A Preliminary Genome-Wide Association Study of Pain-Related Fear: Implications for Orofacial Pain

Genetics of constant and severe pain in the NAPS2 cohort of recurrent acute and chronic pancreatitis patients

Recurrent acute and chronic pancreatitis (RAP, CP) are complex, progressive inflammatory diseases with variable pain experiences impacting patient function and quality of life. The genetic variants and pain pathways in patients contributing to most severe pain experiences are unknown. We used previously genotyped individuals with RAP/CP from the North American Pancreatitis Study II (NAPS2) of European Ancestry for nested genome-wide associated study (GWAS) for pain-severity, chronicity, or both. Lead variants from GWAS were determined using FUMA. Loci with p<1e-5 were identified for post-hoc candidate identification. Transcriptome-wide association studies (TWAS) identified loci in cis and trans to the lead variants. Serum from phenotyped individuals with CP from the PROspective Evaluation of Chronic Pancreatitis for EpidEmiologic and Translational StuDies (PROCEED) was assessed for BDNF levels using Meso Scale Discovery Immunoassay. We identified four pain systems defined by candidate genes: 1) Pancreas-associated injury/stress mitigation genes include: REG gene cluster, CTRC, NEURL3 and HSF22. 2) Neural development and axon guidance tracing genes include: SNPO, RGMA, MAML1 and DOK6 (part of the RET complex). 3) Genes linked to psychiatric stress disorders include TMEM65, RBFOX1, and ZNF385D. 4) Genes in the dorsal horn pain-modulating BDNF/neuropathic pathway included SYNPR, NTF3 and RBFOX1. In an independent cohort BDNF was significantly elevated in patients with constant-severe pain. Extension and expansion of this exploratory study may identify pathway- and mechanism-dependent targets for individualized pain treatments in CP patients. PERSPECTIVE: Pain is the most distressing and debilitating feature of chronic pancreatitis. Yet many patients with chronic pancreatitis have little or no pain. The North American Pancreatitis Study II (NAPS2) includes over 1250 pancreatitis patients of all progressive stages with all clinical and phenotypic characteristics carefully recorded. Pain did not correlate well with disease stage, inflammation, fibrosis or other features. Here we spit the patients into groups with the most severe pain and/or chronic pain syndromes and compared them genetically with patients reporting mild or minimal pain. Although some genetic variants associated with pain were expressed in cells (1) of the pancreas, most genetic variants were linked to genes expressed in the nervous system cells associated with (2) neural development and axon guidance (as needed for the descending inhibition pathway), (3) psychiatric stress disorders, and (4) cells regulating sensory nerves associated with BDNF and neuropathic pain. Similar and overlapping genetic variants in systems 2 -4 are also seen in pain syndromes form other organs. The implications for treating pancreatic pain are great in that we can no longer focus on just the pancreas. Furthermore, new treatments designed for pain disorders in other tissues may be effective in some patient with pain syndromes from the pancreas. Further research is needed to replicate and extend these observations so that new, genetics-guided rational treatments can be developed and delivered.

X chromosome-wide association study of quantitative biomarkers from the Alzheimer's Disease Neuroimaging Initiative study

Introduction

Alzheimer's disease (AD) is a complex neurodegenerative disease with high heritability. Compared to autosomes, a higher proportion of disorder-associated genes on X chromosome are expressed in the brain. However, only a few studies focused on the identification of the susceptibility loci for AD on X chromosome.

Methods

Using the data from the Alzheimer's Disease Neuroimaging Initiative Study, we conducted an X chromosome-wide association study between 16 AD quantitative biomarkers and 19,692 single nucleotide polymorphisms (SNPs) based on both the cross-sectional and longitudinal studies.

Results

We identified 15 SNPs statistically significantly associated with different quantitative biomarkers of the AD. For the cross-sectional study, six SNPs (rs5927116, rs4596772, rs5929538, rs2213488, rs5920524, and rs5945306) are located in or near to six genes DMD, TBX22, LOC101928437, TENM1, SPANXN1, and ZFP92, which have been reported to be associated with schizophrenia or neuropsychiatric diseases in literature. For the longitudinal study, four SNPs (rs4829868, rs5931111, rs6540385, and rs763320) are included in or near to two genes RAC1P4 and AFF2, which have been demonstrated to be associated with brain development or intellectual disability in literature, while the functional annotations of other five novel SNPs (rs12157031, rs428303, rs5953487, rs10284107, and rs5955016) have not been found.

