ABSTRACT
Objective
The study aimed to test the efficacy of an online cognitive‐behavioural therapy dental anxiety intervention (o‐CBT) that could be easily implemented in dental healthcare settings.
Methods
An online cognitive‐behavioural protocol based on psychoeducation, exposure to feared dental procedures and cognitive restructuring was developed. A randomised controlled trial was conducted (N = 499) to test its efficacy. Consenting adult dental patients (18–75 years old) who met inclusion criteria (e.g., high dental anxiety) were randomised to one of three arms, (a) intervention assisted by psychology staff (PI) (n = 162), (b) intervention assisted by dental staff (DI) (n = 167), or (c) a control condition (C) (n = 170). Primary outcome measures were the Modified Dental Anxiety Scale (MDAS) and the Anxiety and Related Disorders Interview Schedule DSM‐V (ADIS) rating of fear. Generalised linear models for repeated measures based on intention to treat analyses were used to compare the three groups on dental anxiety, fear, avoidance and overall severity of dental phobia.
Results
Dental anxiety was significantly lower in both PI and DI groups when compared to the control condition. Interestingly, reductions in dental anxiety favoured the DI group at 6 (p = 0.008) and 12 months only (p = 0.009). Overall, equivalency was observed between the two intervention groups (PI and DI), as there were no significant differences in dental anxiety when the dental arm was compared to the psychology arm across all time points (p > 0.05).
Conclusion
The online cognitive‐behavioural intervention was efficacious in reducing dental anxiety when compared to a control condition in an urban sample of patients receiving treatment in a dental school setting. Examination of its effectiveness when administered in dental offices under less controlled conditions is warranted.
Trial Registration: NCT03680755
Keywords: cognitive behavioural therapy, dental anxiety, randomised controlled trial
1. Introduction
Dental anxiety is a prevalent condition that can result in oral health impairment and reduced quality of life, affecting 10%–20% of adults in the United States [1, 2, 3], 21.4% in a recent study in Australia [4], and a lower percentage in recent European studies (Norway 9.2% and Finland 6%, respectively) [5, 6, 7]. Dental anxiety refers to the fear of dental procedures a patient experiences either before or during their appointment. Dental phobia, on the other hand, is a more acute form of dental anxiety that causes patients to delay or cancel at least some of their dental appointments. Psychological interventions based on a cognitive behavioural approach represent the gold standard for anxiety management. Cognitive‐behavioural therapy (CBT) is a highly effective treatment method for anxiety disorders including dental anxiety. A previous meta‐analysis [8] provided support for CBT efficacy in reducing dental anxiety among adults, even when administered in a limited number of sessions [9, 10, 11, 12, 13].
CBT is typically administered in 8–12 weekly sessions by a licensed provider (e.g., clinical psychology, licensed social worker). This format is both time‐consuming and costly, particularly for individuals without health insurance. Furthermore, trained mental health providers are not typically co‐located in dental settings. To meet the needs of patients, the ideal approach would include brief CBT interventions that can be delivered by dental staff. Prior research supports brief CBT for reducing dental anxiety [14] including a study by Spindler and colleagues that demonstrated that a brief cognitive‐behavioural intervention performed by dentists may help patients overcome their fear and attend dental treatments more regularly [15].
Many dentists report not receiving CBT training [16] or not utilising psychological techniques for dental anxiety management due to lack of confidence in their ability [17]. That, coupled with issues related to accessibility to CBT providers, may lead dentists to opt for pharmacological treatments (e.g., sedation), which are costlier and may place patients at additional risk [18]. An overreliance on pharmacological management of dental anxiety may inadvertently perpetuate dental anxiety, as it facilitates the avoidance of feared situations and reinforces the beliefs that dental procedures should be feared [19]. Establishing a reliable nonpharmacological method to reduce dental anxiety in the dental office could be an efficient first‐line treatment. Early intervention may reduce the cycle of fear and avoidance, in which patients who experience distress when thinking about dental care tend to avoid (i.e., cancel or no‐show) more of their appointments [20].
In response to the need for a brief treatment with more feasible dissemination in the dental setting, an online CBT (o‐CBT) dental anxiety treatment program was developed through a research collaboration between Kornberg School of Dentistry and the Department of Psychology at Temple University. The intervention was initially developed by dental and clinical psychology faculty supported by funding from the Pennsylvania Department of Health, and later pilot tested with funding from the National Institutes of Health [3]. The intervention involves a single 1‐h online session delivered with the aid of either psychology personnel or dental staff present in the room to assist patients with navigating through the program and completing more challenging tasks (e.g., cognitive restructuring), as needed. An earlier randomised controlled trial found significantly reduced dental anxiety compared to a non‐intervention group [3]. Prior pilot testing involving the o‐CBT program also supported the feasibility and acceptability as delivered by dental staff, as well as psychology personnel with more specialised CBT training [21, 22]. Ten patients with dental anxiety who received the o‐CBT program rated the feasibility and acceptability to be adequate as all patients completed the intervention, eight of 10 reported being mostly or very satisfied with the intervention, and patients gave high ratings to the following four questions: how helpful they found the intervention, how easy it was to understand, how much the dental anxiety intervention helped them get through their dental care appointment, and how likely they were to schedule a checkup within the next year [22].
