Pathway to mercury-free dentistry: an insight into past, present, and future.

Purpose: The popularity of dental amalgam arises from its excellent long-term performance, ease of use, and low cost. However, there is a concern about the potential adverse health effects arising from exposure to mercury in amalgam. This review article critically discusses the safety of dental amalgam as a restorative material and our preparedness for a mercury-free road ahead. Materials and methods: A database search was performed on PubMed and Google scholar using the keywords: "mercury-free dentistry", "mercury toxicity", "amalgam substitutes", "amalgam mercury toxicity". Inclusion and exclusion criteria were specified clearly. Relevant literature was also searched in the dental textbooks. Results: Around 40 articles, highlighting mercury exposure among dental professionals and patients were included. Despite the overwhelming body of scientific evidence demonstrating amalgam to be a safe restorative material, concerns about the toxic effects of mercury persist. Conclusion: The real challenge is to find a suitable amalgam substitute and to follow the mercury hygiene measures closely.

Large Periapical or Cystic Lesions in Association with Roots Having Open Apices Managed Nonsurgically Using 1-step Apexification Based on Platelet-rich Fibrin Matrix and Biodentine Apical Barrier: A Case Series.

Teeth having open apices in the absence of a natural apical constriction pose several challenges during conventional endodontic treatment, especially when establishing an apical seal. Treatment is further challenging when these teeth are associated with large periapical or cystic lesions having resulted in expansion and/or thinning of adjacent cortical plates. Although surgical intervention is commonly adopted in the management of such cases, a conservative treatment option offering equally good prognosis is always desirable. This case series describes 3 cases: a 39-year-old woman, a 45-year-old woman, and a 15-year-old boy having teeth with concomitant open apices and large periapical/cystic lesions managed conservatively by (1) following a strict intracanal disinfection protocol, (2) intracanal aspiration with digital decompression of associated swelling, and (3) 1-step apexification for closure of the root apex by placing a preliminary barrier of platelet-rich fibrin (PRF) and a secondary barrier of Biodentine (Septodont, Saint-Maur-des-Fossés, France). In all 3 cases, the treatment outcomes, both clinical and radiographic, were highly satisfactory. PRF and Biodentine collectively rendered an apical plug that proved to be a suitable alternative to commonly used mineral trioxide aggregate in 1-step apexification. Biodentine provides good interfacial adhesion and sealing with dentin attributed to its property of hydroxyapatite crystal deposition at the material-dentin interface. Also, because of its bioactivity, it likely promotes the conversion of adjacent PRF into a calcific barrier, thus reinforcing the apical seal. Additionally, host-modulating responses of PRF contribute in expediting the healing process. Reasonable osseous healing in the periapex could be appreciated as early as 3 months in all patients. The rapidity with which healing occurred may have been an incidental finding but definitely draws attention.

Management of a Previously Treated, Calcified, and Dilacerated Maxillary Lateral Incisor: A Combined Nonsurgical/Surgical Approach Assisted by Cone-beam Computed Tomography.

Teeth with calcified canals, dilacerated roots, and associated large periradicular lesions involving both cortical plates pose a challenge to dentists. In addition to the nonsurgical endodontic treatment, such teeth may require surgical intervention with concomitant use of bone grafting materials and barrier techniques. These techniques, when combined with the use of a host modulating agent such as platelet-rich fibrin (PRF), may improve the chances of success. A 26-year-old woman was referred for dental treatment with a recurrence of an intraoral sinus tract 2 months after periradicular surgery in the upper anterior region. Clinical and radiographic examinations revealed a calcified and perforated maxillary left lateral incisor with a severely dilacerated root as well as an associated large radiolucent lesion surrounding the roots of the maxillary left central and lateral incisors. A cone-beam computed tomographic scan of the anterior maxilla showed erosion of the labial and palatal cortical plates in the same region. A calcified canal in the lateral incisor was negotiated up to the straight line portion of the canal. Periradicular surgery with root-end resection was performed, and root-end filling was performed with mineral trioxide aggregate. The perforation present on the middle third of the labial surface of the root was repaired with mineral trioxide aggregate, and the canal was cleaned, shaped, and obturated. A PRF scaffold was prepared and used with a collagen membrane and a freeze-dried bone allograft. Follow-up visits after 3 months, 6 months, and 1 year revealed satisfactory clinical and radiographic healing. The combined use of nonsurgical and surgical modes of treatment cannot be overemphasized in this case. The use of PRF along with a bone graft and a barrier membrane may have enhanced the speed of healing and the resolution of periradicular radiolucency by enhancing bone regeneration.

