The effect of near-infrared light-assisted photothermal therapy combined with polymer materials on promoting bone regeneration: A systematic review

Bone tissue engineering (BTE) has become a promising method for treating bone defects in recent decades. Polymers are effective materials currently used in the field of BTE due to their diverse characteristics and easy processing performance, which are categorised into natural polymers and synthetic polymers. Photothermal effects produced by near-infrared (NIR) light constitute an effective way to promote osteogenesis, with the advantages of being non-invasive and having high spatial and temporal precision. The main objective of this systematic review was to reveal the current applications of NIR light-assisted photothermal therapy (PTT) with polymer scaffolds as the delivery vehicles for photothermal agents and tissue supports in BTE. The databases collection was completed on October 1, 2021, and a total of 21 relevant studies were finally included. According to the retrieved literatures, we outlined that polymers could be made into various forms, such as coatings, three-dimensional (3D) porous scaffolds, membranes and injectable hydrogels, etc., and that the hyperthermia generated by PTT has a good effect on osteogenesis, as well as anti-tumour, antibacterial and osseointegration around the implants. These findings have revealed that the joint application of BTE polymer scaffolds and NIR light-assisted PTT play a positive role in bone regeneration.