1
|
Dorozhkin SV. There Are over 60 Ways to Produce Biocompatible Calcium Orthophosphate (CaPO4) Deposits on Various Substrates. JOURNAL OF COMPOSITES SCIENCE 2023; 7:273. [DOI: 10.3390/jcs7070273] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
A The present overview describes various production techniques for biocompatible calcium orthophosphate (abbreviated as CaPO4) deposits (coatings, films and layers) on the surfaces of various types of substrates to impart the biocompatible properties for artificial bone grafts. Since, after being implanted, the grafts always interact with the surrounding biological tissues at the interfaces, their surface properties are considered critical to clinical success. Due to the limited number of materials that can be tolerated in vivo, a new specialty of surface engineering has been developed to desirably modify any unacceptable material surface characteristics while maintaining the useful bulk performance. In 1975, the development of this approach led to the emergence of a special class of artificial bone grafts, in which various mechanically stable (and thus suitable for load-bearing applications) implantable biomaterials and artificial devices were coated with CaPO4. Since then, more than 7500 papers have been published on this subject and more than 500 new publications are added annually. In this review, a comprehensive analysis of the available literature has been performed with the main goal of finding as many deposition techniques as possible and more than 60 methods (double that if all known modifications are counted) for producing CaPO4 deposits on various substrates have been systematically described. Thus, besides the introduction, general knowledge and terminology, this review consists of two unequal parts. The first (bigger) part is a comprehensive summary of the known CaPO4 deposition techniques both currently used and discontinued/underdeveloped ones with brief descriptions of their major physical and chemical principles coupled with the key process parameters (when possible) to inform readers of their existence and remind them of the unused ones. The second (smaller) part includes fleeting essays on the most important properties and current biomedical applications of the CaPO4 deposits with an indication of possible future developments.
Collapse
Affiliation(s)
- Sergey V. Dorozhkin
- Faculty of Physics, M.V. Lomonosov Moscow State University, Leninskie Gory 1-2, Moscow 119991, Russia
| |
Collapse
|
2
|
Abstract
Microstructure and mechanical properties of Ti-6Al-4V/equine bone (EB) composites fabricated by ball milling and spark plasma sintering (SPS) have been investigated. Ti-6Al-4V/EB composites were successfully fabricated by a planetary ball-milling of spherical Ti6Al4V powder and natural EB powder and SPS at 1000 °C within 15 min under 50 MPa. EB was uniformly dispersed in the Ti6Al4V matrix owing to ball-milling, and beta phase transformation temperature of 1000 °C provided phase stability. The composites containing 0.5 wt.% EB exhibit Vickers hardness and elastic modulus of 540.6 HV and 130.5 GPa, respectively. The microstructures and mechanical properties of the composites were observed using scanning electron micrograph and nanoindentation.
Collapse
|
3
|
Jiang N, Guo Z, Sun D, Ay B, Li Y, Yang Y, Tan P, Zhang L, Zhu S. Exploring the mechanism behind improved osteointegration of phosphorylated titanium implants with hierarchically structured topography. Colloids Surf B Biointerfaces 2019; 184:110520. [PMID: 31590052 DOI: 10.1016/j.colsurfb.2019.110520] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/09/2019] [Accepted: 09/21/2019] [Indexed: 02/05/2023]
Abstract
Titanium (Ti) and its alloys have been frequently used in dental and orthopedic implants, but the undesired oxide layer easily formed on the surface tends to be the cause of implant failure for Ti-based implants. To address this problem, we herein prepared a phosphorylated Ti coating (TiP-Ti) with a micro/nano hierarchically structured topography on commercially pure Ti implants by a hydrothermal method to improve its osteointegration capacity. The surface morphology, chemical composition, and biological activity were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), contact-angle measurement, and protein adsorption assay. Osteointegration of TiP-Ti implants in rat tibia was investigated by biomechanical testing, micro-CT and histological analyses. We further explored the proposed mechanism which improves osteointegration of TiP-Ti implants by proliferation, adhesion, and differentiation assays of rat bone marrow mesenchymal stem cells (BMSCs). Our results demonstrated that the improved osteointegration mainly benefited from the better spread and adhesion of BMSCs on the micro/nano hierarchically structured TiP-Ti surfaces compared to hydroxyapatite coated Ti (HA-Ti), the positive control, and untreated Ti (untreated-Ti), the negative control. In conclusion, TiP-Ti surface is a promising candidate implant surface design to accelerate the osteointegration of Ti-based implants in biomedical applications.
Collapse
Affiliation(s)
- Nan Jiang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Disease & West China Hospital of Stomatology, Analytical and Testing Center, Sichuan University, Chengdu 610065, China
| | - Zhijun Guo
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Disease & West China Hospital of Stomatology, Analytical and Testing Center, Sichuan University, Chengdu 610065, China
| | - Dan Sun
- School of Mechanical and Aerospace Engineering, Queens University Belfast, Belfast BT7 1NN, UK
| | - Birol Ay
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, M5S 3E3, Canada
| | - Yubao Li
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Disease & West China Hospital of Stomatology, Analytical and Testing Center, Sichuan University, Chengdu 610065, China
| | - Yutao Yang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Disease & West China Hospital of Stomatology, Analytical and Testing Center, Sichuan University, Chengdu 610065, China
| | - Peijie Tan
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Disease & West China Hospital of Stomatology, Analytical and Testing Center, Sichuan University, Chengdu 610065, China
| | - Li Zhang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Disease & West China Hospital of Stomatology, Analytical and Testing Center, Sichuan University, Chengdu 610065, China.
| | - Songsong Zhu
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Disease & West China Hospital of Stomatology, Analytical and Testing Center, Sichuan University, Chengdu 610065, China.
| |
Collapse
|
4
|
Kuroda K, Okido M. Osteoconductivity Control Based on the Chemical Properties of the Implant Surface. ACTA ACUST UNITED AC 2018. [DOI: 10.4236/jbnb.2018.91003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
5
|
Calcium orthophosphate deposits: Preparation, properties and biomedical applications. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2015; 55:272-326. [PMID: 26117762 DOI: 10.1016/j.msec.2015.05.033] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 03/21/2015] [Accepted: 05/08/2015] [Indexed: 01/12/2023]
Abstract
Since various interactions among cells, surrounding tissues and implanted biomaterials always occur at their interfaces, the surface properties of potential implants appear to be of paramount importance for the clinical success. In view of the fact that a limited amount of materials appear to be tolerated by living organisms, a special discipline called surface engineering was developed to initiate the desirable changes to the exterior properties of various materials but still maintaining their useful bulk performances. In 1975, this approach resulted in the introduction of a special class of artificial bone grafts, composed of various mechanically stable (consequently, suitable for load bearing applications) implantable biomaterials and/or bio-devices covered by calcium orthophosphates (CaPO4) to both improve biocompatibility and provide an adequate bonding to the adjacent bones. Over 5000 publications on this topic were published since then. Therefore, a thorough analysis of the available literature has been performed and about 50 (this number is doubled, if all possible modifications are counted) deposition techniques of CaPO4 have been revealed, systematized and described. These CaPO4 deposits (coatings, films and layers) used to improve the surface properties of various types of artificial implants are the topic of this review.