Endodontic management of nonvital permanent teeth having immature roots with one step apexification, using mineral trioxide aggregate apical plug and autogenous platelet-rich fibrin membrane as an internal matrix: Case series.

A tooth with blunderbuss canal and open apex can be an endodontic challenge because of difficulty in obtaining an apical seal, and existing thin radicular walls which are susceptible to fracture. To overcome the limitations of traditional long-term calcium hydroxide apexification procedures, nonsurgical one step apexification using an array of materials such as mineral trioxide aggregate (MTA) has been suggested. However, adequate compaction of MTA in teeth with wide open apices can be an arduous task, and an internal matrix is required for controlled placement of MTA against which obturating material can be condensed. Platelet-rich fibrin (PRF), a second generation platelet concentrate containing several growth factors that promotes hard and soft-tissue healing, has been used as an internal matrix to create an apical plug of MTA and hence prevent extrusion of filling materials. This case series presents the endodontic management of immature permanent teeth with open apices using internal matrix of autologous PRF membrane and one step apical barrier placement of MTA.

Management of a maxillary first molar having atypical anatomy of two roots diagnosed using cone beam computed tomography.

Most often, a clinician working on maxillary first molar when anticipates an aberration thinks of an extra canal but rarely does he preempt fewer canals. Maxillary first molar is a tooth, which has been extensively reviewed with respect to its external and internal morphology. Abundant literature related to its anatomy is available, but reports on incidence of two roots and two root canals in maxillary first molar are very limited. Here, a case of maxillary first molar is presented that had two roots: one palatal root with Type I canal configuration and one bulbous fused buccal root with Type V canal configuration; a unique root and canal configuration not seen in any of the earlier reported cases. Diagnosis of root canal aberrancy and subsequently, accurate management of the tooth was greatly facilitated by cone beam computed tomography (CBCT) scan. The relevance of CBCT in improving treatment prognosis is greatly emphasized in this report.

Pulp Revascularization- It's your Future Whether you Know it or Not?

Pulpal regeneration after tooth injury is not easy to accomplish. In teeth with immature apices and exposed vital pulp tissue, partial or complete pulpotomy is indicated to preserve pulpal function and allow continued root development. In many cases, injury causes loss of pulp vitality and arrested root development leading to a tooth with poor crown root ratio, a root with very thin walls, an open blunderbuss apex and development of apical pathosis. The ideal treatment in such cases would be to obtain further root development and thickening of dentinal walls by stimulating the regeneration of a functional pulp dentin complex. This outcome has been observed after reimplantation in avulsed immature permanent teeth but has been thought impossible in a necrotic infected tooth. This case series evaluates the efficacy of revascularization procedure in immature, non vital permanent teeth. Pulp regeneration was attempted in four patients at Department of Conservative Dentistry, ESIC Dental College, New Delhi using blood clotting approach. The cases were treated and followed up regularly at regular intervals ranging from 6 months to 3 years to assess the treatment response clinically and radiographically. The patients remained clinically asymptomatic with three out of four patients even responding positively to pulp responsiveness tests. Radiographic examination also revealed increased root formation and thickening of dentinal walls. It was concluded that the triad of a disinfected canal, a matrix (blood clot) in to which new tissue could grow and an effective coronal seal produced the desirable environment for successful revascularization.

Microorganisms in periradicular tissues: Do they exist? A perennial controversy.

