Subjects eligible for study inclusion had an edentulous area in the mandible or maxilla and underwent a dental implant surgery. Subjects were excluded from study enrollment if they had systemic diseases which affect bone metabolism, history of allergy to amoxicillin, refused study enrollment or failed to return for follow-up.~Subjects were randomly divided into three groups : In group 1, subjects received prophylactic antibiotic orally (Amoxicillin 2mg ,1 hour before surgery) and post-surgical antibiotic (Amoxicillin 500 mg , q8h for five days), subjects received only prophylactic antibiotic (Amoxicillin 2mg ,1 hour before surgery) in group 2 ,and in group 3, subjects received post-surgical antibiotic (Amoxicillin 500 mg , q8h for five days) . An independent researcher made random allocation cards using computer-generated random. Then, allocated cases were placed in a sealed envelope. All subjects used 0.2% chlorhexidine mouthwash in the treatment period. All implants were placed with a two-stage protocol.~All subjects were followed up for 3 months to assess any infection signs and symptoms. Infection was diagnosed based on clinical findings such as pain, redness of the area, and discharge around the fixture.An independent dentist who was blind the study groups, evaluated all subjects.
Subjects who underwent a dental implant surgery were studied.Subjects randomly were aligned into three groups:In group 1, subjects received prophylactic antibiotic orally (Amoxicillin 2mg ,1 hour before surgery) and post-surgical antibiotic (Amoxicillin 500 mg , q8h for five days), subjects received only prophylactic antibiotic (Amoxicillin 2mg ,1 hour before surgery) in group 2 ,and in group 3, subjects received post-surgical antibiotic (Amoxicillin 500 mg , q8h for five days). The sign and symptom of infection were studied and the incidence of infection in each group was determined.