Condition category
Oral Health
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Mr Stephen Daniels


Contact details

SCIREX Research Center/ Premier Research Group
3200 Red River
Suite 300
TX 78705
United States of America

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Comparing the analgesic efficacy of Advil® and Tylenol® Extra Strength, separately and in combination, in patients experiencing postoperative dental pain: A double blind, randomised, placebo controlled, parallel group trial with modified factorial design


Study hypothesis

The objective of this study was to compare the analgesic efficacy of Advil® tablets (200 or 400 mg ibuprofen) given concurrently with Tylenol® Extra Strength (ES) caplets (500 or 1000 mg acetaminophen [paracetamol]) to:
1) Advil tablets (400mg ibuprofen) alone;
2) Tylenol ES caplets (1000mg acetaminophen) alone;
3) Placebo
among subjects experiencing moderate to severe postoperative dental impaction pain. Analgesic efficacy was measured in terms of total effect, peak effect, onset and duration of effect, and subject’s overall assessment of the study medication.

A secondary objective was to evaluate the tolerability (adverse event [AE] profile) of the combination of Advil tablets (200 or 400 mg ibuprofen) given concurrently with Tylenol Extra Strength (500 or 1000 acetaminophen) to the individual ingredients and to placebo.

Ethics approval

Quorum Review (Seattle, WA) independent institutional review board (IRB) approved on the 8th of October 2004

Study design

Randomised double blind placebo controlled single dose modified factorial design study using the dental impaction pain model

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use contact details below to request a patient information sheet


Dental Pain


Subjects were randomly allocated to one of the 5 treatment groups:
1. 400mg Ibuprofen alone
2. 1000mg Acetaminophen alone
3. 400mg Ibuprofen plus 1000mg acetaminophen
4. 200mg Ibuprofen plus 500mg acetaminophen
5. Placebo

Intervention type



Phase IV

Drug names

Primary outcome measure

Sum of Pain Relief and Pain Intensity Differences from 0-8 hours (SPRID 0-8)

Secondary outcome measures

1. Total Pain Relief from 0 to 8 hours (TOTPAR 0-8)
2. Sum of the Pain Intensity Differences from 0 to 8 hours (SPID 0-8)
3. Sum of the Pain Intensity Differences on the VAS scale from 0 to 8 hours (SPID VAS 0-8)
4. TOTPAR, SPID, SPRID, and SPID VAS from 0 to 4 hours (0-4) and 0 to 6 hours (0-6)
5. Individual pain relief (PR) readings at each time point from 15 minutes to 8 hours
6. Peak PR recorded during the 8-hour evaluation period
7. Individual PID at each time point from 15 minutes to 8 hours
8. Individual PID for the VAS scale (PID VAS) at each time point from 15 minutes to 8 hours
9. Peak PID and peak PID VAS recorded during the 8-hour evaluation period
10. First time at which the PID was at least 1
11. Time to first perceptible pain relief
12. Time to first confirmed perceptible pain relief
13. Time to first meaningful pain relief
14. Time to use of rescue medication
15. Time to pain half gone
16. Subject’s overall (global) assessment

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Age: between the ages of 16 and 40 years of age
2. Sex: either male or female
3. Primary diagnosis: At least three impacted third molars (two of which must have been mandibular impacted molars) indicated for removal. Both mandibular impactions must have required bone removal, and there must have been a total score of 9 or greater on the impaction grading scale for the three or four impacted third molar
4. Baseline Pain Intensity: were experiencing postoperative pain of at least moderate based on the pain intensity categorical rating scale and a pain intensity VAS score of 50mm or greater on the 100mm VAS Scale
5. Consent: gave written informed consent. Subjects who were 16 or 17 years of age also required their parents or legal guardian to provide written informed consent in addition to their written assent

Participant type


Age group




Target number of participants

Analysed: 234

Total final enrolment


Participant exclusion criteria

1. Had a current history of significant disease deemed by the investigator to render the subject unsuitable for inclusion
2. Had any ongoing painful condition other than that associated with their third molar surgery
3. Had an ongoing condition that may have interfered with the absorption, distribution, metabolism or excretion of the study drug
4. Had a history of allergy (including angioedema, urticaria, bronchospasm and rhinitis) related to the treatment with ibuprofen, acetaminophen, aspirin, other NSAIDs or any other medication used in this study
5. A history of frequent peptic ulcers, duodenal ulcers or GI bleeding
6. A history of frequent dyspepsia, heartburn or indigestion
7. A history of migraine headaches within the past year
8. A history of psychotic illness, attempted suicide or neurosis
9. Those unable to refrain from smoking during their stay in the research centre
10. A positive history of drug or alcohol abuse within the past six months
11. Those who were taking any concomitant medication that might have confounded assessments of pain relief (PAR), such as: psychotropic drugs, antidepressants, sedative-hypnotics (other than those permitted for conscious sedation), or other analgesics taken within five times of their elimination half lives. Selective serotonin reuptake inhibitors (SSRIs) and serotonin noradrenalin reuptake inhibitors (SNRIs) were permitted if the subject had been on a stable dose for at least four weeks prior to visit 1 (screening)
12. Those who were unable, in the opinion of the investigator, to comply fully with the study requirements
13. Those previously randomised into this study
14. Those who had participated in a clinical trial in the previous 12 weeks. Twelve weeks (calculated from the time of last dosing in the prior trial to time of anticipated dosing in this trial)

Recruitment start date


Recruitment end date



Countries of recruitment

United States of America

Trial participating centre

SCIREX Research Center/ Premier Research Group
TX 78705
United States of America

Sponsor information


Reckitt Benckiser Healthcare (UK)

Sponsor details

Dansom Lane
United Kingdom

Sponsor type




Funder type


Funder name

Reckitt Benckiser Healthcare (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

2010 results in: (added 31/10/2019)

Publication citations

Additional files

Editorial Notes

31/10/2019: The following changes were made to the trial record: 1. Publication reference added. 2. The total final enrolment was added.