Influence of patient position on the Success of Inferior Alveolar Block Anesthesia

Abstract

Introduction: Despite the wide use of Inferior Alveolar Nerve Block anaesthesia in
dentistry it has a high percentage of failure (10 to 20%). This failure rate
represents a challenging clinical problem in the management of mandibular teeth.
There have been several explanations for this problem. Some authors believe that
incorrect localization of the nerve near the mandibular foramen is the main
problem with subsequent improper localization of the needle. Despite the attention
paid to the different possible reasons for Inferior Alveolar Nerve Block, the
patient position and its influence on the operator's position and subsequently on
the success of the technique did not get enough attention.
Aim of the study: To determine the influence of patient's position on the failure rate
of Inferior Alveolar Nerve Block anaesthesia.
Materials and Methods: Patients attended Oral Surgery Department, College of
Dentistry, Almustansiria University in Baghdad for dental extraction were
included in this study. Dental extraction procedures were performed by 4th and
5th class students. Inclusion criterion for the students was: students who perform
the anaesthetic injection technique without the help of the supervising staff
member.
Results: Fifty seven students were included in this study, 21(36.8%) were males and
36 (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%) from
5th year.
Chi-Square Test showed highly significant relationship between patient's position and
the success of Inferior Alveolar Nerve Block (p<0.01, df=1). Chi-Square Test
showed no significant relation (p>0.05, df=1) between the success level of
anaesthesia and the student's year.
Conclusion: Patient position is one of the factors that could influence the success of
IANB anaesthesia. Considerable deviation from the accurate chair angulation can
increase the chance of failure of IANB.