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PubMed1996

Using titanium plate or meshplate for chest wall reconstruction: report of 6 cases and literature review.

Titanium plate has been widely used in several surgical fields, such as craniofacial reconstruction and orthopedic prosthesis. This prosthesis has been proved not only with good biocompatibility and mechanical strength, but also with light weight and low radiological interference. From October 1991 to May 1995, 6 patients underwent thoracic cage reconstruction with titanium plate in our hospital. They included 5 females and 1 male, with ages ranging from 26 to 62 years. Four of them suffered from primary chest wall tumors (2 desmoid tumors, a chondrosarcoma, and 1 hemangioma), one had a recurrent chest wall tumor from breast carcinoma, and one had thoracic hypoplasia. The thoracic cage defect ranged from 5 x 6 cm to 10 x 15 cm, and 1 to 3 titanium plates were used for the reconstruction. No paradoxical movement or other prosthesis-related complications have occurred during the follow-up period. We conclude that titanium plate is a good material for thoracic cage reconstruction.

Adult↗
PubMed1991

Comparison of titanium-mesh and porous disc electrodes for epicardial defibrillation.

The object of this study was to compare the effectiveness of chronically implanted porous electrodes with that of smooth mesh titanium electrodes of the same diameter but smaller effective surface area. The criteria used in evaluating the electrodes were (1) acute, subacute, and chronic resistance and (2) acute, subacute, and chronic defibrillation thresholds. Electrode pairs 2.5 cm in diameter were implanted in each of 17 dogs (ten mesh and seven porous). One electrode of each pair was sutured to the right ventricle and one to the left ventricle near the cardiac apex. Defibrillation threshold energy and total resistance were measured at the time of implantation and again 6 and 12 weeks after implantation. The mean initial resistance of the titanium electrodes was 131.7 omega; the mean defibrillation values for the porous electrode implant were 96.9 omega and 7.5 joules, respectively. Three to 6 weeks after implantation, the values for the titanium mesh electrode were 88.9 omega and 12.0 joules, while those for the porous electrode were 59.9 omega and 8.0 joules. In the chronic state, the figures for the titanium mesh electrode were 78.1 omega and 13.0 joules, while those for the porous electrode were 64.3 omega and 8.3 joules. We conclude that defibrillation can be achieved successfully with small epicardial electrodes. The findings suggest that a porous electrode, with its larger effective surface area, has lower electrode/tissue interface resistance in the acute and chronic phases, and, therefore, provides lower defibrillation threshold energy.

Animals↗
PubMed2004

A systematic review of the influence of different titanium surfaces on proliferation, differentiation and protein synthesis of osteoblast-like MG63 cells.

OBJECTIVES: Titanium is the standard material for dental and orthopaedical implants. The good biocompatibility has been proven in many experimental and clinical investigations. Different titanium topographies were tested in vitro using different cell culture models. The aim of this systematic review was to evaluate and summarize the medical/dental literature to assess on which kind of titanium surface structure the osteoblast-like osteosarcoma cells MG63 show the best proliferation and differentiation rate, and the best protein synthesis. METHODS: A systematic search was carried out using different on-line databases (PubMed, Web of Science, Cochrane Library, International Poster Journal), supplemented by handsearch in selected journals and by examination of the bibliographies of the identified articles. Inclusion and exclusion criterias were applied when considering relevant articles. Studies which met the inclusion criteria were included and data extraction was undertaken by one reviewer. RESULTS: The search yielded 348 references. Nine articles referring to nine different studies were relevant to our question. Additionally 8 less relevant articles were identified. It was found that regularly textured surfaces of pure titanium with R(a) values (average roughness) of around 4 mum are well-accepted by MG63 cells. CONCLUSIONS: The surfaces and culture conditions vary widely. Therefore it is still difficult to recommend one particular surface. It seems that there are no differences in cell proliferation and differentiation on surfaces treated by blasting and etching. Standardization in fabrication and size of the different test surfaces as well as homogeneity in culture times and plating densities should be aspects for future research.

Algorithms↗
PubMed1985

Study of titanium screws as retrograde fillings using bacteria and dye.

