Ability of new obturation materials to improve the seal of the root canal system: A review

Abstract

Objectives New obturation biomaterials have been introduced over the past decade to improve the seal of the root canal system. However, it is not clear whether they have really produced a three-dimensional impervious seal that is important for reducing diseases associated with root canal treatment. Methods A review of the literature was performed to identify models that have been employed for evaluating the seal of the root canal system. Results and Significance In-vitro and in-vivo models are not totally adept at quantifying the seal of root canals obturated with classic materials. Thus, one has to resort to clinical outcomes to examine whether there are real benefits associated with the use of recently-introduced materials for obturating root canals. However, there is no facile answer because endodontic treatment outcomes are influenced by a host of other predictors that are more likely to take precedence over the influence of obturation materials. From the perspective of clinical performance, classic root filling materials have stood the test of time. Because many of the recently-introduced materials are so new, there is not enough evidence yet to support their ability to improve clinical performance. This emphasizes the need to translate anecdotal information into clinically relevant research data on new biomaterials.

Assessment of Push-Out Bond Strength and Interfacial Adaptation of Two New Endodontic Sealers; Endosequence Bc and Mta Fillapex to Root Canal Dentine (An in Vitro Study).

“…Bonding of the sealer to dentine either by mechanical retention or chemical adhesion or both is important mainly to maintain a tight seal between them after treatment against bacterial leakage. Additionally, it is important to withstand stresses produced during function or due to successive treatment as post preparation or coronal restoration (8,9,10,11 In the present study, adaptation of the sealers to dentine wall have been tested in addition to the bond strength, as strong bond of the sealer to dentine wall does not assure that it covers and adapts to the entire surface of canal wall. It was proposed that, presence of interfacial gap areas due problems in the bond, manipulation or shrinkage of the sealer could allow leakage of bacteria and their byproducts (12,13).…”

Degree of conversion of a self-adhesive endodontic sealer when used as bulk material

“…For micro-Raman spectroscopy, we used a focal size of 1 µm, which is sensitive to inhomogeneity. Extended setting shrinkage behavior jeopardizes the seal of root canals filled with these more rapidly polymerizing resin sealer systems (22), particularly when manufacturers recommend the use of light-curing through canal orifices to create an immediate coronal seal (18). The presence of intracanal voids was revealed by micro-CT (23).…”

“…Although the present experimental conditions exist only at the canal ends or as a result of anatomic accidents in actual clinical situations (6), they allowed us to isolate the variable under study. Different aspects of RSSE, including its sealing capacity (16) and its bond strength to root dentin (17), have been studied by avoiding the effects of Resilon, the recommended core material (18). Although previous studies reported low adhesion values between Resilon and a methacrylate resin sealer (19), the effects of Resilon disposable methacrylate free radicals, if any, on the DC of RSSE are unknown.…”

Volume of sealer in the apical region of teeth filled by different techniques: a micro-CT analysis

“…1 The efficiency of a filling material in properly sealing the root canal is determined by its physical properties and handling characteristics. 2,3 No other filling material has been as successful and widely accepted as gutta-percha, probably owing to its favorable properties such as biocompatibility, plasticity, radiopacity, and easy insertion and removal from the root canal. 4,5,6,7,8 Despite these beneficial features, gutta-percha shows no adhesion to dentine, resulting in gaps between the cone and root canal walls.…”

“…3,10,11 Among the filling techniques pertaining to the root canal system, the lateral condensation (passive or active) technique is widely used 7,6,12 and offers the advantage of a controlled placement of gutta-percha into the root canal. 2,7 The passive lateral condensation technique does not require the application of external pressure using finger spreaders and may allow premature coronal filling because the coronal portion of the accessory cone has a larger diameter 10 .…”