Periodontitis is an infectious disease caused by an imbalance between the local microbiota and host immune response. Epidemiologically, periodontitis is closely related to the occurrence, development, and poor prognosis of T2D and is recognized as a potential risk factor for T2D. In recent years, increasing attention has been given to the role of the virulence factors produced by disorders of the subgingival microbiota in the pathological mechanism of T2D, including islet β-cell dysfunction and insulin resistance (IR). However, the related mechanisms have not been well summarized. This review highlights periodontitis-derived virulence factors, reviews how these stimuli directly or indirectly regulate islet β-cell dysfunction. The mechanisms by which IR is induced in insulin-targeting tissues (the liver, visceral adipose tissue, and skeletal muscle) are explained, clarifying the influence of periodontitis on the occurrence and development of T2D. In addition, the positive effects of periodontal therapy on T2D are overviewed. Finally, the limitations and prospects of the current research are discussed. In summary, periodontitis is worthy of attention as a promoting factor of T2D. Understanding on the effect of disseminated periodontitis-derived virulence factors on the T2D-related tissues and cells may provide new treatment options for reducing the risk of T2D associated with periodontitis.

Oral cancer is a common malignant tumor of the head and neck, and surgery combined with radiotherapy and chemotherapy is the primary treatment modality. However, a positive resection margin that may lead to recurrence after surgery has always been a critical issue to address. Furthermore, radiotherapy and chemotherapy also have shortcomings such as resistance to chemotherapy and radiation, lack of targeting, and severe side effects. Therefore, exploring new methods of tumor surgical navigation and tumor treatment is of great significance for oral cancer. Although, the emerging near-infrared II (NIR-II, 1,000–1,700 nm) region fluorescent imaging has revolutionized surgical navigation, a high tumor-targeting fluorescent probe remains lacking. Furthermore, while emerging photothermal therapy (PTT) can overcome chemoradiotherapy’s shortcomings and achieve precise treatment of tumors, its clinical application is still limited by the lack of high photothermal conversion efficiency, high photothermal stability, and highly penetrating materials. Herein, a NIR-II dye SQ890 is developed for tumor imaging and PTT of oral cancer. By assembling into nanoparticles (NPs) and being modified with epithelial growth factor receptor (EGFR)-targeting peptides GE11, SQ890 NPs-Pep can specifically accumulate in tumor sites via active targeting, and realize photoacoustic/NIR-II fluorescence dual-modality imaging-guided PTT of oral cancer.