Building upon the formative research, the present study aimed to compare the effect of two different interventionist types: (a) psychology personnel with graduate‐level training and experience in CBT (e.g., psychologists, postdoctoral fellows) and (b) dental staff with brief but specific training in the administration of the CBT intervention (e.g., dental assistants). Secondly, it aimed to compare the reduction in dental anxiety in the o‐CBT intervention groups (i.e., psychology personnel or dental staff) to a time‐ and attention‐matched control condition. It was hypothesised that the psychology and dental staff arms would be comparable at reducing dental anxiety (i.e., equivalency) and that both o‐CBT groups would outperform the control condition (i.e., superiority).
2. Materials and Methods
2.1. Design
This was a single‐center parallel study with randomisation to either a psychology intervention (PI) group, a dental intervention (DI) group, or a control (C) group (allocation ratio: 1:1:1). Participants in PI and DI received o‐CBT immediately preceding their scheduled dental appointment. Control participants similarly viewed a 1‐h nature video prior to attending their scheduled dental appointment. The study was registered at ClinicalTrials.gov (NCT03680755) and CONSORT guidelines were used to develop this manuscript (Table A1).
2.2. Sample Selection
Power calculations considered a change of two points in the Modified Dental Anxiety Scale (MDAS) score as the equivalence limit difference between the two intervention conditions. Based on a two‐group t‐test of equivalence in means between the two intervention conditions, with a power of 86% and a one‐sided alpha level of 0.025, an estimated 120 subjects per condition (N = 240) were required for the equivalence hypothesis test. The estimation conservatively allowed for an attrition rate as high as 20%. This attrition allowance increased the required sample size to 550 subjects, i.e., 183 in each of three conditions including the control.
Recruitment was carried out through the clinics at Temple University Kornberg School of Dentistry (TUKSoD) between 2019 and 2023. All new patients were identified through the scheduling software and invited to participate through telephone outreach before their dental appointment if they met screening criteria. There were no restrictions on enrollment in terms of gender, economic status, or ethnic group.
To be eligible, patients had to be between 18 and 75 years of age, fluent in spoken and written English, have scheduled a dental treatment appointment, be willing and able to give informed consent, participate responsibly in the study protocol, meet criteria for high dental anxiety based on the MDAS, and endorse at least some oral‐health‐related impairment at the administration of a semi‐structured diagnostic interview. Participants received up to a total of $175 in Amazon and/or Walmart gift cards for completion of all study visits. Seventy‐five dollars was provided at their intervention visit, followed by two additional payments of $50 each at the 1‐ and 3‐month follow‐ups.
Given the higher than anticipated number of participants who did not attend their dental appointment after consenting verbally over the phone to participate in this study, we extended our recruitment target (after IRB and study sponsor permission) and continued recruitment until we reached a final sample size of 503 participants. Recruitment was stopped when enrollment targets were reached. The study was approved by the IRB at Temple University (Protocol #24466). All patients additionally provided signed informed consent when they presented for the study visit.
2.3. Procedure
Participation in the study involved completing self‐report questionnaires online or, for individuals without internet access or email, by telephone, and for all participants a telephone diagnostic interview. An investigator administered the randomisation of participants (computer generated) and the study coordinator distributed the appointments. The randomisation file was secured and restricted to the time of randomisation so that staff would not know to what arm the patient had been randomised until an hour before the intervention visit. Randomisation was assigned immediately following baseline assessments for the entire sample.
For practical and ethical reasons related to the fact that participants were paying for the dental treatment themselves and the immediacy of the intervention group to which they were allocated, we could not blind them to the outcome of the randomisation. After randomisation, each participant was instructed to complete the self‐report assessments and the diagnostic interview before coming in for their dental appointment. Participants in all groups were asked to come in 2 h before their dental appointment to complete o‐CBT or watch a nature video, depending on their randomisation group. Following their dental appointment, participants completed a brief post‐appointment debrief questionnaire. One month after the dental appointment, participants were contacted by phone and asked to complete follow‐up assessments. If a participant did not respond to study staff's initial contact attempt, research assistants continued to call that participant weekly for 1 month. Participants who never responded to requests for two consecutive follow‐up assessments were considered lost to follow‐up. Follow‐ups were repeated at 3, 6 and 12 months. Harm events such as severe anxiety associated with stoppage of the intervention or the immediate need for further intervention and cancellation of following dental appointment were noted and compared across arms of the study yearly after the first 75 patients were enrolled in the study as required by the funder.
