• Introduction: Effective pain control is critical in pediatric dentistry. The effectiveness of pain control in children can be influenced by child characteristics .

Objectives: The Purpose of the study is to compare the pain perception and the effectiveness of anesthesia between the computer-controlled local anesthetic delivery system (CCLAD) and the traditional inferior alveolar nerve block (IANB) in pulptomies of the mandibular second primary molars.

Materials and Methodology: The study sample includes 90 healthy children who are selected randomly from the R4 electronic filing system in King Abdulaziz University Hospital (KAUH) with age range from 5-9 years. The child is required local anesthesia for pulpotomies in the mandibular second molars. The sample will be divided randomly to one of these 3 groups: group A is composed of 30 patients who will be anesthetized by the traditional IANB. Group B includes 30 patients will be anesthetized by the IANB using CCLAD. While, the remaining 30 patients will be assigned in group C and will be anesthetized by periodontal ligament injection anesthesia using the CCLAD. The pain perception levels after the injection is assessed by a Wing-Baker faces pain scale. Effectiveness of the anesthesia during each step in pulpotomy is measured using Sounds, eyes and motor (SEM) scale. After the treatment by 24 hours parents will be contacted by the telephone to ask about the presence of postoperative pain or lip biting. Statistical analysis is carried out using SPSS version 16.00.

Ethical Consideration:

The Ethical Committee of King Abdulaziz University KAAUEC approved the study .

Subjects' selection:

The Sample includes children who are randomly selected by the R4 electronic file system in the pediatric dentistry specialty clinics at King Abdulaziz University Hospital (KAUH). A total of 2100 pediatric screening had been registered between April 2013 and November 2013 .These files will be checked for the eligible age in the study which is 5-9 years. Then, the inclusion and exclusion criteria will be checked, and the patients will be selected by systemic random sample.

Study design:

This is a randomized single blind clinical trial study.

The inclusion criteria:

1. Age of the children was ranged from 5-9 years.
2. Children were healthy physically and mentally; all children had no contraindications to local anesthesia.
3. Children were assessed as being cooperative, had behavioral ratings "positive" or "definitely positive" according to the Frankl (Frankl et al 1962) behavior classification scale (appendix1).
4. Children were diagnosed with carious mandibular second primary molars that required treatment with pulpotomies.

The exclusion criteria:

1. Disapproved consent.
2. Medically compromised children.
3. Uncooperative children.