Predicting the choice of anaesthesia for third molar surgery - guideline or the easy-line?

To observe trends in choice of anaesthetic for mandibular third molar surgery in the Combined Department of Oral and Maxillofacial Surgery and Oral Medicine, based at the Edinburgh Dental Institute (EDI) and St John's Hospital (SJH) in Livingston.

Data were collected retrospectively from electronic patient records for 301 consecutive new referrals for mandibular third molar surgery from general dental practitioners to each of the oral and maxillofacial departments in the EDI and SJH from the 1 September 2009 onwards. Date of consultation, grade of assessing clinician, age, gender, postcode, required surgical procedure, choice of anaesthetic and predicted difficulty of procedure were analysed.

One hundred and fifty patients were seen at the EDI and 151 at SJH. There was no statistically significant difference in the proportion of male and female patients or age of patients presenting at each site. Seventeen patients (11.3%) were listed for a general anaesthetic, 21 (14%) for conscious intravenous sedation and 112 (74.7%) for local anaesthetic at EDI. At SJH 57 patients (37.7%) were listed for a general anaesthetic, 30 (19.9%) for conscious intravenous sedation and 64 (42.4%) for local anaesthetic. There was only a small difference in the difficulty of cases at the two sites, though there was a significant difference in socioeconomic deprivation between the two populations.

Significantly more general anaesthetics are being prescribed for mandibular third molar surgery at SJH than the EDI. This finding is not related to difficulty of the cases presenting at each site but may be related to the nature of a maxillofacial clinic compared to a dedicated oral surgery centre. The difference in socioeconomic deprivation may have had an impact on patient decisions.