2.4. Intervention
o‐CBT consisted of a single‐session, 1‐h computerised intervention that assisted the participant in building coping skills for managing dental anxiety. Participants completed o‐CBT in a research office on a desktop computer. Headphones were available as needed. A therapy aid oriented the participant to the online intervention and was available to answer any questions and to assist participants with any difficulty. The therapy aid was either psychology personnel (graduate‐level psychology staff trained in CBT) or a dental assistant (minimally trained in CBT).
The o‐CBT intervention began with a psychoeducation module, which provided participants with basic education about the nature of dental anxiety. Next, patients were guided through a brief motivational interviewing exercise that helped them consider the benefits and drawbacks of working on their dental anxiety. Thereafter, patients were guided through exposure exercises, which included opportunities to practise coping with their dental anxiety. For the exposure exercises, patients were first asked to select their three most feared dental procedures from a list of six procedures: drilling and having a cavity filled, cleaning, anaesthetic injection, root canal, oral X‐ray and tooth extraction. Participants created a fear hierarchy by ranking these procedures from least to most anxiety‐provoking. Patients then watched video recordings of their top three feared procedures, starting with the least anxiety‐provoking and progressing to the most anxiety‐provoking.
The exposure paradigm included three levels of fear‐inducing scenarios for each of the three selected procedures: (1) The first video provided a basic explanation of the selected procedure. Animations of aspects of the procedure that occur within the mouth were included, as were close‐ups of the dental tools employed. (2) The second video depicted a dentist and/or hygienist conducting the procedure with a patient. This video was coupled with a voiceover providing basic training on the use of cognitive coping skills for dental anxiety throughout. The voiceover was a ‘dialogue’ between the narrator, who demonstrated how to effectively cope with anxious thoughts, and the patient, who was led through the steps to develop coping thoughts. The third video was filmed from the perspective of the patient in the dental chair and provided more intensive exposure to the feared dental procedure. The participant watching the intervention was instructed to think of their own coping thoughts based on the information provided in the preceding videos. In total, participants viewed nine exposure videos in the fear hierarchy. The intervention closed with a brief module providing additional motivational enhancement for attending future dental appointments.
2.5. Training in CBT
All interventionists (or ‘therapy aids’) received a 2‐h training session on dental anxiety/phobia, CBT principles, consenting participants, intervention and control conditions, administration of the intervention, post‐intervention and post‐appointment debriefing, the payment process and post‐appointment procedures. The training was conducted by a senior investigator. Therapy aids were provided an ‘Intervention Day’ checklist and a brief overview document. After scoring a minimum of 90% on a knowledge assessment reviewing their understanding of these documents, the therapy aid then conducted preliminary walk‐throughs with the senior investigator acting as an intervention participant, then a control participant. Lastly, therapy aids were required to complete a final mock‐intervention visit before being able to see participants independently.
2.6. Outcomes
2.6.1. Primary Outcome: Dental Anxiety
Dental anxiety was measured using the Modified Dental Anxiety Scale (MDAS), a 5‐item self‐report measure that assesses fear of dental procedures, including drilling, scaling and polishing (i.e., cleaning), and local anaesthetic injections [23]. Items are rated on a 5‐point Likert‐type scale ranging from one (not anxious) to five (extremely anxious). The MDAS has demonstrated good internal consistency (α = 0.89) and test–retest reliability (r = 0.82, interval unspecified) [23]. In the present study, we considered patients who scored ≥ 19 on the MDAS at baseline or endorsed at least two MDAS items>four to have high dental anxiety.
2.6.2. Secondary Outcomes: Semi‐Structured Diagnostic Interview
The Anxiety Disorders Interview Schedule for DSM‐V (ADIS‐V) [24] is a semi‐structured diagnostic interview for assessing DSM‐V criteria for current anxiety, depressive, somatoform and substance use disorders [24]. The ADIS‐V has demonstrated good to excellent inter‐rater reliability for the diagnosis of all assessed disorders (к = 0.56–0.81) [24]. All diagnosticians were advanced doctoral students or research assistants who were trained to strict reliability standards established by Brown et al. [25].
2.7. Dental Phobia
Interviewers assessed participants' distress and avoidance of dental procedures on scales that ranged from 0 (none) to 8 (very severe) part of the specific phobia module of the ADIS‐V. At the conclusion of the semi‐structured interview, interviewers assigned the participant a Clinical Severity Rating (CSR) based on their level of reported fear and impairment, ranging from 0 (none) to 8 (very severe); a CSR>four indicated that the participant met criteria for diagnosis of dental phobia.
2.8. Dental Treatment Provided Post‐Intervention
The current dental terminology codes (CDT), which are a standardised set of codes used by dentists in the US to accurately document dental procedures performed on a patient, ensuring consistency when submitting insurance claims, were obtained for all the patients who underwent the intervention. CDT codes were grouped by dental practice domain (e.g., diagnostic, preventive, restorative, others, etc.) and frequency distributions explored by condition.
2.9. Attendance Pre‐ and Post‐Intervention
Mean number of appointments attended, cancelled and missed 12 months before the intervention and 12 months after the delivery of the intervention were calculated and differences explored by condition. In addition, a mean completion rate pre and post was also generated by dividing the number of appointments completed by the sum of appointments completed, no show and cancelled multiplied by 100.
