Vaping, heated tobacco, and periodontal health: a systematic review of their effects on inflammation, microbiota, and non-surgical therapy response

Abstract

Background:The increasing use of electronic cigarettes and heated tobacco products has raised concerns regarding their potential effects on periodontal health. The objective of this systematic review was to assess the impact of these alternative nicotine delivery systems on periodontal inflammation, oral microbiota, and outcomes of non-surgical periodontal therapy.

Methods: A comprehensive literature search was conducted in PubMed, Web of Science, and Scopus, in accordance with PRISMA guidelines.

Results: The findings indicate that although electronic cigarettes and heated tobacco products may reduce exposure to certain harmful constituents compared with conventional cigarettes, they are not free of adverse effects. Their use has been associated with increased levels of pro-inflammatory cytokines, reduced anti-inflammatory mediators, delayed periodontal healing, and alterations in oral microbiota composition, which may contribute to the progression of periodontal disease. These biological changes may negatively influence the response to non-surgical periodontal therapy.

Discussion: From a clinical perspective, individuals using electronic cigarettes or heated tobacco products tend to exhibit less favorable treatment outcomes, often comparable to those observed in conventional cigarette smokers. Despite being promoted as harm-reduction alternatives, current evidence suggests that electronic cigarettes and heated tobacco products still pose significant risks to periodontal tissues. Overall, the available biological and clinical evidence supports the need for further investigation into the underlying mechanisms of tissue damage and reinforces the importance of promoting complete smoking cessation, including avoidance of electronic cigarettes and heated tobacco products, to preserve long-term oral health.

Keywords

vaping / cigarette / smoking / e-cigarette / periodontitis / electronic cigarette / oral mucosal health

References

[1] Vansickel AR, Cobb CO, Weaver MF, Eissenberg TE. A clinical laboratory model for evaluating the acute effects of electronic “cigarettes”: nicotine delivery profile and cardiovascular and subjective effects. Cancer Epidemiol Biomarkers Prev. 2010; 19: 1945-53.

[2] Cuadra GA, Smith MT, Nelson JM, Loh EK, Palazzolo DL. A Comparison of Flavorless Electronic Cigarette-Generated Aerosol and Conventional Cigarette Smoke on the Survival and Growth of Common Oral Commensal Streptococci. Int J Environ Res Public Health. 2019; 16: 1669.

[3] Overbeek DL, Kass AP, Chiel LE, Boyer EW, Casey AMH. A review of toxic effects of electronic cigarettes/vaping in adolescents and young adults. Crit Rev Toxicol. 2020; 50: 531-8.

[4] D’Mello K, Driezen P, East KA, Fong GT, Hammond D. Trends in the Use of Vaping Products and Other Smoking Cessation Methods Among Adults Who Attempt to Stop Smoking: Findings From the International Tobacco Control Four-Country Smoking and Vaping Surveys (2016-2020). Nicotine Tob Res. 2025; 27: 2213-22.

[5] Ganesan SM, Dabdoub SM, Nagaraja HN, Scott ML, Pamulapati S, Berman ML, et al. Adverse effects of electronic cigarettes on the disease-naive oral microbiome. Sci Adv. 2020; 6: eaaz0108.

[6] Ogunwale MA, Li M, Ramakrishnam Raju MV, Chen Y, Nantz MH, Conklin DJ, et al. Aldehyde Detection in Electronic Cigarette Aerosols. ACS Omega. 2017; 2: 1207-14.

[7] Williams M, Bozhilov KN, Talbot P. Analysis of the elements and metals in multiple generations of electronic cigarette atomizers. Environ Res. 2019; 175: 156-66.

[8] O’Brien D, Long J, Quigley J, Lee C, McCarthy A, Kavanagh P. Association between electronic cigarette use and tobacco cigarette smoking initiation in adolescents: a systematic review and meta-analysis. BMC Public Health. 2021; 21: 954.

[9] Soneji S, Barrington-Trimis JL, Wills TA, Leventhal AM, Unger JB, Gibson LA, et al. Association Between Initial Use of e-Cigarettes and Subsequent Cigarette Smoking Among Adolescents and Young Adults: A Systematic Review and Meta-analysis. JAMA Pediatr. 2017; 171: 788-97.