Collapse
|
6
|
Bone Ingrowth and Initial Stability of Titanium and Porous Tantalum Dental Implants. IMPLANT DENT 2013; 22:399-405. [DOI: 10.1097/id.0b013e31829b17b5] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
7
|
Al-Sanabani JS, Madfa AA, Al-Sanabani FA. Application of calcium phosphate materials in dentistry. Int J Biomater 2013; 2013:876132. [PMID: 23878541 PMCID: PMC3710628 DOI: 10.1155/2013/876132] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2013] [Revised: 05/03/2013] [Accepted: 05/29/2013] [Indexed: 11/18/2022] Open
Abstract
Calcium phosphate materials are similar to bone in composition and in having bioactive and osteoconductive properties. Calcium phosphate materials in different forms, as cements, composites, and coatings, are used in many medical and dental applications. This paper reviews the applications of these materials in dentistry. It presents a brief history, dental applications, and methods for improving their mechanical properties. Notable research is highlighted regarding (1) application of calcium phosphate into various fields in dentistry; (2) improving mechanical properties of calcium phosphate; (3) biomimetic process and functionally graded materials. This paper deals with most common types of the calcium phosphate materials such as hydroxyapatite and tricalcium phosphate which are currently used in dental and medical fields.
Collapse
Affiliation(s)
- Jabr S. Al-Sanabani
- Department of Oral Medicine and Oral Diagnosis, Faculty of Dentistry, University of Thamar, Dhamar 87407, Yemen
| | - Ahmed A. Madfa
- Department of Conservative Dentistry, Faculty of Dentistry, University of Thamar, Dhamar 87407, Yemen
| | - Fadhel A. Al-Sanabani
- Department of Conservative Dentistry, Faculty of Dentistry, University of Thamar, Dhamar 87407, Yemen
| |
Collapse
|
8
|
Urdaneta RA, Leary J, Panetta KM, Chuang SK. The effect of opposing structures, natural teeth vs. implants on crestal bone levels surrounding single-tooth implants. Clin Oral Implants Res 2012; 25:e179-88. [DOI: 10.1111/clr.12087] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/30/2012] [Indexed: 11/30/2022]
Affiliation(s)
| | | | | | - Sung-Kiang Chuang
- Department of Oral and Maxillofacial Surgery; Massachusetts General Hospital and Harvard School of Dental Medicine; Boston MA USA
| |
Collapse
|
9
|
Dorozhkin SV. Calcium orthophosphate coatings, films and layers. Prog Biomater 2012; 1:1. [PMID: 29470670 PMCID: PMC5120666 DOI: 10.1186/2194-0517-1-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 06/14/2012] [Indexed: 11/16/2022] Open
Abstract
In surgical disciplines, where bones have to be repaired, augmented or improved, bone substitutes are essential. Therefore, an interest has dramatically increased in application of synthetic bone grafts. As various interactions among cells, surrounding tissues and implanted biomaterials always occur at the interfaces, the surface properties of the implants are of the paramount importance in determining both the biological response to implants and the material response to the physiological conditions. Hence, a surface engineering is aimed to modify both the biomaterials, themselves, and biological responses through introducing desirable changes to the surface properties of the implants but still maintaining their bulk mechanical properties. To fulfill these requirements, a special class of artificial bone grafts has been introduced in 1976. It is composed of various mechanically stable (therefore, suitable for load bearing applications) biomaterials and/or bio-devices with calcium orthophosphate coatings, films and layers on their surfaces to both improve interactions with the surrounding tissues and provide an adequate bonding to bones. Many production techniques of calcium orthophosphate coatings, films and layers have been already invented and new promising techniques are continuously investigated. These specialized coatings, films and layers used to improve the surface properties of various types of artificial implants are the topic of this review.
Collapse
|
10
|
Vignoletti F, Abrahamsson I. Quality of reporting of experimental research in implant dentistry. Critical aspects in design, outcome assessment and model validation. J Clin Periodontol 2012; 39 Suppl 12:6-27. [DOI: 10.1111/j.1600-051x.2011.01830.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Fabio Vignoletti
- Department of Periodontology; Faculty of Odontology; Complutense University of Madrid; Madrid; Spain
| | - Ingemar Abrahamsson
- Department of Periodontology; Institute of Odontology; The Sahlgrenska Academy; University of Gothenburg; Gothenburg; Sweden
| |
Collapse
|
11
|
Hydroxyapatite coating of titanium implants using hydroprocessing and evaluation of their osteoconductivity. Bioinorg Chem Appl 2012; 2012:730693. [PMID: 22400015 PMCID: PMC3287042 DOI: 10.1155/2012/730693] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 10/21/2011] [Indexed: 11/17/2022] Open
Abstract
Many techniques for the surface modification of titanium and its alloys have been proposed from the viewpoint of improving bioactivity. This paper contains an overview of surface treatment methods, including coating with hydroxyapatite (HAp), an osteoconductive compound. There are two types of coating methods: pyroprocessing and hydroprocessing. In this paper, hydroprocessing for coating on the titanium substrate with HAp, carbonate apatite (CO3–Ap), a CO3–Ap/CaCO3 composite, HAp/collagen, and a HAp/gelatin composite is outlined. Moreover, evaluation by implantation of surface-modified samples in rat tibiae is described.
