Jerry Kwok

Coronectomy practice. Paper 2: complications and long term management

Coronectomy was developed to reduce the incidence of iatrogenic injury to the inferior dental nerve, which can be a result of routine mandibular third molar surgery, but it is not widely accepted despite early studies that all showed positive results. This two-part paper looks at the technique in more detail to help clinicians gain a better understanding of the procedure. The first part dealt in detail with technical aspects. This one will consider the management of common complications.

Coronectomy practice. Paper 1. Technique and trouble-shooting

Coronectomy is a technique that reduces morbidity of the nerve after operation on high-risk mandibular third molars. This two-part paper aims to give an overview of the technique and a description of common problems that can be encountered during and after operation. In this paper we discuss the technique as an overview and then each type of impaction more specifically. We also explore common problems encountered during the procedure and their subsequent management.

Histological evaluation of mandibular third molar roots retrieved after coronectomy

There is a resurgence of interest in coronectomy for the management of mandibular third molars because it has a low risk of injury to the inferior dental nerve. However, there is concern that the root that is left in place will eventually become a source of infection. We describe the histological evaluation of 26 consecutive symptomatic coronectomy roots in 21 patients. All roots had vital tissue in the pulp chamber and there was no evidence of periradicular inflammation. Persistent postoperative symptoms related predominantly to inflammation of the soft tissue, which was caused by partially erupted roots or failure of the socket to heal.

Use of pentoxifylline and tocopherol in the management of osteoradionecrosis

Osteoradionecrosis (ORN) is a complication of radiotherapy, and is difficult to manage once established. However, its pathogenesis has been reinvestigated, and it is now thought to be potentially amenable to treatment with pentoxifylline and tocopherol (vitamin E). We made a retrospective analysis of 62 patients with established ORN who were treated in this way. When only pentoxifylline and vitamin E was used ORN resolved in 14/25 (56%) but paradoxically, when it was combined with antibiotics, only 6/22 resolved (27%). The next stage would ideally be to incorporate the treatment in a randomised clinical trial against both standard antibiotic treatment and hyperbaric oxygen.

Prophylactic use of pentoxifylline and tocopherol in patients who require dental extractions after radiotherapy for cancer of the head and neck

Osteoradionecrosis (ORN) is a complication seen intermittently in patients who have had radiotherapy to the head and neck, and results of treatment with pentoxifylline and tocopherol (PVe) have been encouraging. As a consequence, some argue that this should be used prophylactically to lower the risk of ORN after dental extractions in this group. We retrospectively analysed data on 390 dental extractions in 82 patients who had had radiotherapy for cancer of the head and neck. Each had been given PVe prophylactically. Only one patient (1.2%) developed ORN (rate/tooth 0.26%). Patients had taken PVe for a mean (SD) of 11 (23) weeks preoperatively and 13.6 (18) weeks postoperatively. The incidence we found was lower than that normally associated with dental extractions in irradiated patients (7%).

Unerupted teeth associated with dentigerous cysts and treated with coronectomy: mini case series.

There is a resurgence of interest in coronectomy, but its appropriate application in the management of third molar teeth has yet to be defined. Dentigerous cysts associated with unerupted teeth are most commonly associated with mandibular third molars. In this case series we evaluate outcome after coronectomy of teeth with associated dentigerous cysts in cases where the inferior dental nerve was thought to be at risk, or there was an increased risk of mandibular fracture. We retrospectively studied 21 consecutive patients treated by coronectomy for dentigerous cysts at the Oral Surgery Department at Guys Hospital. The most commonly affected teeth were mandibular third molars (20/21). One patient had permanent injury to the inferior dental nerve, but no mandibular fracture or recurrence of cyst was reported. One patient required secondary retrieval of the retained root because of eruption. Coronectomy of unerupted teeth associated with dentigerous cysts is an effective treatment when there is high risk of injury to the inferior dental nerve injury or potential for mandibular fracture. Further work with larger numbers and longer follow-up is required to discover the long-term outcome of the electively retained root.

Axitinib-related osteonecrosis of the jaw

Tyrosine kinase inhibitors (TKIs) are oral chemotherapy drugs used primarily to treat leukemias, renal cell carcinomas, gastrointestinal stromal tumors, and neuroendocrine tumors. Within this group, a number of drugs have already been implicated in jaw necrosis. Axitinib (Inlyta) is a novel TKI currently licensed for the treatment of renal cell carcinoma. We report the first case, to our knowledge, of jaw necrosis solely related to this medication and review the literature surrounding TKIs and their implication in osteonecrosis of the jaw.

Multidisciplinary team approach in the oral rehabilitation of patients with cleidocranial dysplasia to achieve a functional aesthetic outcome

Cleidocranial dysplasia is a hereditary congenital disorder that results in delayed ossification of midline structures, and is caused by mutations in the RunX2 (runt-related transcription factor 2) gene located on the short arm of chromosome 6. Successful treatment depends on multidisciplinary assessment and a comprehensive staged treatment plan. We present a case series of 12 patients who were managed with a specifically tailored combination of surgery, orthodontics, and prosthodontics to provide a functional dentition and restore their smile and facial contour. Successful dental rehabilitation can be challenging in this group because patients often have multiple dental anomalies and a reduced quantity and density of alveolar bone. Rehabilitation with early intervention and a carefully planned multidisciplinary approach has been successful in the long term.