[10] Atuegwu NC, Perez MF, Oncken C, Thacker S, Mead EL, Mortensen EM. Association between Regular Electronic Nicotine Product Use and Self-reported Periodontal Disease Status: Population Assessment of Tobacco and Health Survey. Int J Environ Res Public Health. 2019; 16: 1263.

[11] Chido-Amajuoyi OG, Omega-Njemnobi O, Okoli C, Ozigbu C, Okoroafor I, Anikpezie N, et al. Association of combustible and non-combustible tobacco use with clinically diagnosed adverse oral health outcomes among US adults, National Health and Nutrition Examination Survey (2009-2014). Drug Alcohol Rev. 2022; 41: 1521-7.

[12] Kosmider L, Sobczak A, Fik M, Knysak J, Zaciera M, Kurek J, et al. Carbonyl compounds in electronic cigarette vapors: effects of nicotine solvent and battery output voltage. Nicotine Tob Res. 2014; 16: 1319-26.

[13] Perrine CG, Pickens CM, Boehmer TK, King BA, Jones CM, DeSisto CL, et al.; Lung Injury Response Epidemiology/Surveillance Group. Characteristics of a Multistate Outbreak of Lung Injury Associated with E-cigarette Use, or Vaping - United States, 2019. MMWR Morb Mortal Wkly Rep. 2019; 68: 860-4.

[14] Gu J, Gong D, Wang Y, Feng T, Zhang J, Hu S, et al. Chronic exposure to IQOS results in impaired pulmonary function and lung tissue damage in mice. Toxicol Lett. 2023; 374: 1-10.

[15] Bulmanski Z, Brady M, Stoute D, Lallier TE. Cigarette smoke extract induces select matrix metalloproteinases and integrin expression in periodontal ligament fibroblasts. J Periodontol. 2012; 83: 787-96.

[16] Johnson GK, Hill M. Cigarette smoking and the periodontal patient. J Periodontol. 2004; 75: 196-209.

[17] BinShabaib M, ALHarthi SS, Akram Z, Khan J, Rahman I, Romanos GE, et al. Clinical periodontal status and gingival crevicular fluid cytokine profile among cigarette-smokers, electronic-cigarette users and never-smokers. Arch Oral Biol. 2019; 102: 212-7.

[18] Ali D, Kuyunov I, Baskaradoss JK, Mikami T. Comparison of periodontal status and salivary IL-15 and -18 levels in cigarette-smokers and individuals using electronic nicotine delivery systems. BMC Oral Health. 2022; 22: 655.

[19] Chopyk J, Bojanowski CM, Shin J, Moshensky A, Fuentes AL, Bonde SS, et al. Compositional Differences in the Oral Microbiome of E-cigarette Users. Front Microbiol. 2021; 12: 599664.

[20] Sancilio S, Gallorini M, Cataldi A, di Giacomo V. Cytotoxicity and apoptosis induction by e-cigarette fluids in human gingival fibroblasts. Clin Oral Investig. 2016; 20: 477-83.

[21] Izquierdo-Condoy JS, Naranjo-Lara P, Morales-Lapo E, Hidalgo MR, Tello-De-la-Torre A, Vásconez-Gonzáles E, et al. Direct health implications of e-cigarette use: a systematic scoping review with evidence assessment. Front Public Health. 2024; 12: 1427752.

[22] Schripp T, Markewitz D, Uhde E, Salthammer T. Does e-cigarette consumption cause passive vaping? Indoor Air. 2013; 23: 25-31.

[23] Mišković I, Kuiš D, Špalj S, Pupovac A, Mohar-Vitezić B, Prpić J. Does Exposure to Burning and Heated Tobacco Affect the Abundance of Perio-Pathogenic Species in the Subgingival Biofilm? Appl Sci. 2024; 14: 4824.

[24] Hellyer P. Does nicotine damage oral health? Br Dent J. 2019; 227: 275.

