The study will be conducted to evaluate instrumentation time, obturation quality, and child's behavior using pediatric rotary versus hand flare file systems in treatment of primary molars.

Statement of the problem:

Pulpally affected primary teeth is a common problem in children due to lower mineralization, the presence of large pulp chamber with high pulp horns, and thin layers of enamel and dentin .

Manual files system is usually used for management of pulpally affected primary molars. This system has shown through the past years an acceptable clinical success rate but it also have many problems such as long visit time affecting the child behavior and causing fatigue to the dentist, difficulty in dealing with thin and curved canals due to limited flexibility of manual files causing incomplete removal of pulp tissue, and also difficulty in the determination of the actual working length due to the presence of physiologic and pathologic root resorption.

Rationale for conducting the research:

Pulp therapy in primary molars becomes compromised sometimes after delayed treatment due to dental neglect of children till caries progression to the pulp leading to severe symptoms associated with excessive pulp inflammation, root resorption, or periradicular bone resorption with a less favorable prognosis for conventional endodontic therapy. In the current era, a new perspective which is less time consuming with an acceptable success rate could be a spark of hope for the pediatric patient as well as the dentists.

Many studies were done comparing manual vs pediatric rotary files but without definitive conclusion. So further studies should be done with higher sample size to determine the superiority of one system over the other.

Benefits for the practitioner:

• Providing new and alternative treatment options.
• Shorter instrumentation time.
• Less fatigue.
• Better preparation of the canal.

Benefits for the patient:

• A faster and easier process leading to a more efficient dental procedure which could develop better outcomes in terms of success.
• Improvement in patient as well as parent satisfaction.

Benefits for community:

• Using alternative technique that can be faster, with a better success rate.
• To boost overall oral health.

Inclusion Criteria:

Children:

• Cooperative children.
• 4-6 years old children.
• Children who will attend follow up.

Teeth:

• Bilateral lower second primary molars.
• Pulpally involved molars indicated for pulpectomy.

Exclusion Criteria:

Children:

• Children with physical or emotional alteration.
• Children with systemic diseases.
• Children of parents who don't accept to participate in the study.

Teeth:

• Teeth with more than 1/3 of root resorption.
• Teeth with pathological mobility.
• Necrotic teeth with periapical or furcal lesions.
• Non restorable teeth.

Data may be provided upon request