New patients Experienced patients

15 1.2 x lo6 (1.2 x 106) 79.6 (439.6) -59.5 (74.4) -95.0 (8.1) 14 2.8 x lo6 (5.1 x 10y 210.5 (715.5) -83.2 (35.3) -94.4 (7.2)

16 9.9 x lO'(1.3 x 106) -21.7 (135.9) -84.4 (12.1) - 96.1 (3.0) 14 6.4 x 10’ (9.6 x 105) 229.6 (690.1) -47.2 (82.1) - 68.7 (59.1)

NOTE: The equal mean and standard deviation for the new self-management patient’s baseline are a result of rounding off and is not a misprint.

FoEiow-ug. At the end of the 8-week experimental period, subjects in both conditions were requested to participate in a subsequent oral health assessment 2 or 3 months later. When these “follow-up” assessments occurred 3 months later on the average, the GI and HI scores were obtained one final time. Seventeen subjects from the experienced groups of patients were out of their appliances by the time follow-up occurred. There- fore, experienced subjects were not included in follow- up analyses.

naiysls model and method

In general the data were evaluated by separate groups X occasions, unweighted means analyses of variance, with either two or four groups and with three repeated occasions (see Winer, 196223). In some in- stances baseline-referenced change scores were used. Data from the brief duration follow-up were evaluated

separately. The actual calculations were one using software from the Statistical Analysis System’4 and an IBM 3033 computer terminal” that accessed the state of Florida’s Northeast Regional Data Center.

Rinsing and brushing rep

Each of the 15 new and I4 experienced patients in the SM condition turned in chti reports of daily brush- ing and rinsing during orthodontic appointments at the 2nd, 5th, and 8th weeks of the project. For each subject the reported totals for each behavior were transformed into three single averages representing the weekly per- formance frequencies during the 2- or 3-week intervd before each of the three orthodontic a~~~i~tme~ts. For both rinsing and brushing reports, the three weekly average values for the 15 new patients were compared with those of the 14 experienced patients using a 2 x 3

“IBM Corporation, Danbury, Corm

Oral hygiene adherence d

(groups x occasions) analysis of variance. Neither the analysis for reported rinsing averages nor the analysis for reported brushing averages yielded a significant in- teraction or significant main effects for group or oc- casion. Fourteen rinsings and 14 brushings per week constituted perfect adherence to the self-management program. Twelve rinsings and 12.7 brushings per week were reported on the average. These data point to a high degree of chart-recorded adherence among both new and experienced patients.

Q~J~~ rhse and toothpaste

Each of the 59 subjects was given dispenser caps that provided for a volume of 7.5 mL of rinse to be used at each rinsing. When the measured containers were returned at the 2-, 5-, and g-week orthodontic appointments, each subject’s volume of rinse remaining was again measured in milliliters and was subtracted from the previously measured values so as to quantify the volume of mouth rinse used by that subject during the interval before the visit. The volume missing was then divided by two or three and the resulting weekly average volumes of rinse used between visits were an- alyzed with a 4 X 3 (groups X occasions) analysis of variance. The analysis yielded no significant main ef- fects or interactions. Perfect adherence to the twice daily mouth rinsing regimen would require 105 mL per week. On the average, 104 mL per week was used during this experiment.

Each of the 59 subjects was instructed to cover the l-inch surface of the toothbrush evenly with toothpaste at each brushing. When the measured tubes were re- turned at the 2-, 5, and S-week appointments, each was weighed so as to quantify the weight of toothpaste used by each subject during the interval before the visit. Each subject’s weight of toothpaste used was then treated and analyzed as was the unreturned mouth rinse value. The analysis yielded no significant main effects or interactions. The prescribed covering of toothpaste squeezed evenly weighs approximately 1 g. Hence 14 g/weekly approximates perfect adherence to the brush- ing regimen. On the average, 15.4 g weekly was used during the experiment.

ue ~~v~~~g~, gingival inflammation, and erial ealany counts

Plaque scores (PlI), gingival inflammation scores (GI), and bacterial colony counts were obtained at the first project-related (baseline) orthodontic visit and during each of the three subsequent visits. The three data sets were evaluated with separate 4 x 3 (groups x occasions) analyses of variance in which the PII, GI, and bacterial colony scores were expressed as

80

60

i 60 w n.