[25] McCormack JC, Agbor Epse Muluh E, Mo Y, McLeod SC, Turner S, Ghelot DS, et al. Does vaping affect the taste and smell perception? An exploratory study with New Zealand young adults. Appetite. 2024; 195: 107236.

[26] E Cigarettes, Vaping and Chairside Education [Internet]. Endeavor Business Media, LLC.; c2026 [cited 2024 Nov 5]. Available from: https://www.rdhmag.com/home/article/16409913/e-cigarettes-vaping-and-chairside-education

[27] Catala-Valentin A, Bernard JN, Caldwell M, Maxson J, Moore SD, Andl CD. E-Cigarette Aerosol Exposure Favors the Growth and Colonization of Oral Streptococcus mutans Compared to Commensal Streptococci. Microbiol Spectr. 2022; 10: e0242121.

[28] Sahu R, Shah K, Malviya R, Paliwal D, Sagar S, Singh S, et al. E-Cigarettes and Associated Health Risks: An Update on Cancer Potential. Adv Respir Med. 2023; 91: 516-31.

[29] Harrell PT, Simmons VN, Piñeiro B, Correa JB, Menzie NS, Meltzer LR, et al. E-cigarettes and expectancies: why do some users keep smoking? Addiction. 2015; 110: 1833-43.

[30] Zhang Y, He J, He B, Huang R, Li M. Effect of tobacco on periodontal disease and oral cancer. Tob Induc Dis. 2019; 17: 40.

[31] Akram Z, Javed F, Vohra F. Effect of waterpipe smoking on peri-implant health: A systematic review and meta-analysis. J Investig Clin Dent. 2019; 10: e12403.

[32] Zhao T, Shu S, Guo Q, Zhu Y. Effects of Design Parameters and Puff Topography on Heating Coil Temperature and Mainstream Aerosols in Electronic Cigarettes. Atmos Environ. 2016; 134: 61-9.

[33] Laforgia A, Inchingolo AD, Piras F, Colonna V, Giorgio RV, Carone C, et al. Therapeutic Strategies and Genetic Implications for Periodontal Disease Management: A Systematic Review. Int J Mol Sci. 2024; 25: 7217.

[34] Isik Andrikopoulos G, Farsalinos K, Poulas K. Electronic Nicotine Delivery Systems (ENDS) and Their Relevance in Oral Health. Toxics. 2019; 7: 61.

[35] Amaral AL, Lwaleed BA, Andrade SA. Electronic nicotine delivery systems (ENDS): a strategy for smoking cessation or a new risk factor for oral health? Evid Based Dent. 2023; 24: 188-9.

[36] El Dib R, Suzumura EA, Akl EA, Gomaa H, Agarwal A, Chang Y, et al. Electronic Nicotine Delivery Systems and/or Electronic Non-Nicotine Delivery Systems for Tobacco Smoking Cessation or Reduction: A Systematic Review and Meta-Analysis. BMJ Open. 2017; 7: e012680.

[37] Williams M, Bozhilov K, Ghai S, Talbot P. Elements including metals in the atomizer and aerosol of disposable electronic cigarettes and electronic hookahs. PLoS One. 2017; 12: e0175430.

[38] Sutton JD, Salas Martinez ML, Gerkovich MM. Environmental Tobacco Smoke and Periodontitis in United States Non-Smokers, 2009 to 2012. J Periodontol. 2017; 88: 565-74.

[39] Soneji S. Errors in Data Input in Meta-analysis on Association Between Initial Use of e-Cigarettes and Subsequent Cigarette Smoking Among Adolescents and Young Adults. JAMA Pediatr. 2018; 172: 92-3.

[40] Pesce P, Menini M, Ugo G, Bagnasco F, Dioguardi M, Troiano G. Evaluation of periodontal indices among non-smokers, tobacco, and e-cigarette smokers: a systematic review and network meta-analysis. Clin Oral Investig. 2022; 26: 4701-14.

[41] Znyk M, Jurewicz J, Kaleta D. Exposure to Heated Tobacco Products and Adverse Health Effects, a Systematic Review. Int J Environ Res Public Health. 2021; 18: 6651.

