Injectable Diclofenac for the Prevention of Post-operative Dental Pain (DP4)

• Pain Intensity [ Time Frame: Pain will be scored every 15 minutes up to to 6 hours postsurgery. Pain will be assessed at home hourly up to 12 hours post-surgery and twice daily every day up to 1 week after surgery. ] [ Designated as safety issue: No ]
• Postsurgical extra-oral swelling [ Time Frame: measured at 6 hours postsurgery, at day 3 and 1 week postsurgery ] [ Designated as safety issue: No ]
• Trismus [ Time Frame: measured at 6 hours postsurgery, at day 3 and 1 week postsurgery ] [ Designated as safety issue: No ]
• Peak pain intensity [ Time Frame: measured from end of surgery up to 12 hours postsurgery ] [ Designated as safety issue: No ]
• Time to first use of rescue medication. [ Time Frame: measured from end of surgery up to 1 week postsurgery ] [ Designated as safety issue: No ]
• Amount of rescue medication [ Time Frame: consumed by the patient every 15-minutes postsurgery up to 6 hours postsurgery ] [ Designated as safety issue: No ]
• Rescue medication consumption [ Time Frame: consumed by the patient from end of surgery up to 24 and up to 48 hours postsurgery ] [ Designated as safety issue: No ]
• Patient and investigator global evaluation of the effectiveness of treatment [ Time Frame: at 6 hour postsurgery and on Day 3 ] [ Designated as safety issue: No ]
• time to onset of pain [ Time Frame: measured from end of surgery up to 12 hours postsurgery ] [ Designated as safety issue: No ]
• wound healing [ Time Frame: at 6 hour postsurgery, and on day 3 and 1 week postsurgery ] [ Designated as safety issue: Yes ]
• recurrent bleeding [ Time Frame: every hour up to 6 hour postsurgery ] [ Designated as safety issue: Yes ]
• Vital signs [ Time Frame: presurgery (within 30 days from surgery), at day of surgery (day 1), day 3 and 1 week postsurgery. ] [ Designated as safety issue: Yes ]
• Number of patients with Adverse Events [ Time Frame: from signature of the informed consent to 1 week postsurgery ] [ Designated as safety issue: Yes ]

This is a prospective, randomised, double-blind, placebo-controlled, parallel group study in approximately 75 patients undergoing surgical removal of an impacted lower third molar.

• Experimental: Diclofenac sodium 5 mg/mL
  Intervention: Drug: Diclofenac sodium
• Experimental: Diclofenac sodium 12.5 mg/mL
  Intervention: Drug: Diclofenac sodium
• Experimental: Diclofenac sodium 25 mg/mL
  Intervention: Drug: Diclofenac sodium
• Experimental: Diclofenac sodium 50 mg/mL
  Intervention: Drug: Diclofenac sodium
• Placebo Comparator: Placebo 1 mL
  Intervention: Drug: Diclofenac sodium

Inclusion Criteria:

1. Out-patients of either gender.
2. Patients aged ≥ 18 to ≤ 65 years old.
3. Subjects able and willing to give their written consent prior to inclusion in the study.
4. Female subjects of childbearing potential must (1) have a negative urine pregnancy test at the inclusion visit, (2) be using an appropriate method of contraception according to the definition of Note of ICH M3 Guideline (implants, injectables, combined oral contraceptives, some IUDs, sexual abstinence or vasectomised partner), and (3) be willing to continue using the contraceptive method throughout the entire study period.
5. Subjects must (1) be able to comprehend the full nature and purpose of the study, including possible risks and side effects, (2) fully co-operate with the Investigator, (3) comply with the requirements of the entire study.
6. Patients undergoing surgical extraction of a single, fully or partially impacted mandibular 3rd molar requiring bone removal.

Exclusion Criteria:

General

1. Patients refusing to give written informed consent.
2. Patients not able to understand the purposes of the study or not willing to return for the control visits.
3. Patients with major psychiatric disorders that, in the investigator's opinion, could compromise study participation.
4. Patients enrolled in any clinical trial in the previous 3 months.
5. Employees of the study centre with direct involvement in the proposed study or other studies under the direction of the main investigator or study centre, as well as family members of the employees or investigator.
6. Pregnant or breast-feeding women.
7. Alcohol or drug abuse in the previous 12 months.
8. Clinically significant or unstable concomitant disease whose sequelae might interfere with the study evaluation parameters.