An interventional study of Placebo and Ibuprofen in Impacted Third Molar, Postoperative Pain and Neuroinflammation, sponsored by Plovdiv Medical University. Completed at 1 site in Bulgaria. Open to participants aged 18 Years to 38 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-07.
Sponsored by Plovdiv Medical University · Not applicable, Interventional, and Basic science
A prospective cohort of 40 consecutive patients with bilateral impacted mandibular third molars underwent two sequential surgical extractions separated by a two-week interval. Serum kynurenic acid (KYNA) and serotonin were measured preoperatively and 24 hours after each procedure. The study examined longitudinal dynamics of kynurenine pathway biomarkers, their variation across Pederson surgical difficulty grades, and their relationship with postoperative pain and state anxiety.
Participants were randomised to placebo, ibuprofen 400 mg, or ibuprofen 400 mg plus gabapentin 300 mg administered preemptively 1 hour before incision and continued at 8-hourly intervals for 24 hours. Blood samples were collected at four timepoints (T0 Op1, T24 Op1, T0 Op2, T24 Op2) and analysed by ELISA for serum KYNA and serotonin. Postoperative pain was assessed by VAS at 2, 6, 12, 24, 48, and 72 hours. State-trait anxiety was assessed using the STAI Form Y before each operation. Pederson difficulty index was applied independently by two calibrated examiners. The biomarker analysis is reported observationally with pharmacological allocation treated as a covariate. Clinical data and samples were collected at the Department of Oral Surgery, Faculty of Dental Medicine, Medical University of Plovdiv, Bulgaria, during 2017-2018; laboratory biomarker analyses were conducted under Project No. DPDT-12/2019, Medical University of Plovdiv, and completed in 2020.
5,640 studies on the registry are indexed under Pain, Postoperative; 1,230 are open to participants now.
This study's enrollment of 40 is below the median of 75 across 4,821 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →Plovdiv Medical University is the lead sponsor of 16 studies on the registry; 5 are open to participants now.
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A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Identical-appearing capsules administered 1 hour before incision, repeated every 8 hours for 24 hours. N=10.
Drug: Placebo
Ibuprofen 400 mg oral capsules administered 1 hour before incision, repeated every 8 hours for 24 hours. N=15
Drug: Ibuprofen
Ibuprofen 400 mg plus Gabapentin 300 mg oral capsules administered 1 hour before incision, repeated every 8 hours for 24 hours. N=15
Drug: Ibuprofen + Gabapentin
Identical-appearing oral capsules administered preemptively 1 hour before incision and every 8 hours for 24 hours.
Ibuprofen 400 mg oral capsules administered preemptively 1 hour before incision and every 8 hours for 24 hours.
Drug pages: Ibuprofen · Gabapentin
Ibuprofen 400 mg plus Gabapentin 300 mg oral capsules administered preemptively 1 hour before incision and every 8 hours for 24 hours.
Serum kynurenic acid (KYNA) concentration
Change in serum KYNA from preoperative baseline (T0) to 24 hours postoperative (T24) at each of two sequential operations, assessed by ELISA
Time frame: Preoperative baseline and 24 hours postoperative at each operation
Serum serotonin concentration
Change in serum serotonin from preoperative baseline (T0) to 24 hours postoperative (T24) at each of two sequential operations, assessed by ELISA
Time frame: Preoperative baseline and 24 hours postoperative at each operation
Postoperative pain intensity
Pain assessed using a 100 mm Visual Analogue Scale (VAS; 0 = no pain, 100 = worst imaginable pain)
Time frame: 3, 6, 24, 48, and 72 hours postoperatively at each operation
State anxiety
Preoperative state anxiety assessed using the State-Trait Anxiety Inventory (STAI Form Y), State subscale
Time frame: Preoperative baseline at each operation
KYNA variation across Pederson surgical difficulty grades
Serum KYNA at 24 hours postoperative compared across Pederson difficulty grades (5-9), assessed by Kruskal-Wallis test
Time frame: 24 hours postoperative at Operation 1
Plan to share: No — Individual participant data are not planned for public sharing. Anonymized data are available from the corresponding author on reasonable request.
No publications or documents are linked to this record.
Ran from Oct 2017 to primary completion in May 2020, 31 months.
Of 2,089 non-industry interventional studies with no phase under Pain, Postoperative, half reached primary completion within 11 months of starting (the median), counting those still running; a quarter within 6 and three quarters within 23. This study's 31 months is above that.
Counting every sponsor, half of 2,102 studies reached it within 11 months; a quarter within 6 and three quarters within 23.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drugs tested here: Ibuprofen · Gabapentin
Plovdiv Medical University