Hydroxyapatite-coated implant: Clinical prognosis assessment via a retrospective follow-up study for the average of 3 years

PURPOSE: This research evaluated clinical outcomes of two types of hydroxyapatite (HA)-coated implants: OT (Osstem TS III-HA, Osstem implant Co., Busan, Korea) and ZM (Zimmer TSV-HA, Zimmer dental, Carlsbad, USA). MATERIALS AND METHODS: The research was conducted on 303 implants (89 of OT, 214 of ZM), which were placed from January 16, 2010 to December 20, 2012. The prognosis was evaluated in terms of success rates, survival rates, annual marginal bone loss, and implant stability quotients (ISQ). The samples were classified into immediate, early, conventional, and delayed groups according to the loading time. RESULTS: Overall, there were no significant differences between OT and ZM in success rates, survival rates, and annual marginal bone loss, except for the result of secondary stability. OT showed 77.83 ± 8.23 ISQ, which was marginally higher than 76.09 ± 6.90 ISQ of ZM (P 82.48 ± 3.69 ISQ) (P .05). CONCLUSION: OT (97.75%) and ZM (98.50%) showed relatively good outcomes in terms of survival rates. In general, OT and ZM did not show statistically significant differences in most indices (P>.05), although OT performed marginally better than ZM in the immediate loading and 1-stage surgery (P < .05).

The Effect of Hydroxyapatite Coating on Long-term Results of Total Hip Arthroplasty with Hydroxyapatite-coated Anatomic Femoral Stem / 대한고관절학회지

PURPOSE: To evaluate the clinical and radiological results, as well as the survival rate, associated with total hip arthroplasty using a hydroxyapatite (HA)-coated anatomical femoral stem at a follow-up of > or =12 years. MATERIALS AND METHODS: From April 1992 to May 1997, 86 patients (102 hips) underwent total hip arthroplasty with a HA-coated ABG I (Anatomical Benoist Giraud; Howmedica) hip prosthesis. The average age at the time of surgery was 53.4 years and the mean duration of follow-up was 17.1 years (range, 12.1-21.0 years). The Harris hip score (HHS) and radiographic assessments of thigh pain were used to evaluate the clinical results. We observed osteointegration, cortical hypertrophy, reactive line, calcar resorption and osteolysis around the femoral stems. The survival rate of the femoral stems was evaluated by using the span of time to a revision operation for any reasons was defined as the end point. RESULTS: The mean HHS was 50.5 preoperatively and 84.2 at the time of last follow-up. Osteolysis only around the HA-coated proximal portion of the femoral stem was observed in 72 hips, cortical hypertrophy all around the distal portion of the femoral stem was observed in 38 hips, and calcar resorption was observed in 44 hips. A reactive line was observed in 13 hips, but was unrelated to component loosening. Stem revision operations were performed in 24 (23%) hips due to osteolysis (14 hips), fracture (5 hips) and infection (5 hips). The femoral stem survival rate was 75% over the mean duration of follow-up. CONCLUSION: Total hip arthroplasty using a HA-coated anatomical femoral stem showed necessitated a high rate of revision operations due to osteolysis around the femoral stem in this long term follow-up study.

Surface Characteristics and Biocompatibility of Titanium Coated with Dentin-derived Hydroxyapatite

The aim of this study was to evaluate surface characteristics and biological properties of the dentin-derived hydroxyapatite (HA) coating on titanium substrate. Dentin-derived HA was obtained from extracted human teeth using a calcination method at 850degrees C. The commercially pure titanium (cp-Ti, ASTM Grade II) was used as a metallic substrate and a radio frequency magnetron sputtering method was employed as a coating method. Scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) were utilized to investigate the coating aspects and composition. Atomic forced microscopy (AFM) and a surface profiler were used to assess the surface morphology and roughness. Corrosion tests were performed in phosphate-buffered saline at a 36.5 +/- 1degrees C in order to determine the corrosion behavior of the uncoated and coated specimens. The biocompatibility of dentin-derived HA coated specimens with fetal rat calvarial cells and human gingival fibroblasts was assessed by SEM and cell proliferation analysis. The results showed that the dentin-derived HA coatings appeared to cover thinly and homogeneously the surfaces without changing of the titanium substrate. The EDX analysis of this the coating surface indicated the presence of Ca and P elements. The mean surface roughness of cp-Ti and dentin-derived coating specimens was 0.27 microm and, 1.7 microm, respectively. Corrosion tests indicated a stable passive film of the dentin-derived HA coating specimens. SEM observations of fetal rat calvarial cells and human fibroblast cells on coated surfaces showed that the cells proliferated and developed a network of dense interconnections. The cells on all specimens proliferated actively within the culture period, showing good cell viability. At day 1 and 3, dentin-derived coating specimens showed 89% and 93% cell viability, respectively, when normalized to cp-Ti specimens. These results suggest that dentin-derived HA coating using the RF magnetron sputtering method has good surface characteristics and biocompatibility.

