OBJECTIVES: The aim of this study was to gain understanding into the perceptions of undergraduate dental students regarding their levels of competence and confidence when preparing endodontic access cavities MATERIALS AND METHOD: Anonymous survey forms were given to 100 undergraduate dental students at Sefako Makgatho Health Sciences University, School of Oral Health Sciences. Students were asked to indicate their self-confidence level by using a 5-point Likert scale as 'not confident', 'manageable', 'comfortable and confident',' extremely confident' and 'never done it'. RESULTS: The response rate was 75 % out of 100 students. The majority of the participants (88%) indicated that they would perform endodontic access cavity preparation with ease on anterior teeth and the lowest (43%) confidence levels was indicated on multi-rooted posterior teeth Keywords: Perceptions, clinical experiences, endodontic access cavity preparation, teaching and learning.

Calcific metamorphosis (CM) or pulp canal obliteration (Fig. 1A-C) is a common occurrence following concussion and subluxation injuries. 1,2 Although the exact mechanism by which the canal obliterates is unknown, it is believed to be related to neurovascular damage and deposition of hard tissue within the canal. 3,4 This calcification of the pulp canal space results in a loss of translucency leaving the crown with a yellow discolouration (Fig. 2 and 3). 5 CM can be clinically detected as early as three months after injury but remains undetected in most cases for up to a year after trauma. [6][7][8] Asymptomatic teeth presenting with CM do not initially require treatment other than annual review. 1,9 However, the pulp status within partially obliterated canals may eventually lead to apical pathology requiring treatment. [10][11][12][13][14] Treatment protocols and exact intervention times for the treatment of CM remains controversial and a challenge for even the skilled clinician. [15][16][17] CM is a common outcome of trauma frequently associated with anterior teeth of young adults and is characterised by partial or total obliteration of the root canal. 6,8,15

Endodontic treatment may sometimes fail because the morphological features of the tooth can adversely affect the treatment procedures. Mandibular canines can present with complex internal anatomy and many investigators have reported associated anatomical variations. This paper describes three clinical case reports of mandibular canines, each with two roots and two canals. In addition, the prevalence, aetiology, root morphology and the clinical and radiographic diagnoses for mandibular canines that present with this anatomical variation will be discussed. Root canal treatment on a tooth is performed with the intention of eliminating any infection and preventing the possibility of re-infection in the root canal system. 1 The configuration of the root canals of any tooth can be complex and when treatment fails to locate, clean, shape and obturate them effectively, complications can arise. These include post-operative pain and disease in the affected tooth and surrounding structures. 1-3 Numerous factors can contribute to the failure of endodontic treatment and may include persistent infection in the root canal (which was not eliminated at the initial treatment phase), inadequate approach to cleaning and shaping (leading to poor root canal preparation), broken instruments and incomplete obturation of the prepared root canal. 4 A further variation includes the mandibular canine with two roots and two root canals, having an incidence of up to 12.08%. 8,15-17 Another rare configuration was reported by Heling and co-workers, who treated a mandibular canine with two roots and three canals. 14

Apexification is defined as a method to induce a calcified barrier at the root tip of a tooth with an open apex or to encourage the continued apical development of an incomplete root in teeth with necrotic pulps. Two case reports are presented in which teeth with large open apices and immature roots were clinically managed by placing demineralised freeze-dried bone allograft (DFDBA) as a matrix before placement of Mineral Trioxide Aggregate (MTA) as an apical barrier. The indications for and advantages of using DFDBA and MTA are discussed.

Once root canal treatment is considered, the treating clinicians must be aware of the real possibility that complications and unforeseen accidents can occur during any stage of the treatment. Complications and accidents may include instrument separation, root perforation on different levels and ledge formation.