2.10. Statistical Analyses
Differences between the groups on baseline socio‐demographic, clinical and psychological measures were examined using χ 2 (Pearson) or Student's t‐tests, as appropriate. Moreover, differences on the variables listed above among completers and drop‐outs were also explored. Both per protocol and intention to treat (ITT) analyses were then conducted, but only ITT analyses are reported in the results section.
To address the aims, linear mixed‐effects models for repeated measures were used to assess differences between intervention groups using the MDAS and CSR rating as continuous outcome variables, and to investigate the treatment effect on dental anxiety or phobia after accounting for other confounding factors. Statistical significance was set at p < 0.05. Multiple imputation (MI) was used to handle missing follow‐up data as described below. Data were analysed using SPSS (IBM Corporation. Released 2024. IBM SPSS Statistics for Windows, Version 29.0.2 Armonk, NY, USA).
2.11. Multiple Imputation (MI)
MI was used to handle missing follow‐up data when conducting ITT analysis for the primary objectives. The majority of missing data (79%) was due to participants cancelling their research visit and dental appointment. This was anticipated due to the nature of the intervention visit (i.e., immediately preceding the dental appointment) and the targeted recruitment of participants who met criteria for high dental anxiety, including those with avoidant behaviour. The proportion of missing data for the MDAS was as follows: 1 month (4%), 3 (6%), 6 (18.3%) and 12 months (38.6%) (Table B1). It is worth noting that participants were not compensated for 6‐ and 12‐month data collection, which likely explains the lower retention rates.
The MI procedure consisted of three steps: (1) The missing follow‐up data was filled in 100 times to generate 100 complete datasets; (2) The 100 datasets were analysed by ANCOVAs with follow‐up scores at 1, 3, 6 and 12 months as outcomes and treatment groups as the independent variable (PI vs. DI for Aim 1, or PI + DI vs. C for Aim 2), controlling for baseline scores; (3) The results from the 100 complete datasets were combined for the MI inference [26]. SAS PROC MI and PROC MIANALYZE were used for multiple imputation analysis using SAS 9.4 (SAS Institute Inc., Cary, NC, USA).
3. Results
3.1. Demographics
Of 7030 patients who received recruitment calls, 1347 expressed interest and were assessed for eligibility. A total of 503 patients were eligible, consented to participate, and were randomised to PI (n = 162), DI (n = 167) or control (n = 170) (Figure 1). Four participants were considered ‘failed to randomise’ due to errors with randomisation assignment or interventionist unavailability. These participants were notified of the error, offered the o‐CBT intervention, and were not included in data analyses.
FIGURE 1.
CONSORT flowchart.
The final sample for analyses was comprised of 499 adults (71.7% female; M age = 49, SD = 14.9) seeking dental care at the TUKSoD Clinics. The racial/ethnic composition of the sample was generally consistent with that of north Philadelphia: [27] approximately 62.4% of participants identified as Black, 26.8% identified as white/Caucasian, 4.6% identified as Asian or Pacific Islander and 6.3% identified as other. Also, 11.4% of the sample identified as Hispanic ethnicity. About 57% of the sample had a reported annual household income of less than $39 999, 33% had an income between $40 000 and $89 999, and 10% had an income equal to $90 000 or above. As noted above, no significant differences between groups on baseline demographic or clinical measures were found (see Table 1). No significant differences in mean MDAS between those who met eligibility but did not consent (19.3 ± 2.6) versus subjects who did consent (19.8 ± 3.0) were found (p = 0.16). Likewise, no differences between subjects who consented to participate and those who followed through in completing the baseline assessment and were randomised were found (19.6 ± 3.2) (p = 0.19, Table 2).
TABLE 1.
Baseline differences by condition.
| Total (N)% | Control (N)% | Dental (N)% | Psychology (N)% | Pr > |t| | |
|---|---|---|---|---|---|
| Race | |||||
| Asian | 22 (4.6) | 6 (3.6) | 8 (5.0) | 8 (5.1) | 0.49 |
| Black or African American | 301 (62.4) | 110 (66.7) | 99 (61.5) | 92 (59.0) | |
| White or Caucasian | 129 (26.8) | 39 (23.6) | 43 (26.7) | 47 (30.1) | |
| Others | 30 (6.3) | 10 (6.0) | 11 (6.8) | 9 (5.8) | |
| Ethnicity | |||||
| Hispanic or Latino | 56 (11.4) | 20 (11.8) | 15 (9.1) | 21 (13.5) | 0.46 |
| Non‐Hispanic | 434 (88.6) | 149 (88.2) | 150 (90.9) | 135 (86.5) | |
| Gender | |||||
| Female | 349 (70.6) | 125 (73.5) | 109 (66.1) | 115 (72.3) | 0.46 |
| Male | 140 (28.3) | 44 (25.9) | 53 (32.1) | 43 (27.0) | |
| Others | 5 (1.0) | 1 (0.6) | 3 (1.8) | 1 (0.6) | |
| CSR | |||||
| 0–3 | 169 (35.4) | 66 (39.5) | 54 (34.6) | 49 (31.8) | 0.34 |
| 4–8 | 308 (64.6) | 101 (60.5) | 102 (65.4) | 105 (68.2) | |
| Age (years), mean ± SD | 49.0 ± 14.9 | 48.0 ± 14.8 | 49.3 ± 14.3 | 49.7 ± 15.5 | 0.58 |
| MDAS, mean ± SD | 19.5 ± 3.6 | 19.8 ± 3.1 | 19.4 ± 3.9 | 19.4 ± 3.8 | 0.51 |
Note: Pr > |t| from chi‐square/Fisher's exact test/t‐test. p values excluded missing data.