Collapse
|
12
|
Thompson JY, Stoner BR, Piascik JR. Ceramics for restorative dentistry: Critical aspects for fracture and fatigue resistance. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2007. [DOI: 10.1016/j.msec.2006.05.034] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
13
|
Stewart M, Welter JF, Goldberg VM. Effect of hydroxyapatite/tricalcium-phosphate coating on osseointegration of plasma-sprayed titanium alloy implants. J Biomed Mater Res A 2004; 69:1-10. [PMID: 14999745 DOI: 10.1002/jbm.a.20071] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study determined the effects of a plasma-sprayed hydroxyapatite/tricalcium phosphate (HA/TCP) coating on osseointegration of plasma-sprayed titanium alloy implants in a lapine, distal femoral intramedullary model. The effects of the HA/TCP coating were assessed at 1, 3, and 6 months after implant placement. The HA/TCP coating significantly increased new bone apposition onto the implant surfaces at all time points. The ceramic coating also stimulated intramedullary bone formation at the middle and distal levels of the implants. Fluorescent bone labeling indicated that new bone formation occurred primarily during the first 3 months after implantation, with comparatively little activity detected in the latter stages of the study. There was no associated increase in pullout strength at either 3 or 6 months; however, post-pullout evaluation of the implants indicated that the HA/TCP coating itself was not the primary site of construct failure. Rather, failure was most commonly observed through the periprosthetic osseous struts that bridged the medullary cavity. The demonstrated osteoconductive activity of HA/TCP coating on plasma-sprayed titanium alloy implant surfaces may have considerable clinical relevance to early host-implant interactions, by accelerating the establishment of a stable prosthesis-bone interface.
Collapse
Affiliation(s)
- Matthew Stewart
- Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, 1008W Hazelwood Drive, Urbana, Illinois 61802, USA.
| | | | | |
Collapse
|
14
|
Barrère F, van der Valk CM, Dalmeijer RAJ, Meijer G, van Blitterswijk CA, de Groot K, Layrolle P. Osteogenecity of octacalcium phosphate coatings applied on porous metal implants. J Biomed Mater Res A 2003; 66:779-88. [PMID: 12926029 DOI: 10.1002/jbm.a.10454] [Citation(s) in RCA: 190] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The biomimetic route allows the homogeneous deposition of calcium phosphate (Ca-P) coatings on porous implants by immersion in simulated physiologic solution. In addition, various Ca-P phases, such as octacalcium phosphate (OCP) or bone-like carbonated apatite (BCA), which are stable only at low temperatures, can be deposited. In this pilot study, experiments were designed with a twofold-purpose: (1) to investigate the osteoinduction of OCP-coated and noncoated porous tantalum cylinders and of dense titanium alloy cylinders (5 mm in diameter and 10 mm in length) in the back muscle of goats at 12 and 24 weeks (n = 4); and (2) to compare the osteogenic potentials of BCA-coated, OCP-coated, and bare porous tantalum cylinders in a gap of 1 mm created in the femoral condyle of a goat at 12 weeks (n = 2). In the goat muscle, after 12 weeks the OCP-coated porous cylinder had induced ectopic bone as well as bone within the cavity of the OCP-coated dense titanium cylinder. In the femoral condyle, bone did not fill the gap in any of the porous implants. In contrast with the two other groups, OCP-coated porous cylinders exhibited bone formation in the center of the implant. The nature of the Ca-P coating, via its microstructure, its dissolution rate, and its specific interactions with body fluids, may influence the osteogenecity of the Ca-P biomaterial.
Collapse
Affiliation(s)
- Florence Barrère
- IsoTis NV, Prof Bronkhorstlaan 10, PO Box 98, 3720 AB Bilthoven, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
15
|
Yacoub N, Ismail YH, Mao JJ. Transmission of bone strain in the craniofacial bones of edentulous human skulls upon dental implant loading. J Prosthet Dent 2002; 88:192-9. [PMID: 12397247 DOI: 10.1067/mpr.2002.127401] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
STATEMENT OF PROBLEM Little is known about how craniofacial bones that are distant from dental implants are loaded. Whether bone experiences different strain when implants of different diameters are loaded is unknown. PURPOSE This study was designed to (1) characterize bone strain both adjacent to and distant from dental implants and (2) compare bone strain in response to the same loads on small-diameter and large-diameter implants. MATERIAL AND METHODS On 4 edentulous, dry adult human skulls, the buccopalatal midpoint of the edentulous occlusal surface was marked unilaterally in the maxillary first molar area with a round bur. A hole for implant placement was prepared, and 2 self-tapping titanium implants (3.75 x 7 mm and 4 x 7 mm) were placed in the same location and at the same orientation, one after the other. A 4-mm-long titanium abutment was connected to the implant. Each implant was loaded 10 degrees lateral to its longitudinal axis, simulating a lateral occlusal force in 3 of the skulls. In skull 2, loading was along the longitudinal axis of the implant and simulated a vertical occlusal force. The magnitude of the ramp forces was 0 to 100 N. Uniaxial strain gages and/or 3-element strain rosettes were implanted in the supramolar cortical bone, the supraincisor cortical bone, the zygomaticomaxillary suture, and the zygomaticotemporal suture. All strain gages/rosettes were excited with 500 mV DC, and the output signals were recorded with a strain conditioner. Tensile strain was expressed as positive values and compressive strain as negative values. Student t tests were used to test for normal distribution of bone strain within each skull; Wilcoxon tests were applied for skewed distribution between small- and large-diameter implants and between 50-N and 100-N loads (P<or=.05). RESULTS Bone strain both adjacent to and distant from the implants was complex: compressive strain in the buccal cortical bone superior to the implants; tensile strain in the ipsilateral supraincisor cortical bone but compressive strain in the contralateral supraincisor cortical bone; and tensile strain anterior to the zygomaticotemporal suture but compressive strain posterior to the suture. With the same applied loads, bone strain was higher for large-diameter implants than for small-diameter implants for all the above cortical locations (P<.01 to.001) except posterior to the zygomaticotemporal suture. CONCLUSION Within the limitations of this study, bone strain resulting from dental implant loading was distributed to cortices not only adjacent to but also distant from dental implants. The large-diameter implant was more facilitative of stress transfer to cortical bone than the small-diameter implant tested.
Collapse
Affiliation(s)
- Nidal Yacoub
- School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | | | | |
Collapse
|
16
|
Yoshinari M, Oda Y, Inoue T, Matsuzaka K, Shimono M. Bone response to calcium phosphate-coated and bisphosphonate-immobilized titanium implants. Biomaterials 2002; 23:2879-85. [PMID: 12069328 DOI: 10.1016/s0142-9612(01)00415-x] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Thin calcium phosphate (Ca-P) coatings have been introduced to overcome the shortcomings of plasma-sprayed Ca-P coatings. In our previous experiments, thin Ca-P coatings also enabled the immobilization of bisphosphonate, which is a drug used to treat osteoporosis. The present study was designed to evaluate the bone response to titanium implants treated with a thin Ca-P coating and bisphosphonate. Forty cylindrical commercially pure titanium implants with a length of 7 mm and a diameter of 3 mm were used as test implant fixtures. Three groups of surface-treated implants were prepared: (1) blasted with titanium powder and etched with a solution of 10% HF + 5% HNO3 (control); (2) modified with 0.5-microm thick Ca-P coatings and rapid heat-treating, and (3) immobilized with bisphosphonate by immersion in pamidronate disodium solution (10(-2) M) for 24 h at 37 degrees C. These surface-treated implants were inserted into edentulous areas in the mandibular molar region of five beagle dogs. After implantation periods of 4 and 12 weeks, the bone implant interface was evaluated histologically and histomorphometrically. All measurements were statistically evaluated using a one-way ANOVA and Fisher PLSD test for multiple comparisons among the means. Four weeks after the implantation, higher percentage of bone contact was found around the thin Ca-P-coated implants compared to that of the control group. The highest percentage of bone contact was found around the bisphosphonate-immobilized implants after 12 weeks of implantation. These data suggest that a thin coating of calcium phosphate followed by bisphosphonate-immobilization is effective in the promotion of osteogenesis on surfaces of dental implants.
