Dens invaginatus is a developmental malformation, in which there is an infolding of enamel into dentine. These infolds represent stagnation sites for bacteria and can predispose to dental caries. The carious infection can spread via enamel and dentine to contaminate the pulp and cause soft tissue necrosis. The altered and sometimes complex anatomy of affected teeth can make endodontic management challenging. Early diagnosis is therefore essential as prophylactic treatment of the dens can prevent degeneration and pulpal necrosis. The aim of this article is to review the aetiology, classification, diagnosis and management of teeth affected with dens invaginatus. Emphasis will be placed on describing the clinical features of this anomaly. Treatment options, management strategies and the challenges faced in managing this condition will be discussed.

The first part of this series on the conventional rehabilitation of oncology patients with hard palate defects discussed the dental challenges posed by oncology patients and the surgical/restorative planning interface for conventional dental rehabilitation. This article will describe Aramany's classification of hard palate defects, Brown's classification of palatal defects and focus on the basic principles of obturator design which need to be appreciated when prosthetically rehabilitating a patient with a hard palate defect. Clinical relevance statementA good understanding of basic removable prosthodontic theory relating to denture design, dental materials science and head and neck anatomy is an absolute prerequisite when designing an obturator for a patient. Learning ObjectiveThis article will describe: (a) how hard palate defects can be classified and (b) the basic principles of obturator design which need to be appreciated when rehabilitating a patient with a maxillectomy defect.

This article is the first in a series of three papers that will discuss the conventional non-implant retained prosthodontic rehabilitation of oncology patients with surgically acquired hard palate defects. In this first paper, the dental challenges posed by the oncology patients will briefly be discussed. The interface between the specialist restorative dentist and the maxillofacial surgeon when planning the conventional dental rehabilitation of an oncology patient with a hard palate defect will be discussed in detail. Clinical Relevance: To highlight the importance of the restorative dentistry/surgical interface when planning a treatment for a patient requiring a maxillectomy and conventional obturation.

Patients with a hyper-responsive gag reflex pose dentists with a challenging problem. The gag reflex of some patients may be so severe that patients (and operating clinician) may favour extraction of any painful, infected teeth as opposed to more lengthy and complicated procedures such as root canal therapy. However, consistently adopting this approach may render the gagging patient completely edentulous. Such patients may then present to the dental surgeon requesting tooth replacement with some form of denture. This in itself can be a challenging task given the difficulties one may experience whilst taking impressions in this cohort of patients. This article will discuss the prosthetic management of the maxillary arch in edentulous patients with a severe gag reflex. There will be particular emphasis on the aetiology and physiology of the gag reflex, impression-taking techniques to allow the construction of an acrylic training plate (as an interim measure), principles of training plate design and construction of the definitive removable denture. Clinical Relevance: Removable training plates can be used as an interim measure to desensitize edentulous gagging patients before providing them with a definitive removable denture.