Abbreviations: CSR, Clinical Severity Rating; M, mean; MDAS, Modified Dental Anxiety Scale; SD, standard deviation.
TABLE 2.
Mixed Model for MDAS at 1‐, 3‐, 6‐ and 12‐month follow‐ups.
| Effect | Treatment condition | Estimate | Pr > |t| |
|---|---|---|---|
| 1 month | |||
| Time × Condition | Control | Ref | |
| Dental | −0.3895 | 0.4224 | |
| Psychology | −0.9533 | 0.0500 | |
| 3 months | |||
| Time × Condition | Control | Ref | |
| Dental | −0.5655 | 0.2515 | |
| Psychology | −1.0986 | 0.0265 | |
| 6 months | |||
| Time × Condition | Control | Ref | |
| Dental | −0.9211 | 0.0733 | |
| Psychology | −1.5044 | 0.0032. | |
| 12 months | |||
| Time × Condition | Control | Ref | |
| Dental | −1.0522 | 0.0549 | |
| Psychology | −1.2711 | 0.0190 | |
Note: Pr > |t| Dental versus Psychology group from Simple Differences of time × condition least square means adjustment for multiple comparisons: 1‐month Turkey–Kramer p = 0.66, 3‐month Turkey–Kramer p = 0.70, 6‐month Turkey–Kramer p = 0.66, 12‐month Turkey–Kramer p = 0.97. Numbers in bold indicate statistical significance.
3.2. Efficacy of o‐CBT
The administration of the o‐CBT intervention was equivalent between dental and psychology staff throughout the course of the study (Simple differences of time × condition using least square means adjustments for multiple comparisons‐Turkey–Kramer at 1 month, p = 0.66, and at 12 months, p = 0.97). In addition, the o‐CBT intervention proved to be efficacious when compared to the control regardless of who administered the intervention (p > 0.05 from 3 to 12 months when evaluating pool vs. control differences).
3.2.1. Primary Outcome
The reductions of MDAS scores were of statistical significance for both the dental and the psychology arms independently and when pooled. MDAS scores changed approximately by five to six units in the score for DI and PI respectively (see Table 3) over a 12‐month period (DI from 19.4 ± 3.9 to 14.3 ± 4.6, PI from 19.4 ± 3.8 to 13.8 ± 5.1). An ANCOVA with the ITT sample (N = 499) confirmed that positive effects were seen for the reduction in MDAS for the dental arm when compared to the control over a sustained period of time (DI from 19.4 ± 3.9 to 15.0 ± 5.0, C from 19.8 ± 3.1 to 16.1 ± 4.6 at 6 months, p = 0.02). At 12 months, DI changed from 19.4 ± 3.9 to 14.3 ± 4.6, C from 19.8 ± 3.1 to 15.5 ± 4.8 p = 0.08 particularly (see Table 3).
TABLE 3.
Primary Outcome at Baseline and Follow‐ups.
| MDAS M ± SE | Control | Dental intervention | Psychology intervention | Pr > |t| |
|---|---|---|---|---|
| Baseline | 19.8 ± 3.1 | 19.4 ± 3.9 | 19.4 ± 3.8 | 0.51 |
| 1 month | 18.0 ± 4.4 | 17.2 ± 4.6 | 16.7 ± 4.7 | 0.11 |
| 3 months | 17.0 ± 4.6 | 16.1 ± 4.8 | 15.5 ± 4.9 | 0.06 |
| 6 months | 16.1 ± 4.6 | 15.0 ± 5.0 | 14.3 ± 5.1 | 0.02 |
| 12 months | 15.5 ± 4.8 | 14.3 ± 4.6 | 13.8 ± 5.1 | 0.08 |
Note: Pr > |t| from ANCOVA models from ITT analysis.
Abbreviations: M, mean; MDAS, Modified Dental Anxiety Scale; SE, standard error.
3.2.2. Secondary Outcomes
ADIS‐IV ratings of dental fear, dental avoidance and overall severity of dental phobia symptoms decreased from baseline to 12‐month follow‐up in all arms, noting positive trends. However, ANCOVAs with the ITT sample (N = 499) did not reveal significant between‐group differences on ADIS‐V after controlling for the corresponding baseline scores. The percent reduction in the number of patients meeting criteria for phobia from baseline to 3 month follow‐up was higher for the DI and C subjects (22.2%), followed by the PI intervention subjects (20.1% p = 0.40). No harms were noted.
