Influence of root length on the success of buccal infiltration anesthesia using 4% articaine in maxillary first molars with irreversible pulpitis undergoing root canal treatment: a clinical study

INTRODUCTION. Buccal infiltration using 4% articaine with epinephrine is a widely preferred anesthetic technique for maxillary molars. However, failures in achieving profound pulpal anesthesia, especially in teeth with irreversible pulpitis, remain clinically challenging. Anatomical factors such as root length may influence anesthetic diffusion but are seldom investigated.

AIM. To evaluate the effect of root length on the success rate of buccal infiltration anesthesia in maxillary first molars diagnosed with irreversible pulpitis.

MATERIALS AND METHODS. A prospective single-arm clinical trial was conducted on 60 adult patients with irreversible pulpitis in maxillary first molars. Following buccal infiltration with 1.7 ml of 4% articaine containing 1:100,000 epinephrine, pain responses during dentin removal, pulp chamber access, and canal instrumentation were recorded using the Heft-Parker Visual Analog Scale. Root lengths were measured radiographically using a standardized endodontic protocol. Anesthetic success was defined as no or mild pain at any procedural stage.

RESULTS. Overall anesthetic success was 81.1%. Success rates by root were: mesiobuccal 83.3%, distobuccal 81.7%, and palatal 78.3%. Mean root lengths were 18.8 ± 1.5 mm (mesiobuccal), 19.1 ± 1.5 mm (distobuccal), and 20.6 ± 1.7 mm (palatal). No statistically significant correlation was found between increased root length and anesthetic failure (p > 0.05).

CONCLUSIONS. The variations in the lengths of different roots of maxillary first molars do not significantly affect the success rate of buccal infiltration anesthesia in cases of irreversible pulpitis.

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