Collapse
Affiliation(s)
- M Yoshinari
- Department of Dental Materials Science, Oral Health Science Center, Tokyo Dental College, Chiba, Japan.
| | | | | | | | | |
Collapse
|
17
|
Tomotake Y, Ichikawa T, Kanitani H, Nakao M, Kitaoka N. Dynamics of bone marrow pressure with tapping of titanium and hydroxyapatite implants in rabbits. Clin Oral Implants Res 2002; 13:221-4. [PMID: 11952743 DOI: 10.1034/j.1600-0501.2002.130213.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The purpose of the present study was to evaluate the difference in stress transfer between titanium (Ti) and hydroxyapatite (HA) by the measurement of bone marrow pressure using a catheter pressure transducer. Ti and HA implants were inserted in the tibiae of rabbits. A hole of 1 mm in diameter was drilled in the bone and a fine catheter pressure transducer was placed in the bone marrow through a tube. The top of the abutment was vertically tapped with an impulse hammer, and the acceleration signal from the hammer and pressure signal from the catheter pressure transducer were examined. The time of contact (impulse duration) recorded in the impulse with Ti and HA was 166+/-17 micro sec and 164 +/- 17 micro sec, respectively. Maximum bone marrow pressure (BMP) with Ti and HA was 54.2 +/- 32.6 and 47.5 +/- 10.0 mmHg, respectively. Variation of the BMP with Ti was significantly larger than that with HA (P < 0.05). A negative correlation coefficient between impulse duration and BMP was found. The results of the present study suggest that the stress transfer is different between Ti and HA implants using dynamics of the bone marrow pressure.
Collapse
Affiliation(s)
- Yoritoki Tomotake
- Department of Removable Prosthodontics, The University of Tokushima, School of Dentistry, Japan
| | | | | | | | | |
Collapse
|
18
|
Hayakawa T, Yoshinari M, Kiba H, Yamamoto H, Nemoto K, Jansen JA. Trabecular bone response to surface roughened and calcium phosphate (Ca-P) coated titanium implants. Biomaterials 2002; 23:1025-31. [PMID: 11791905 DOI: 10.1016/s0142-9612(01)00214-9] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The influence of calcium phosphate (Ca-P) coating and surface roughness on the trabecular bone response of titanium implants was investigated. Four types of titanium implants, i.e. blasted with titanium powder, sintered with titanium beads, titanium powder blasted and provided with an additional Ca-P coating, and titanium beads with Ca-P coating, were prepared. The Ca-P coating was deposited by ion beam dynamic mixing method. The Ca-P coating was rapid heat-treated with infrared radiation at 700 degrees C. The implants were inserted into the trabecular bone of the left and right femoral condyles of 16 rabbits. After implantation periods of 2, 3, 4 and 12 weeks, the bone-implant interface was evaluated histologically and histomorphometrically. Histological evaluation revealed new bone formation around different implant materials after already 3 weeks of implantation. After 12 weeks, mature trabecular bone surrounded all implants. At 3 and 4 weeks of implantation, no difference existed in bone contact to the various implant materials. On the other hand, after 12 weeks of implantation the highest percentage of bone contact was found around the Ca-P coated beads implants. Supported by the results, we concluded that the combination of surface geometry and Ca-P coating benefits the implant-bone response during the healing phase.
Collapse
Affiliation(s)
- Tohru Hayakawa
- Department of Dental Materials, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
| | | | | | | | | | | |
Collapse
|
19
|
Kuroda K, Ichino R, Okido M, Takai O. Hydroxyapatite coating on titanium by thermal substrate method in aqueous solution. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2002; 59:390-7. [PMID: 11745577 DOI: 10.1002/jbm.10002] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A new hydrocoating method (the thermal substrate method) is proposed for coating calcium phosphates such as hydroxyapatite (HA), on titanium substrates in an aqueous solution. Several factors (e.g., the type of ion source, the heating time and temperature, and the surface roughness of the substrate) affected the characteristics of the precipitate formed by this method. The solution used included 3 mmol dm(-3) Ca(H(2)PO(4))(2) and 7 mmol dm(-3) CaCl(2), and its pH was adjusted to 6.5. The experimental studies were conducted under the following conditions: temperature 45-160 degrees C, heating time 10-20 min, and surface roughness of substrate #120-#2000 grid ground using energy paper. A high quality of precipitate, whose predominant component was HA, was obtained on titanium substrates by the thermal substrate method in an aqueous solution. No significant difference in the precipitates was found with the type of ion source. The amount of HA precipitate increased with increasing temperature and with increasing heating time. The features of the precipitate were different, depending on the surface roughtness of the substrate: HA regularly nucleated along the grooves of the rough surface (#120 and #400 grid), and in the case of the fine surface (#1200-#2000 grid), a uniform precipitation occurred.
Collapse
Affiliation(s)
- Kensuke Kuroda
- Center for Integrated Research in Science and Engineering, Nagoya University, Japan.
| | | | | | | |
Collapse
|
20
|
Yen SK, Guo MJ, Zan HZ. Characterization of electrolytic ZrO2 coating on Co-Cr-Mo implant alloys of hip prosthesis. Biomaterials 2001; 22:125-33. [PMID: 11101157 DOI: 10.1016/s0142-9612(00)00133-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
An electrolytic Zr(OH)4 gel has been coated on ASTM F-75 Co-Cr-Mo alloy specimens in 0.0625 M ZrO(NO3)2 solution with pH = 2.2 at a current density of 2 mA/cm2. After annealing at 623-973 K for 120 min in air, the ZrO2-coated specimen was evaluated by electrochemical polarization in Hank's solution, wear tests with UHMWPE (Ultra-high molecular-weight polyethylene) under a load stress of 50 MPa, scratch tests, surface morphology observations, and XRD analysis. The ZrO2-coated specimen annealed at 773 K for 120 min revealed a good adhesion of 610 MPa on Co-Cr-Mo substrate, a lower wear loss of UHMWPE and a higher protection potential than the uncoated specimen in Hank's solution. A monoclinic structure with (1 1 1) preferred orientation parallel to the sheet plane was detected at 623 K < or = T < or = 673 K and a tetragonal structure of ZrO2 was detected at T > or = 773 K. Then a monoclinic structure with random orientation and a tetragonal structure were mixed at T > or = 973 K.
