CompletedNCT02417337NSAIDUpdated Aug 10, 2026Results posted

Efficacy of Different Drugs to Control Post Root Canal Treatment Pain

A Phase 2 interventional study of Paracetamol and Ibuprofen in Pain, Postoperative Pain and Irreversible Pulpitis, sponsored by University of Khartoum. Completed at 1 site in Sudan. Open to participants aged 18 Years to 60 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-10.

Primary conditionPain, PostoperativeRegistry: PainReclassifiedWhy we changed it

Registry

Pain — the first condition term the registry derived for this study.

ClinicalTrials.gg

Pain, Postoperative

Why

The study's listed conditions name Pain, Postoperative, a narrower term within Pain.

Confidence

High: the new condition is named in the study's own listed conditions. Of 351 hand-checked studies reclassified this way, 68% were exactly right and 84% in the right disease family; the registry's first term was right for 5% (measured 2026-10-21). How we classify →

Wrong?

Tell us the study's main condition →

Sponsored by University of Khartoum · Phase 2, Interventional, and Treatment

Phase: Phase 2
Study type: Interventional
Enrollment: 185
Allocation: Randomized
Ages: 18 Years to 60 Years
Sex: All

Study summary

Root canal therapy will ideally eliminate post-endodontic pain but occasionally analgesics are needed to diminish the pain [Owatz et al 2007]. Development of pain after completion of root canal treatment may undermine patients' confidence in the procedure and the clinician [Albashaireh and Alnegrish 1998]. Non-steroidal anti-inflammatory drugs are one of the most frequently taken analgesic medications for dental pain. Their popularity attributed to their efficacy in relieving pain and fever and low side effect profile at therapeutic doses [Attar et al 2008]. Mono-therapy analgesic has a low effect on dental pain. Improvement was performance by combining analgesics with different mechanisms of action without raising any adverse effects [Mehlisch 2002], was effective in controlling moderate to severe pain. The combination of a non-steroidal anti-inflammatory drug (NSAID) and paracetamol has shown additive analgesia for treating dental pain in several studies [Breivik et al1999, Keiser and Hargreaves 2002]. Endodontic treatment with a lower prevalence of postoperative pain is usually the treatment of choice.There have been no controlled dental studies evaluating the additive effects of combining a non-steroidal anti-inflammatory drug with paracetamol. Breivik et al1999 \& Menhinick et al 2004 found that a combination of acetaminophen and ibuprofen was more effective than ibuprofen alone in managing postoperative pain [Breivik et al1999 \& Menhinick et al 2004]. Aim of the present study, to evaluate the efficacy of the paracetamol when used alone and in combinations with three groups of drugs to control postoperative endodontic pain.

Read the detailed description

Background: Management of pain is challenging part of dental treatment; sometimes pain is a major postoperative symptom after many dental procedures especially for endodontics. The aim of the present randomized clinical trial was to investigate the efficacy of using paracetamol alone and three combinations of non-steroidal anti-inflammatory drugs with paracetamol, to control postoperative endodontic pain.

Methodology: 185 patients who had anterior or premolar teeth with irreversible pulpitis without any signs and symptoms of apical periodontitis and with moderate to severe pain. Patients were divided by allocation randomization into five groups. Four experimental groups receiving different medication; group I (single dose of paracetamol); group II (ibuprofen / paracetamol); group III (mefenamic acid /paracetamol), group IV (diclofenac k / paracetamol) and group V (no medication group). The groups received the medication after the first appointment where the pulp removed, and canals fully prepared. Pain intensity was scored by using both verbal rating scale (VRS-4) and numerical rating scale (NRS-11). The pain scores were recorded before the initial endodontic therapy for up to 8 hours postoperatively. Sign test used for comparing pain score before and after treatment. This randomized control clinical trial was conducted on patients who were considered potential candidates if they had moderate to severe spontaneous pain of odontogenic origin (ranging from 4-10 score based on the numerical rating scale (NRS-11)). Patients were selected from those attending the Conservative dentistry clinics in both the University and the Teaching Hospital Emergency Clinic.

