This study evaluated the outcomes in the post-operative recovery following dental implant surgery in patients who continued on oral anticoagulated therapy (OAT) with warfarin. The primary outcome of this study was to evaluate bleeding within the first 5 days post-surgery and presence of intraoral/extraoral hematomas in skin and mucosa oral.

The aim of this study was compare: 1) the frequency of immediate and short term postoperative bleeding using tranexamic acid (TXAg), bismuth subgallate (BSg) or dry gauze (DGg) as local hemostatic 2) explore the relation between bleeding and the occurrence of hematomas, with length of incision, duration of surgery, and alveolar ridge recontouring. 80 surgical procedures performed in a total of 71 patients (20 surgical procedures in 18 patients not on OAT and 60 surgical procedures performed in 53 patients on OAT) that were assigned to one of four groups, so that each group included 20 procedures. The control group (Cg) comprised 20 procedures performed in patients not on OAT. The 60 procedures to be performed in patients on OAT were randomly to one of the three following experimental groups: 1) TXAg group, OAT plus TXA as local hemostatic agent; 2) BSg group, OAT plus BS as local hemostatic agent; 3) DGg group, OAT plus compression with dry gauze as local hemostatic agent. Outcomes variables were:

Intraoperative variables: length of incision expressed (Li) alveolar ridge recontouring (Arr), total duration of surgery (Ds), surgical quadrant and implant location.

Postoperative variables: immediate postoperative bleeding (within the first 30 minutes after surgery), short-term bleeding: within the first 5 days post-surgery, determined according to the index described by Bacci, presence of intraoral/extraoral hematomas in skin or mucosa. Descriptive statistical, analysis of variance and regression logistic analysis was performed. Statistical significance was set at a value of p<0.05.

Inclusion Criteria:

Subjects:

• Systemically healthy.
• Healthy periodontal tissues or well-controlled periodontal health.
• In need of a maximum of two dental implants per hemiarcade,
• Showing ≥8mm bone height and ≥6 horizontal bone width.
• Needing a maximum of two surgical procedures.
• Who had written consent from the referring service to undergo the surgical procedure.

Exclusion Criteria:

Subjects:

• Requiring implant placement immediately after extraction.
• Systemic disease contraindicating implant surgery.
• Mental disability preventing them from complying with the protocol.
• Hematological, metabolic, autoimmune or bone diseases.
• Hepatic alterations or receiving medication affecting liver function.
• Receiving corticoid therapy, chemotherapy, or anticoagulant therapy within 10 days prior to the surgery.
• Taking antibiotics that interact with oral anticoagulants.
• Requiring vertical or periosteal incisions.
• Requiring bone regeneration strategy.

When treatment involved placing an implant in more than one hemiarcade, the corresponding surgeries were scheduled 30 days apart.

The participants on OAT allocated to one of the three different local hemostatic strategies, were not informed wich agent was used. Time of compression was equal in all groups.