Mechanisms of Acupuncture Analgesia on Experimental Dental Pain - A Psychophysical Study (Phase1) (MAC-DENT1)

Mechanisms of Acupuncture Analgesia on Experimental Dental Pain - A Randomized, Single Blinded, Sham-controlled Psychophysical Study (Phase1)

The investigators will assess the effects of manual acupuncture on experimental dental pain in 36 healthy subjects by means of subjective pain intensity ratings and pain-specific autonomic nervous system (ANS) reactions.

Study Overview

• Status: Completed
• Conditions: Experimental Dental Pain
• Intervention / Treatment: Procedure: Acupuncture; Procedure: Sham-Acupuncture; Procedure: No Acupuncture

Detailed Description

This psychophysical and -physiological study is the first part of a two-phase project which pursues to explore how acupuncture-induced pain modulation interacts with pain-specific brain processing patterns by means of functional magnetic resonance imaging (fMRI) and by using an experimental dental pain model.

In this preceding study, the characterization of manual acupuncture effects on the experimental dental pain model will be tested under laboratory conditions and without restrictions of an fMRI-measurement in order to provide a sound foundation for the following fMRI-experiment. Pain modulating effects of the manual acupuncture intervention (4 points: needle manipulation of bilateral large-intestine 4 (LI4), stomach 6 and 7 (ST6, ST7) ipsilateral to the stimulated tooth) will be compared to sham-acupuncture (insertion and manipulation of 4 non-acupuncture points) and a control intervention (no acupuncture) which will each be performed at 3 different days in a randomized order. Intervention effects on experimental dental pain will be assessed by testing of 36 healthy volunteers by means of subjective pain intensity ratings and pain-specific ANS reactions such as electrodermal activity and heart rate/respiratory changes. Besides laying the groundwork for the following fMRI experiment, this study could provide valuable basic insights into the dynamics of the tested manual acupuncture effects and further provide important knowledge for the planning of future clinical studies encompassing dental conditions and development of acupuncture treatments.

• Study Type: Interventional
• Enrollment (Actual): 35
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Zurich, Switzerland, 8032
    • Clinic of Masticatory Disorders, Removable Prosthodontics, Geriatric and Special Care Dentistry Center of Dental Medicine University of Zurich
  • Zurich, Switzerland, 8091
    • Institute for Complementary and Integrative Medicine, University Hospital Zurich

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 40 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• right-handed
• Written informed consent
• Fluent in German language
• Sufficient dental sensitivity for the tooth stimulation
• No acupuncture treatment in the previous 12 months
• No medical knowledge about acupuncure

Exclusion Criteria:

• Alcohol, drug, and analgesics consumption within the last 24 hours
• Complaints of diseases of the oral cavity
• Pre-existing neurological and(or psychiatric conditions
• History of severe dental pain
• Regular intake of pain medication
• History of brain injuries
• Alcohol and drug abuse
• Chronic diseases that require a permanent intake of drugs