Discussion

15 SNPs were found statistically significantly associated with the quantitative biomarkers of the AD. Follow-up study in molecular genetics is needed to verify whether they are indeed related to AD. The findings in this article expand our understanding of the role of the X chromosome in exploring disease susceptibility, introduce new insights into the molecular genetics behind the AD, and may provide a mechanistic clue to further AD-related studies.

Psychometric evaluation of the Japanese version of the fear of pain questionnaire-III and its association with dental anxiety: a cross-sectional study

BACKGROUND

Fear of pain is a significant concern related to chronic pain and its impact on daily functioning. It is also associated with dental anxiety, highlighting its relevance in dental practice. This study aimed to validate the Japanese version of the Fear of Pain Questionnaire-III (FPQ-III) and explore its relationship with dental anxiety.

METHODS

400 participants completed the Japanese version of the FPQ-III, with 100 participants re-evaluated after one month. Convergent validity was tested against dental anxiety and pain catastrophizing, while discriminant validity was assessed by examining general anxiety and depression correlations. Confirmatory factor analysis was used to examine the factorial validity of the FPQ-III and a shortened version of the FPQ-III (FPQ-9). Item response theory was applied for each subscale to estimate the discriminative power of each item and draw a test information curve. Structural equation modeling (SEM) was used to investigate the relationship between fear of pain and dental anxiety.

RESULTS

Data from 400 participants (200 women, 44.9 ± 14.5 years) were analyzed. The FPQ-III showed good internal validity, intra-examiner reliability, discriminant validity, and convergent validity. Confirmatory factor analysis results supported a three-factor structure, and the FPQ-9 showed a good fit. Test information curves demonstrated that the FPQ-9 maintained high accuracy over a similarly wide range as the FPQ-III. SEM revealed that fear of minor pain was associated with dental anxiety via fear of medical pain even in individuals without painful medical or dental experiences (indirect effect 0.48 [95% CI: 0.32-0.81]). Fear of severe pain tended to be higher in individuals with chronic pain compared to those without (latent mean values 0 vs. 0.27, p = 0.002) and was also associated with dental anxiety via fear of medical pain in women (indirect effect 0.15 [95% CI: 0.01-0.34]).

CONCLUSION

The Japanese version of the FPQ-9 demonstrated high reliability and validity, making it a valuable tool in dental clinical and research settings. It provides insights into the fear of pain among individuals with chronic pain and dental anxiety, informing potential intervention strategies.

Classical trigeminal neuralgia is associated with gephyrin and sodium voltage-gated channel alpha subunit 8

Trigeminal neuralgia is highly debilitating, and its etiology is still undefined. The goal of this work was to define associations between well-characterized trigeminal neuralgia cases and common genetic variants in the population. two hundred and fifty-seven individuals diagnosed with classical trigeminal neuralgia were compared to 865 individuals without classical trigeminal neuralgia and with an assessment for lower or higher pain threshold based on the amount of anesthetic required for routine dental treatment. Genotypes of 24 variants marking genes in the VGSC (voltage-gated sodium channels) or GABA (gamma-aminobutyric acid) pathways were obtained using TaqMan chemistry end end-point analysis. Chi-square was used for all comparisons with an alpha of 0.002. An association between classical trigeminal neuralgia and individuals requiring less or more anesthetic for routine dental treatments showed associations with SCN8A rs1601012 and GPHN rs723432 (p = 0.0009 and p = 0.0002, respectively). In conclusion, classical trigeminal neuralgia is associated with SCN8A and GPHN and markers rs1601012 rs723432 may be useful to determine individual risks for the condition.

SFRP4+IGFBP5hi NKT cells induced neural-like cell differentiation to contribute to adenomyosis pain

Background

Adenomyosis is an estrogen-dependent gynecological disease. The pathogenesis of chronic pain, the main clinical symptom of adenomyosis, remains undefined. As a combination lymphocyte with both T-cell and natural killer (NK)-cell properties, NK T (NKT) cells play a role in immune defense against numerous diseases and modulate cell differentiation.

Method

This study analyzed the tissue-cell samples from adenomyosis with or without pain by single-cell sequencing.

