Effect of oral environment on contemporary orthodontic materials and its clinical implications

Abstract

Contemporary orthodontics entails using advanced materials and devices, simplifying the process of tooth movement. It is well documented that orthodontic materials are subjected to various fluctuations and stresses in the oral environment, such as salivary pH, dietary habits, temperature changes, and masticatory loads. These changes reduce bonding materials’ longevity, plasticize resin polymers, and reduce elastic properties. In addition, the corrosion of orthodontic appliances in the oral environment has concerned clinicians for some time. This is focused on two principal issues: whether corrosion products are absorbed into the body and cause either localized or systemic effects, and the results of corrosion on the physical properties and the clinical performance of orthodontic appliances. Recently, another major concern is the potential release of bisphenol-A from materials containing polymers such as thermoplastic aligners and resins, which is known to induce xenoestrogenicity and cytotoxicity when the tissue level exceeds the daily recommended intake. However, most of these findings are based on in vitro studies that suffer from serious drawbacks such as failure to replicate the exact oral environment and process during orthodontic treatment. Therefore, developing clinically relevant methods should be the goal of future research related to the aging of orthodontic materials. The purpose of this review is to outline the impact of the oral environment on contemporary orthodontic materials.

Color and Chemical Stability of 3D-Printed and Thermoformed Polyurethane-Based Aligners

“…The CIELab* color system is widely endorsed for assessing color changes in dentistry, as it reflects human perception [47]. It is generally agreed among researchers that color alterations with a ∆E* value of 3.7 or higher, as measured by a spectrophotometer, are noticeable to the naked eye or clinically unacceptable [48,49]. Therefore, in this study, any color change values below 3.7 were deemed satisfactory, which was present only in Invisalign after 7 days of immersion in Coca-Cola, and ClearCorrect in black tea and Coca-Cola.…”

Role of Topical and Systemic Medications in Orthodontics: A Review

“…Bone accretion and resorption refer to the changes that occur in the intervening bone tissue next to the shifting tooth. Resorption of bone is a procedure that occurs when osteoclasts break apart the connective tissue inside bones and liberate minerals into the circulation, whereas the deposition of bones is the procedure by which osteoblasts create fresh bone matrix [3,4].…”