80

UJEEKS

Fig. 1. Mean percentage change from baseline for PII, GI, and S. mutans for all subjects at each occasion,

percentages of baseline values (summarized in Tables I and II).

For PI1 scores the analysis yielded a significant main effect for occasions: F (2,104) = 4.67; P = 0.0114, with nonsignificant effects for groups and for the in- teraction. Subsequent Duncan’s multiple range tests at the 0.05 level showed the change between week 0 (base- line) and week 2 to be significantly less than the changes between week 0 and weeks 5 and 8 (see the upper section of Table I). For GI scores the analysis also yielded a significant main effect for occasions: F (2,106) = 11.76; P = 0.0001, with nonsignificant ef- fects for groups and for the interaction. Again, can’s tests at the 0.05 level showed the change between week 0 and week 2 to be significantly less than the changes between week 0 and weeks 5 and 8 (see the lower section of Table I). For bacterial colony counts, the analysis again yielded a significant main effect for occasions: F (2,57) = 6.16; P = 0.0033, with non- significant remaining effects. Again, Duncan’s tests at the 0.05 level showed the change between week 0 and week 2 to be significantly different from the changes between week 0 and weeks 5 and E (see Table II).

The data that produced the three significant effects

McClynn et al.

for occaisions are summarized graphically in Fig. 1, in which all subjects’ PlI, GI, and S. mutuns scores are expressed as mean percentage change from baseline values. In general, the oral health of subjects in all four groups improved despite the presence of orthodontic appliances. As can be seen in Fig. 1, the bacterial colony counts increased between week 0 and week 2. This finding cannot be explained confidently, nor can the apparent discordance between bacterial colony scores and the PlI and GI values recorded at the week 2 assessment.

The various results can be summarized as follows. The behavior recording charts that subjects returned pointed to stable and high rates of both brushing and mouth rinsing among subjects in the two SM groups. The measures of unused toothpaste and mouth rinse that subjects returned pointed to targeted amounts of material used in all four groups, hence corroborating the behavioral reports. Finally, assessments of tooth plaque, gingival inflammation, and salivary S. mutans mirrored steadily improving oral hygiene in all four groups, corroborating both the charted behavior and material-used measures.

As noted, 17 of the experienced patients were out of th.eir appliances when the 3-month follow-up oc- curred. Hence, only data from the new patients were analyzed. The plaque scores for both the SM and IP subjects were low and nondifferent: t (30) = 0.96. This was true also for gingival inflammation scores: t(30) = 1.77. Bacterial colony counts were not ob- tained .

The four groups of subjects reported high rates of prescribed home care behaviors and the reports were corroborated by data in the form of residual home care products. The oral health status of all four groups im- proved significantly in concert with the increased rates of home care activities. The improvement was main- tained 5 months after the program was begun, even though orthodontic appliances were in place. These re- sults prompt continued research and suggest some di- rections it might take.

Improvement among subjects exposed to the IP pro- tocol constitutes the most important finding. Orthodon- tists could make meaningful use of the knowledge that adherence to rinsing and brushing regimens can be en- hanced by merely providing patients with home care products and instructing them to bring them along to each orthodontic visit. The results for the present IP protocol point to such a possibility. An experiment is

Am. J. Qrfhod. Dentofac. Orthop. January 1987

needed in which the present IP protocol is compared with a regimen that more nearly approximates the normative behavior of o~hodo~tists-~arnely~ one in which home care materials are neither provided nor returned.

Improvement among subjects exposed to the S protocol was not surprising. Behavioral self-manage- ment training is a bona fide part of the behavior therapist’s armamentarium and the specific package used here was empirically developed in related work (McGlynn and associates, 198525). Again, however, re- search is needed to compare the SM protocol with the normative behavior of orthodontists.

The methods described here could be adapted to future research urith little modification. I-Iaving two judges experienced with the PII and GI scales and es- tablishing reliability between them would be a signif- icant improvement. In addition, several other measures of cariogenic bacterial action26 could be incorporated into future experiments. Finally, a follow-up of longer duration would be called for in the event that the II? protocol or the SM protocol produced improvements beyond those associated with routine o~l~odontic man- agement

This research was supported in part by grant no. 5 TX?. DE 07133-03 from the National Institute of Dental Research.

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Reprint requests to: F. Dudley McGlynn Department of Community Dentistry, Box J-404 J. Hillis Miller Health Center College of Dentistry University of Florida Gainesville, FL 32610