Result

We found a specific population of secreted frizzled-related protein 4 (SFRP4)⁺NKT cells and a large amount of undifferentiated multipotent stem cells in the adenomyosis pain group. We discovered that a high expression of IGFBP5 in SFRP4⁺NKT cells could promote the differentiation of multipotent stem cells into neural-like cells via the single-cell trajectory. Through verification by the sample, we found that the degree of the expression of the neuronal marker NEFM was correlated with the duration of pain in adenomyosis patients. The expression of IGFBP5 was positively correlated with the pain scores of adenomyosis patients.

Conclusion

Collectively, these findings suggest that SFRP4⁺IGFBP5^hi NKT cells were capable of converting part of the stem cells into neurogenic cells and inducing adenomyosis pain.

Genome-wide Scan of Dental Fear and Anxiety Nominates Novel Genes

Dental care-related fear and anxiety (DFA) is prevalent, affects oral health care utilization, and is related to poor oral health and decreased quality of life. In addition to learned and cultural factors, genetics is hypothesized to contribute to DFA. Therefore, we performed a genome-wide association study to identify genetic variants contributing to DFA. Adult and adolescent participants were from 4 cohorts (3 from the US-based Center for Oral Health Research in Appalachia, n = 1,144, 1,164, and 535, and the UK-based Avon Longitudinal Study of Parents and Children [ALSPAC], n = 2,078). Two self-report instruments were used to assess DFA: the Dental Fear Survey (US cohorts) and Corah's Dental Anxiety Scale (ALSPAC). Genome-wide scans were performed for the DFA total scores and subscale scores (avoidance, physiological arousal, fear of dental treatment-specific stimuli), adjusting for age, sex, educational attainment, recruitment site, and genetic ancestry. Results across cohorts were combined using meta-analysis. Heritability estimates for DFA total and subscale scores were similar across cohorts and ranged from 23% to 59%. The meta-analysis revealed 3 significant (P < 5E-8) associations between genetic loci and 2 DFA subscales: physiological arousal and avoidance. Nearby genes included NTSR1 (P = 3.05E-8), DMRTA1 (P = 4.40E-8), and FAM84A (P = 7.72E-9). Of these, NTSR1, which was associated with the avoidance subscale, mediates neurotensin function, and its deficiency may lead to altered fear memory in mice. Gene enrichment analyses indicated that loci associated with the DFA total score and physiological arousal subscale score were enriched for genes associated with severe and persistent mental health (e.g., schizophrenia) and neurocognitive (e.g., autism) disorders. Heritability analysis indicated that DFA is partly explained by genetic factors, and our association results suggested shared genetic underpinnings with other psychological conditions.

Genome-wide association study of pain sensitivity assessed by questionnaire and the cold pressor test

ABSTRACT

We deployed an online pain sensitivity questionnaire (PSQ) and an at-home version of the cold pressor test (CPT) in a large genotyped cohort. We performed genome-wide association studies on the PSQ score (25,321 participants) and CPT duration (6853). We identified one new genome-wide significant locus associated with the PSQ score, which was located in the TSSC1 (also known as EIPR1 ) gene (rs58194899, OR = 0.950 [0.933-0.967], P -value = 1.9 × 10 -8 ). Although high pain sensitivity measured by both PSQ and CPT was associated with individual history of chronic and acute pains, genetic correlation analyses surprisingly suggested an opposite direction: PSQ score was inversely genetically correlated with neck and shoulder pain ( rg = -0.71), rheumatoid arthritis (-0.68), and osteoarthritis (-0.38), and with known risk factors, such as the length of working week (-0.65), smoking (-0.36), or extreme BMI (-0.23). Gene-based analysis followed by pathway analysis showed that genome-wide association studies results were enriched for genes expressed in the brain and involved in neuronal development and glutamatergic synapse signaling pathways. Finally, we confirmed that females with red hair were more sensitive to pain and found that genetic variation in the MC1R gene was associated with an increase in self-perceived pain sensitivity as assessed by the PSQ.

Effects of hypnosis versus enhanced standard of care on postoperative opioid use after total knee arthroplasty: the HYPNO-TKA randomized clinical trial

BACKGROUND

Hypnosis decreases perioperative pain and has opioid-sparing potential but has not been rigorously studied in knee arthroplasty. This trial investigates the impact of perioperative hypnosis on inpatient opioid use following total knee arthroplasty.

