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The key characteristic (KCs) framework has been used previously to assess the carcinogenicity and cardiotoxicity of various chemical and pharmacological agents. Here, the 12 KCs of cardiotoxicity are used to evaluate the previously reported cardiotoxicity of phenanthrene (Phe), a tricyclic polycyclic aromatic hydrocarbon (PAH), and major component of fossil fuel-derived air pollution. Phe is a semi-volatile pollutant existing in both the gas phase and particle phase through adsorption onto or into particulate matter (PM). Phe can translocate across the airways and gastrointestinal tract into the systemic circulation, enabling body-wide effects. Our evaluation based on a comprehensive literature review, indicates Phe exhibits 11 of the 12 KCs for cardiotoxicity. These include adverse effects on cardiac electromechanical performance, the vasculature and endothelium, immunomodulation and oxidative stress, and neuronal and endocrine control. Environmental agents that have similarly damaging effects on the cardiovascular system are heavily regulated and monitored, yet globally there is no air quality regulation specific for PAHs like Phe. Environmental monitoring of Phe is not the international standard with benzo[a]pyrene being frequently used as a proxy despite the two PAH species exhibiting significant differences in sources, concentration variations and toxic effects. The evidence summarised in this evaluation highlights the need to move away from proxied PAH measurements and develop a monitoring network capable of measuring Phe concentration. It also stresses the need to raise awareness amongst the medical community of the potential cardiovascular impact of PAH exposure. This will allow the production of mitigation strategies and possibly the development of new policies for the protection of the societal groups most vulnerable to cardiovascular disease., Competing Interests: Declaration of Competing Interest Authors have no competing interests to declare., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Introduction: This study was designed to evaluate the long-term prevalence of gingival recession after orthodontic tooth movements, focusing on the effects of mandibular incisor proclination and expansion of maxillary posterior teeth., Methods: Records of 205 patients (162 female, 43 male) were obtained from 2 private practice orthodontists. Using pretreatment (age, 14.0 ± 5.9 years) and posttreatment (age, 16.5 ± 6.0 years) lateral cephalograms and dental models, mandibular incisor proclination and maxillary arch widths were measured. Gingival recession was measured based on posttreatment and postretention (age, 32.3 ± 8.5 years) intraoral photographs and models. Associations between tooth movements and gingival recession were evaluated statistically., Results: Only 5.8% of teeth exhibited recession at the end of orthodontic treatment (only 0.6% had recession >1 mm). After retention, 41.7% of the teeth showed recession, but the severity was limited (only 7.0% >1 mm). There was no relationship between mandibular incisor proclination during treatment and posttreatment gingival recession. Incisors that finished treatment angulated (IMPA) at 95° or greater did not show significantly more recession than did those that finished less than 95°. There were weak positive correlations (r = 0.17-0.41) between maxillary arch width increases during treatment and posttreatment recession., Conclusions: Orthodontic treatment is not a major risk factor for the development of gingival recession. Although greater amounts of maxillary expansion during treatment increase the risks of posttreatment recession, the effects are minimal., (Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)