Coronectomy of High Risk Wisdom Teeth With Superficial Caries: A Case Series With 12-Month Follow-up

The coronectomy procedure is a technique that reduces morbidity of the Inferior Alveolar Nerve (IAN) after removal of high-risk mandibular third molars. Although the incidence of nerve injury is reported as 0.2-2% permanent and 2-20% temporary,¹ the residual consequences to patients can be devastating. The success of coronectomy relies on the retained root fragment having vital, non-inflamed pulpal tissue and normal surrounding bone. Coronectomy in carious teeth therefore has been contraindicated.

The most common short-term complications following coronectomy are localised alveolar osteitis reported in 10-12% of cases and infection in 0.98-5.2% of cases.² Permanent IAN paraesthesia has not been reported following coronectomy. Long-term complications include delayed eruption of roots requiring a second procedure. The incidence of this varies from 0-6%.²

We present a case series of 17 patients with high risk, vital, carious wisdom teeth managed with coronectomy. All patients were treated at Guy’s Dental hospital, London from 2012-2015. A strict inclusion criteria was adopted to only include vital wisdom teeth with enamel or superficial dentine caries, displaying high-risk radiographic features. Patients were carefully consented and informed preoperatively that a coronectomy would only be performed on teeth with a healthy, bleeding pulp intraoperatively. A non-vital or hyperaemic pulp was an exclusion criteria, and these roots would therefore be removed.

These patients were followed up at 1 and 12 months. A thorough history was taken at the initial review to identify postoperative pain scores, time off work and the incidence of any postoperative complications. At each subsequent visit a clinical examination carried out to assess for primary mucosal closure and any signs of pathology, and a radiograph was taken to assess for pathology or root migration and bony infill around the retained.

All 17 patients attended their first review at one month postoperatively. Nine patients attended for a 12 -month follow up. The remaining 8 patients who failed to attend this appointment had a 1-year telephone review.

The mean recorded VAS score during week 1 postoperatively was 6/10 despite 76% of patients reporting analgesia taken was adequate for pain relief. The mean number of days taken off from work was 3. The incidence of postoperative complications was 47% (n=8). Alveolar osteitis accounted for the most frequent postoperative complication (14%). However, of these patients, 63% were treated for alveolar osteitis as well as being prescribed antibiotics (n=5), which suggests possible misdiagnosis of the postoperative complication.

Of the patients who attended for review at 12 months, 100% had radiographic evidence of bony infiltration, and there were no signs of pathology. All Patients contacted by telephone were completely asymptomatic. 1 patient was lost to follow up.

No patients required a second procedure at 12 months post-coronectomy and most importantly there were no temporary or permanent cases of paraesthesia reported.

 

The ideal treatment for carious wisdom teeth is extraction; however, high-risk carious wisdom teeth with vital pulp can be managed with a coronectomy, but with caution. It is important for patients to be aware of the risks and the need for long-term follow-up. This short case series shows some evidence towards coronectomy as a viable treatment option in high risk wisdom teeth with superficial caries but vital pulp, however, further cases with a longer-term follow-up are required.

References:

1. Gleeson CF, et al: Coronectomy practice paper. Technique and trouble shooting. British Journal of Oral and Maxillofacial Surgery, doi:10.1016/j.bjoms.2012.01.001, 2012
2. Patel V. et al: Coronectomy practice. Paper 2: complications and long-term management British Journal of Oral and Maxillofacial Surgery 51: (2013) 347–352, 2013