The present study aims to evaluate the effect of computer-controlled Starpen automatic injection device versus the traditional syringe on pain perception during Injection of nerve block anesthesia and extraction of mandibular primary molars.

Pain is "An unpleasant sensory and emotional experience connected to actual or potential tissue damage or described in terms of such damage". According to the American Academy of Pediatric Dentistry, a patient may experience serious physical and psychological complications from improper pain management.

Anxiety, a fear of dental procedures, is often linked to unpleasant stimuli such as needle phobia, high vibration, noises, pain, and the smell of materials or medications. Patients who experience anxiety often exhibit complex behavior before or during dental procedures, causing additional discomfort.

In most dental procedures, Local anesthetic (LA) is crucial to alleviate pain during dental procedures enabling the dentist to complete the process. Even though LA is used to reduce pain during the procedure, but traditional methods itself can cause pain, making pediatric patients anxious and uncooperative in dental offices.

Effective pain management is crucial for children receiving dental injections to promote comfort, cooperation, and compliance. These techniques include topical analgesics, distraction, injection rates, buffering and warming the local anesthesia, speed reduction, fine needles, and precooling. Yet, no conclusive painless injection technique has been developed yet.

Finally, The Wand system, developed in 1997 by Milestone Scientific Inc., it was the first Computer-Controlled Local Anesthesia Delivery (CCLAD)discovered. Other devices like Morpheus, Calaject, Quicksleeper, and Smartject have entered the market, these systems varying in injection speed, design, weight, and shape, so, dentists can select the one that best meets their requirements.

This device's main concept is that a local anesthetic injection is done by lowering the pressure and flow rate.

The CCLAD reduced destructive behaviors in young children who were difficult to cooperate compared to the traditional method and created a positive experience for both the patient and physician.

The main advantage of these CCLADS devices is The ability to provide a small quantity of the local anesthetic solution with a stable injection mode, which decreases the discomfort associated with less controlled injections. In both adult and pediatric dentistry, the CCLADS devices have proven effective for extractions, pulpal therapies, and restorations. Patients also tolerate them well and behave less disruptively.

The Traditional injection syringe compared with computer-controlled local analgesic delivery devices (CCLAD) regarding disruptive behavior, pain, anxiety, and biochemical parameters. The results showed lower VAS, WBS, and salivary cortisol values in CCLADS patients compared to the traditional syringe group. They concluded that a positive impact of CCLADS on pain and anxiety can be recommended for pediatric patients.

Using CCLADs is significantly less painful than using traditional syringes and opens new, promising opportunities for working with patients presenting high dental fear.

The Starpen is one of the most recent advances that is promoted as a more comfortable and painless alternative to the traditional local anesthetic syringe. It includes a power adapter, cartridge holder, handpiece, and charging base. In dental uses, it can be injected intramuscularly or subcutaneously. It comes in three different speeds-high, low, and hybrid-and two aspiration modes-manual and auto. It may be used with the majority of the conventional gauge needles.

Inclusion Criteria:

• Children aged 6-8 years
• Cooperative children (Rating 3 or 4 based on the Frankl behavior scale)
• Medically fit children (ASA I).
• Children are mentally capable of communication.
• First dental visit.
• Patient requiring extraction of lower primary molars due to root caries, crown fractures, periapical disease, and failed pulpotomies.

Exclusion Criteria:

• Children with a behavioral management problem.
• Parental refusal of participation.
• Children with a previous history of local anesthesia injection.
• Medically unfit children (other than ASA I).
• Uncooperative children (other than Frankl 3,4).
• Children under medications (antibiotics and analgesics) for the previous 48 hours that could alter the pain perception.
• Teeth that showed any signs of mobility, ankylosis, or root resorption affecting more than one-third of the root