Calcium Hydroxide Liners: A Literature Review PDF

Clinical, Cosmetic and Investigational Dentistry Dovepress...

Clinical, Cosmetic and Investigational Dentistry Dovepress open access to scientific and medical research Open Access Full Text Article REVIEW Calcium hydroxide liners: a literature review This article was published in the following Dove Press journal: Clinical, Cosmetic and Investigational Dentistry 13 July 2017 Number of times this article has been viewed Naji Ziad Arandi Objective: This review integrates the literature on cavity liners and current concepts of pulp Faculty of Dentistry, The Arab protection with the aim of establishing a better understanding of the role of calcium hydroxide American University, Jenin, Palestine as a cavity liner. Materials and methods: A search was conducted through PubMed, MEDLINE, and Ovid for articles with the criteria for the following terms: cavity liners and bases, pulp protection, and calcium hydroxide liners. No specific inclusion or exclusion criteria were applied as to what articles would be included in this review. It was hoped that the extent of the literature reviewed would be as comprehensive as possible. Conclusion: This review underlines the fact that calcium hydroxide liners should only be used in the deepest spots in the cavity where the remaining dentine thickness is ≤0.5 mm. A protective layer of resin-modified glass ionomer should always follow the application of calcium hydroxide liners. Keywords: liners, calcium hydroxide, pulp protection, pulp therapy, bases Introduction One of the aims of operative dentistry is to preserve the pulp vitality in compromised teeth: one method used for this reason is the use of liners and bases. This involves the placement of protective materials on the unexposed pulp to maintain its health and to stimulate defensive repair by tertiary dentine deposition. The use of liners and bases under restorations has been common practice for many years and continues to be pro- moted in operative dentistry textbooks as an essential part of restorative procedures.1–3 The concepts related to pulp protection have been constantly revisited as the knowledge and understanding of the tooth and dental materials evolve.4–8 Traditionally, liners have been used to protect the pulp from the potential toxic effects of restorative materials. Currently, liners are used for their therapeutic effect and/or to seal the dentinal tubules against the ingress of microorganisms or their by-products at the restoration–tooth interface.4,9 A variety of dental materials have been introduced as liners to provide pulp tissue protection from irritants related to the restorative procedure. The tradi- tional lining materials include calcium hydroxide, glass ionomer, and resin-modified glass ionomers (RMGIs). Calcium hydroxide has been considered as gold standard Correspondence: Naji Ziad Arandi Faculty of Dentistry, The Arab for a long time and enjoys the greatest popularity among general dentists. In clinical American University, PO Box 240, Jenin, practice, calcium hydroxide has been reported as liner of choice in patients with deep 13 Zababdeh, Palestine Tel +972 59 812 6111 cavities.10–12 This review aims to integrate the literature on calcium hydroxide liners Email [email protected] to provide the general dentist with a comprehensive overview that facilitates a better submit your manuscript | www.dovepress.com Clinical, Cosmetic and Investigational Dentistry 2017:9 67–72 67 Dovepress © 2017 Arandi. This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms. http://dx.doi.org/10.2147/CCIDE.S141381 php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php). Arandi Dovepress understanding of the material and its clinical application in u­ sually do not have sufficient thickness, hardness, or strength operative dentistry. to be used alone in a deep cavity. Similarly, Heymann et al3 defined liners as suspensions or dispersions of zinc oxide, Review calcium hydroxide, or RMGI that can be applied to a tooth The definition of a “liner” surface in a relatively thin film. Anusavice et al19 stated that The definition of liners itself has been a source of confusion a cavity liner is a material that is used to coat the bottom of a in dental literature. Marzouk et al13 defined cavity liners as prepared cavity to protect the pulp; it is applied in a thin layer film-forming materials that carry therapeutic agents, which and usually contains calcium hydroxide or mineral trioxide create their greater film thickness (up to 25 µm) and usu- aggregate (MTA); it also includes certain glass ionomer ally applied to dentine only. Ferracane14 described a liner as cements used as intermediate layers between tooth structure material that is applied in a thin layer to seal the dentine on and composite restorative material. the floor and walls of the cavity against the influx of bac- It is important to distinguish between two terms “liners” teria or irritants from restorative procedures. In 1994, The and “suspension liners”. Both terms should not be used Journal of Operative Dentistry published a letter submitted synonymously. Liners (previously referred to as low-strength by Summit15 in which he enlisted cavity liners, varnishes, bases or cement liners or subbases) are materials placed in and resin-bonding agents as subcategories of cavity sealers. deep portions of the cavity preparations that harden when He proposed a definition of a cavity liner as a cement or mixed to form a cement layer (100–500 μm) usually with resin coating with minimal thickness (usually