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: Single

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Healthy subjects; All subjects participate at 3 experimental conditions (Acupuncture, Sham-Acupuncture and No Acupuncture) at 3 different days in a randomized order.	Procedure: Acupuncture; Needle insertion and manipulation at 4 acupuncture points (bilateral LI4, right ST6 and ST7).; Other Names: Verum Acupuncture; Procedure: Sham-Acupuncture; Needle insertion and manipulation at 4 non-acupoints; Procedure: No Acupuncture; Control intervention: No needle insertion and manipulation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Comparison of the - mean post-pre acupuncture intervention pain intensity rating differences - and mean post-pre control intervention (no acupuncture) rating differences		15 minutes
Comparison of the - mean post-pre acupuncture intervention pain intensity rating differences - and mean post-pre sham-acupuncture rating differences	In case of a significant effect in outcome 1, outcome 2 will be tested using a hierarchical procedure in order to avoid multiple testing.	15 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Longer lasting effects of acupuncture on subjective intensity ratings	Besides the pre-post intervention comparisons (primary outcome), 2 additional timepoints (Total: pre-intervention, post-intervention, 15 min post-intervention, 30 min post-intervention) will be examined to test differences in temporal dynamics between the 3 intervention effects on subjective pain intensity.	50 minutes
Longer lasting effects of acupuncture on pain-specific changes in heart rate.	Besides the pre-post intervention comparisons (primary outcome), 2 additional timepoints (Total: pre-intervention, post-intervention, 15 min post-intervention, 30 min post-intervention) will be examined to test differences in temporal dynamics between the 3 intervention effects on pain-specific heart rate alterations.	50 minutes
Longer lasting effects of acupuncture on pain-specific changes in skin conductance.	Besides the pre-post intervention comparisons (primary outcome), 2 additional timepoints (Total: pre-intervention, post-intervention, 15 min post-intervention, 30 min post-intervention) will be examined to test differences in temporal dynamics between the 3 intervention effects on pain-specific skin conductance alterations.	50 minutes
Longer lasting effects of acupuncture on pain-specific changes in respiratory frequency.	Besides the pre-post intervention comparisons (primary outcome), 2 additional timepoints (Total: pre-intervention, post-intervention, 15 min post-intervention, 30 min post-intervention) will be examined to test differences in temporal dynamics between the 3 intervention effects on pain-specific changes in respiratory frequency.	50 minutes
Changes in skin conductance during the three intervention types (acupuncture, sham-Acupuncture, no acupuncture).	Comparison of changes in the skin conductance measured during the acupuncture/sham-acupuncture and no acupuncture	10 minutes
Changes in heart rate variability (HRV) during the three intervention types (acupuncture, sham-Acupuncture, no acupuncture).	Comparison of changes in the HRV measured during the acupuncture/sham-acupuncture and no acupuncture	10 minutes
Changes in respiratory frequency during the three intervention types (acupuncture, sham-Acupuncture, no acupuncture).	Comparison of changes in respiratory frequency measured during the acupuncture/sham-acupuncture and no acupuncture.	10 minutes
Frequency of SAEs	Serious adverse event (SAEs) occurrences will be recorded and their frequency will be calculated.	1 month

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Expectation towards acupuncture	Acupuncture expectation will be assessed using an acupuncture expectation questionnaire developed by the Institut for Complementary and Integrative Medicine, University Hospital Zurich	60 minutes
Anxiety states and traits	For the assessment of anxiety levels, the State-Trait Anxiety Inventory(STAI)(Bieling et al., 1998) questionnaire will be applied.	60 minutes

Collaborators and Investigators

• Sponsor: University of Zurich
• Collaborators: Charite University, Berlin, Germany; First Teaching Hospital of Tianjin University of Traditional Chinese Medicine
• Investigators: Principal Investigator: Claudia M Witt, MD, University of Zurich

Publications and helpful links

General Publications

• Bieling PJ, Antony MM, Swinson RP. The State-Trait Anxiety Inventory, Trait version: structure and content re-examined. Behav Res Ther. 1998 Jul-Aug;36(7-8):777-88. doi: 10.1016/s0005-7967(98)00023-0.
• de Matos NMP, Pach D, Xing JJ, Barth J, Beyer LE, Shi X, Kern A, Lukic N, Ettlin DA, Brugger M, Witt CM. Evaluating the Effects of Acupuncture Using a Dental Pain Model in Healthy Subjects - A Randomized, Cross-Over Trial. J Pain. 2020 Mar-Apr;21(3-4):440-454. doi: 10.1016/j.jpain.2019.08.013. Epub 2019 Sep 12.

Study record dates

Study Major Dates

• Study Start: October 1, 2015
• Primary Completion (Actual): March 1, 2016
• Study Completion (Actual): March 1, 2016

Study Registration Dates

• First Submitted: October 23, 2015
• First Submitted That Met QC Criteria: October 26, 2015
• First Posted (Estimate): October 28, 2015

Study Record Updates

• Last Update Posted (Estimate): March 15, 2016
• Last Update Submitted That Met QC Criteria: March 14, 2016
• Last Verified: March 1, 2016

More Information

Terms related to this study

• Keywords: Autonomic nervous system; Psychophysics; Manual acupuncture; Experimental dental pain; Subjective pain ratings
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Stomatognathic Diseases; Tooth Diseases; Facial Pain; Toothache
• Other Study ID Numbers: MAC-DENT-Psy