[42] Goniewicz ML, Gawron M, Smith DM, Peng M, Jacob P 3rd, Benowitz NL. Exposure to Nicotine and Selected Toxicants in Cigarette Smokers Who Switched to Electronic Cigarettes: A Longitudinal Within-Subjects Observational Study. Nicotine Tob Res. 2017; 19: 160-7.

[43] Doya K, Imamura K, Mori S, Nakane-Koyachi S, Kokubu E, Ishihara K, Saito A. Investigating the Effects of Heated Tobacco Products on Periodontal Healing: Insights From In Vivo and In Vitro Experiments. Cureus. 2025; 17: e80733.

[44] Pouly S, Ng WT, Blanc N, Hession P, Zanetti F, Battey JND, et al. Effect of switching from cigarette smoking to the use of the tobacco heating system on periodontitis treatment outcome: Periodontal parameter results from a multicenter Japanese study. Front Dent Med. 2022; 3: 915079.

[45] Alwafi AA, Abuljadayel LW. Oral Health of the Electronic Cigarette Smokers: A Systematic Review. J Pharm Bioallied Sci. 2024; 16: S4331-8.

[46] Lallier TE, Moylan JT, Maturin E. Greater Sensitivity of Oral Fibroblasts to Smoked Versus Smokeless Tobacco. J Periodontol. 2017; 88: 1356-65.

[47] Ebersole J, Samburova V, Son Y, Cappelli D, Demopoulos C, Capurro A, et al. Harmful chemicals emitted from electronic cigarettes and potential deleterious effects in the oral cavity. Tob Induc Dis. 2020; 18: 41.

[48] Travis N, Knoll M, Cadham CJ, Cook S, Warner KE, Fleischer NL, et al. Health Effects of Electronic Cigarettes: An Umbrella Review and Methodological Considerations. Int J Environ Res Public Health. 2022; 19: 9054.

[49] Auer R, Concha-Lozano N, Jacot-Sadowski I, Cornuz J, Berthet A. Heat-Not-Burn Tobacco Cigarettes: Smoke by Any Other Name. JAMA Intern Med. 2017; 177: 1050-2.

[50] Jensen RP, Luo W, Pankow JF, Strongin RM, Peyton DH. Hidden formaldehyde in e-cigarette aerosols. N Engl J Med. 2015; 372: 392-4.

[51] Ratajczak A, Feleszko W, Smith DM, Goniewicz M. How close are we to definitively identifying the respiratory health effects of e-cigarettes? Expert Rev Respir Med. 2018; 12: 549-56.

[52] Robbins J, Ali K. How do periodontal indices compare among non-smokers, tobacco and e-cigarette smokers? Evid Based Dent. 2022; 23: 116-7.

[53] Ureña JF, Ebersol LA, Silakov A, Elias RJ, Lambert JD. Impact of Atomizer Age and Flavor on In Vitro Toxicity of Aerosols from a Third-Generation Electronic Cigarette against Human Oral Cells. Chem Res Toxicol. 2020; 33: 2527-37.

[54] Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ. 2021; 372: n71.

[55] Xu F, Aboseria E, Janal MN, Pushalkar S, Bederoff MV, Vasconcelos R, et al. Comparative Effects of E-Cigarette Aerosol on Periodontium of Periodontitis Patients. Front Oral Health. 2021; 2: 729144.

[56] Shah C, Holtfreter B, Hughes FJ, Nibali L. Retrospective exploratory study of smoking status and e-cigarette use with response to non-surgical periodontal therapy. J Periodontol. 2023; 94: 41-54.

[57] Kumar S, Shlossman M. Does e-cigarette use affect response to non-surgical periodontal therapy? Evid Based Dent. 2023; 24: 179-80.

[58] Holliday R, Preshaw PM, Ryan V, Sniehotta FF, McDonald S, Bauld L, et al. A feasibility study with embedded pilot randomised controlled trial and process evaluation of electronic cigarettes for smoking cessation in patients with periodontitis. Pilot Feasibility Stud. 2019; 5: 74.

[59] Karaaslan F, Dikilitaş A, Yiğit U. The effects of vaping electronic cigarettes on periodontitis. Aust Dent J. 2020; 65: 143-9.