The medications were prepared in the laboratories of faculty of Pharmacy. Four groups of medications were prepared and a placebo as follows; Group I: paracetamol 1000mg Group II: ibuprofen 600mg + paracetamol 1000mg, Group III: Mefenamic acid 500mg + Paracetamol 1000mg Group IV: Diclofenac K 50mg + paracetamol 1000 mg Group V: Placebo

Conditions studied

Pain
Postoperative Pain
Irreversible Pulpitis

Browse trials for

Pain 10,054Registry's first term
Pain, Postoperative 5,640Primary · reclassified

In context

Pain, Postoperative Reclassified

5,640 studies on the registry are indexed under Pain, Postoperative; 1,230 are open to participants now.

This study's enrollment of 185 is above the median of 75 across 4,821 interventional studies indexed under Pain, Postoperative.

Browse Pain, Postoperative studies →

Lead sponsor

University of Khartoum is the lead sponsor of 14 studies on the registry; none are open to participants now.

Compared within Pain, Postoperative, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Pain. The counts are of registry records indexed under each term, refreshed daily. How we classify →

Who can participate

Ages eligible: 18 Years to 60 Years
Sexes eligible: All
Accepts healthy volunteers: Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

Spontaneous pain moderate to severe on the verbal rating scale (VRS-4), ranging from 4-10 score based on the numerical rating scale (NRS-11).
Adult patients presented for emergency endodontic treatment with a symptomatic maxillary or mandibular tooth (anterior and premolar) with a pulpal diagnosis of Irreversible pulpitis and normal periapex.
Patient choose to have root canal treatment for pain of endodontic origin.
The patient presented with (ASA) I or II medical history (ASA 1963).
The patient had read and thoroughly understood the pain score level sheet

Exclusion criteria

Exclusion Criteria:

Patients below 18 years of age;
Analgesic taken within the last 4 hours;
History of allergy to NSAIDs, paracetamol or local anaesthetics;
History of uncontrolled systemic disease [gastrointestinal (GI) disorders, oesophageal reflux, active asthma, decreased hepatic function, haemorrhagic disorders, or poorly controlled diabetes mellitus].
Patients currently taking opioids, monoamine oxidase inhibitors, tricyclic antidepressants, carbamazepine, diuretics, or anticoagulants;
There was history of opioid addiction or abuse; and
Pregnant or nursing female patients.

Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

ASA physical status: The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.

Study design

Phase: Phase 2
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel assignment
Masking: Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment: 185 participants (actual)

Study arms

Active comparator
Group I
paracetamol 1000mg
Drug: Paracetamol
Experimental
Group II
ibuprofen 600mg + paracetamol 1000mg,
Drug: Paracetamol · Drug: Ibuprofen
Experimental
Group III
Mefenamic acid 500mg + Paracetamol 1000mg
Drug: Paracetamol · Drug: Mefenamic Acid
Experimental
Group IV
Diclofenac K 50mg + paracetamol 1000 mg
Drug: Paracetamol · Drug: Diclofenac
Other
Group V
Placebo, no medication
Other: Placebo

Interventions

DrugParacetamol
NSAID
Also known as: Acetaminophen
DrugIbuprofen
NSAID
Also known as: isobutylphenyl propanoic acid
DrugMefenamic Acid
NSAID
Also known as: Fenamate
DrugDiclofenac
NSAID
Also known as: Voltaren
OtherPlacebo
empty double gelatinous capsules, having similar weight and appearance of the medications
Also known as: no medication

What researchers measure

Primary outcomes

Pain Scores Before and After 8 Hours of Treatment Per Group on the VRS-4 Scale
Pain was recorded in the verbal rating scale-4 (VRS-4 scale) before and after 8 hours of medication. The VRS-4 Scale has four categories of pain scores: no pain is the minimum (better outcome), slight pain, moderate pain, and severe pain score is the maximum (worse outcome).
Time frame: 8 hours
Pain Score on Numerical Rating Scale of Pain (NRS-11)
(NRS-11) numerical rating scale of pain between 0 (better) and 10 (worse) before and after treatment
Time frame: 8 hours

Secondary outcomes

Mean of Pain Reduction Stratified by Sex and Jaw Type on Numerical Rating Scale (NRS-11)
Numerical rating scale (NRS-11), (0 better/the least pain score to 10 worse/the maximum pain score), , was done for sex (male or female) and jaw type (maxilla or mandible)
Time frame: 8 hours

Results

Posted Jun 25, 2026

Limitations and caveats

One limitation was the time frame for the analysis of pain; more information would have been available if there were a 24-hour outcome line

Participant flow

The sample was made up of patients attending the clinics of the Faculty of Dentistry, University of Khartoum and the Khartoum Teaching Hospital emergency clinic, which were the setting and location of the trial. The clinical trial dates of recruitment was between August 2012 and August 2014.

