ABSTRACT Root resorption is a shortening of root dentine which occurs physiologically in deciduous teeth. The present study aimed to quantify dentine sialophosphoprotein (DSPP), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) in gingival crevicular fluid (GCF) during the physiological process of root resorption of deciduous teeth. A cross-sectional study was conducted with 25 children aged between 4 and 10 years old. GCF was collected from the gingival sulcus using periopaper strips from the upper first deciduous molar (n = 45). The samples were divided equally into three groups, no resorption (R0), moderate resorption (RM) and severe resorption (RS), based on the existing radiographs taken. The GCF samples were then analysed using an enzyme-linked immunosorbent assay (ELISA) kit to determine the DSPP concentration levels and BioAssays System kit for AST and LDH. One-way ANOVA was used to determine the statistical differences between the means of the DSPP, AST and LDH concentration level in the three groups. A difference was considered significant when p < 0.05. High concentration levels of DSPP were significantly noted in RS (p < 0.05), compared to RM and R0. AST also portrayed significant high activity level (p < 0.05) similar to DSPP but LDH showed no significant changes between groups (p > 0.05). The high quantification of DSPP and AST levels in the severe and moderately resorbed roots indicated the potential use of this protein as a biomarker for detecting moderate-severe stages of root resorption.
Root Resorption ; Gingival Crevicular Fluid ; Dentin ; Aspartate Aminotransferases ; Lactate Dehydrogenases

Retention phase is fundamental in orthodontic treatment. Around 70% of patients are subjected to relapse postorthodontic treatment. The risk of relapse can be minimized by prescribing a retainer suitable to a patient’s pre-treatment clinical condition and based on retention characteristics of retainers. When removable retainers are prescribed, responsibility of maintaining tooth stability lies on patients. Recent idea has been proposed that removable retainer should be worn indefinitely in order to maintain the treatment result. Therefore, the understanding of retention characteristics of removable retainers is important for promoting patient compliance and satisfaction. This article focuses on reviewing the use of removable retainers in relation to preferences among clinicians, patient acceptability, effectiveness, compliance, as well as retention regimes. An electronic search was conducted in the PubMed/MEDLINE, ScienceDirect and Scopus database. The search was performed up to June 2020 using a variety of keywords including orthodontic retainers, Hawley, vacuum formed and retention. Among the 248 publications that were initially searched, total of 56 publications were finally included. Twenty-seven were observational (6 prospective; 16 cross-sectional, 4 retrospective, and 1 case series), fourteen experimental, fourteen review articles, and one opinion piece. Although quite a number of reviews on removable retainers were available, several significant papers have been published recently. Furthermore, a guideline on retention regime is warranted.