[60] Kiiun I, Soltys O, Kilmukhametova Y, Drozda I, Dronyk I, Bukach O. Dynamics of Urease and Lysozyme Activity in the Oral Fluid and the Degree of Oral Dysbiosis in Persons with Periodontal Tissue Diseases Against the Background of E-Cigarette Smoking. Periodontology. 2023; 27: 39-44.

[61] Akram Z, Aati S, Alrahlah A, Vohra F, Fawzy A. Longitudinal evaluation of clinical, spectral and tissue degradation biomarkers in progression of periodontitis among cigarette and electronic cigarette smokers. J Dent. 2021; 109: 103678.

[62] ArRejaie AS, Al-Aali KA, Alrabiah M, Vohra F, Mokeem SA, Basunbul G, et al. Proinflammatory cytokine levels and peri-implant parameters among cigarette smokers, individuals vaping electronic cigarettes, and non-smokers. J Periodontol. 2019; 90: 367-74.

[63] ALHarthi SS, BinShabaib M, Akram Z, Rahman I, Romanos GE, Javed F. Impact of cigarette smoking and vaping on the outcome of full-mouth ultrasonic scaling among patients with gingival inflammation: a prospective study. Clin Oral Investig. 2019; 23: 2751-8.

[64] Mišković I, Kuiš D, Špalj S, Pupovac A, Prpić J. Periodontal Health Status in Adults Exposed to Tobacco Heating System Aerosol and Cigarette Smoke vs. Non-Smokers: A Cross-Sectional Study. Dent J (Basel). 2024; 12: 26.

[65] Pouly S, Ng WT, Benzimra M, Soulan A, Blanc N, Zanetti F, et al. Effect of Switching to the Tobacco Heating System Versus Continued Cigarette Smoking on Chronic Generalized Periodontitis Treatment Outcome: Protocol for a Randomized Controlled Multicenter Study. JMIR Res Protoc. 2021; 10: e15350.

[66] Al-Hamoudi N, Alsahhaf A, Al Deeb M, Alrabiah M, Vohra F, Abduljabbar T. Effect of scaling and root planing on the expression of anti-inflammatory cytokines (IL-4, IL-9, IL-10, and IL-13) in the gingival crevicular fluid of electronic cigarette users and non-smokers with moderate chronic periodontitis. J Periodontal Implant Sci. 2020; 50: 74-82.

[67] ALHarthi SS, BinShabaib MS, Ahmed HB, Mehmood A, Khan J, Javed F. Comparison of peri-implant clinical and radiographic inflammatory parameters among cigarette and waterpipe (narghile) smokers and never-smokers. J Periodontol. 2018; 89: 213-8.

[68] Camoni N, Conti G, Esteves-Oliveira M, Carvalho TS, Roccuzzo A, Cagetti MG, et al. Electronic Cigarettes, Heated Tobacco Products, and Oral Health: A Systematic Review and Meta-Analysis. Appl Sci. 2023; 13: 9654.

[69] Amaral AL, da Costa Andrade PA, Lwaleed BA, Andrade SA. Impacts of smoking on oral health-what is the role of the dental team in smoking cessation? Evid Based Dent. 2023; 24: 186-7.

[70] Charde P, Ali K, Hamdan N. Effects of e-cigarette smoking on periodontal health: A scoping review. PLOS Glob Public Health. 2024; 4: e0002311.

[71] Kumar N, Janmohamed K, Jiang J, Ainooson J, Billings A, Chen GQ, et al. Tobacco cessation in low- to middle-income countries: A scoping review of randomized controlled trials. Addict Behav. 2021; 112: 106612.

[72] Moore D. Is Nicotine Damaging to Oral Tissues? Evid Based Dent. 2020; 21: 32-3.

[73] Alkattan R, Tashkandi N, Mirdad A, Ali HT, Alshibani N, Allam E. Effects of Electronic Cigarettes on Periodontal Health: A Systematic Review and Meta-Analysis. Int Dent J. 2025; 75: 2014-24.