Participant flow — Overall Study
Milestone	Group I	Group II	Group III	Group IV	Group V
Started	37	37	37	37	37
Completed	34	33	34	35	34
Not completed	3	4	3	2	3
Withdrew: Withdrawal by subject	2	1	2	2	0
Withdrew: Lost to follow-up	1	3	1	0	3

Outcome measures

PrimaryPain Scores Before and After 8 Hours of Treatment Per Group on the VRS-4 Scale

Pain was recorded in the verbal rating scale-4 (VRS-4 scale) before and after 8 hours of medication. The VRS-4 Scale has four categories of pain scores: no pain is the minimum (better outcome), slight pain, moderate pain, and severe pain score is the maximum (worse outcome).

Time frame:: 8 hours
Reported as:: Count of participants · Participants

Pain Scores Before and After 8 Hours of Treatment Per Group on the VRS-4 Scale
Participants	Group I	Group II	Group III	Group IV	Group V
Pain Scores before treatment per Group on the VRS-4 Scale — no pain	0	0	0	0	0
Pain Scores before treatment per Group on the VRS-4 Scale — slight pain	0	0	0	0	0
Pain Scores before treatment per Group on the VRS-4 Scale — moderate pain	12	8	7	15	12
Pain Scores before treatment per Group on the VRS-4 Scale — severe pain	22	25	27	20	22
8 hours after treatment per Group on the VRS-4 Scale — no pain	13	23	21	20	14
8 hours after treatment per Group on the VRS-4 Scale — slight pain	8	3	4	10	7
8 hours after treatment per Group on the VRS-4 Scale — moderate pain	4	4	7	1	6
8 hours after treatment per Group on the VRS-4 Scale — severe pain	9	3	2	4	7

Statistical analysis

Group I · Chi-squared · p = 0.771 · Chi-square statistic: 1.126
Group II · Chi-squared · p = 0.204 · Chi-square statistic: 4.591
Group III · Chi-squared · p = 0.833 · Chi-square statistic: 0.869
Group IV · Chi-squared · p = 0.158 · Chi-square statistic: 5.192
Group V · Chi-squared · p = 0.178 · Chi-square statistic: 4.912
Group I vs Group II vs Group III vs Group IV vs Group V · Chi-squared · p = 0.102 · Chi-square statistic: 6.216

PrimaryPain Score on Numerical Rating Scale of Pain (NRS-11)

(NRS-11) numerical rating scale of pain between 0 (better) and 10 (worse) before and after treatment

Time frame:: 8 hours
Reported as:: Median · score on a scale

Pain Score on Numerical Rating Scale of Pain (NRS-11)
score on a scale	Group I	Group II	Group III	Group IV	Group V
before treatment	8 (0 to 10)	8 (0 to 10)	8 (0 to 10)	8 (0 to 10)	8 (0 to 10)
after treatment	2.25 (0 to 10)	0.17 (0 to 10)	1.0 (0 to 10)	0.5 (0 to 10)	2.82 (0 to 10)

Statistical analysis

Group I · Sign test · p = 0.000 (the reported p-value was calculated) · Median difference (final values): 2.25"Median Difference (Final Values)" is accurate, as reported.
Group II · Sign test · p = 0.000 (the reported p-value was calculated) · Median difference (final values): 0.17"Median Difference (Final Values)" is accurate, as reported.
Group III · Sign test · p = 0.000 (the reported p-value was calculated) · Median difference (final values): 1.0"Median Difference (Final Values)" is accurate, as reported.
Group IV · Sign test · p = 0.000 (the reported p-value was calculated) · Median difference (final values): 0.5"Median Difference (Final Values)" is accurate, as reported.
Group V · Sign test · p = 0.000 (the reported p-value was calculated) · Median difference (final values): 2.82"Median Difference (Final Values)" is accurate, as reported.

