Sir, the majority of reported cases of mandibular osteonecrosis and bone exposure have been associated with bisphosphonate use or radiation therapy. However, three publications in the BDJ have reported such findings in the posterior and medial aspect of the mandible not being associated with medication or radiation.1,2,3 We wish to present another interesting case.

A healthy, non-smoking and non-medicating 31-year-old Caucasian male underwent uncomplicated surgical removal of partially erupted mandibular third molars on both sides. Five weeks post-surgery, the patient presented with discomfort and moderate pain of two days duration from both sides of the posterior and medial aspect of the mandible. Examination revealed bilateral necrotic bone exposure on the medial bone shelves at the level of the removed third molars (Figs 1 and 2), each measuring approximately 2 × 2 mm. The surrounding mucosa was inflamed, but without sign of infection. Radiographic examination revealed no pathology. The patient was prescribed paracetamol for pain control and chlorhexidine oral rinse for the inflamed mucosa. The necrotic and exposed bone parts exfoliated spontaneously seven weeks post-surgery. Healing was confirmed eight weeks post-surgery.

Figure 1-2
figure 1

Bilateral necrotic bone exposure of the medial aspect of the mandible at the mylohyoid ridge

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Overall, mandibular tori and the posterior aspect of the medial shelf (at the level of the mylohyoid ridge) are two of the most common locations for osteonecrosis. Prior to surgery, it was noted that the patient had bilaterally prominent mandibular shelves. A standardised lateral approach was used on both sides and there was no perforation of the medial wall during the surgery. Hence, the osteonecrosis was likely secondary to bone remodelling post-surgery.

It is important for dental surgeons to be aware that osteonecrosis of the mandible is not always associated with medication or radiation but can occur in healthy patients. The local anatomy of the medial shelf needs to be examined prior to surgery in the posterior aspect of the mandible, and patients with prominent bone shelves should receive preoperative information that there is a small risk for delayed healing. As the complication described in the present case is rare, changing the surgical approach is not advised. However, a medial flap instead of a lateral could be considered in selected cases. This approach will allow the operator to smooth the bony shelf before wound closure.