[74] Aldakheel FM, Alduraywish SA, Jhugroo P, Jhugroo C, Divakar DD. Quantification of pathogenic bacteria in the subgingival oral biofilm samples collected from cigarette-smokers, individuals using electronic nicotine delivery systems and non-smokers with and without periodontitis. Arch Oral Biol. 2020; 117: 104793.

[75] Williams M, Villarreal A, Bozhilov K, Lin S, Talbot P. Metal and silicate particles including nanoparticles are present in electronic cigarette cartomizer fluid and aerosol. PLoS One. 2013; 8: e57987.

[76] Jankowski M, Brożek GM, Lawson J, Skoczyński S, Majek P, Zejda JE. New ideas, old problems? Heated tobacco products - a systematic review. Int J Occup Med Environ Health. 2019; 32: 595-634.

[77] AlJasser R, Zahid M, AlSarhan M, AlOtaibi D, AlOraini S. The effect of conventional versus electronic cigarette use on treatment outcomes of peri-implant disease. BMC Oral Health. 2021; 21: 480.

[78] Alshibani N, Alssum L, Basudan A, Shaheen M, Alqutub MN, Dahash FA, et al. Non-surgical periodontal therapy with adjunct photodynamic therapy for the management of periodontal inflammation in adults using nicotine-free electronic-cigarette: A randomized control trial. Photodiagnosis Photodyn Ther. 2022; 38: 102820.

[79] Contaldo M, Fusco A, Stiuso P, Lama S, Gravina AG, Itro A, et al. Oral Microbiota and Salivary Levels of Oral Pathogens in Gastro-Intestinal Diseases: Current Knowledge and Exploratory Study. Microorganisms. 2021; 9: 1064.

[80] Santacroce L, Passarelli PC, Azzolino D, Bottalico L, Charitos IA, Cazzolla AP, et al. Oral microbiota in human health and disease: A perspective. Exp Biol Med (Maywood). 2023; 248: 1288-301.

[81] Pryor WA, Stone K. Oxidants in cigarette smoke. Radicals, hydrogen peroxide, peroxynitrate, and peroxynitrite. Ann N Y Acad Sci. 1993; 686: 12-27.

[82] Sundar IK, Yao H, Rahman I. Oxidative stress and chromatin remodeling in chronic obstructive pulmonary disease and smoking-related diseases. Antioxid Redox Signal. 2013; 18: 1956-71.

[83] Aljoghaiman EA, Albrahim A, Aldarisi A, Alsafwani M, Alhalal F. The effect of cigarette and e-cigarette use on periodontal health: A cross-sectional study in Eastern Province, Saudi Arabia. Tob Induc Dis. 2026; 24: 4.

[84] Fatima M, Muhammad Ali F, Ullah R. Popular Trend of Electronic Cigarettes and Their Adverse Effects on Oral Health. Cureus. 2023; 15: e50808.

[85] Adermark L, Galanti MR, Ryk C, Gilljam H, Hedman L. Prospective association between use of electronic cigarettes and use of conventional cigarettes: a systematic review and meta-analysis. ERJ Open Res. 2021; 7: 00976-2020.

[86] Yanagisawa T, Ueno M, Shinada K, Ohara S, Wright FAC, Kawaguchi Y. Relationship of smoking and smoking cessation with oral health status in Japanese men. J Periodontal Res. 2010; 45: 277-83.

[87] Al-Zyoud W, Hajjo R, Abu-Siniyeh A, Hajjaj S. Salivary Microbiome and Cigarette Smoking: A First of Its Kind Investigation in Jordan. Int J Environ Res Public Health. 2019; 17: 256.

[88] Stewart CJ, Auchtung TA, Ajami NJ, Velasquez K, Smith DP, De La Garza R 2nd, et al. Effects of tobacco smoke and electronic cigarette vapor exposure on the oral and gut microbiota in humans: a pilot study. PeerJ. 2018; 6: e4693.

[89] Protano C, Manigrasso M, Avino P, Sernia S, Vitali M. Second-hand smoke exposure generated by new electronic devices (IQOS® and e-cigs) and traditional cigarettes: submicron particle behaviour in human respiratory system. Ann Ig. 2016; 28: 109-12.