SecondaryMean of Pain Reduction Stratified by Sex and Jaw Type on Numerical Rating Scale (NRS-11)

Numerical rating scale (NRS-11), (0 better/the least pain score to 10 worse/the maximum pain score), , was done for sex (male or female) and jaw type (maxilla or mandible)

Time frame:: 8 hours
Reported as:: Mean · score on a scale

Mean of Pain Reduction Stratified by Sex and Jaw Type on Numerical Rating Scale (NRS-11)
score on a scale	Group I	Group II	Group III	Group IV	Group V
male after 8 hours	3.8 (0 to 10)	1 (0 to 10)	0.4 (0 to 10)	0.43 (0 to 10)	1.94 (0 to 10)
male before treatment	6.6 (0 to 10)	6.8 (0 to 10)	7.2 (0 to 10)	7.57 (0 to 10)	7.35 (0 to 10)
female afte 8 hours	3.16 (0 to 10)	1.74 (0 to 10)	2.17 (0 to 10)	2.33 (0 to 10)	4.18 (0 to 10)
female before treatment	7.37 (0 to 10)	8 (0 to 10)	7.92 (0 to 10)	6.67 (0 to 10)	6.88 (0 to 10)
maxillary teeth after 8 hours	3.28 (0 to 10)	1.29 (0 to 10)	1.33 (0 to 10)	1.44 (0 to 10)	3.14 (0 to 10)
maxillary teeth before treatment	7.04 (0 to 10)	7.64 (0 to 10)	7.63 (0 to 10)	6.76 (0 to 10)	7.77 (0 to 10)
mandibular teeth after 8 hours	3.89 (0 to 10)	2.8 (0 to 10)	10 (0 to 10)	1.9 (0 to 10)	2.29 (0 to 10)
mandibular teeth before treatment	7.0 (0 to 10)	7.6 (0 to 10)	7.9 (0 to 10)	7.7 (0 to 10)	5.92 (0 to 10)

Statistical analysis

Group I vs Group II vs Group III vs Group IV vs Group V · Kruskal-Wallis · p = 0.000 (the reported p-value was calculated at a Significance level \<0.05) · Chi square of the meen rank: 14.41
Group I vs Group II vs Group III vs Group IV vs Group V · Kruskal-Wallis · p = 0.000 (the reported p-value was calculated at a Significance level \<0.05) · Chi square of the meen rank: 18.06
Group I vs Group II vs Group III vs Group IV vs Group V · Kruskal-Wallis · p = 0.000 (the reported p-value was calculated at a Significance level \<0.05) · Chi square of the meen rank: 23.252
Group I vs Group II vs Group III vs Group IV vs Group V · Kruskal-Wallis · p = 0.584 (the reported p-value was calculated at a Significance level \<0.05) · Chi square of the meen rank: 2.846

Adverse events

Collected over 2 years. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
Group I	0/34 (0%)	0/34 (0%)	0/34 (0%)
Group II	0/33 (0%)	0/33 (0%)	0/33 (0%)
Group III	0/34 (0%)	0/34 (0%)	0/34 (0%)
Group IV	0/35 (0%)	0/35 (0%)	0/35 (0%)
Group V	0/34 (0%)	0/34 (0%)	0/34 (0%)

Most frequent other events

Most frequent other events
Event	Group I	Group II	Group III	Group IV	Group V
GIT symptomsGastrointestinal disorders	0/34	0/33	0/34	0/35	0/34

Baseline characteristics

Patients reporting symptoms of irreversible pulpitis were requested to participate in the study, before intervention

Age, Categorical
Age, Categorical(Participants)	Group I	Group II	Group III	Group IV	Group V	Total
<=18 years	0	0	0	0	0	0
Between 18 and 65 years	34	33	34	35	34	170
>=65 years	0	0	0	0	0	0

Age, Continuous
Age, Continuous(years)	Group I	Group II	Group III	Group IV	Group V	Total
Mean	31.12 ± 8.92	43.12 ± 9.96	33.97 ± 11.62	32.97 ± 11.43	32.38 ± 10.47	33 ± 10.5

Sex: Female, Male
Sex: Female, Male(Participants)	Group I	Group II	Group III	Group IV	Group V	Total
Female	19	23	24	21	17	104
Male	15	10	10	14	17	66

