Investigating the Effects of Heated Tobacco Products on Periodontal Healing: Insights From In Vivo and In Vitro Experiments

This study aimed to investigate the effects of heated tobacco product extract (HTPE) on periodontal healing. HTPE and conventional cigarette smoke extract (CSE) were prepared following a puff protocol. C57BL/6 mice were divided into HTPE, CSE, and control groups. Each solution was intraperitoneally administered for three days. Seven days after ligature placement in the maxillary second molar, alveolar bone resorption was assessed. Bone levels after ligature removal were also assessed. In vitro, human gingival fibroblasts-1 (HGF-1) were cultured with HTPE or CSE for 24 hours. Cell proliferation, migration, and morphology were evaluated, and expressions of genes related to cell migration were also assessed. HTPE and CSE induced significantly greater bone resorption compared with the control, and bone recovery in both groups was reduced. While HTPE had no significant impact on the proliferation of HGF-1, CSE suppressed it. Both HTPE and CSE significantly inhibited cell migration. In the HTPE group, actin filaments in HGF-1 were more pronounced compared with the control, and matrix metalloproteinase-1 (MMP-1) and matrix metalloproteinase-3 (MMP-3) gene expressions were significantly increased. The suppressed cell migration may be attributed in part to the regulation of extracellular matrix remodeling. The results of this study suggest that HTPE impairs periodontal healing, although the extent of this effect may differ from that of CSE.