METHODS

This prospective randomized controlled trial was conducted at a single academic medical center. The hypnosis arm underwent a scripted 10 min hypnosis session prior to surgery and had access to the recorded script. The control arm received hypnosis education only. The primary outcome was opioid use in milligram oral morphine equivalents per 24 hours during hospital admission. A secondary analysis was performed for patients taking opioids preoperatively.

RESULTS

64 primary knee arthroplasty patients were randomized 1:1 to hypnosis (n=31) versus control (n=33) and included in the intent-to-treat analysis. The mean (SD) postoperative opioid use in oral morphine equivalents per 24 hours was 70.5 (48.4) in the hypnosis versus 90.7 (74.4) in the control arm, a difference that was not statistically significant (difference -20.1; 95% CI -51.8 to 11.4; p=0.20). In the subgroup analysis of the opioid-experienced patients, there was a 54% daily reduction in opioid use in the hypnosis group (82.4 (56.2) vs 179.1 (74.5) difference of -96.7; 95% CI -164.4 to -29.0; p=<0.01), equivalent to sparing 65 mg of oxycodone per day.

CONCLUSION

Perioperative hypnosis significantly reduced inpatient opioid use among opioid-experienced patients only. A larger study examining these findings is warranted.

TRIAL REGISTRATION NUMBER

NCT03308071.

Phantosmia and psychogenic non-epileptic seizures in a patient with burning mouth syndrome suffering from severe depression

Burning mouth syndrome (BMS) is a rare but serious medical condition with important psychiatric comorbidity and specific psychological correlates. Psychopathology related with BMS represents a real challenge for clinical decision-making. In this case, depression is the leading psychiatric diagnosis associated with patient's BMS somatic pain and is driven by anxiety and a dissociative functioning. Facing a complex psychosomatic symptomatology, we offer new clinical perspectives for the screening of psychological traits of BMS. Moreover, we highlight the need to foster interdisciplinarity to improve differential diagnosis and defining an optimal care path. This case report stimulates a reflection on management challenges for the consultation-liaison psychiatry and shows the importance of a person-centred approach when communicating the diagnosis.

The Effect of Pain Experienced During the COVID-19 Infection on the Fear of Pain and Quality of Life

Aims

This study was conducted to determine the effect of pain experienced during the COVID-19 infection on the fear of pain and quality of life of individuals.

Background

Pain is a complex, multidimensional, neurophysiological and psychosocial experience known only to the person experiencing pain. Although there are studies showing that individuals with COVID-19 experience pain, there are no studies that evaluate the relationship between fear of pain and quality of life of people after COVID-19 infection.

Design

The study was carried out as descriptive, comparative and correlational design.

Methods

Snowball sampling method was used in the research and the data were collected online. A total of 404 individuals participated in the study. The data were collected using the Descriptive Characteristics Questionnaire, Numeric Rating Scale, Fear of Pain Questionnaire-III and The 36-Item Short Form Health Survey Questionnaire.

Results

It was determined that 87.1% of the individuals experienced pain during COVID-19 and the mean intensity of this pain was 6.16 ± 2.75. In addition, 37.1% of the individuals experienced pain for a while after COVID-19 and the mean intensity of this pain was 3.81 ± 3.00. The individuals who experienced pain during COVID-19 had higher fear of pain and lower quality of life than those who did not experience pain. There was a significant correlation between the severity of pain experienced during COVID-19 with the fear of pain and the quality of life.

Conclusions

According to the results of the study, it can be said that individuals who experienced intense pain during COVID-19 infection have higher fear of pain and lower quality of life. In addition, as the fear of pain increases, the quality of life of individuals decreases.

High incidence of acute self-reported sleep disturbances in patients following arthroscopic-assisted knee surgery

OBJECTIVES

To evaluate the self-reported incidence of sleep disturbances, defined as ≤7 hours of sleep per 24-hour period, in patients undergoing arthroscopic-assisted knee surgery.

METHODS

Patients who underwent arthroscopic knee surgery over the course of a 4-month period were prospectively included. Patients were excluded if a history of insomnia or other sleep altering medical history was reported. Self-reported sleep metrics included average number of hours of sleep per night, average number of awakenings during sleep per night, perceived quality of sleep, average pain level during sleep and number of hours of physical activity/therapy per week. Data were collected at weeks 1, 3, and 6 postoperatively. Joint circumference was measured on postoperative day 1 and served as an indicator of a knee effusion. Paired t-tests were used to compare preoperative to postoperative hours of sleep. Simple and multiple linear regression were used to evaluate relationships between surgical variables and postoperative sleep metrics.