Collapse
Affiliation(s)
- S K Yen
- Institute of Materials Engineering, National Chung Hsing University, Taichung, Taiwan.
| | | | | |
Collapse
|
21
|
Abstract
Dense hydroxyapatite (HA) is widely believed to be unsuitable for clinical use as dental implants due to its poor mechanical properties, although it has excellent biocompatibility and is chemically stable and nonresorbable in vivo. However, the case in this article is one in which the patient's dense HA implants are still stable and in good functional condition 16.5 years after he received four pieces of a one-piece dense HA implant in both sides of his lower molar regions. Furthermore, almost no radiolucency is evident along the root portions of the implant sites in the bone. These findings imply that dense HA can be clinically useful and should be reevaluated as a dental implant material.
Collapse
Affiliation(s)
- M Ogiso
- Department of Fixed Prosthodontics, Faculty of Dentistry, Tokyo Medical and Dental University, Japan
| |
Collapse
|
22
|
Gineste L, Gineste M, Ranz X, Ellefterion A, Guilhem A, Rouquet N, Frayssinet P. Degradation of hydroxylapatite, fluorapatite, and fluorhydroxyapatite coatings of dental implants in dogs. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2000; 48:224-34. [PMID: 10398025 DOI: 10.1002/(sici)1097-4636(1999)48:3<224::aid-jbm5>3.0.co;2-a] [Citation(s) in RCA: 148] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Calcium phosphate coatings on dental implants enhance integration of the material. Resorption of the ceramic coatings has raised some concern about the behavior of the bone-implant interfaces after the coating disappearance. Substitution of the OH- ions by fluoride in the hydroxylapatite (HA) lattice makes the calcium phosphate more stable. We investigated the degradation rate of dental implants with 50- and 100-microm coatings of HA, fluorapatite (FA), or fluorhydroxylapatite (FHA). The implants were inserted in dog jaws and retrieved for histological analysis after 3, 6, and 12 months. The thickness of the calcium phosphate coatings was evaluated using an image analysis device. A relative resorption index and its standard deviation were studied. HA and FA coatings (even at 100-microm thickness) were almost totally degraded within the implantation period. In contrast, the FHA coatings did not show significant degradation during the same period. The standard deviation showed that the resorption process for FHA with thicknesses of 50 or 100 microm was the same. Such a difference was not observed between the 50- and 100-microm thick coatings of FA and HA. In conclusion, the FHA coatings showed good integration in the bone tissue and lasted much longer than classic calcium phosphate coatings.
Collapse
Affiliation(s)
- L Gineste
- Periodontology Department, Dental School, Chemin des Maraïchers, Toulouse, France
| | | | | | | | | | | | | |
Collapse
|
23
|
Simmons CA, Valiquette N, Pilliar RM. Osseointegration of sintered porous-surfaced and plasma spray-coated implants: An animal model study of early postimplantation healing response and mechanical stability. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1999; 47:127-38. [PMID: 10449624 DOI: 10.1002/(sici)1097-4636(199911)47:2<127::aid-jbm3>3.0.co;2-c] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The osseointegration and long-term success of bone-interfacing implants are dependent on mechanical stability of the implant relative to host bone during the early healing period. The geometric design of an implant surface may play an important role in affecting early implant stabilization, possibly by influencing tissue healing dynamics. In this study, we compared the early tissue healing response and resulting implant stability for two surface designs by characterizing the histological and mechanical properties of the healing tissue around Ti6Al4V sintered porous-surfaced and Ti plasma-sprayed implants. The implants were inserted transversely in rabbit femoral condyles and evaluated at 0, 4, 8, and 16 days postimplantation. At 4 and 8 days after implantation, the early healing tissue (fibrin and collagenous matrix) was more extensively integrated with the three-dimensional interconnected structure of the sintered porous surface than with the irregular geometry of the plasma-sprayed coating. In addition, histological examination indicated that initial matrix mineralization leading to osseointegration occurred more rapidly with the porous-surfaced implants. The more extensive tissue integration and more rapid matrix mineralization with the porous-surfaced implants were reflected in the mechanical test data, which demonstrated greater attachment strength and interfacial stiffness for the porous-surfaced implants 4 and 8 days postimplantation (p <.05). Sixteen days after implantation, both implant designs were osseointegrated and had comparable attachment characteristics. These data demonstrate that appropriate surface design selection can improve early implant stability and induce an accelerated healing response, thereby improving the potential for implant osseointegration.
Collapse
Affiliation(s)
- C A Simmons
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 170 College Street, Toronto, Ontario M5S 3E3, Canada
| | | | | |
Collapse
|
24
|
Ogiso M, Yamashita Y, Matsumoto T. The process of physical weakening and dissolution of the HA-coated implant in bone and soft tissue. J Dent Res 1998; 77:1426-34. [PMID: 9649171 DOI: 10.1177/00220345980770060701] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Hydroxyapatite (HA)-coated implants were developed to promote osseointegration of titanium implants and to overcome the mechanical drawbacks of solid HA implants. Although many clinical reports on the prognosis of HA-coated implants have reported high success rates, the risks of dissolution and weakening of the coating have been noted. We hypothesized that the chemical and mechanical stability of HA coating are affected by its microstructural characteristics. The present study investigates differences in the microstructures of available HA-coated implants, before and after implantation into the coxal bones of dogs for periods ranging from 3 weeks to 10 months and under the coxal periosteum of dogs for 10 months. The results of transmission electron microscopy and energy-dispersive x-ray analysis revealed that crystallization of super-fine HA crystals occurred in the amorphous phase of the HA coating and progressed over time. This crystallization weakens HA-coated implants by making the amorphous phase brittle, causing stress accumulation within the coating, and causing a decrease in the binding strength between the coating and the substrate. Furthermore, the HA coating dissolved in soft tissue. Dissolution started with the super-fine HA crystals in the crystallized portion that was originally part of the amorphous phase.
