Effects of Three Oral Analgesics on Postoperative Pain Following Root Canal Preparation: a Controlled Clinical Trial

Patients will be divided randomly into four groups of 25 patients each a control group receiving a single dose of a placebo (multivitamines) and three experimental groups receiving either a single dose of a Tramadol tablet (100 mg of Tramadol hydrochloride) Novafen capsules [325 mg of paracetamol (acetaminophen)], 200 mg of ibuprofen and 40 mg of caffeine anhydrous) or Naproxen tablets (500 mg of naproxen) immediately on completion of the first appointment. Balanced block random allocation will be made (12 blocks contained eight patients and one block contained four patients) by generating random digits via Microsoft Excel 2007. An Assistant who will be blinded to the aim and the protocol of the study generated the numbers. After explanation of the treatment procedures, treatment will be performed under rubber dam isolation by the dentist. The tooth will be anaesthetized using one cartridge of Ligocaine HCL 2%with Adenaline 0.001% injection 1.8ml (Septodont) local anaesthetic solution. If pain still remained during access cavity preparation, intrapulpal anaesthesia will be used as supplementary anaesthesia. The investigator who performed the root canal treatment will be blinded to the assignment. An access cavity will be prepared, and the working length will be determined electronically using an apex locator (Dentaport ZX; J. Morita, MFG,CORP) 1 mm short of the apex with a size 15 or 20 K-file and confirmed by periapical radiographs. The apical part of each root canal will be prepared to a size 25 K-file with the step- back technique in a circumferential manner. Normal saline (sodium chloride B.P0.9%W/V IV Infusion (sterifluid NS))will be used as the irrigant solution between each instrument. Canals will then be dried with paper points, and the access cavities will be restored temporarily with Cavit (3M ESPE, St Paul, MN, USA). Each patient's tablet/ capsule will be inserted into a sealed coded packet by a trained person who will be blinded to the drugs, and the packet remained sealed until it will be given to the patient. The patients will be supervised by one of the investigators when taking the oral medications. The intensity of the preoperative pain will then be measured by instructing the patient to complete a Visual Analogue Scale (VAS) before treatment and after 6, 12 and 24 h. At the second appointment, 24 h later the root canal treatment will be completed. The markings on the VAS will be measured, and the degree of pain will be categorized as mild (scores 1-3), moderate (scores 4-6) or severe (scores 7-10).