The pre‐intervention attendance completion rate was 0.8 ± 0.2 (p = 0.79) across all study groups and 0.6 ± 0.3 (p = 0.74) post‐intervention with no significant differences by condition (Table 4). Moreover, the frequency distribution of CDT codes received by subjects after being exposed to the intervention and up to the first 3 months was as follows: (a) received only diagnostic/preventive procedures (23.2%), (b) received only restorative procedures (10%), (c) received only advanced procedures (28.2%) and (d) received a combination of procedures (38.5%). No significant differences were found in the frequency distribution of CDT codes grouped by domains from the day of delivery of the intervention until the first 3 months (p = 0.11), or after 12 months (p = 0.15) by trial condition.
TABLE 4.
Attendance outcomes pre‐ and post‐intervention.
| Apt type | Pre‐intervention M ± SE | Post‐intervention M ± SE | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Overall (n = 499) | Psychology (n = 162) | Dental (n = 167) | Control (n = 170) | p | Overall (n = 499) | Psychology (n = 162) | Dental (n = 167) | Control (n = 170) | p | |
| Apts no showed | 0.6 ± 1.1 | 0.6 ± 1.0 | 0.6 ± 1.0 | 0.7 ± 1.1 | 0.68 | 0.8 ± 1.2 | 0.8 ± 1.2 | 0.6 ± 1.1 | 0.9 ± 1.3 | 0.23 |
| Apts completed | 6.0 ± 4.9 | 6.2 ± 5.3 | 5.7 ± 4.6 | 6.2 ± 5.0 | 0.71 | 5.1 ± 5.3 | 5.4 ± 5.8 | 5.2 ± 5.3 | 4.6 ± 4.6 | 0.68 |
| Completion rate | 0.8 ± 0.2 | 0.8 ± 0.2 | 0.8 ± 0.2 | 0.8 ± 0.2 | 0.79 | 0.6 ± 0.3 | 0.6 ± 0.3 | 0.6 ± 0.3 | 0.6 ± 0.3 | 0.74 |
| Apts Cancelled | 1.3 ± 1.7 | 1.3 ± 1.9 | 1.3 ± 1.9 | 1.2 ± 1.5 | 1.00 | 1.6 ± 1.8 | 1.7 ± 1.9 | 1.6 ± 1.9 | 1.5 ± 1.6 | 0.76 |
Note: Completion rate: # of appointments completed/sum of appointments completed, no show and cancelled × 100.
Abbreviation: Apt, appointments.
4. Discussion
This study examined the effect of an online dental anxiety intervention for patients seeking dental care at a university setting. Compared with a time‐ and attention‐matched control group, the o‐CBT intervention group showed a significant reduction in dental anxiety regardless of whether the therapy aid was a dental assistant or psychology personnel as measured by a reduction from baseline to follow‐up on the MDAS. The current results build on prior work demonstrating the feasibility and acceptability of the o‐CBT for the dental anxiety programme, and suggest that dental staff (e.g., assistants, hygienists, etc.) could be trained to serve as therapy aids. The observed reductions in dental anxiety can have a meaningful impact on the oral health of adults with clinically significant dental anxiety. The CBT intervention provides coping strategies to allow patients to schedule and adhere to preventive dental appointments and would reduce avoidance of dental care and appointment interruptions (e.g., cancellations, no‐shows).
Previous studies which have trained dental personnel in CBT to manage dental anxiety showed that dental anxiety can be treated effectively by a dentist within general dental care [15, 28]. The study adds to the body of knowledge particularly when referring to low‐income urban populations in the USA, as this online intervention could support a model in which dentally anxious patients receive treatment in primary dental care by general practitioners, and when necessary, are further referred to specialised care. It is critical that dental personnel are trained in brief CBT so that they can provide this support to their patients in a regular dental setting in which highly trained CBT therapists are generally not available.
The dissemination of this intervention would also improve dental practitioner education on dental anxiety, as adequate predoctoral training in dental anxiety would mean dental students are able to: fully appreciate and recognise mental health and oral health connections; provide efficient and relevant anxiety reduction interventions for patients; modify dental treatment to include not only pharmacological but also behaviourally oriented person‐centred approaches; identify mental health problems that co‐exist with dental anxiety and are experienced by their patients and refer and collaborate with external behavioural health providers [29]. Considerations as to the accessibility of this intervention in clinic spaces will be needed, as the current set of modules is lengthy and requires a member of clinic staff to be present. However, future directions for this treatment could explore allowing the patient to view the treatment programme at home or in shorter segments.
