ENDO, 01/2010

The presence of internal or external tooth resorption often poses both diagnostic and treatment dilemmas for the clinician. When viewed radiographically, these defects can easily be mistaken for each other; and the status of the dental pulp and its role in the resorptive process can also be mistaken, especially if no diagnostic tests are conducted. Furthermore, the actual aetiology for these tooth maladies is elusive, but its determination is essential to develop the best treatment plan for the patient. Treatment plans may include a surgical repair, root canal procedure or even extraction, depending on the nature and extent of the defect. The purpose of this article is to characterise the nature and uniqueness of these two resorptive defects and to show how contemporary treatment modalities can be used in the retention of teeth that present with these challenges. Keywords: clastic-type cells, diagnosis, internal and external resorption, mineral trioxide aggregate, tooth retention

The use of Toxavit for pulpal devitalisation in a 30-year-old woman is presented. Improper use of this material resulted in necrosis of soft tissues and bone. The bone sequestrum was removed and examined under an electron microscope, revealing thick accumulation of plaque on the surface of the bone sequestrum and dissolution of bone material under the influence of microorgansims. Keywords: bone sequestrum, devitalisation, paraformaldehyde

This paper reviews the literature concerning computed tomography and other modalities such as spiral computed tomography, micro-computed tomography, cone-beam computed tomography, tuned-aperture computed tomography and optical coherence tomography in endodontics. Among the plethora of imaging modalities currently available, these recent imaging systems tend to draw attention from the clinicians. But still there is a lack of evidence-based data on the radiation dose and patient selection criteria for these imaging modalities, which calls for a set of guidelines to be introduced for their use in clinical practice in the future. Keywords: coherence tomography, computed tomography, cone-beam computed tomography, microcomputed tomography, optical tuned-aperture computed tomography, spiral computed tomography

Bacteria have been implicated in the pathogenesis and progression of pulpal and periapical diseases. The primary aim of endodontic treatment is to remove as many bacteria as possible from the root canal system and then create an environment in which remaining microorganisms cannot survive. Antibiotics form an important part of routine endodontic practice. They have been used routinely in children as an adjunct in a number of ways: systemically, locally and prophylactically. Systemic antibiotics have been used in clinical practice far more than is necessary. As topical agents they have been used as an intra-canal pulpotomy/pulpectomy medicament and root canal irrigant. Although their inadvertent use raises concern, the most important decision in antibiotic therapy should not be about which antibiotic should be used but whether antibiotics should be used at all. This paper reviews the role of antibiotics in paediatric endodontics by highlighting their effects and concerns in detail. Keywords: antibiotics, drugs, infected tooth, irreversible pulpitis, prophylactic, root canal treatment, systemic, topical

Aim: The objective of this study was to evaluate in vitro the accuracy of two electronic apex locators (Root ZX, J. Morita, Kyoto, Japan; and Apex Pointer™, Micro-Mega®, Besançon, France) for determining the root canal lengths of primary teeth with or without root resorption. Materials and Methods: Twenty primary human teeth, with or without root resorption, were used. After accessing the canals, 53 root canals were measured by the direct method and by two electronic apex locators (EALs). The actual length (AL) of each root canal was subtracted from the electronic measurement (EM) obtained by each device. The mean value of differences was obtained and percentages of acceptable measurements were determined. Statistical analysis was performed using ANOVA and the unpaired Student's t-test. Results: The mean values of differences between AL and EM for the Root ZX device were -0.07 mm (± 0.43) and 0.1 mm (± 0.63) in teeth without and with resorption, respectively. Corresponding values obtained by the Apex Pointer™ device were 0.01mm (± 0.47) and 0.09mm (± 0.63), respectively. The results showed that the majority of EMs were within ± 0.5 mm of the ALs. It was found that the accuracy of Root ZX was 75% and 76% for roots without and with resorption, respectively, while the Apex Pointer™ showed accuracies of 68% and 60%, respectively. No statistically significant difference was found between canal lengths obtained by both EALs and directly determined root canal lengths (P > 0.05). For the two devices, no significant differences were found between roots without and with resorption (P > 0.05). Conclusion: The two electronic apex locators (Root ZX and Apex Pointer™) showed accuracy in determining root canal length in primary teeth with and without root resorption. Keywords: electronic apex locator, endodontic treatment, primary teeth, root canal length

Mandibular molars display considerable variations with regard to the number of roots and root canals. One such anatomical variation is the presence of an additional root located distolingually, which is called radix entomolaris. An awareness and understanding of this unusual root and its canal morphology is important as it will contribute to the successful outcome of root canal therapy. This case report provides insight into the endodontic management of a mandibular molar with radix entomolaris, with the aid of spiral computer tomography. Keywords: distolingual root, mandibular molar, radix entomolaris, spiral CT

Aim: The purpose of this prospective study was to evaluate the prevalence of postoperative pain with respect to tooth vitality and preoperative pain in patients undergoing conventional root canal treatment. Methods: A total of 338 teeth from 317 patients, who were to receive conventional root canal treatment from four endodontists during a period of 18 months, were considered for this study. Based on the presence or absence of preoperative pain during the initiation of the treatment, the teeth were grouped as symptomatic (S) or asymptomatic (AS). Based on the presence or absence of haemorrhage during access cavity preparation, the teeth were grouped as vital (V) or non-vital (NV), respectively. The root canals were prepared using nickel-titanium ProTaper® rotary files and obturated using lateral compaction technique. The patients were recalled 1 week after the obturation for follow-up. At each visit, they were asked to record the postoperative pain as: none, slight, moderate or severe, since the previous visit. The data were statistically analysed using chi-square test. The level of significance was set at P 0.05. Results: 46 teeth were eliminated from the analysis of the results. Of the 292 remaining teeth, 66 fell into the non-vital asymptomatic (NV/AS) group, 60 in the non-vital symptomatic (NV/S) group, 39 in the vital asymptomatic (V/AS) group and 127 in the vital symptomatic (V/S) group. The prevalence of postoperative pain was significantly lower in the V/AS group compared to the NV/S (P = 0.002) and the V/S group (P = 0.029). The prevalence of preoperative pain was significantly higher in the NV group as compared to the V group (P = 0.049). The prevalence of postoperative pain was also significantly higher in the S group as compared to the AS group (P = 0.01). Conclusion: Pulp status and preoperative pain can be considered as factors that influence the occurrence of postoperative pain. Patients presenting with preoperative pain are at a higher risk of postoperative pain, particularly when the tooth is non-vital. Keywords: flare-up, postoperative pain, preoperative pain, root canal treatment, tooth vitality