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INTRODUCTION: The growing demand for orthodontic braces among Malaysians has led to the development of fake braces. These fake braces services are illegal and their brackets are reported to be of inferior quality. Fake braces are constantly being exposed to the saliva intraorally, hence they are susceptible to corrosion. This study was conducted to investigate the release of metal ions as a result of corrosion from standard and fake orthodontic braces immersed in artificial saliva of different pH. MATERIALS AND METHODS: A total of six different types of brackets (three from standard and three from fake braces) were immersed in containers containing 5 mL of artificial saliva of pH 4.9 and pH 7.8. The samples were collected for analysis on day 1, day 14, and day 28 using Inductively-Coupled Plasma Mass Spectrometry (ICPMS) to evaluate the amount of metal ion released. Statistical analysis was performed to isolate the significant difference of metal ions released between two types of braces in different pH solutions. RESULTS: The release of aluminum, nickel, chromium, manganese and copper were observed and analyzed. Fake braces released the highest concentration of chromium, manganese, and nickel ions in both artificial saliva as compared to standard braces. Brackets immersed in pH 4.9 released a higher number of ions compared to pH 7.8. CONCLUSION: This study showed that fake braces released the highest concentration of metal ions as compared to standard braces. Both time and pH influenced the release of metal ions from orthodontic brackets.

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The aim of this study was to determine the influence of different morphological lip shape during lip movement. Method: A sample of 80 individuals with three-dimensional facial images at rest and during speech were recorded. Subjects were asked to pronounce four bilabial words in a relaxed manner and scanned using the 3dMDFace™ Dynamic System at 48 frames per second. Six lip landmarks were identified at rest and the landmark displacement vectors for the frame of maximal lip movement for all six visemes were recorded. Principal component analysis was applied to isolate relationship between lip traits and their registered coordinates. Eight specific resting morphological lip traits were identified for each individual. The principal component (PC) scores for each viseme were labelled by lip morphological trait and were graphically visualized as ellipses to discriminate any differences in lip movement. Results: The first five PCs accounted for up to 95% of the total variance in lip shape during movement, with PC1 accounting for at least 38%. There was no clear discrimination between PC1, PC2 and PC3 for any of the resting morphological lip traits. Conclusion: Lip shapes during movement are more uniform between individuals and resting morphological lip shape does not influence movement of the lips.

The endodontic-orthodontic interface is not well understood due to the limited scientific literature on the topic. This article aims to provide an overview of the orthodontic treatment and the risk of root resorption, the effects of orthodontic tooth movement on dental pulp and endodontically treated teeth, the role of orthodontics in endodontic-restorative treatment planning, and interdisciplinary patient management. Articles published in English from 1982 to 2021 were searched manually from google scholar using keywords ‘endodontic-orthodontic interface’ and ‘endodontic-orthodontic interrelationship’. Another search engine was MEDLINE/PubMed database using keywords ‘endodontics AND orthodontics’, ‘orthodontic tooth movement AND dental pulp’, 'orthodontic tooth movement AND endodontic treatment' and ‘orthodontics AND dental trauma’. Other relevant articles were obtained from the references of the selected papers. Alterations to the dental pulp following orthodontic tooth movement can be histologic and/or cell biological reactions as well as the increased response threshold to pulp sensibility tests. However, the occurrence of root resorption is complex and multifactorial, and can be linked to individual variation, genetic predisposition and orthodontic treatment-related factors. Endodontically treated teeth can move as readily and respond similarly to orthodontic forces as vital teeth, however with inadequate endodontic treatment, the risk of apical inflammation and bone destruction following orthodontic tooth movement is increased. Dental treatment that involves endodontic and orthodontic specialities should be carefully planned according to the individual case, taking into consideration the skills and experience of the clinicians while applying interdisciplinary patient management and available scientific data.