A Survey of Pain Levels Reported at Different Injections Stages

Objective: Several measures commonly undertaken to reduce the discomfort of dental injections include: topical anaesthesia, warming of solution, and slow deposition of solution. If these have any effect, this will occur at different points during the sequence of injection. The aim of this study was to clarify how much pain is elicited during various phases of an intraoral injection, in order to allow evaluation of the potential benefit of such manoeuvres. Method: 141 injections were given as a part of normal undergraduate dental treatment. The injection sequence was divided notionally into three stages. First: the puncture of the needle tip through the mucosa. Second: the penetration of the needle through the looser tissues below, to reach the site of solution deposition. Third: deposition of the solution. The operator indicated verbally the duration of each stage. Immediately following injection the subject completed three visual analogue scales, corresponding to the three stages of injection. The site, type and success of each injection was recorded. Result: Different levels of pain were reported by subjects during the different injection stages. The insertion stage was reported as more painful. During inferior dental block injections, this difference was statistically significant. Conclusion: Reported pain varies as the process of injection progresses. We suggest there is an anatomical basis for this.