Investigating the effect of post-operative antibiotic administration on the complications of impacted and semi-impacted mandibular third molar surgery - a double-blinded randomized clinical trial

This study examines the effect of prophylactic amoxicillin on complications during the extraction of mandibular third molars with various anatomical variations. It also seeks to understand the use of antibiotics in this surgery and to create a protocol for standardizing their prescription.

This is a Phase 2/3 randomized, double-blind, controlled trial with parallel groups involving 260 patients. The randomization method was Block randomization with blocks of 4 which used dice rolling for their arrangement.

Patients are classified into Pell & Gregory classification categories (B2 to C3) before surgery. Maximum mouth opening and soft tissue length are measured, and surgery is performed using the buccal approach after chlorhexidine rinse. Post-surgery, patients are randomly assigned to receive either 500 mg amoxicillin or placebo. They are assessed on days three and seven for mouth opening, soft tissue length, and any pus or discharge. To ensure blinding, medication or placebo is provided to patients confidentially, a third party is used to allocate the package to ensure the surgeon's blindness.

Samples are non-randomly selected from patients at Isfahan Dental School and the Special Clinic. Inclusion criteria are healthy individuals aged 16 to 35 with impacted or partially impacted mandibular wisdom teeth. Exclusion criteria include poor oral hygiene, ongoing antibiotic use, systemic diseases, and allergies to antibiotics, anti-inflammatories, or chlorhexidine mouthwash.

The intervention group is instructed to take 15 capsules of 500 mg amoxicillin, one every 8 hours for 5 days post-surgery. The control group will receive placebo capsules following the same schedule.

Maximum mouth opening, surgical site infection, length of soft tissue from tragus to menton.

In this study, to balance the samples between the intervention and control groups, and considering the sample size in each of the confounding categories C3, C2, C1, B3, B2, the block randomization method is used for randomization. Accordingly, 13 blocks of 4 individuals are used for each of the mentioned categories. These 4-person blocks can be arranged in 6 different ways: (IICC, ICIC, ICCI, CIIC, CICI, CCII)*. Each of these arrangements is assigned a number from 1 to 6, and the sequence of 13 blocks in each category is determined by rolling a dice. Based on this, participants are assigned to either the intervention or control group. For instance, the following block sequence, determined by dice rolls, is one possible arrangement that can be used for randomization in categories C3, C2, C1, B3, B2: ICCI, ICIC, CCII, IICC, ICIC, CCII, CICI, CCII, CIIC, IICC, CCII, ICCI, ICIC Thus, in each of the confounding categories C3, C2, C1, B3, B2, 26 participants will be in the intervention group and 26 in the control group, resulting in a total of 130 samples in each of the overall control and intervention groups. The block sequences for each category (C3, C2, C1, B3, B2) and in general will be determined by a third party (other than the patient and the treating surgeon) as described. Accordingly, the patient will receive either a placebo or the medication. Neither the patient nor the surgeon will be informed about the block arrangement. *I = Intervention, C = Control

In this double-blind clinical trial, patients are enrolled after meeting the specified criteria. Then, based on the tooth in question, the patient is classified by the surgeon into one of the C3, C2, C1, B3, B2 categories according to the Pell & Gregory classification, using an OPG image and clinical examination. Before surgery, and during the initial evaluation, the criteria for maximum mouth opening and the length of the patient's soft tissue are assessed by the surgeon, and their status is recorded in the relevant forms. After surgery, patients from each of the C3, C2, C1, B3, B2 categories are randomly divided into the intervention and control groups by a third party using the block randomization method. Both groups are given similar packages (sealed container 49x58 with a sealed lid) containing 15 capsules. The capsules contain 500 mg of amoxicillin for the intervention group, and a similar placebo for the control group(blinding the patient by prescribing a similar capsule containing pharmaceutical grade starch placebo). Both the intervention and control groups are evaluated on the third and seventh days after surgery during follow-up sessions by a surgeon who is unaware of the substance the patient consumed(blinding of the clinical caregiver due to the presence of a third party and allocation of packages to patients by him). The evaluation includes the measurement of maximum mouth opening, following the same protocol as the initial evaluation. The length of the patient's soft tissue is also re-measured and recorded using the aforementioned method. Finally, any discharge of pus or serous fluid from the surgical site is examined and documented during these follow-up sessions through clinical examination.

Information regarding the three main outcomes, namely surgical site infection, maximum mouth opening, and the length of the soft tissue from the tragus to menton, can be shared via a comprehensive Excel file after anonymizing the individuals.

The access period starts three months after the completion of the study writing and the publication of the results.

Researchers employed at academic and scientific institutions

Only researchers employed at academic and scientific institutions, whose job positions have been verified, can access the data tables for further analysis or aggregation with data from other studies after obtaining an ethics code from a reputable institution. The use of these documents is only permissible for examining the complications of impacted or semi-impacted mandibular third molar surgery.

To access the documents, applicants must contact the responsible individuals through one of the following methods: Phone number: 09035146324 - Mr. Ali Behnam Email 1: a.behnam1389@gmail.com - Mr. Ali Behnam Email 2: mahdi.2313@gmail.com - Dr. Mehdi Sadeghi

Applicants must send their request via email along with their job qualification documents and the ethics code related to their research. If both components are approved on the relevant websites, the data file will be sent to them via email within two weeks in accordance with the above-mentioned (in the first field) principles.