There were some limitations to the current study. Only dental treatment‐seeking patients who initiated contact with the TUKSoD clinics were recruited into the study, thereby excluding individuals whose dental phobia may be present at greater severity and thus preventing them from accessing dental care at all. As not all potential patients had the same chance to be recruited into the study, a potential for sampling bias is possible. There was also considerable attrition from baseline assessment to the day of administration of the dental anxiety protocol, possibly due to the higher likelihood of the recruited sample to avoid their scheduled dental appointments. Still, the target recruitment was met per power analysis and found significant results, and no differences in mean MDAS collected at the screening point between those eligible and not consented vs. subjects randomised was observed. Additionally, although there was a reduction in participant ADIS scores post‐intervention, the change in scores was not significant. This may be due to the way the ADIS is scored, as participants need to report an avoidance of dental procedures due to anxiety within the last 12 months in order to score above a 3. For those with ADIS scores in the range of dental phobia, a one‐time CBT intervention may not be a sufficient treatment dose to change attendance rates, even if the level of dental anxiety is reduced. Future research should examine dose response and consider repeated administration of the exposure paradigm for patients with more severe dental anxiety or phobia. Lastly, dental attendance was not impacted post‐intervention. The o‐CBT program was a one‐time 60 min exposure and while dental anxiety is one predisposing factor for lack of attendance to dental care, there are many other enabling and needs‐related factors that play a key role in seeking care and being compliant with appointments [30] In sum, a new online tool seems to be efficacious in reducing fear of dental procedures. Examination of its effectiveness when administered in dental offices under less controlled conditions is warranted.
Conflicts of Interest
The authors declare no conflicts of interest.
Acknowledgements
We would like to thank Dr. Richard Heimberg, Emeritus Professor, for his contribution to the development of the dental anxiety management intervention and the dental and psychology students who participated throughout the conduct of this clinical trial.
Appendix A.
TABLE A1.
CONSORT 2010 checklist of information to include when reporting a randomised trial. a
| Section/Topic | Item no. | Checklist item | Reported on page no. |
|---|---|---|---|
| Title and abstract | 1a | Identification as a randomised trial in the title | 1 |
| 1b | Structured summary of trial design, methods, results, and conclusions (for specific guidance see CONSORT for abstracts) | 4 | |
| Introduction | |||
| Background and objectives | 2a | Scientific background and explanation of rationale | 6–8 |
| 2b | Specific objectives or hypotheses | 8 | |
| Methods | |||
| Trial design | 3a | Description of trial design (such as parallel, factorial) including allocation ratio | 8 |
| 3b | Important changes to methods after trial commencement (such as eligibility criteria), with reasons | 9 | |
| Participants | 4a | Eligibility criteria for participants | 9 |
| 4b | Settings and locations where the data were collected | 9 | |
| Interventions | 5 | The interventions for each group with sufficient details to allow replication, including how and when they were actually administered | 11–12 |
| Outcomes | 6a | Completely defined pre‐specified primary and secondary outcome measures, including how and when they were assessed | 13–14 |
| 6b | Any changes to trial outcomes after the trial commenced, with reasons | N/A | |
| Sample size | 7a | How sample size was determined | 8–9 |
| 7b | When applicable, explanation of any interim analyses and stopping guidelines | N/A | |
| Randomisation | |||
| Sequence generation | 8a | Method used to generate the random allocation sequence | 10 |
| 8b | Type of randomisation; details of any restriction (such as blocking and block size) | 10 | |
| Allocation concealment mechanism | 9 | Mechanism used to implement the random allocation sequence (such as sequentially numbered containers), describing any steps taken to conceal the sequence until interventions were assigned | 10 |
| Implementation | 10 | Who generated the random allocation sequence, who enrolled participants, and who assigned participants to interventions | 10 |
| Blinding | 11a | If done, who was blinded after assignment to interventions (e.g., participants, care providers, those assessing outcomes) and how | 10 |
| 11b | If relevant, description of the similarity of interventions | N/A | |
| Statistical methods | 12a | Statistical methods used to compare groups for primary and secondary outcomes | 14–15 |
| 12b | Methods for additional analyses, such as subgroup analyses and adjusted analyses | 15 | |
| Results | |||
| Participant flow (a diagram is strongly recommended) | 13a | For each group, the numbers of participants who were randomly assigned, received intended treatment, and were analysed for the primary outcome | 24 |
| 13b | For each group, losses and exclusions after randomisation, together with reasons | 24 | |
| Recruitment | 14a | Dates defining the periods of recruitment and follow‐up | 9 |
| 14b | Why the trial ended or was stopped | 9 | |
| Baseline data | 15 | A table showing baseline demographic and clinical characteristics for each group | 25 |
| Numbers analysed | 16 | For each group, number of participants (denominator) included in each analysis and whether the analysis was by original assigned groups | 14 |
| Outcomes and estimation | 17a | For each primary and secondary outcome, results for each group, and the estimated effect size and its precision (such as 95% confidence interval) | 16–18 |
| 17b | For binary outcomes, presentation of both absolute and relative effect sizes is recommended | ||
| Ancillary analyses | 18 | Results of any other analyses performed, including subgroup analyses and adjusted analyses, distinguishing pre‐specified from exploratory | 16–18 |
| Harms | 19 | All important harms or unintended effects in each group (for specific guidance see CONSORT for harms) | 17 |
| Discussion | |||
| Limitations | 20 | Trial limitations, addressing sources of potential bias, imprecision, and, if relevant, multiplicity of analyses | 19–20 |
| Generalisability | 21 | Generalisability (external validity, applicability) of the trial findings | 20 |
| Interpretation | 22 | Interpretation consistent with results, balancing benefits and harms, and considering other relevant evidence | 19–20 |
| Other information | |||
| Registration | 23 | Registration number and name of trial registry | 8 |
| Protocol | 24 | Where the full trial protocol can be accessed, if available | 8 |
| Funding | 25 | Sources of funding and other support (such as supply of drugs), role of funders | 20 |
We strongly recommend reading this statement in conjunction with the CONSORT 2010 Explanation and Elaboration for important clarifications on all the items. If relevant, we also recommend reading CONSORT extensions for cluster randomised trials, non‐inferiority and equivalence trials, non‐pharmacological treatments, herbal interventions, and pragmatic trials. Additional extensions are forthcoming: for those and for up‐to‐date references relevant to this checklist, see www.consort‐statement.org.
