The purpose of my study is to test the effect of using piezosurgery and dexamethasone injection in the surgical extraction of impacted mandibular third molars, on Postoperative Pain.

Background: Third molar surgery is the most common procedure performed in oral and maxillofacial surgery practice.

This procedure is always associated with varying degrees of postoperative pain and swelling that may have a social impact. Traditionally, rotating instruments like burs have been used for osseous surgery.

Piezosurgery is a novel technique introduced to overcome the disadvantages associated with the conventional rotatory technique. Corticosteroids administration before or after the extraction of third molars is an efficient way to minimize postoperative pain due to their strong anti-inflammatory activity.

Many researchers conducted studies comparing the piezosurgery technique with conventional rotatory technique, regarding postoperative pain and working time, or studies comparing the conventional method with or without dexamethasone injection. Only one recent study (Nov 2018), conducted by Gümrükçü Z. et al. has compared Piezosurgery and dexamethasone injection in third molar surgery, but without evaluating the combined effect of these two techniques on postoperative pain.

Objectives: The objective of this study is to assess the effects of piezosurgery technique and intramuscular dexamethasone injection on postoperative pain in impacted third molar surgery.

Methods: The study design is a randomized controlled clinical trial: 80 patients with mandibular third molar impaction, indicated for surgical extraction should be treated randomly using either the piezosurgery or the conventional rotatory technique, and with or without intramuscular dexamethasone injection. Postoperative pain will be assessed using a visual analog scale (VAS) on days 1, 3, and seven postoperatively.

The differences in Post-operative pain within and between study groups (4 groups) will be tested using repeated measures of analysis of variance (ANOVA) or Friedman tests. Differences in working time among the three techniques will be assessed using a repeated measure of ANOVA. All statistical tests will be two-sided, and the significant level will be set at 0.05. All the analysis will be conducted using the Statistical Package for Social Sciences (SPSS) software version 22.

Inclusion Criteria:

• Age from 15 to 30 years,
• Having mandibular impacted third molars,

Exclusion Criteria:

• Heavy smokers (≥20 cigarettes),
• Uncontrolled systemic conditions,
• Infection of the surgery site,
• Psychological problems,
• History of allergy to dexamethasone, amoxicillin, or acetaminophen.