Ong Joo L, Chan Daniel C N
Medical College of Georgia, Department of Oral Rehabilitation, Division of Operative Dentistry, Augusta, Georgia 30912-1260.
Crit Rev Biomed Eng. 2017;45(1-6):411-451. doi: 10.1615/CritRevBiomedEng.v45.i1-6.160.
At present, no standard manufacturing guideline exists for depositing hydroxyapatite (HA) on implant surfaces. Although animal and in vitro studies have reported on the benefits of using HA-coated implants as well as the risks of dissolution, these short-term studies did not demonstrate that the dissolution of the HA coating leads to a loss of implants. In addition, many in vivo and clinical studies did not include the chemical and structural characterization of the coatings, and thus comparisons between studies are difficult. In the clinics, the recommendation is that HA-coated screw implants be used for the anterior maxilla and posterior mandible where the bone depth exceeds 10 mm and when the cortical layer is thinner and spongiosia is less dense. In the posterior maxilla or when the cortical layer is very thin with low density, the use of HA-coated cylindrical implants is recommended. However, there are concerns for using HA-coated implants. The clinician needs to take into consideration the enhanced bacterial susceptibility of HA coatings compared with titanium implants. In addition, the clinician needs to consider the possible failure of HA coatings as a result of coating-substrate interfacial fracture. Finally, besides the surgical skills, it is also important that the clinical investigators be well versed with the materials characterization needed for HA-coated implants, the problems associated with the current HA coatings, and the indications for use. In addition, the correlation between well characterized coatings and their effect on bone formation rate and long-term implant success, coating-implant interfacial strength, and alternative superior coating process need to be investigated further.
目前，在种植体表面沉积羟基磷灰石（HA）尚无标准的制造指南。尽管动物研究和体外研究报告了使用HA涂层种植体的益处以及溶解风险，但这些短期研究并未证明HA涂层的溶解会导致种植体丢失。此外，许多体内和临床研究并未包括涂层的化学和结构表征，因此各研究之间难以进行比较。在临床上，建议在骨深度超过10mm、皮质层较薄且松质骨密度较低的上颌前部和下颌后部使用HA涂层螺钉种植体。在上颌后部或皮质层非常薄且密度低时，建议使用HA涂层圆柱形种植体。然而，使用HA涂层种植体也存在一些问题。临床医生需要考虑到与钛种植体相比，HA涂层对细菌的易感性增强。此外，临床医生还需要考虑由于涂层与基体界面断裂导致HA涂层可能失效的情况。最后，除了手术技巧外，临床研究人员还必须熟悉HA涂层种植体所需的材料表征、当前HA涂层相关的问题以及使用指征。此外，还需要进一步研究表征良好的涂层与其对骨形成速率和种植体长期成功的影响、涂层与种植体的界面强度以及替代的优质涂层工艺之间的相关性。
