An observational study in Tooth Extraction, Postoperative Hemorrhage and Platelet Aggregation Inhibitors, sponsored by University of Medicine and Pharmacy at Ho Chi Minh City. Completed at 1 site in Vietnam. Open to participants aged 40 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-03.
Sponsored by University of Medicine and Pharmacy at Ho Chi Minh City · Observational
This prospective, assessor-blinded, controlled observational study compares bleeding after simple tooth extraction between adults aged 40 years or older who continue their antiplatelet therapy (aspirin, clopidogrel or dual antiplatelet therapy) without interruption and controls taking no drug that affects haemostasis. Socket bleeding is graded at 15, 30, 45 and 60 minutes within a stepwise local haemostatic protocol, and recurrent bleeding is monitored by telephone for 72 hours. The study also explores demographic, clinical and pharmacological factors associated with prolonged and recurrent bleeding among patients on antiplatelet therapy.
Patients receiving long-term antiplatelet therapy for cardiovascular or cerebrovascular disease increasingly require dental extractions. Guidelines recommend continuing antiplatelet therapy for low-bleeding-risk procedures, but prospective data from older Southeast Asian patients, among whom clopidogrel is widely prescribed, are lacking.
Consecutive eligible patients on uninterrupted antiplatelet therapy and controls frequency-matched for sex and tooth type are enrolled at the Department of Odonto-Stomatology, Ba Ria General Hospital, Vietnam. Before extraction, patients on antiplatelet therapy undergo a complete blood count, PT, INR and aPTT, and a cardiologist confirms that therapy should be continued. All simple extractions of one to three teeth are performed by one experienced oral surgeon under 2% lidocaine with 1:100,000 epinephrine (maximum two cartridges).
A blinded assessor grades socket bleeding as none, mild or severe at 15 (T1), 30 (T2), 45 (T3) and 60 (T4) minutes. Bleeding sockets are managed stepwise: gauze pressure until T2, a gelatin sponge at T2, and topical tranexamic acid with sutures at T3; persistent bleeding at T4 would prompt hospital observation. Recurrent bleeding after discharge is assessed by structured telephone interviews at 24, 48 and 72 hours. Groups are compared with Fisher's exact and Mann-Whitney U tests, and factors associated with prolonged and recurrent bleeding in the antiplatelet group are explored with Firth-penalised logistic regression.
135 studies on the registry are indexed under Postoperative Hemorrhage; 31 are open to participants now.
This study's enrollment of 210 is above the median of 100 across 29 observational studies indexed under Postoperative Hemorrhage.
Browse Postoperative Hemorrhage studies →University of Medicine and Pharmacy at Ho Chi Minh City is the lead sponsor of 127 studies on the registry; 44 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Adults aged 40 years or older with an indication for simple extraction of one to three teeth at the Department of Odonto-Stomatology, Ba Ria General Hospital, Vietnam: consecutive patients on uninterrupted antiplatelet therapy and controls taking no drug that affects haemostasis.
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.
Exclusion Criteria:
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.
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.
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.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Adults aged 40 years or older taking aspirin, clopidogrel or dual antiplatelet therapy without interruption during the 7 days before simple extraction of one to three teeth.
Drug: Antiplatelet therapy (uninterrupted) · Procedure: Simple tooth extraction with stepwise local haemostatic protocol
Adults aged 40 years or older taking no drug that affects haemostasis, recruited during the same period and frequency-matched to the APT group for sex and tooth type, undergoing simple extraction of one to three teeth.
Procedure: Simple tooth extraction with stepwise local haemostatic protocol
Aspirin 81 mg/day, clopidogrel 75 mg/day, or aspirin 100 mg plus clopidogrel 75 mg/day (dual antiplatelet therapy), continued without interruption as prescribed by the patient's physician. Antiplatelet therapy is not assigned by the investigators.
Also known as: Aspirin, Clopidogrel
Non-surgical extraction of one to three teeth by one experienced oral surgeon under 2% lidocaine with 1:100,000 epinephrine (maximum two cartridges), followed by gauze pressure; a gelatin sponge is placed at 30 minutes and topical tranexamic acid irrigation with sutures is applied at 45 minutes when bleeding persists.
Proportion of Sockets With Residual Bleeding at 15 Minutes
Socket bleeding is graded by a blinded assessor after gauze removal as none (no visible bleeding), mild (oozing without continuous flow) or severe (immediate, continuous flow). Residual bleeding is defined as mild or severe bleeding.
Time frame: 15 minutes after tooth extraction
Proportion of Sockets With Residual Bleeding at 30 Minutes
Same three-level grading (none, mild, severe) after continued gauze pressure. Residual bleeding is defined as mild or severe bleeding.
Time frame: 30 minutes after tooth extraction
Proportion of Sockets With Residual Bleeding at 45 and 60 Minutes
Same three-level grading after gelatin sponge placement (45 minutes) and after topical tranexamic acid irrigation with sutures (60 minutes).
Time frame: 45 and 60 minutes after tooth extraction
Time to Haemostasis
Time from tooth delivery to the first assessment at which no bleeding is observed, in minutes.
Time frame: Up to 60 minutes after tooth extraction
Most Advanced Local Haemostatic Measure Required
Proportion of visits managed with gauze pressure only, a gelatin sponge, or topical tranexamic acid with sutures.
Time frame: Up to 60 minutes after tooth extraction
Recurrent Bleeding After Discharge
Any bleeding reported after discharge once haemostasis had been achieved, assessed by structured telephone interviews at 24, 48 and 72 hours; timing and management are recorded.
Time frame: Up to 72 hours after tooth extraction
Factors Associated With Prolonged and Recurrent Bleeding in the Antiplatelet Therapy Group
Odds ratios from Firth-penalised logistic regression for age, sex, number of teeth extracted, extraction time, platelet count and antiplatelet regimen.
Time frame: 30 minutes and 72 hours after tooth extraction
Plan to share: Undecided — De-identified data are available from the corresponding author on reasonable request.
No publications or documents are linked to this record.
Ran from Sep 2024 to primary completion in Aug 2025, 11 months.
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 Oct 2026. You cannot join it, but the record below documents what was studied.
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