Collapse
Affiliation(s)
- M Ogiso
- Department of Fixed Prosthodontics, Faculty of Dentistry, Tokyo Medical and Dental University, Japan
| | | | | |
Collapse
|
25
|
Implant Design and Manufacturing as Predictors of Implant Failure. Oral Maxillofac Surg Clin North Am 1998. [DOI: 10.1016/s1042-3699(20)30330-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
26
|
Jones JD, Saigusa M, Van Sickels JE, Tiner BD, Gardner WA. Clinical evaluation of hydroxyapatite-coated titanium plasma-sprayed and titanium plasma-sprayed cylinder dental implants: a preliminary report. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 1997; 84:137-41. [PMID: 9269013 DOI: 10.1016/s1079-2104(97)90058-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE The purpose of this article was to present the preliminary results of a prospective clinical trial comparing titanium plasma-sprayed versus hydroxyapatite-coated titanium plasma-sprayed cylinder (press fit) implants in different regions of the mouth. STUDY DESIGN Sixty-five subjects met the inclusion requirements. Surgery was done in two phases by four experienced surgeons. Implant placement and abutment connection were separated by 3 to 4 months in the mandible, 6 to 7 months in the maxilla. Patients were assigned to either titanium plasma-sprayed or hydroxyapatite-coated implants on the day of surgery. Implant placement was not stratified for the region of the jaws. Outcome assessment was failure (loss) of an implant before or within 3 months of second phase surgery. RESULTS Three hundred fifty-two implants equally distributed between titanium plasma-sprayed and hydroxyapatite-coated titanium plasma-sprayed implants were placed in four different sites; anterior maxilla, posterior maxilla, anterior mandible, and posterior mandible. There were a total of 15 failures (4.26%). Overall, titanium plasma-sprayed implants showed a higher but not significant failure rate compared with hydroxyapatite-coated implants (p = 0.06). Although not statistically significant, we believe that a smoking history played an important role in the failure of implants. CONCLUSION This study suggests that an hydroxyapatite-coating of an implant allows superior initial integration when compared with a titanium plasma-sprayed surface.
Collapse
Affiliation(s)
- J D Jones
- Department of Prosthodontics, University of Texas, Health Science Center, San Antonio, USA
| | | | | | | | | |
Collapse
|
27
|
Yoshinari M, Watanabe Y, Ohtsuka Y, Dérand T. Solubility control of thin calcium-phosphate coating with rapid heating. J Dent Res 1997; 76:1485-94. [PMID: 9240385 DOI: 10.1177/00220345970760081101] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The thin calcium-phosphate (Ca-P) coatings produced by the ion-beam-mixing method instead of the plasma-spraying method have been found to be amorphous, resulting in films that easily dissolved in simulated body fluid. These coatings crystalized with conventional heat treatment in an electric furnace but tended to crack easily. Therefore, the purpose of this study was to find a suitable heat treatment that controls the solubility of Ca-P coatings without weakening their adhesion to titanium (Ti) substrate. Thin coatings (approximately 1 microm) were coated onto Ti substrates, followed by heat treatment in a conventional furnace and rapid heating by infrared radiation and laser radiation. X-ray diffraction analysis revealed untreated films to be amorphous but to become crystalline after being heated in a furnace at 500 degrees C, heated rapidly with infrared radiation higher than 600 degrees C and with laser radiation at output power of 10W. We evaluated solubility by estimating the film thickness after immersion in simulated body fluid for 5 weeks: Untreated films dissolved within 1 day. Coatings treated with infrared radiation at 600 degrees C dissolved minimally. Cracks were observed in coatings subjected to infrared radiation at 800 degrees C and furnace-heated at 500 degrees C. Coatings treated with laser radiation tended to dissolve easily, with non-uniform surface degradation. X-ray photoelectron spectroscopy analysis at the interface between the coating and the Ti substrate showed that cracks were the result of decreased Ca-implanted layers and too much growth of Ti-P compounds. No difference was recognized in the Ti-oxidation state among specimens. These data indicate that rapid, homogeneous, and comparatively low-temperature heating, such as defocused infrared radiation, controls Ca-P solubility and ensures the adherence of the coatings to the substrate.
Collapse
Affiliation(s)
- M Yoshinari
- Department of Dental Materials Science and Oral Health Science Center, Tokyo Dental College, Mihama-ku, Chiba, Japan
| | | | | | | |
Collapse
|
28
|
Caulier H, van der Waerden JP, Wolke JG, Kalk W, Naert I, Jansen JA. A histological and histomorphometrical evaluation of the application of screw-designed calciumphosphate (Ca-P)-coated implants in the cancellous maxillary bone of the goat. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1997; 35:19-30. [PMID: 9104695 DOI: 10.1002/(sici)1097-4636(199704)35:1<19::aid-jbm3>3.0.co;2-p] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Various studies already have shown that the occurrence of oral implant failure is higher in the maxilla than in the mandible. To learn whether Ca-P coatings can improve the success rate of oral implants in the maxilla, three different plasma-sprayed, Ca-P-coated, self-tapping Brånemark implants were inserted in the trabecular bone of the maxilla. Before the insertion of the implants, the two first upper premolars of 16 goats were bilaterally extracted. Four months later, each animal received four types of implants: three different Ca-P-coated types and one uncoated. After an endosseous period of 6 months, the implants were provided with permucosal abutments. Four months later the animals were killed. At the end of the experiment, it appeared that 10 of the 16 installed noncoated implants had failed while of the 48 Ca-P-coated implants, only 6 had failed. All successful implants were retrieved and prepared for histomorphometrical evaluation of the bone and gingiva response. The Ca-P-coated implants showed a significantly greater percentage of bone in contact with the implant surface compared with the uncoated implants. The length of the epithelium was not significantly different for the coated compared to the uncoated implants, but the connective tissue was significantly thicker for the noncoated implants than for the Ca-P-coated implants. Also, measurements revealed that all coatings showed reduction in thickness. On the basis of these findings, we concluded that the application of Ca-P coatings (1) improves the bone-implant reaction, although all coatings reduced in thickness, and (2) is of benefit during the healing period in less mineralized trabecular bone.
Collapse
Affiliation(s)
- H Caulier
- University of Nijmegen, Department of Oral Function, Dental School, The Netherlands
| | | | | | | | | | | |
Collapse
|
29
|
Affiliation(s)
- D Cochran
- Department of Periodontics, Health Sciences Center, University of Texas, San Antonio, USA
| |
Collapse
|
30
|
Abstract
In this article, the authors describe the application of a new and unique root-form dental implant in a simplified approach to treating the completely edentulous mandible using an overdenture. The technique is supported by the results of a prospective clinical trial involving 52 patients that showed a three- to four-year success rate of 95 percent.
