Eighty patients will be requested to take participate in this study after signing a written consent form. The inclusion criteria for the participants are as follows: 18-65 years old, having no systemic disease, not pregnant or beast feeding, having a mandibular premolar/molar or a maxillary anterior tooth with the diagnosis of normal pulp, reversible pulpitis or asymptomatic irreversible pulpitis (no or mild tenderness to percussion, normal periapical radiographic appearance), not taking analgesics, sedative or anti-anxiety medication and no intra oral injection at the treatment area, during the last 24 hours. By using a 170 mm Visual Analogue Scale (VAS), patients with pain less than or equal to 54 are classified as having asymptomatic irreversible pulpitis. The way to use the VAS will be explained to the patients prior to the procedure.~Each patient will receive an injection in one of the following groups according to the random number table:~Group TPMB: Topical pressure and massage with an Inferior alveolar nerve block (IANB)~Group TGB: Topical gel of 20% Benzocain (Master-Dent, Monroe, NC) with IANB~Group TPMI: Topical pressure and massage with a maxillary anterior infiltration (MAI)~Group TGI: Topical gel with a MAI~All the injections will be performed using an aspirating syringes containing 1.8 ml of lidocaine with 1:80000 epinephrine (2%Persocaine_E; Darupakhsh, Tehran, Iran) and 28-guage needles by a single operator (N.M.A). Immediately after the injection, patients will be asked to record the amount of pain they felt during needle penetration and injection using VAS form. If the patient is subjected to more than one injection during the root canal treatment, only the first injection will be subjected to the evaluation. Recording of the acquired data from the VAS forms will be done by another operator (P.M) who will be unaware of the patients' categorization.~Data will be analyzed using ANOVA and t-test with the significance level of p<0.05.
Eighty patients with inclusion criteria will participate in this studyEach patient will receive an injection in one of the following groups according to the random number table:~Group TPMB: Topical pressure and massage with an Inferior alveolar nerve block (IANB)~Group TGB: Topical gel of 20% Benzocain (Master-Dent, Monroe, NC) with IANB~Group TPMI: Topical pressure and massage with a maxillary anterior infiltration (MAI)~Group TGI: Topical gel with a MAI. Immediately after the injection, patients will be asked to record the amount of pain they felt during needle penetration and injection using VAS form.Data will be analyzed using ANOVA and t-test.