ENDO, 02/2020

Aim: To systematically review current evidence comparing the use of mineral trioxide aggregate and calcium hydroxide for direct pulp capping in permanent teeth with mature root development. Materials and methods: A search of multiple databases was undertaken for randomised controlled trials comparing use of mineral trioxide aggregate and calcium hydroxide for direct pulp capping. Other sources, including trial registries and reference lists, were also searched. Three reviewers independently conducted the screening, data extraction and critical appraisal. Following screening, four studies were identified and analysed. Results: Three of the four studies were identified as being at high risk of bias. Two studies reported statistically significant superiority of mineral trioxide aggregate over calcium hydroxide, although one of these studies had the highest risk of bias. Two studies demonstrated the superiority of mineral trioxide aggregate over calcium hydroxide for direct pulp capping, which was not statistically significant. Conclusions: There is evidence from the randomised controlled trials that mineral trioxide aggregate performs better than calcium hydroxide for direct pulp capping of permanent teeth with complete root development following pulp exposure during caries removal, but not in cases of iatrogenic or traumatic exposures. This supports the European Society of Endodontology 2019 position statement on the management of deep caries and the exposed pulp. There are indications that the superiority of mineral trioxide aggregate over calcium hydroxide for direct pulp capping becomes more pronounced over time; the need for longer-term studies is questionable given the weight of evidence already available from short- to medium-term randomised controlled trials. Keywords: calcium hydroxide, dental pulp exposure, direct pulp capping, mineral trioxide aggregate, systematic review

Nanotechnology is defined as science and engineering performed on a nanoscale, which is 1 to 100 nanometres (nm). These particulates exhibit a notably large surface area that is ideal for biocompatibility, drug delivery and material strength. Nanoparticles' applications in dentistry are in their infant stages and consist of treating dentinal hypersensitivity, decreasing the prevalence of dental plaque and improving the currently used dental materials, with increased antibacterial efficacy. Of immediate and pertinent interest to the endodontist is the need for a more effective intracanal irrigant, vis à vis disinfection; thus warranting a nanoscopic approach via liposomes in a targeted delivery of antimicrobial agents. The overall role of nanoparticles in endodontics may not be overarchingly obvious, but its recent impact on tissue engineering is remarkable with future integrations and applications in the offing. This brief review attempts to illustrate some of the prospective endodontic applications of nanotechnology, prevalent in the biomedical community, in addition to the relevant obstacles facing its clinical use today. Keywords: antimicrobials, composite materials, disinfection, hypersensitivity, irrigation, nanoparticles, regeneration, root canal sealants

Aim: One of the main objectives of root canal treatment is disinfection of the root canal system. However, this goal is hampered by complex root canal anatomy. Practitioners should be familiar with the morphology of the roots of all the teeth and the associated intricate root canal anatomy for effective debridement, disinfection and obturation to be achieved. This article presents the successful management of two maxillary first molars with two canals in a single and separate distobuccal root and reviews the available literature on root canal configurations of single and separate distobuccal roots of maxillary molars. Materials and methods: Nonsurgical root canal treatment of two maxillary first molars was performed with the aid of a dental operating microscope and cone beam computed tomography. The literature review was conducted using the PubMed database (http://www.ncbi.nlm.nih.gov/pubmed). Results: The overall incidence of two-canalled distobuccal roots in maxillary molars ranged from 1.0% to 2.3%. The most common root canal configurations found in clinical/laboratory studies were Vertucci type IV (2-2) and type II (2-1). In clinical case reports, Vertucci type II (2-1) was the most common configuration. The incidence of three-canalled distobuccal roots was found to be 0.72% only. Clinicians should always keep in mind the high complexity of the root canal system. All possible efforts should be made to locate and treat root canal variations to enhance the prognosis of endodontic treatment. Keywords: disinfection, distobuccal root, maxillary first molar, root canal variations

Aim: To investigate whether Reciproc and Reciproc blue instruments (both VDW, Munich, Germany) are effective in re-treating a calcium-silicate–based sealer compared with re-treating an epoxy resin–based sealer. The time to reach patency (tp) and time to complete the re-treatment (tcr) were investigated as well as the amount of remaining filling material. Materials and methods: The root canals of 60 single-rooted teeth were obturated with either TopSeal (Dentsply Sirona, Ballaigues, Switzerland) or EndoSequence BC Sealer (Brasseler, Savannah, GA, USA). The teeth were randomly subdivided into four groups of 15 teeth for re-treatment with either a Reciproc R25 or a Reciproc blue R25: the epoxy Reciproc group (ER), the epoxy blue group (EB), the calcium-silicate Reciproc group (CSR) and the calcium-silicate blue group (CSB). During re-treatment the times were recorded and after re-treatment the remaining material was evaluated with radiographs. The experimentally obtained data were subjected to a two-way ANOVA. Results: Regarding the sealers, there were significant differences for tp (seconds) (mean calcium-silicate = 201.0; mean epoxy = 90.8; P 0.0001) and for tcr (seconds) (mean calcium-silicate = 326.4; mean epoxy = 229.7; P = 0.0003). Between the instruments there were no significant differences for tp (seconds) (mean Reciproc = 134.4; mean blue = 157.3; P = 0.1545) or for tcr (seconds) (mean Reciproc = 278.1; mean blue = 278.0; P = 0.9983). For the remaining material (%), there were no significant differences found (mean calcium-silicate = 2.06; mean epoxy = 1.69; P = 0.1623; and mean Reciproc = 1.84; mean blue = 1.91; P = 0.7965). Conclusions: It took longer to re-treat calcium-silicate sealers, but there were no significant differences in the amounts of remaining filling material. Both files were equally effective in re-treating root canals. Keywords: calcium-silicate, endodontic sealer, epoxy resin, Reciproc, Reciproc blue, re-treatment