Collapse
Affiliation(s)
- D A Deporter
- Department of Periodontology, University of Toronto, Faculty of Dentistry, Toronto, Ontario, Canada
| | | | | |
Collapse
|
31
|
Nugiel DJ, Wood DJ, Sung KLP. Quantification of Adhesiveness of Osteoblasts to Titanium Surfacesin Vitroby the Micropipette Aspiration Technique. ACTA ACUST UNITED AC 1996; 2:127-40. [DOI: 10.1089/ten.1996.2.127] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Dale J. Nugiel
- Institute of Biomedical Engineering, Department of Bioengineering, University of California, San Diego, La Jolla, California 92093-0412
| | - Douglas J. Wood
- Institute of Biomedical Engineering, Department of Bioengineering, University of California, San Diego, La Jolla, California 92093-0412
| | - K-L. Paul Sung
- Institute of Biomedical Engineering, Departments of Bioengineering and Orthopaedics, University of California, San Diego, La Jolla, California 92093-0412
| |
Collapse
|
32
|
Levy D, Deporter DA, Watson PA, Pilliar RM. Periodontal parameters around porous-coated dental implants after 3 to 4 years supporting overdentures. J Clin Periodontol 1996; 23:517-22. [PMID: 8811470 DOI: 10.1111/j.1600-051x.1996.tb01819.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In this study, an assessment using modified periodontal indices was done on a group of 48 fully edentulous patients who had each been treated with 3 porous-coated (EndoPore) dental implants and a mandibular overdenture. Parameters assessed included plaque index (PI), sulcular bleeding index (SBI), pocket probing depth (PD), probing attachment level (PAL) and mobility (M) using a Periotest device. At the time of the assessment, all of the patients had passed 3 years of continuous function while 26 had passed 4 years. Approximately 50% of implant surfaces were plaque-free while 79% of surfaces showed no bleeding upon probing. There was no correlation between PI and SBI. The mean PD was 3.1 mm with 64% of sites < or = 3.5 mm. Mobility measurements taken with the Periotest device gave a mean PTV of (-4.35) with 96% of measurements (-0.5). No significant correlations were found between mobility and either PAL or implant length.
Collapse
Affiliation(s)
- D Levy
- Faculty of Dentistry, University of Toronto, Canada
| | | | | | | |
Collapse
|
33
|
Taylor JC, Driscoll CF, Cunningham MD. Failure of a hydroxyapatite-coated endosteal dental implant: a clinical report. J Prosthet Dent 1996; 75:353-5. [PMID: 8642517 DOI: 10.1016/s0022-3913(96)90023-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- J C Taylor
- Walter Reed Army Medical Center, Postgraduate Prosthodontic Program. Washington, D.C., USA
| | | | | |
Collapse
|
34
|
Wang JS. Basic fibroblast growth factor for stimulation of bone formation in osteoinductive or conductive implants. ACTA ORTHOPAEDICA SCANDINAVICA. SUPPLEMENTUM 1996; 269:1-33. [PMID: 8629452 DOI: 10.3109/17453679609155229] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Basic Fibroblast Growth Factor (bFGF) is one of the endogenous factors found in bone matrix. bFGF is a mitogen for many cell types, including osteoblasts and chondrocytes. It can stimulate angiogenesis and osteoblast gene expression. The purpose of this study was to investigate whether exogenous bFGF can stimulate the formation of bone in bone grafts and in a bone graft substitute. In a model using demineralized bone matrix implants for bone induction, a dose of 15 ng bFGF per implant increased the number of chondrocytes and the amount of bone, whereas 1900 ng greatly inhibited cartilage and bone formation. These results are consistent with previous studies with this model, showing that a lower dose of bFGF increased bone calcium content and a higher dose reduced it. Thus, exogenous bFGF can stimulate proliferation during early phases of bone induction. A new device, the bone conduction chamber, was developed for the application of bFGF to bone conductive materials. This model made it possible to demonstrate a difference between the conductive properties of bone grafts and porous hydroxyapatite. bFGF increased bone ingrowth into bone graft inside the chamber and showed a biphasic dose-response curve, so that 8-200 ng per implant (0.4-10 ng/mm3) increased bone ingrowth, but higher or lower doses had no effect. The same doses had the same effects in porous hydroxyapatite. In both bone grafts and porous hydroxyapatite, the highest dose still caused an increase in ingrowth of fibrous tissue. The effect on bone ingrowth was first detected after 6 weeks, regardless if administration of bFGF started at implantation or 2 weeks later, using an implanted minipump. Hyaluronate gel was effective as a slow-release carrier for bFGF. In conclusion, bFGF stimulates bone formation in bone implants, depending on dose and method for administration.
Collapse
Affiliation(s)
- J S Wang
- Department of Orthopedics, University of Lund, Sweden
| |
Collapse
|
35
|
Abstract
The goal of placement of endosseous dental implants is to achieve osseointegration or biointegration of the bone with the implant. A wide variety of materials has been used for these implants, but only a few promote osseointegration and biointegration. Titanium and titanium alloy (Ti6A14V) have been the most widely used of these materials. The surface oxide of titanium appears to be central to the ability of this material to osseointegrate. The oxide limits dissolution of elements and promotes the deposition of biological molecules which allow bone to exist as close as 30 A to the surface of the implant. The details of the ultrastructure of the gap between the implant and bone remain undefined, and the consequences of elements which are released on the interface over time are not known. These areas of investigation are particularly important in defining the differences between commercially pure titanium implants and those made of titanium, aluminium and vanadium. The epithelial interface between the gingiva and titanium appears to contain many of the structural characteristics of the native tooth-gingiva interface, but details are still vague. The connective tissue interface with the titanium appears to be one of tightly fitting tissues rather than adhesion. Ceramic coatings appear to improve the ingrowth of bone and promote chemical integration of the implant with the bone. The characteristics of these coatings are complex and affect the bony response, but the mechanisms remain obscure. The degradation of the coatings is an issue of particular controversy. Progress in dental implantology is likely to continue as the interface between the material and bone is more clearly understood, and biological molecules and artificial tissues are developed.
Collapse
Affiliation(s)
- J C Wataha
- Medical College of Georgia School of Dentistry, Augusta, USA
| |
Collapse
|
36
|
Filiaggi MJ, Pilliar RM, Yakubovich R, Shapiro G. Evaluating sol-gel ceramic thin films for metal implant applications. I. Processing and structure of zirconia films on Ti-6AI-4V. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1996; 33:225-38. [PMID: 8953389 DOI: 10.1002/(sici)1097-4636(199624)33:4<225::aid-jbm3>3.0.co;2-r] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Thin ceramic films or coatings over metallic bone-interfacing implant surfaces have the potential to improve implant performance with respect to implant fixation, wear, or corrosion. In this study, zirconia (ZrO2) thin films formed on Ti-6AI-4V using a polymeric alkoxide-based solgel process were investigated. ZrO2 films of uniform thickness on the order of 100 nm were obtained by dip coating Ti-6AI-4V samples into a zirconium propoxide containing solution using a substrate withdrawal speed ranging from 2 to 8 cm/min and a sol of nominal viscosity approximately 6 cps. These films were essentially free of surface macrodefects but had random submicron "pinholes." X-ray diffraction studies suggested that the films were at least partially crystalline, with some "metastable" cubic and/or tetragonal phases after annealing for 1 h at 500 degrees C. The demonstrated reproducibility of this approach for producing good quality ZrO2 films on Ti-6AI-4V warrants further studies to optimize processing conditions for implant applications.
