The use of hydroxyapatite bone substitute grafting for alveolar ridge preservation, sinus augmentation, and periodontal bone defect: A systematic review

Objectives: We determined and structurally analyzed the reported effect of hydroxyapatite (HA) bone substitute on alveolar bone regeneration. To the best of our knowledge, no systematic reviews have previously reported the bone regenerative effect of the HA bone substitute. Materials and methods: A literature search was performed for articles published up to August 2015 using MEDLINE with the search terms "hydroxyapatite," "bone regeneration," and "alveolar bone"as well as their known synonyms. The inclusion criteria were set up for human trials with at least five patients. The literature search, eligible article selection, and data extraction were independently performed by two readers, and their agreement was reported by k value. Results: Of the 504 studies found using the MEDLINE literature search, 241 were included for further steps (inter-reader agreement, k = 0.968). Abstract screening yielded 74 studies (k = 0.910), with 42 completely fulfilling the inclusion criteria (k = 0.864). In a final step, 42 studies were further analyzed, with 17 and 25 studies with and without statistical analysis, respectively. The 17 studies reporting similar outcome measures were compared using the calculated 95% confidence intervals. The effect of HA on ridge preservation could not be evaluated. Conclusions: The use of the HA bone substitute interfered with the normal healing process, with significant differences found for sinus augmentation but not for periodontal bone defects. Thus, a bone substitute with optimal bone regenerative properties for alveolar ridge or socket preservation, sinus augmentation, and periodontal bony defect should be developed.