Aim: The aim of this study was to compare the shaping ability of four multi-file systems and one single-file system in simulated S-shaped canals. Materials and methods: Fifty S-shaped canals in resin blocks (Endo Training Bloc S-shape, Dentsply Sirona, Salzburg, Austria) were prepared to an apical size of 25.06 using ProTaper Next (Dentsply Sirona, Ballaigues, Switzerland), HyFlex CM (Coltène/Whaledent, Langenau, Germany), F6 SkyTaper (Komet, Lemgo, Germany), BioRace (FKG Dentaire, La-Chaux-des-Fonds, Switzerland) and Mtwo (VDW, Munich, Germany) systems (n = 10 canals/group). Canal transportation was assessed by comparing the pre-instrumentation and post-instrumentation images under a stereomicroscope. Material removal was measured using a digital template and image analysis software. Deformation of instruments and preparation time were also recorded. The data were statistically analysed by considering the clinical relevance and the ability to maintain the S-shaped form. Results: Canals prepared with HyFlex CM, ProTaper Next and F6 SkyTaper remained better centred compared with those enlarged with the BioRace and Mtwo systems, which removed statistically significantly greater amounts of resin from the inner side of both curvatures (P 0.05). F6 SkyTaper and BioRace were the two fastest systems (P 0.001). No instrument fractures occurred during canal preparation. About 78% of all HyFlex CM files were suitable for reuse. Conclusion: Under the conditions of this study, all five nickel-titanium systems were safe to use. The heat-treated systems HyFlex CM and ProTaper Next maintained the original canal curvature better than instruments made of conventional nickel-titanium. Less tapered instruments at the sequence's beginning had a positive effect on the systems' centring ability. Keywords: CM-wire, M-wire, S-shaped, shaping ability, simulated

Avulsion of permanent teeth is one of the most serious complications, presenting in 0.5 to 3% of all traumatic dental injuries. The prognosis depends on the timeliness of the management following trauma, on the specialised attention received after the avulsion and on the extraoral time of the avulsed tooth. Failure to provide appropriate management may lead to inflammatory or replacement/ankylosis external root resorption (ERR). When the latter type of EER occurs, decoronation and root submergence are often proposed as treatment plan. This case report addresses the management of an avulsed tooth that was treatment-planned for a decoronation procedure. Keywords: avulsion, decoronation, root resorption

Aim: An odontogenic, extraoral/cutaneous fistula located in the facial or neck area is a rare symptom of a long-term, chronic infection caused by a complication of caries, dental trauma or periodontal inflammation. This article presents a case of a patient with a cutaneous fistula on the chin that healed after root canal treatment. Materials and methods: To apply an appropriate treatment that would ensure therapeutic success, a thorough examination of the patient was conducted and the correct diagnosis was made. An extraoral and intraoral examination was performed, including inspection of the soft and hard tissues, beginning with visual analysis and palpation, followed by status of pulp and periapical tissues testing, and finishing with radiological examinations. A panoramic and a periapical radiograph were taken of the mandibular incisors. In the clinical case discussed in this report, despite the prior long-term, improper medical management, a satisfactory treatment effect was finally achieved by performing an antiseptic root canal treatment of the mandibular left incisors. Results: The elimination of inflammation of the causal teeth through endodontic treatments performed led to healing of the skin lesion without surgical excision or systemic antibiotic therapy. Conclusion: In the differential diagnosis of cutaneous fistulae occurring in the facial or neck area, an odontogenic aetiology should always be taken into consideration. Keywords: aetiology, calcium hydroxide, cutaneous fistula, endodontic treatment, extraoral fistula, periapical inflammation

This report describes root canal treatment through cone beam computed tomography and magnification through a surgical microscope of C-shaped mandibular second premolars in the same patient. The mandibular left second premolar with Sert and Bayirli type XV classification was treated for symptomatic irreversible pulpitis and apical periodontitis. The mandibular right second premolar with Vertucci type V classification was re-treated because of a deficient previous root canal treatment, which also involved buccal canal transportation, furcal perforation and two separated instruments in the lingual canal besides symptomatic apical periodontitis. During the root canal re-treatment, buccal canal transportation and furcal perforation were sealed with mineral trioxide aggregate (MTA-Angelus, Londrina, PR, Brazil), separated instruments were removed and a better obturation was achieved. In the 6-month follow-up the patient reported no symptoms, the radiographs of both teeth showed no apical radiolucencies and the percussion tests were negative. For this case, cone beam computed tomography and magnification were essential to identify this unusual root canal morphology, allowing successful endodontic treatment to be achieved. Keywords: C-shaped mandibular premolars, cone beam computed tomography, Sert and Bayirli type XV root canal configuration