Impact of Clinician Experience on Intraosseous Anesthesia Outcomes in Endodontic Treatment: Retrospective Cohort Study.

: Although many studies have demonstrated the effectiveness of intraosseous anesthesia (IOA), the experience of clinicians administering IOA has rarely been reported. Some endodontists may never have received formal training in IOA, raising questions about whether inexperienced clinicians can achieve similar results. Although the previous studies suggest that limited experience may increase the risk of complications, the extent to which clinician experience influences IOA outcomes remains uncertain. This study sought to assess whether clinician experience affects the effectiveness, patient comfort, and safety of IOA in endodontic treatment. : This retrospective cohort study included 72 patients who had previously undergone endodontic treatment or retreatment for mandibular molars. Of these, 37 were treated by an endodontic resident with limited IOA experience, and 35 by an endodontist with extensive IOA experience. IOA was administered using the QuickSleeper 5 system (Dental Hi Tec, Cholet Cedex, France) as the sole anesthetic technique before the start of the endodontic treatment or retreatment. Pain assessments were recorded preoperatively (baseline), during IOA administration, and during the treatment. Statistical analyses included binomial and chi-square tests to compare the success rates and associations between the clinician experience and the IOA outcomes. Statistical significance was set at < 0.05. : Pain during IOA administration was reported as none or mild in 98.6% of the patients, with no significant difference between the endodontist (97.2%) and resident (100%) groups ( = 0.378). Profound anesthesia was achieved in 94.1% of the cases, with no significant difference between the endodontist (96.8%) and resident (91.9%) groups ( = 0.738). Complications were rare, with two cases of perforator separation (5.4%) in the resident group; nevertheless, clinician experience was not significantly associated with complications ( = 0.553). Conclusions: Within the limitations of this study, clinician experience did not significantly affect the IOA outcomes, including effectiveness, patient comfort, and safety. These findings suggest that IOA can be used effectively by clinicians with different levels of experience, thus supporting its broader implementation in endodontic practice.