The tightness of retrograde titanium screw fillings and retrograde amalgam fillings was compared in 17 human, single-rooted teeth using Serratia marcescens bacteria in vitro. The root canals were subjected to instrumentation and irrigation, after which 2 mm was cut off from the apical end. Eight of the teeth were sealed using retrograde titanium screw fillings and nine using retrograde amalgam fillings. The teeth were suspended by means of wires in test tubes, with the crowns upwards and the roots immersed in trypticase soy broth. Suspensions of Serratia marcescens bacteria were placed in the root canals, and samples from the broth were plated daily. The bacteria penetrated the apical titanium screw seals in 2 to 7 days, and the retrograde amalgam fillings readily on the first day. Thus, the titanium screws seemed to provide a tighter seal. Staining with India ink showed that penetration had occurred at the tooth-filling margin and that the instrumentation had not caused any fractures to the roots.

Apicoectomy↗
PubMed1988

Corrosion current and pH rise around titanium coupled to dental alloys.

Corrosion reactions around titanium, usually considered biologically inert, might be provoked by coupling it galvanically with more corrodible dental alloys. Experiments in vitro simulating the conditions of a titanium dental implant or root canal post coupled to an amalgam filling, demonstrated corrosion current densities up to 31 microA/cm2, anodic pH values around the amalgam down to 2, and cathodic pH values around the titanium up to 10. The amounts of tin released by the enhanced corrosion of amalgam might contribute measurably to the daily intake of this element; the corrosion current generated reached values known to cause taste sensations. If the buffer systems of adjacent tissues in vivo are not able to cope with the high pH generated around the titanium, local tissue damage may ensue; this relationship is liable to be overlooked, as it leaves no evidence in the form of corrosion products.

Corrosion↗
PubMed1995

Immunocompetent cells adjacent to stainless steel and titanium miniplates and screws.

Subepithelial soft tissue and bone obtained from the implant bed in the vicinity of stainless steel and titanium miniplates and screws were evaluated with respect to the presence of immunocompetent cells. The study included tissue specimens from 19 patients, in whom the implants (14 stainless steel and 5 titanium) had been in situ for more than 6 months. The ABC (avidin-biotin-complex) immunoperoxidase staining technique using monoclonal antibodies defining T lymphocytes (CD3+), macrophages (CD11c+) and Class II MHC (HLA-DR) was performed on EDTA demineralized, frozen bone tissue, and on fresh frozen soft tissue specimens. The results showed scattered T lymphocyte clusters, small numbers of macrophages and abundant expression of HLA-DR in the soft tissue adjacent to both stainless steel and titanium implants. There was no substantial difference in tissue reactions between implants of the two materials. The demineralized bone sections disclosed presence of immunocompetent cells in the connective tissue lining the periphery of the screw holes. Metal particles were seen in both the soft tissue and the bone specimens. We conclude that a mild tissue reaction takes place in the vicinity of miniplates and screws of stainless steel and titanium, and that the intensity of the reaction indicates that the implants are well tolerated by the host tissue.

Adolescent↗
PubMed1995

Effect of titanium on selected oral bacterial species in vitro.

Titanium granules were tested for their antibacterial effect on strains of Streptococcus sanguis, Streptococcus mitis, Actinomyces naeslundii, Haemophilus parainfluenzae, Fusobacterium spp. and Prevotella intermedia in comparison with amalgam and two of its components, copper and tin. Glass beads were used as controls. The number of viable bacteria was estimated in samples exposed to the various materials for 1, 3, 6 and 24 h, respectively, and the viable counts were related to the baseline value. Titanium showed low antibacterial effect on the species tested. Copper and amalgam showed an expressed toxicity to all species and differed significantly from titanium and glass particles. Gram positive Streptococcus spp. and A. naeslundii showed a lower susceptibility to the metals than the Gram negative species. The antibacterial effect of copper and amalgam test particles on S. sanguis and P. intermedia was significantly decreased in the presence of serum. This study showed that some metals have a toxic effect in vitro on oral bacteria, a fact that may play a role in plaque formation when these materials are used for dental restorations. Titanium did not have a similar antibacterial effect.

Actinomyces↗
PubMed2005

Corrosion resistance and biocompatibility of a new porous surface for titanium implants.

Alterations of the commercially pure titanium (cpTi) surface may be undertaken to improve its biological properties. The aim of this study was to investigate the biocompatibility of cpTi when submitted to a new, porous titanium, surface treatment (porous Ti). Five types of surface treatments, namely sintered microspheres porous titanium (porous Ti), titanium plasma spray (TPS), hydroxyapatite (HA), sandblasted and acid etched (SBAE), and resorbable blast medium, sandblasted with hydroxyapatite (RBM) were made. In the experimental methods, the corrosion potentials were measured over time, and then a linear sweep voltammetric analysis measured the polarization resistances and corrosion currents. For biocompatibility evaluation, MG63 osteoblast-like cells were used. Cell morphology, cell proliferation, total protein content, and alkaline phosphatase (ALP) activity were evaluated after 2 h, and after 2, 4 and 7 d. Porous Ti and SBAE showed a better corrosion resistance, with a weak corrosion current and a high polarization resistance, than the other surfaces. Cell attachment, cell morphology, cell proliferation, and ALP synthesis were influenced by the surface treatments, with a significant increase observed of the activity of osteoblast cells on the porous coating (porous Ti). Based on these results, it is suggested that the porous Ti surface has a significantly better biocompatibility than the other surface treatments and an excellent electrochemical performance.