Region of Enrollment
Region of Enrollment(participants)	Group I	Group II	Group III	Group IV	Group V	Total
Sudan	34	33	34	35	34	170

Study locations

1 site

University of Khartoum, Faculty of Dentistry,
Khartoum, 111-11, Sudan

References and documents

Publications

Owatz CB, Khan AA, Schindler WG, Schwartz SA, Keiser K, Hargreaves KM. The incidence of mechanical allodynia in patients with irreversible pulpitis. J Endod. 2007 May;33(5):552-6. doi: 10.1016/j.joen.2007.01.023. Epub 2007 Mar 6. PubMed 17437870 ↗
Albashaireh ZS, Alnegrish AS. Postobturation pain after single- and multiple-visit endodontic therapy. A prospective study. J Dent. 1998 Mar;26(3):227-32. doi: 10.1016/s0300-5712(97)00006-7. PubMed 9594474 ↗
Attar S, Bowles WR, Baisden MK, Hodges JS, McClanahan SB. Evaluation of pretreatment analgesia and endodontic treatment for postoperative endodontic pain. J Endod. 2008 Jun;34(6):652-5. doi: 10.1016/j.joen.2008.02.017. Epub 2008 Apr 2. PubMed 18498882 ↗
Mehlisch DR. The efficacy of combination analgesic therapy in relieving dental pain. J Am Dent Assoc. 2002 Jul;133(7):861-71. doi: 10.14219/jada.archive.2002.0300. PubMed 12148679 ↗
Breivik EK, Barkvoll P, Skovlund E. Combining diclofenac with acetaminophen or acetaminophen-codeine after oral surgery: a randomized, double-blind single-dose study. Clin Pharmacol Ther. 1999 Dec;66(6):625-35. doi: 10.1053/cp.1999.v66.103629001. PubMed 10613619 ↗
Keiser K, Hargreaves K.Building effective strategies for the management of endodontic pain. Endodontic Topics, Volume 3, Issue 1, pages 93-105, November 2002
Menhinick KA, Gutmann JL, Regan JD, Taylor SE, Buschang PH. The efficacy of pain control following nonsurgical root canal treatment using ibuprofen or a combination of ibuprofen and acetaminophen in a randomized, double-blind, placebo-controlled study. Int Endod J. 2004 Aug;37(8):531-41. doi: 10.1111/j.1365-2591.2004.00836.x. PubMed 15230906 ↗
Elzaki WM, Abubakr NH, Ziada HM, Ibrahim YE. Double-blind Randomized Placebo-controlled Clinical Trial of Efficiency of Nonsteroidal Anti-inflammatory Drugs in the Control of Post-endodontic Pain. J Endod. 2016 Jun;42(6):835-42. doi: 10.1016/j.joen.2016.02.014. Epub 2016 Apr 12. PubMed 27080115 ↗

Individual participant data

Plan to share: No — Not shared

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Aug 10, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT02417337
Lead sponsor: University of Khartoum
Responsible party: Dr. Wail Elzaki (Lecturer at Faculty of Dentistry, University of Khartoum) — Principal investigator
First posted: Apr 15, 2015
Start date: Aug 2012
Primary completion: Aug 2014
Completion: Jan 2015
Results posted: Jun 25, 2026
Last update: Aug 10, 2026

Study contacts

Neamat Abubakr, BDS,MDSc,PhD

study director · Faculty of Dentistry, University of Khartoum

Oversight

Data monitoring committee: No

View the source record on ClinicalTrials.gov ↗

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Studies of the drug tested here: Acetaminophen

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Efficacy of Different Drugs to Control Post Root Canal Treatment Pain

Study summary

Conditions studied

Browse trials for

In context

Pain, Postoperative Reclassified

Lead sponsor

Who can participate

✓Inclusion criteria

✕Exclusion criteria

Study design

Study arms

Interventions

What researchers measure

Primary outcomes

Secondary outcomes

Results

Participant flow

Outcome measures

Adverse events

Baseline characteristics

Study locations

References and documents

Publications

Individual participant data

Updates

Registry details

Key details

Study contacts

Oversight

Not currently enrolling

Follow this study

Discussion

Other studies in this condition

Other studies from this sponsor

Inclusion criteria

Exclusion criteria