[90] Panariello B, Dias Panariello F, Misir A, Barboza EP. An Umbrella Review of E-Cigarettes’ Impact on Oral Microbiota and Biofilm Buildup. Pathogens. 2025; 14: 578.

[91] Alam F, Silveyra P. Sex Differences in E-Cigarette Use and Related Health Effects. Int J Environ Res Public Health. 2023; 20: 7079.

[92] Brandon KO, Simmons VN, Meltzer LR, Drobes DJ, Martínez Ú, Sutton SK, et al. Vaping Characteristics and Expectancies Are Associated with Smoking Cessation Propensity among Dual Users of Combustible and Electronic Cigarettes. Addiction. 2019; 114: 896-906.

[93] Lerner CA, Sundar IK, Yao H, Gerloff J, Ossip DJ, McIntosh S, et al. Vapors produced by electronic cigarettes and e-juices with flavorings induce toxicity, oxidative stress, and inflammatory response in lung epithelial cells and in mouse lung. PLoS One. 2015; 10: e0116732.

[94] Thomas KH, Dalili MN, López-López JA, Keeney E, Phillippo D, Munafò MR, et al. Smoking cessation medicines and e-cigarettes: a systematic review, network meta-analysis and cost-effectiveness analysis. Health Technol Assess. 2021; 25: 1-224.

[95] Williams M, To A, Bozhilov K, Talbot P. Strategies to Reduce Tin and Other Metals in Electronic Cigarette Aerosol. PLoS One. 2015; 10: e0138933.

[96] Saliba NA, El Hellani A, Honein E, Salman R, Talih S, Zeaiter J, et al. Surface Chemistry of Electronic Cigarette Electrical Heating Coils: Effects of Metal Type on Propylene Glycol Thermal Decomposition. J Anal Appl Pyrolysis. 2018; 134: 520-5.

[97] Zhang Q, Wen C. The risk profile of electronic nicotine delivery systems, compared to traditional cigarettes, on oral disease: a review. Front Public Health. 2023; 11: 1146949.

[98] Leigh NJ, Palumbo MN, Marino AM, O’Connor RJ, Goniewicz ML. Tobacco-specific nitrosamines (TSNA) in heated tobacco product IQOS. Tob Control. 2018; 27: s37-8.

[99] Tishchenko OV, Kryvenko LS, Gargina VV. Influence of smoking heating up tobacco products and e-cigarettes on the microbiota of dental plaque. Pol Merkur Lekarski. 2022; 50: 16-20.

[100] Sahni V, Gupta S. The association between second-hand smoke and the periodontal status of children and adolescents. Evid Based Dent. 2022; 23: 106-7.

[101] Bonner E, Chang Y, Christie E, Colvin V, Cunningham B, Elson D, et al. The chemistry and toxicology of vaping. Pharmacol Ther. 2021; 225: 107837.

[102] AlZamil AF, AlQutub MN. The effect of different cigarette smoking levels on gingival crevicular fluid volume and periodontal clinical parameters in Saudi Arabia. Saudi Dent J. 2023; 35: 525-33.

[103] Youssef M, Marzouk T, Abdelsalam H, Malmstrom H, Barmak AB, Fraser D, et al. The effect of electronic cigarette use on peri-implant conditions in men: a systematic review and meta-analysis. Oral Surg Oral Med Oral Pathol Oral Radiol. 2023; 135: 492-500.

[104] Szumilas P, Wilk A, Szumilas K, Karakiewicz B. The Effects of E-Cigarette Aerosol on Oral Cavity Cells and Tissues: A Narrative Review. Toxics. 2022; 10: 74.

[105] Thiem DGE, Donkiewicz P, Rejaey R, Wiesmann-Imilowski N, Deschner J, Al-Nawas B, et al. The impact of electronic and conventional cigarettes on periodontal health-a systematic review and meta-analysis. Clin Oral Investig. 2023; 27: 4911-28.

[106] Shabil M, Khatib MN, Ballal S, Bansal P, Tomar BS, Ashraf A, et al. The impact of electronic cigarette use on periodontitis and periodontal outcomes: a systematic review and meta-analysis. BMC Oral Health. 2024; 24: 1197.