A survey of dental residents' expectations for regenerative endodontics.

INTRODUCTION: The objective was to survey a group of dental residents regarding their expectations for using regenerative endodontic procedures as part of future dental treatments. METHODS: After institutional review board approval, the opinions of 32 dentists who were having postgraduate residency training to become specialists in a dental school were surveyed. The survey had 40 questions about professional status, ethical beliefs, judgment, and clinical practice. RESULTS: It was found that 83.9% of dentists had no continuing education or training in stem cells or regenerative endodontic procedures. Results showed that 96.8% of dentists are willing to receive training to be able to provide regenerative endodontic procedures for their patients. Of the total group, 49.1% of dentists already use membranes, scaffolds, or bioactive materials to provide dental treatment. It was determined that 47.3% of dentists agree that the costs of regenerative procedures should be comparable with current treatments. It was also found that 55.1% of dentists were unsure whether regenerative procedures would be successful. CONCLUSIONS: Dentists are supportive of using regenerative endodontic procedures in their dental practice, and they are willing to undergo extra training and to buy new technology to provide new procedures. Nevertheless, dentists also need more evidence for the effectiveness and safety of regenerative treatments before they will be recommended for most patients.

Keratocystic odontogenic tumour: reclassification of the odontogenic keratocyst from cyst to tumour.

The purpose of this paper is to review the features and behaviour of the odontogenic keratocyst (OKC), now officially known as the keratocystic odontogenic tumour (KCOT); to analyze a series of histologically confirmed KCOT cases; and to review and discuss the redesignation of KCOT and the implications for treatment. Redesignation of the OKC as the KCOT by the World Health Organization (WHO) is based on the well-known aggressive behaviour of this lesion, its histology and new information regarding its genetics. Abnormal function of PTCH, a tumour suppressor gene, is noted to be involved in both nevoid basal cell carcinoma syndrome and sporadic KCOTs. Normally, PTCH forms a receptor complex with the oncogene SMO for the SHH ligand. PTCH binding to SMO inhibits growth-signal transduction. SHH binding to PTCH releases inhibition of the signal transduction pathway. If normal functioning of PTCH is lost, the proliferation-stimulating effects of SMO are permitted to predominate. A review of the literature was conducted and results were tabulated to determine whether treatment modality is related to recurrence rate. More aggressive treatment - resection or enucleation supplemented with Carnoy"s solution with or without peripheral ostectomy - results in a lower recurrence rate than enucleation alone or marsupialization. Notably, the recurrence rate after marsupialization followed by enucleation is not significantly higher than that following the so-called aggressive modalities. Our case series consists of 21 patients treated for KCOTs. Results were organized to demonstrate recurrence as it relates to size of lesion and time since treatment and incidence as it relates to patient age and location in the jaws. In our series, the average KCOT surface area measured radiographically was 14 cm2. Most lesions were within the 0-15 cm2 range and lesions in this range resulted in the greatest number and proportion of recurrences. The recurrence rate of 29% in our case series was consistent with previously established data; all recurrences occurred within 2 years post-intervention. The incidence of primary lesions was highest in the age group 70-79 years; most lesions occurred in the posterior mandible. WHO"s reclassification of the OKC as the KCOT based on behaviour, histology and genetics underscores the aggressive nature of the lesion and should motivate clinicians to manage the disease in a correspondingly aggressive manner. The most effective interventions for the KCOT are either enucleation with Carnoy"s solution, or marsupialization with later cystectomy. Future treatment may involve molecular-based modalities, which may reduce or eliminate the need for aggressive surgical management.