There is no greater association between the basic science and the practice of endodontics than that of microbiology. One of the strongest factors contributing to the controversies often encountered in the endodontic field is the lack of understanding that the disease processes of the pulp and periradicular tissues generally have a microbiological etiology. The vast majority of diseases of dental pulp and periradicular tissues are associated with microorganisms. After the microbial invasion of these tissues, the host responds with both nonspecific inflammatory responses and with specific immunologic responses to encounter such infections. The aim of this study is to fill the gaps in our knowledge regarding the role of microorganisms in endodontics and to discuss in depth whether their presence in periradicular lesions is a myth or a reality. An electronic search was carried out on PubMed database (custom range of almost 50 years) and Google using specific keywords and phrases. Inclusion and exclusion criteria were specified and around 50 articles were found suitable for inclusion. Full text of all the articles was retrieved and studied. Appropriate data were extracted and pooled and finally synthesized. It is important to understand the close relationship between the presence of microorganisms and endodontic disease process to develop an effective rationale for treatment.

CBCT diagnosis and endodontic management of a maxillary first molar with unusual anatomy of two palatal canals: A case report.

It is crucial for any clinician to have a thorough knowledge about the normal anatomy of tooth and always be vigilant for any variations to ensure endodontic success. An anatomic variant like additional canals in the palatal root of maxillary molar is not commonly reported. This clinical case report presents the application of cone beam computed tomography as a useful imaging technique in endodontics for the management of teeth with aberrant anatomy. Here, maxillary first molar having two canals in the palatal root, two canals in mesiobuccal root and one canal in distobuccal root was managed successfully using cone beam computed tomography scan as a diagnostic aid.

Endodontic and esthetic management of a dilacerated maxillary central incisor having two root canals using cone beam computed tomography as a diagnostic aid.

Traumatic injuries to the primary dentition are quite common. When primary teeth are subjected to trauma, force transmission and/or invasion of the underlying tooth germs lying in close proximity can result in a variety of disturbances in the permanent successors. Few of these disturbances include hypoplasia, dilaceration, or alteration in the eruption sequence and pattern. Dilaceration is defined as an angulation or sharp bend or curve in the linear relationship of the crown of a tooth to its root. A rare case of maxillary left central incisor having crown dilaceration and Vertucci's type II canal configuration with symptomatic periapical periodontitis is reported. Cone beam computed tomography was used for better understanding of the anomaly and complicated root canal morphology. The tooth was successfully managed by nonsurgical root canal therapy and restoration with resin composite to restore esthetics.

Biomaterials in tooth tissue engineering: a review.

Biomaterials play a crucial role in the field of tissue engineering. They are utilized for fabricating frameworks known as scaffolds, matrices or constructs which are interconnected porous structures that establish a cellular microenvironment required for optimal tissue regeneration. Several natural and synthetic biomaterials have been utilized for fabrication of tissue engineering scaffolds. Amongst different biomaterials, polymers are the most extensively experimented and employed materials. They can be tailored to provide good interconnected porosity, large surface area, adequate mechanical strengths, varying surface characterization and different geometries required for tissue regeneration. A single type of material may however not meet all the requirements. Selection of two or more biomaterials, optimization of their physical, chemical and mechanical properties and advanced fabrication techniques are required to obtain scaffold designs intended for their final application. Current focus is aimed at designing biomaterials such that they will replicate the local extra cellular environment of the native organ and enable cell-cell and cell-scaffold interactions at micro level required for functional tissue regeneration. This article provides an insight into the different biomaterials available and the emerging use of nano engineering principles for the construction of bioactive scaffolds in tooth regeneration.

In vitro evaluation of the accuracy of two electronic apex locators.

This study involves evaluating the accuracy of two electronic apex locators (EALs), Raypex and Neosono Co-pilot. Ten single-root human anterior teeth were used for the study. The crown was sectioned to gain access to the root canal. For each tooth, the reference (or control) length, corresponding to the actual length, was determined, after which all the teeth were measured independently. The results obtained with each EAL were in turn compared with the corresponding control length. The statistical analysis of the results showed that EAL reliability in detecting the apex varies from 80 to 85% for Neosono systems and 85 to 90% for the Raypex systems. Combined with a high observer concordance, these results suggest that electronic root canal measurement can be an objective and acceptably reproducible technique.