Influence of patient position on the Success of Inferior Alveolar Block Anesthesia. A cross-sectional study in Al-mustansiriyah Dental School, Baghdad


Introduction: Despite the wide use of Inferior Alveolar Nerve Block anaesthesia indentistry it has a high percentage of failure (10 to 20%). This failure raterepresents a challenging clinical problem in the management of mandibular teeth.There have been several explanations for this problem. Some authors believe thatincorrect localization of the nerve near the mandibular foramen is the mainproblem with subsequent improper localization of the needle. Despite the attentionpaid to the different possible reasons for Inferior Alveolar Nerve Block, thepatient position and its influence on the operator's position and subsequently onthe success of the technique did not get enough attention.Aim of the study: To determine the influence of patient's position on the failure rateof Inferior Alveolar Nerve Block anaesthesia.Materials and Methods: Patients attended Oral Surgery Department, College ofDentistry, Almustansiria University in Baghdad for dental extraction wereincluded in this study. Dental extraction procedures were performed by 4th and5th class students. Inclusion criterion for the students was: students who performthe anaesthetic injection technique without the help of the supervising staffmember.Results: Fifty seven students were included in this study, 21(36.8%) were males and36 (63.2%) were females. Fifty seven students performed the local anaesthesia.Twenty four students were from 4th year (42.1%), and thirty three (57.9%) from5th year.Chi-Square Test showed highly significant relationship between patient's position andthe success of Inferior Alveolar Nerve Block (p<0.01, df=1). Chi-Square Testshowed no significant relation (p>0.05, df=1) between the success level ofanaesthesia and the student's year.Conclusion: Patient position is one of the factors that could influence the success ofIANB anaesthesia. Considerable deviation from the accurate chair angulation canincrease the chance of failure of IANB.