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Investigating the Association between the Presence of Pulp Stone and Anesthesia Failure in Upper and Lower Molar
Masoud Parirokh1, Hamed Manochehrifar1, Nozar Nakahee2
1Endodontology Research Center, Kerman University of Medical Sciences, Kerman, Iran.
Introduction:
The close relationship between pulp stones in the pulp chamber and pulp neurovascular tissues suggests that the presence of pulp stones may compromise successful anesthesia. The present study assessed the effect of pulp stone presence on the failure of anesthesia in mandibular and maxillary molars.
Materials & Methods:
In this retrospective cohort study, 126 patients were studied. Pulp stones were diagnosed by periapical radiography. After the anesthetic agent injection, failure was defined as patients raising their hand upon experiencing pain during any procedural step of endodontic treatment. Furthermore, sound, eye, and motor (SEM) measures were used to assess the pain experience. In the case of either pain felt or the patients' demand, supplementary injections were made using the intraligamental technique. Multivariate logistic regression analysis was used to assess the effects of different variables on the success of anesthesia.
Results:
The overall prevalence of pulp stones in the patients was 59.5%, with 42.9% and 57.1% for males and females, respectively. The incidence of pulp stones in patients under the age of 40 was 54.7%, whereas in the ≥40 age group, it was 64.5%. The highest incidences of pulp stones were reported for maxillary second (42.9%) and first (21.4%) molars, followed by mandibular second (18.6%) and first molars (17.1%). Overall, the success rate of anesthesia was 55.6% for treated teeth. However, no significant differences were observed in the success rate of anesthesia regarding gender, tooth type, and pulp stone presence. Only the age group of patients significantly predicted the success of anesthesia (Odds ratio: 1.135; CI 95%: 1.43-6.76; P=0.004).
Conclusion:
Pulp stones had no significant effect on the success of anesthesia in mandibular and maxillary molars.
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