In clinical practice, dentists face alveolar bone loss that needs to be managed by bone grafts. The basic bone grafting materials are autograft, allograft, xenograft, and alloplasts. Autografts are gold standard because it has osteoconduction osteoinduction osteogenic. However, they possess risk for the morbidity of the donor site and limited availability. Allograft have possibility of disease transmission and immunologic reactions. These problems potentiated the use of alloplasts. For bone regeneration, hydroxyapatite is the reference material because of its biocompatibility, bioactivity, osteoconductivity, and osteoinductive property. Natural hydroxyapatite can be synthesized from fishbone, coral, bovine bone, eggshell, and seashells. Hydroxyapatite bone substitute has ideal properties for socket preservation, sinus augmentation, periodontal regeneration and in restorative and preventive dentistry. When used as implant coatings, they support osseointegration and osteogenesis. Hydroxyapatite known for its bone regenerative capacity. Nano-hydroxyapatite, with smaller size and wider surface area, permits more proteins and cells to attach to the surface speed up regeneration. Hydroxyapatite are used as inorganic building blocks for tissue engineering or as nano-fillers with polymers. Furthermore, ion doping and surface modifications have been reported to prepare functionalized hydroxyapatite. This chapter illustrates the role of hydroxyapatite in regenerative dentistry, and advances and advantages of using it as a component of other dental materials, whether experimental or commercially available.