Source: Schulz et al. [31].
Appendix B.
TABLE B1.
Number and percentage of participants (N%) with missing data.
| N a | N in‐progress | N Missing (since last assessment) | % Missing | |
|---|---|---|---|---|
| Primary outcomes | ||||
| Time 1 (baseline) | ||||
| MDAS | 503 | 0 | 0 | 0 |
| ADIS Fear | 503 | 0 | 0 | 0 |
| Time 4 (1‐month follow‐up) | ||||
| MDAS | 349 | 0 | 14 | 4.0 |
| ADIS Fear | 349 | 0 | 14 | 4.0 |
| Time 5 (3‐month follow‐up) | ||||
| MDAS | 334 | 0 | 20 | 6.0 |
| ADIS Fear | 334 | 0 | 20 | 6.0 |
| Secondary outcomes | ||||
| Time 1 (baseline) | ||||
| Change in avoidance rating from ADIS‐5 | 503 | 0 | 0 | 0 |
| Pain Sensitivity Index | 441 | 0 | 0 | 0 |
| Distress Tolerance Scale | 441 | 0 | 0 | 0 |
| Fear Questionnaire Blood–Injection Subscale | 441 | 0 | 0 | 0 |
| Change in Distress and Interference Ratings from ADIS‐5 | 503 | 0 | 0 | 0 |
| Change in percentage of dental phobia patients from ADIS‐5 | 503 | 0 | 0 | 0 |
| Time 2 (Intervention Day) | ||||
| Pain Intensity Numeric Rating Scale | 380 | 0 | 0 | 0 |
| Time 4 (1‐month follow‐up) | ||||
| Change in Avoidance Rating from ADIS‐5 | 348 | 0 | 14 | 4.0 |
| Pain Intensity Numeric Rating Scale | 332 | 0 | 27 | 8.1 |
| Pain Sensitivity Index | 332 | 0 | 27 | 8.1 |
| Distress Tolerance Scale | 332 | 0 | 27 | 8.1 |
| Fear Questionnaire Blood–Injection Subscale | 332 | 0 | 27 | 8.1 |
| Client Satisfaction Questionnaire b | 222 | 18 | 8.1 | |
| Time 5 (3‐month follow‐up) | ||||
| Change in Avoidance Rating from ADIS‐5 | 334 | 0 | 20 | 6.0 |
| Pain Intensity Numeric Rating Scale | 328 | 0 | 27 | 8.2 |
| Pain Sensitivity Index | 328 | 0 | 27 | 8.2 |
| Distress Tolerance Scale | 328 | 0 | 27 | 8.2 |
| Fear Questionnaire Blood–Injection Subscale | 328 | 0 | 27 | 8.2 |
| Client Satisfaction Questionnaire b | 226 | 19 | 8.4 | |
| Change in Distress and Interference Ratings from ADIS‐5 | 334 | 0 | 15 | 4.49 |
| Time 6 (6‐month follow‐up) | ||||
| MDAS | 295 | 58 | 18.3 | |
| Time 7 (12‐month follow‐up) | ||||
| MDAS | 254 | 98 | 38.58 | |
N refers to the total number of individuals who completed assessments at each respective time point. ‘N Missing’ refers to the total number of individuals with missing data for a specific outcome measure administered at each respective time point. ‘% Missing’ refers to the number of individuals with missing data on a given outcome measure out of the total number of individuals who either completed the assessment at each respective time point or could not be reached for that specific timepoint.
Control participants are not given the Client Satisfaction Questionnaire and so do not appear in the total N for those measures.
Funding: This study was funded by a grant from the National Institute of Dental and Craniofacial Research NIDCR (#U01DE027328).
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.