Collapse
Affiliation(s)
- M J Filiaggi
- Centre for Biomaterials, University of Toronto, Ontario, Canada
| | | | | | | |
Collapse
|
37
|
Kon M, Ishikawa K, Miyamoto Y, Asaoka K. Development of calcium phosphate based functional gradient bioceramics. Biomaterials 1995; 16:709-14. [PMID: 7578775 DOI: 10.1016/0142-9612(95)99699-m] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A functional gradient bioceramic that can function gradually with respect to body tissue was studied by changing the composition of calcium phosphate gradually from the surface to the inside. Diamond powder was spread on the surface of compact hydroxyapatite (HA) powder and fired at 1280 degrees C under reduced pressure, followed by firing under atmospheric conditions. The sintered body thus prepared was dense and alpha-tricalcium phosphate (alpha-TCP: alpha-Ca3(PO4)2) was found on its surface. The content of alpha-TCP gradually decreased with increasing depth from the surface. In contrast, the content of HA increased with increasing depth from the surface. The gradient ratio of alpha-TCP and HA depends on the firing time for each condition, i.e. reduced or atmospheric pressure. The alpha-TCP formation was ascribed to the decomposition of HA due to the spontaneous combustion of diamond powder.
Collapse
Affiliation(s)
- M Kon
- Department of Dental Engineering, School of Dentistry, Tokushima University, Japan
| | | | | | | |
Collapse
|
38
|
Vijayaraghavan TV, Bensalem A. Electrodeposition of apatite coating on pure titanium and titanium alloys. ACTA ACUST UNITED AC 1994. [DOI: 10.1007/bf00776358] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
39
|
Abstract
Osteointegration was defined as a "direct structural and functional connection between ordered living bone and the surface of a load-carrying implant." Although osteointegration was meant originally to describe a biologic fixation of the titanium dental implants, it is now used to describe the attachment of other materials used for dental and orthopedic applications as well. Analyses of material-bone interface showed that osteointegrated implants can have an intervening fibrous layer or direct bone apposition characterized by bone-bonding depending on the composition and surface properties of the biomaterial. This article reviews biologic (host tissue properties and response), biomechanical, and biomaterial factors affecting osteointegration. Biologic factors include the quality of bone. Biomaterial factors include the effect of material composition on the bone-material interface. Suggested areas for future research include determining the correlation between oral bone status and osteoporosis, the effect of gender, age, and endocrine status (e.g., osteoporosis) on implant success or failure, the effect of calcium phosphate coating composition and crystallinity on in vivo performance of implants, the factors contributing to accelerated osteointegration, and development of osteoinductive implants.
Collapse
Affiliation(s)
- R Z LeGeros
- New York University College of Dentistry, New York
| | | |
Collapse
|
40
|
van Noort R, Brown D, Clarke R, Combe EC, Curtis R, Fletcher AM, Lloyd CH, Marquis P, McCabe JF, Nicholson J. Dental materials: 1991 literature review. J Dent 1993; 21:5-30. [PMID: 8425984 DOI: 10.1016/0300-5712(93)90046-s] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Affiliation(s)
- R van Noort
- School of Clinical Dentistry, University of Sheffield
| | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Filiaggi MJ, Pilliar RM, Coombs NA. Post-plasma-spraying heat treatment of the HA coating/Ti-6A1-4V implant system. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1993; 27:191-8. [PMID: 8436575 DOI: 10.1002/jbm.820270208] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The metal/ceramic interface that constitutes an important part of the plasma-sprayed HA-coated Ti-6A1-4V system may, in fact, represent the "weak link" in the implant design. A post-plasma-spray heat treatment to enhance chemical bonding at the metal/ceramic interface and, hence, improve the mechanical properties (interface fracture toughness and tensile coating adhesion strength) of the plasma-sprayed implant system does show promise. In preliminary heat treatment studies, however, any improvements realized were lost due to the chemical instability of the coating in a moisture-laden environment, with a concomitant loss in bonding properties. This deterioration in properties appears to be related to environmentally assisted crack growth as influenced by processing conditions. Still, an ability to improve HA/Ti-6A1-4V bonding through enhanced diffusion bonding was demonstrated, warranting further heat treatment studies involving atmosphere control during processing.
Collapse
Affiliation(s)
- M J Filiaggi
- Centre for Biomaterials, University of Toronto, Ontario, Canada
| | | | | |
Collapse
|
42
|
Arora BK, Worley CM, Guttu RL, Laskin DM. Bone formation over partially exposed implants using guided tissue generation. J Oral Maxillofac Surg 1992; 50:1060-5. [PMID: 1326616 DOI: 10.1016/0278-2391(92)90491-h] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
This pilot study tested whether a semipermeable expanded polytetrafluoroethylene (e-PTFE) membrane could be used to induce new bone to cover the partially exposed surface of titanium and hydroxylapatite (HA)-coated endosseous implants. Twenty threaded titanium and 10 HA-coated implants were placed in the tibia of five mongrel dogs. The implants were placed in a manner that left the cervical 2 to 3 mm exposed. Fifteen implants were used as controls and the rest were covered with an e-PTFE membrane. Animals were killed at 6, 8, and 12 weeks. Those implants covered by the membrane showed a progressive formation of bone on the exposed portion. The threaded titanium control implants showed reactive periosteal bone formation in the adjacent area, but no new bone formation on the exposed threads. The HA-coated controls, however, showed progressive bone formation on the exposed portion. Membrane position appeared to have an effect on the quantity of bone that formed, as those test sites in which there was a collapse of the membrane against the implant showed less new bone than those in which a protected space was created. This study showed that guided tissue generation may be used to induce new bone to form over the exposed portion of an implant, that the amount of new bone is influenced by the width of the space between membrane and implant, and that new bone forms on an exposed HA-coated implant even in the absence of a guiding membrane.
Collapse
Affiliation(s)
- B K Arora
- Department of Oral and Maxillofacial Surgery, University of Alberta, Edmonton
| | | | | | | |
Collapse
|