Analysis of Variance↗
PubMed2000

Clinical experiences of CNC-milled titanium frameworks supported by implants in the edentulous jaw: 1-year prospective study.

BACKGROUND: A new type of titanium framework has been introduced, but so far no clinical reports have been made in this treatment modality. PURPOSE: The aim of this study was to report the clinical performance of implant-supported prostheses with computer numeric controlled (CNC)-milled titanium frameworks in the edentulous jaw and to compare the results with prostheses provided with conventional cast frameworks during the first year of function. MATERIAL AND METHODS: A consecutive group of 65 patients with 67 prostheses were provided with CNC-milled titanium frameworks in 23 upper and 44 lower jaws. During the same period, 61 consecutive patients were treated on a routine basis with 31 upper and 31 lower conventional gold alloy casting prostheses. Clinical and radiographic 1-year data were collected for both the test and control groups. RESULTS: A total of 14 of 729 inserted implants were lost during the follow-up period (1.9%). All prostheses were functioning after 1 year except a conventional prosthesis with a cast framework, which was replaced by an implant-supported over-denture due to implant loss. The 1-year cumulative survival rate (CSR) was 100% and 97.8% for CNC prostheses and implants, respectively. The corresponding CSR for the control group was 98.3% and 98.3%, respectively. Few problems were reported in both groups, and the clinical and the radiologic performances were similar for both groups. No mechanical complications except some resin veneer fractures (n = 6) were observed. The mean marginal bone loss for the test group during the first year in function was 0.4 mm (SD = 0.35) and 0.4 mm (SD = 0.33) in the upper and lower jaws, respectively. A similar pattern of bone reaction was also observed in the control group. CONCLUSION: CNC-milled titanium frameworks can be used as an alternative to conventional castings in the edentulous jaw, presenting similar clinical and radiologic performances as conventional cast frameworks during the first year of function.

Adult↗
PubMed2000

A histomorphometric and biomechanical study of the effect of delayed titanium implant placement in irradiated rabbit bone.

BACKGROUND: The time interval from irradiation to implant surgery has been considered an impact factor for implant integration in irradiated bone and the importance of a long interval between the radiation trauma and reconstructive bone surgery has been suggested. PURPOSE: The present study was undertaken to histomorphometrically and biomechanically analyze the effect of delayed implant placement on bone healing around titanium implants in irradiated bone. MATERIALS AND METHODS: Rabbits were given a single dose of 15 Gy Cobalt60 radiation to one hind leg, the other hind leg serving as a control. Titanium screws were inserted into the femur and tibia directly and at 12 weeks and 52 weeks after irradiation. The implants were evaluated after a healing time of 8 weeks. The torques necessary for removal of the implants were measured. Histomorphometry with respect to bone-metal contact and amount of bone surrounding the implants was performed. RESULTS: The biomechanical force necessary to unscrew the titanium implants in the irradiated bone was significantly increased after a resting period of 1 year between irradiation and implant placement, compared to direct implant placement. The histomorphometric evaluation showed an improvement of bone healing around the implants in the irradiated bone, both after a resting period of 12 weeks and after 1 year compared to direct implant placement. CONCLUSIONS: It is concluded that a relatively long interval between irradiation and reconstructive bone surgery will improve osseointegration of titanium implants in irradiated rabbit bone.

Animals↗
PubMed2003

Short-term bone response to titanium implants coated with thin radiofrequent magnetron-sputtered hydroxyapatite in rabbits.

