Sir, I write this letter to raise awareness of a rare complication involving local anaesthetic that presented in our maxillofacial department.

On the 3 October 2014 a 44-year-old female, with a medical history of glaucoma and gastric reflux, attended her regular dental practice to have an extraction of the maxillary second premolar on the right side under local anaesthetic and intra-venous sedation in what was believed to be a routine procedure. In total, 0.5 ml of lidocaine 2% with adrenaline 1:80,000 was administered as a palatal infiltration and 1.7 ml of the same anaesthetic injected as a buccal infiltration. The treatment was uneventful and the patient was sent home with post-operative instructions. Later that evening, the patient developed a blister in the region of the palatal infiltration site.

The patient visited the dentist for an emergency appointment the following day and was prescribed 500 mg amoxicillin tablets for 5 days and her clinical symptoms were monitored for two weeks. With no improvement, and the blister transitioning into an ulcer-like lesion of approximately 20 mm by 12 mm, the patient was urgently referred to Basildon Hospital's maxillofacial department on the 28 October 2014.

The patient was seen and diagnosed with palatal mucosal necrosis (Fig. 1) which would be managed conservatively with regular review appointments. A further two appointments were arranged for the patient on the 9 December 2014 and 15 January 2015, which highlighted healing of the ulcer and the presence of an erythematous area which was initially 20 mm by 20 mm and decreased to a size that was insignificant. However, the patient was experiencing severe post-traumatic neuralgia which developed at the site of the ulcer during the healing process and was prescribed 10 mg nortriptyline. The patient reported that the whole experience had left her stressed, affecting her personal and social life and has been advised to have counselling to treat this matter.

Figure 1
figure 1

Palatal mucosal necrosis

Full size image

The palate has a rich blood supply via the greater and lesser palatal arteries which will play a role in wound healing and sustaining metabolism by providing oxygen and nutrients.

An increase in pressure may provide an explanation into the aetiology of such an event, or the absence of a good supply, via vasoconstriction, deprives the tissue of its necessary sustenance resulting in necrosis of the overlying epithelium. The contraction of smooth muscle within the arterial wall during vasoconstriction may lead to transient ischemia of structures distally to the injection site leading to tissue necrosis.

If such symptoms do present under your care, a referral to the local maxillofacial department is justified for a second opinion. Regular reviews and reassurance is the treatment of choice, with photographs being an integral part of record keeping for medico-legal reasons.