RESULTS

There were 123 patients who underwent arthroscopic knee surgery during the prospective enrolment period; 83 patients were included in the final analysis. The overall incidence of preoperative sleep disturbances was 20% (n=17). The overall incidence of self-reported postoperative sleep disturbances was 99%, 96% and 90% at weeks 1, 3 and 6, respectively. The average number of hours slept was significantly reduced at 1, 3 and 6 weeks postoperatively compared with the preinjury state (p<0.001). Knee joint circumference had a significantly negative correlation with average number of hours of sleep in the first 6 weeks postoperatively (R=-0.704; p=0.001). Surgical variables including severity of surgery, weekly postoperative pain level and weekly hours of postoperative physical therapy were not significant independent predictors of acute postoperative sleep disturbances (p>0.05).

CONCLUSION

Sleep disturbances were commonly reported in patients following arthroscopic knee surgery without correction of sleep metrics by 6 weeks postoperatively. The majority of sleep disturbances in this cohort correlated with an increased knee effusion. A multidisciplinary team approach is recommended to counsel patients regarding the potential for and problems with acute sleep disturbances following arthroscopic knee surgery.Level of evidence: 3.

Sources of Individual Differences in Pain

Pain is an immense clinical and societal challenge, and the key to understanding and treating it is variability. Robust interindividual differences are consistently observed in pain sensitivity, susceptibility to developing painful disorders, and response to analgesic manipulations. This review examines the causes of this variability, including both organismic and environmental sources. Chronic pain development is a textbook example of a gene-environment interaction, requiring both chance initiating events (e.g., trauma, infection) and more immutable risk factors. The focus is on genetic factors, since twin studies have determined that a plurality of the variance likely derives from inherited genetic variants, but sex, age, ethnicity, personality variables, and environmental factors are also considered.

Cost-utility analysis of a multicomponent intervention for fibromyalgia syndrome in primary care versus usual clinical practice: study protocol for an economic evaluation of a randomised control trial

INTRODUCTION

Fibromyalgia syndrome (FMS) imposes a high cost on society. The significant economic burden from the use of healthcare and, especially, social resources is a spur to revising the usual clinical care (UCC) and to improving treatment strategies. FMS has a deleterious effect on the quality of life (QOL) and productivity, which considerably increase the indirect costs to society. This study reports an economic evaluation comparing the cost and health benefits in a multicomponent intervention programme and UCC of patients with FMS who attend primary healthcare centres of the Gerència Territorial Terres de L'Ebre region of Catalonia, Spain. This article is linked to the pre-results of a randomised control trial study on the implementation of this intervention programme (ClinicalTrials.gov: NCT04049006).

METHOD AND ANALYSIS

A cost-utility analysis will be conducted from a societal perspective. Quality-adjusted life years will be calculated from the results of the SF-36 questionnaire, a QOL measurement instrument. Direct and indirect healthcare costs will be obtained from official prices and reports published by the Spanish Public Health Administration and the National Statistics Institute. The incremental cost-utility ratio will be estimated to compare the two healthcare practices. Deterministic sensitivity analysis will also be used to compare different cost scenarios, modifying the items with the highest weight in the cost composition.

ETHICS AND DISSEMINATION

The Clinical Research Ethics Committee of the IDIAPJGol Institute approved this study on 25 April 2018 (code P18/068) in accordance with the Helsinki/Tokyo Declaration. Information will be provided orally and in writing to participants, and their informed consent will be required. Participant anonymity will be guaranteed. The dissemination strategy includes publications in scientific journals and presentations in local and national media and at academic conferences. Trial registration number: NCT04049006; Pre-results.

Does the presence of cranial contrast spread during a sacroiliac joint injection predict short-term outcome?

BACKGROUND

The innervation of the sacroiliac joint (SIJ) is complex, with a dual innervation originating from the lumbosacral plexus anteriorly as well as the sacral lateral branches posteriorly. Nociceptors are found in intra-articular structures as well as periarticular structures. In patients with SIJ pain, a fluoroscopy-guided SIJ injection is usually performed posteriorly into the bottom one-third of the joint with local anesthetic and corticosteroids, but this does not always reach all intra-articular structures. The correlation between a cranial contrast spread and clinical success is undetermined in patients with SIJ pain.

