TG and periodontitis: It has been shown that THS regulates bone metabolism independently of thyroid hormones, including the function of osteoblasts and osteoclasts.34A recentin vitrostudy observed that THS could inhibit the osteogenic differentiation of periodontal ligament stem cells (PDLSCs) and thus negatively affect periodontitis prevalence and outcome.34The conclusion of the same study was that reducing serum TSH levels may improve the osteogenic differentiation of PDLSCs.