Status of surface treatment in endosseous implant: A literary overview.

The attachment of cells to titanium surfaces is an important phenomenon in the area of clinical implant dentistry. A major consideration in designing implants has been to produce surfaces that promote desirable responses in the cells and tissues. To achieve these requirements, the titanium implant surface can be modified in various ways. This review mainly focuses on the surface topography of dental implants currently in use, emphasizing the association of reported variables with biological outcome.

A study on the biological characteristics of modified titanium surface / 대한치주과학회지

PURPOSE: The purpose of this research is to study about initial adhesion, proliferation and activation of osteoblast to titanium surface treated with machined, hydroxyapatite coating, resorbable blast material blasting and anodizing method. MATERIAL AND METHODS: After treating the titanium surface of each block with machined, impurities were removed and sterilized. The number of cells attached from cultured osteoblast of respective experimental groups were measured at 1, 4, 7, and 14day and alkaline phosphatase, calcium, and inorganic phosphate concentration of cultured solution was measured. RESULT: Anodizing group showed the highest rate of cell attachment and proliferation activity. RBM treated group showed the highest increasing on their alkaline phosphatase activity, on the calcium apposition, on inorganic phosphate apposition of 1 and 4 days in cultured osteoblast to compare with other groups. CONCLUSION: On the basis of these findings, we conclude that surface modification of titanium was profoundly effected on the attachment, proliferation and activation of osteoblast in initial stage osseointegration.

Removal Torque and Histometric Evaluations of Implants with Various Area of Hydroxyapatite Coating Placed in the Rabbit Tibia / 대한치주과학회지

BACKGROUND: This study presents a biomechanical and histometric comparison of bone response to implants with various area of hydroxyapatite(HA) coating. METHODS: The implants were placed in the tibia of 10 rabbits weighing 2.5-3.5kg. The control group had a machined surface, the experimental group 1 had 50micrometer thick HA coated in a band form, and the experimental group 2 had 50micrometer thick HA coated on the entire surface. 8 weeks after implantation, the animals were sacrificed. Removal torque was measured and histologic preparation was also performed for histologic and histometric analysis. Bone to implant contact as well as percentage of bone area inside threads were measured. ANOVA post hoc, and t-test were used for statistical analysis with p-value p<0.05. RESULTS: 1. The removal torques were 9.36 +/- 5.64 Ncm, 48.40 +/- 16.66 Ncm, and 82.37 +/- 22.56 Ncm for the control, exp. 1, and exp. 2 group respectively. Statistically significant difference were found among all the groups(p<0.05). 2. Bone to implant contact in the cortical bone were 38.94 +/- 10.9 %, 66.90 +/- 14.1 %, 73.00 +/- 19.4 %, in the marrow bone, 8.30 +/- 5.4 %, 14.59 +/- 5.9 %, 18.54 +/- 11.8 %, and in total, 22.40 +/- 10.1 %, 31.19 +/- 7.5 %, 41.41 +/- 12.2 % for the control, exp.1, and exp. 2 group respectively . In the cortical bone, exp. 1, and exp. 2 group showed statistically significantly higher contact compared to control group. Total contact and in the marrow bone, only exp. 2 group showed statistically significantly higher contact compared to control group(p<0.05). In all the groups significantly higher contact were observed in the cortical bone compared to the marrow bone(p<0.05). 3. Percentage of bone area inside threads in the cortical bone were 55.68 +/- 7.25 %, 55.19 +/- 13.19 %, 57.04 +/- 13.33 %, in the marrow bone, 12.34 +/- 14.61 %, 17.56 +/- 20.04 %, 20.26 +/- 12.83 %, and in total, 30.30 +/- 12.46 %, 31.57 +/- 15.15 %, 34.25 +/- 12.56 % for the control, exp.1, and exp. 2 group respectively. There was no statistical difference among the groups. In all the groups significantly higher bone area were observed in the cortical bone compared to the marrow bone(p<0.05)