Title Hydroxyapatite (HA) Coating on Titanium Implants Increases Osseointegration in the Osteoporotic Animal Model
Clinical Question In an osteoporotic patient, will adding a hydroxyapatite coating to the surface of titanium dental implants aid in the osseointegration process of the dental implant?
Clinical Bottom Line In animals with osteoporosis, HA-coated titanium dental implants were more effective than non-coated implants in promoting osseointegration of the implant to host bone.
Best Evidence  
PubMed ID Author / Year Patient Group Study type
(level of evidence)
22519708Alghamdi/201214 Animal StudiesMeta-Analysis
Key resultsThe Meta-Analysis revealed that in animals with osteoporosis, CaP-coated implants were significantly more effective (p<0.05) at osseointegration than the control (noncoated implants). The difference in the Bone-to-Implant Contact (BIC) in the CaP coated implants versus non-coated implants was 19.2% and the difference of mechanical push-out testing was 105.4 N. However, the difference between the groups in torque-out testing was not statistically significant (p>0.05). More interestingly, a “negative impact of osteoporosis on bone-to-implant healing” could not be confirmed. In other words, there was no difference in the effectiveness of non-coated implants whether the animal was osteoporotic or not. However, it is noted that this may be due to the quality of the studies. Finally, the authors found that, other than in the push-out tests, CaP-coated implants in osteoporotic animals were not more effective than using non-coated implants in healthy animals. It seems that better controlled studies with more animals are needed, but also that, based on the results that CaP-coated implants in osteoporotic animals did not perform much better than uncoated-implants in healthy animals, the statistical difference in improvement in BIC and Push-out test results for CaP-coated implants used in osteoporotic animals may not be clinically significant.
11791904Rocca/200212 Mongrel sheep (2 groups – 6 Ovariectomized, 6 control), each with 12 implanted screws placed bilaterally (3 on each femoral diaphysis and tibial diaphysis)Randomized Controlled Trial
Key resultsThe study evaluated the effect of using hydroxyapatite (HA)-coated implants on extraction torque and affinity index (AI). Use of HA-coated implants resulted in significantly higher extraction torque (Nm) as compared to uncoated implants in the tibiae (F = 3.8, p<0.05) in both ovariectomized and control sheep at 12 weeks post-implantation. Similarly, histomorphometric analysis of the bone-implant contact showed a significantly higher AI in the coated implant as compared to the uncoated implants (femurs: 29.27 AI, tibiae: 10.7 AI, p<0.0005). Furthermore, these values were significantly higher for control sheep when compared with ovariectomized sheep. Therefore, ovariectomized sheep healed more poorly than healthy sheep but the use of HA-coated implants improved osseointegration for both groups. In short, the use of HA-coated implants is suggested for both healthy and osteoporotic patients.
17474132Borsari/200715 female mongrel sheep (3 groups – 5 Young, 5 Aged, 5 Ovariectomized), each with 2 implants in each diaphysis and 1 implant in each epiphysisOther
Key resultsThe study revealed that the use of HA-coated implants resulted in a significant increase in AI (49.9% higher) as compared to noncoated implants but only in trabecular bone and not in cortical bone at 3 months post implantation (F=86.05, p<0.0005). More interestingly, there were no differences in AI between young, aged and OVX animals. HA-coated implants were effective for all animal groups. Thus, it is suggested that HA-coated implants be used in all patients and not just osteoporotic patients.
Evidence Search ((("Bone Regeneration"[Mesh]) AND "Calcium Phosphates"[Mesh]) AND "Osteoporosis"[Mesh]) AND "Prostheses and Implants"[Mesh]
Comments on
The Evidence
The Alghamdi article was a meta analysis with a comprehensive, detailed, and relevant search. Individual studies were assessed for validity. In total, 14 trials were selected and a meta-analysis was done on the data collected. Of the trials that were selected and analyzed, different types of CaP coatings were used. However, the analysis did not consider the effects of the different types of CaP or the different surface morphologies used in the different studies. Thus, some of the conclusions derived in this meta analysis may be flawed. The Rocca article used a RCT design. The groups were similar at the start and were treated equally other than one group being ovariectomized. There was a 100% completion rate, and follow up was adequate at 12 weeks. In the Borsari article, the groups were separated by age at the start and were treated equally other than one age group being ovariectomized. There was a 100% completion rate and follow-up was adequate at 3 months. There did not seem to be any competing interests exhibited in any of the 3 articles.
Applicability The use of hydroxyapatite-coated dental implants shows promise as an option for patients with osteoporosis, as it shows significant positive effects on osseointegration, would be easy to use by a dental professional, and may expand the population to which implants could be used on. Thus far, studies and reviews are limited to animal studies and clinical trials are needed to better assess the clinical performance of HA-coated implants in osteoporotic patients.
Specialty (General Dentistry) (Oral Surgery) (Periodontics) (Prosthodontics) (Restorative Dentistry) (Interprofessional CATs)
Keywords Dental Implants Hydroxyapatite Osseointegration Osteoporosis
ID# 2656
Date of submission 03/04/2014
E-mail jonesjp@livemail.uthscsa.edu
Author Jason Jones
Co-author(s) e-mail
Faculty mentor Kuymin Whang, PhD
Faculty mentor e-mail whang@uthscsa.edu
Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)
None available
Comments and Evidence-Based Updates on the CAT
None available