ENDO, 02/2016

Pulp stones are calcified bodies in the dental pulp of the teeth in the primary and permanent dentition. They are found in healthy, diseased and even unerupted or impacted teeth. This case report presents the diagnostic management of a 22-year old female patient with general pulp calcification that coexists with molar incisor hypomineralisation and compound odontoma. The diagnostic procedure revealed several conditions that could be implicated: possible metabolic imbalance, bruxism, orthodontic treatment and genetic predisposition. Blood tests and urine analysis results excluded the possibility of metabolic imbalance. Clinical examination excluded bruxism and orthodontic treatment as implicated factors. The patient's family dental history revealed that the patient's mother also presents general pulp calcification. The aim of this article is to describe the diagnostic management of the patient and to highlight that general pulp calcification is not such a common finding; clinicians should be suspicious and investigate the possible metabolic imbalance, dysfunction or other correlated systematic diseases which may contribute to their early diagnosis. Keywords: dental pulp, general pulp calcification, pulp stone

Objective: This in vitro study assessed the radiopacity changes of Biodentine as a root-end filling material, using soft and hard tissue simulation by direct digital radiographic techniques. Materials and methods: Sixty disk specimens of Biodentine (6 mm diameter and 1 mm thickness) were prepared. The specimens were stored at 37°C for 48 h. Then they were divided into three groups (n = 20); Group I: specimens radiographed with aluminium step-wedge; Group II: bone segment was prepared to insert and standardise the specimen placement and then positioned between the digital sensor and X-ray machine; Group III: utility wax (30 mm thickness) was placed at the buccal aspect of bone, covering the whole test region. For all groups, three radiographs were taken for each specimen using intraoral sensor Carestream CS, operating at 60 kV, 7 mA and 0.24 s. The object-to-focus distance was 30 cm. The mean grey value (MGV) was measured using the densitometry analysis tool of the Image Tool of CS2100 software. The radiopacity value was determined according to the radiographic density, which was also converted into millimetres of thickness of aluminium equivalent (mm Al). Data (mm Al) were submitted to the one-way ANOVA and Tukey's test. Results: The specimens evaluated under conditions with simulated hard and soft tissue showed values above the minimum recommended by the ISO 6867: 2012 specification, while the materials alone displayed the lowest values (group I). Conclusion: Biodentine is suitable as a root-end filling material in terms of radiographic features. Keywords: Biodentine, radiopacity, root-end filling materials

Aim: The aim of this study was to compare the cleaning ability of a single file system (OneShape) versus multi-file systems (ProTaper Universal & ProTaper Next) in curved root canals. Materials and methods: Sixty mesiobuccal roots from extracted mandibular molars were divided into three groups (n = 20): PTU, prepared by ProTaper Universal system; PTN, prepared by ProTaper Next system; and OS, prepared by OneShape system. Teeth were longitudinally split into two halves for evaluation by stereomicroscope. Digitised images were analysed using ImageJ Software for the amount of debris along the canal walls. Results: No significant difference was found between the three groups in the coronal third of the canals (P = 0.17). However, the OneShape group recorded a significantly higher percentage of debris in the middle and apical thirds (P = 0.003 and P = 0.023, respectively) Conclusions: The single-file system showed relatively decreased cleaning ability in curved canals when compared to the use of rotary full-sequence NiTi systems. Keywords: cleaning ability, OneShape, ProTaper Next, single file

Aim: The purpose of this study was to evaluate the effect of the angle and radius of root canal curvature on the resistance to cyclic fatigue of ProTaper Next (Dentsply Maillefer, Ballaigues, Switzerland) and NRT (Mani, Toshigi-Ken, Japan) rotary nickel-titanium instruments. Methods: One hundred and sixty files were rotated until fracture in simulated canals of 60° and 45° angles of curvature with two different radii (5.0 and 2.5 mm), using a custom-made testing platform. The number of cycles to failure (NCF) was calculated and statistical analysis was carried out using three-way analysis of variance (ANOVA) (P ≤ 0.05) and Bonferroni's post-hoc test. Scanning electron microscope analysis was done to assess fractured files. Results: The NRT system showed a higher mean NCF when compared to ProTaper Next, when the angle of curvature was 60° or 45° in both 5.0 mm and 2.5 mm radii. Statistically significant differences were found between the NCF mean values of NRT and ProTaper Next, when the radius was 5.0 mm, however no significant differences were found when the radius was 2.5 mm. Conclusions: It was concluded that when the angle of root canal curvature increased and the radius decreased, the cyclic fatigue resistance of NRT and ProTaper Next files decreased. Keywords: Cyclic fatique, NRT, ProTaper Next

Aim: The aims of the present survey were to record the views of patients on their experience of rubber dam (RD) use in an objective manner and evaluate the influence of several personal and clinical factors on patient opinion. Methodology: A simple questionnaire was distributed to 116 patients receiving root canal treatment in the Dental School of Athens University. The sample was divided into two groups; adult patients receiving treatment under RD from (a) final-year students and (b) postgraduate students. Data were analysed using: a) exact tests and b) univariate and multivariate ordinal logistic models. Results: Overall, patients' current experience and preference for future RD use were positive. Although slight differences were detected between the two groups of patients, concerning their experience and future preference, no clear trend was found. A positive association between current experience and future RD use was demonstrated among all participants (P < 0.001). The probability of a less favorable outcome regarding patients' current experience and their preference for future RD use were higher as the placement time was increasing (P < 0.001 and P = 0.009, respectively). The probability of a less favorable outcome regarding patients' current experience was higher as usage duration was increasing and the effect was more pronounced amongst patients treated by postgraduate students. Conclusions: Evidence suggesting positive patient attitudes to RD use is presented. Overall, patient opinion concerning current experience of RD use and future preference did not differ significantly in relation to the experience of the clinicians. Patients' current experience exerted significant leverage on their future preference. Keywords: future preference, patients' current experience, rubber dam

The first mandibular molar shows a complex range of anatomical variations concerning the number of roots and root canals. The mesial root usually has two canals, whereas the distal root mostly has one canal. Only 5 cases presenting four canals in the mesial root of a mandibular molar were reported. However, the occurrence of a distal root with three canals in a mandibular molar with six canals was rarely described in scientific literature. The main objective of these case reports is to draw attention to the clinical challenges of possible complex anatomic configurations in canals of mandibular first molars. Keywords: complex root canal pattern, dental operating microscope, mandibular first molar, root canal morphology