METHODS

In a tertiary referral pain center, electronic medical records of patients who underwent an SIJ injection were retrospectively analyzed. Only patients with at least three positive provocation maneuvers for SIJ pain were selected. Contrast images of the SIJ were classified as with or without cranial spread on fluoroscopy as a marker of intra-articular injection. Clinical success was defined as ≥50% improvement in the patient's global perceived effect after 3-4 weeks. The primary outcome was defined as the correlation between cranial contrast spread and clinical success after an SIJ injection.

RESULTS

128 patients in total were included. In 68 patients (53.1%) fluoroscopy showed cranial contrast spread. Clinical success was higher in patients with cranial spread of contrast (55 of 68, 81%) versus those without (35 of 60, 58%) (p=0.0067). In a multivariable analysis with age, gender, presence of rheumatoid arthritis, side, and number of positive provocation maneuvers, the cranial spread of contrast remained the only independent factor of clinical success (p=0.006; OR 3.2, 95% CI 1.4 to 7.7).

CONCLUSION

In patients with SIJ pain, identified by positive pain provocation maneuvers, cranial contrast spread as a marker of intra-articular injection, with subsequent injection of 3 mL of local anesthetic and methylprednisolone 40 mg, was significantly correlated with clinical success up to 4 weeks. Therefore, attempts should be made to reach this final needle position before injecting local anesthetic and corticosteroids. This result needs to be confirmed in a high-quality prospective trial.

A Framework for Understanding the Role of Psychological Processes in Disease Development, Maintenance, and Treatment: The 3P-Disease Model

Health psychology is multidisciplinary, with researchers, practitioners, and policy makers finding themselves needing at least some level of competency in a variety of areas from psychology to physiology, public health, and others. Given this multidisciplinary ontology, prior attempts have been made to establish a framework for understanding the role of biological, psychological, and socio-environmental constructs in disease development, maintenance, and treatment. Other models, however, do not explain how factors may interact and develop over time. The aim here was to apply and adapt the 3P model, originally developed and used in the treatment of insomnia, to couch the biopsychosocial model in a way that explains how diseases develop, are maintained, and can be treated. This paper outlines the role of predisposing, precipitating, and perpetuating factors in disease states and conditions (the 3Ps) and provides examples of how this model may be adapted and applied to a number of health-related diseases or disorders including chronic pain, gastrointestinal disorders, oral disease, and heart disease. The 3P framework can aid in facilitating a multidisciplinary, theoretical approach and way of conceptualizing the study and treatment of diseases in the future.

Effects of Pretreatment Exposure to Dental Practice Using a Smartphone Dental Simulation Game on Children's Pain and Anxiety: A Preliminary Double-Blind Randomized Clinical Trial

OBJECTIVES

Studies on modeling a pre-exposure technique for the prevention of anxiety in children are rare, and there is no study on interactive modeling using computer games. We assessed the effect of playing a dental simulation game before operation on pain and anxiety in 4- to 7-year-old children during their first dental treatment session.

MATERIALS AND METHODS

In this double-blind randomized clinical trial, 50 children needing unilateral pulpotomy and placement of stainless-steel crowns (SSC) on mandibular primary first molars were enrolled and randomly divided into experimental (a simulation game) and control (no intervention) groups. The experimental group played the game twice a day for two weeks before the scheduled visit. At the dental session, their pre- and post-operative pains were recorded using the Wong-Baker Facial Rating Scale (W-BFRS). Also, heart rate (HR; as an indicator of anxiety) was measured using a finger pulse oximeter at six treatment stages: (1) baseline (at the initial session, two weeks before treatment) and (2-6) during different stages of treatment. Effects of playing the simulation on pain and HR were analyzed using t-test and repeated-measures two-way analysis of covariance (ANCOVA).

RESULTS

Game playing significantly reduced the HR (P=0.031). The interaction of playing with the treatment period was also significant (P=0.004). When the groups were compared in each of the six time points, the experimental group showed reduced HR during anesthetic injection and cavity preparation using a high-speed handpiece (P<0.003).

CONCLUSIONS

Based on the results, playing certain dental simulation games before the first dental visit might reduce the anxiety felt during anesthetic injections and drilling.