Melatonin in oral implantology: from discovery to therapy

Melatonin, N-acetyl-5-methoxytryptamine, is a derivative of the essential amino acid tryptophan and is produced primarily in the pineal gland in mammals. Known as a regulator of circadian rhythm, it also has physiologic roles in oral medicine and dentistry. Oral cavity is affected by number of conditions such as periodontitis, mucositis, cancers and cytotoxicity from various drugs or biomaterials. Research has suggested that melatonin is effective in treating the aforementioned pathologies. Furthermore, melatonin has been observed to enhance osseointegration and bone regeneration. The aim of this article is to critically analyze and summarize the research focusing on bone metabolism that promotes bone regeneration around dental implants. Dental implants require surface modifications in order to increase their bioactivity prior to their placement in periodontal bone. However, there are several drawbacks of modified implants such as delamination of the bioactive coating, ion leakage and particle residues. Melatonin has the potential to act as a viable alternative to unstable implant coatings. Melatonin, with its capacity to induce bone cell proliferation and differentiation, could facilitate the process of healing of bone tissue in dental implant surgery, reducing the period of osteointegration and settling of the implant, and therefore, the quality of life of the patient may be improved.