BACKGROUND: It has been suggested that calcium phosphate (CaP) coatings initiate faster bone growth around implants. A major concern about the viable use of these coatings has been their biologic performance related to the coating characteristics. PURPOSE: The purpose of this study was to investigate the early bone response to micron- and submicron-thick hydroxyapatite (HA) coatings in cortical and trabecular bone. MATERIALS AND METHODS: CaP coatings were manufactured by magnetron sputtering. Heat treatment was subsequently used to increase the crystallinity of the coatings. Coatings were characterized by x-ray diffraction, Fourier transform infrared spectroscopy, inductively coupled plasma optical emission spectroscopy (ICP-OES), and stylus profilometry. Four types of CaP-coated implants were used (0.1 microm and 2.0 microm amorphous; 0.1 microm and 2.0 microm crystalline); uncoated machined commercially pure titanium implants served as controls. Four hundred eighty implants were randomly placed in 60 rabbits. Ten animals were followed up for 1 week, 10 for 3 weeks, and 40 for 6 weeks. The bone response was histomorphometrically evaluated. RESULTS: Coatings with a CaP ratio very close to that of HA were produced. Crystalline coatings significantly improved the early bone-implant contact whereas the amorphous-coated implants behaved similarly to uncoated titanium. CONCLUSIONS: Crystalline CaP coatings 100 nm thick on titanium implants elicited an improved early bone response compared with that of uncoated titanium implants. No further improvement in the bone response was observed with 2 microm coatings.

Animals↗
PubMed2005

The human bone-oxidized titanium implant interface: A light microscopic, scanning electron microscopic, back-scatter scanning electron microscopic, and energy-dispersive x-ray study of clinically retrieved dental implants.

BACKGROUND: Surface modification of titanium implants by anodic oxidation may lead to enhanced bone integration. For instance, in vivo studies have demonstrated formation of more bone contacts in less time than for turned control implants. In addition, oxidized implants have shown a higher resistance to torque forces, indicating a strong interlock between bone and the oxide layer. However, the structure of the oxidized titanium-bone interface in high resolution is not known. PURPOSE: The aim of the study was to analyze the human bone-oxidized titanium interface at a high-resolution level. Of particular interest was the relationship between bone tissue and the pores of the surface oxide. MATERIALS AND METHODS: Twelve clinically retrieved implants with an oxidized surface (TiUnite, Nobel Biocare AB, Göteborg, Sweden) were used. Seven were regular dental implants and five were experimental mini-implants and had been subjected to immediate, early, or no loading. They were retrieved after 5 to 9 months of healing and were processed and analyzed using light microscopy, scanning electron microscopy (SEM) in normal and back-scatter (BS-SEM) modes, and energy-dispersive x-ray (EDX) analysis techniques. RESULTS: Bone formation was observed to occur from adjacent bone structures toward the implant surface, and it was evident that bone formation had occurred at the implant surface. SEM, BS-SEM, and EDX revealed that mineralized bone had grown into the pores of the surface oxide layer, including pores with small diameters (< 2 microm). CONCLUSIONS: The clinically retrieved oxidized implants showed evidence of bone growth into the pores of the surface oxide layer. The findings indicate the establishment of a strong interlock between the bone and the oxidized titanium implant, which is suggested to be beneficial for clinical performance.

Coated Materials, Biocompatible↗
PubMed2005

Oxidized titanium implants in reconstructive jaw surgery.

BACKGROUND: Rehabilitation with implant-supported bridges in patients with insufficient bone volumes may require bone reconstructive procedures in conjunction with or prior to implant placement. Clinical follow-up studies using turned titanium and bone grafts have demonstrated higher failure rates than when used in nongrafted patients. Improved bone integration has been demonstrated for oxidized titanium implants; however, their clinical performance in bone reconstruction situations is not known. PURPOSE: This study was performed to analyze the survival and stability of oxidized titanium implants placed in patients subjected to reconstructive jaw surgery at one clinic. MATERIALS AND METHODS: Two hundred oxidized titanium implants (Mk III, TiUnite, Nobel Biocare AB, Göteborg, Sweden) were placed in 47 patients in conjunction with or secondary to six different reconstructive procedures owing to insufficient bone volume. In all six groups, implant stability was assessed by resonance frequency analysis and manually checked for rotation stability at implant insertion, at the time of abutment connection, and after a minimum of 12 months of loading of the prosthetic construction. Periapical radiographs were taken after a minimum of 12 months of loading (mean 21 months) for evaluation of the marginal bone levels. The mean clinical follow-up period was 30 months. RESULTS: Of the 200 implants, 199 were considered osseointegrated at the time of abutment surgery. At the 12-month postloading follow-up, another two implants were considered not stable. Three implants (1.5%) were ranked as unsuccessful. CONCLUSION: Clinical experience with 200 consecutive oxidized implants in various reconstruction situations shows a successful outcome, with only three failures (1.5%) during a mean follow-up period of 30 months.

Adolescent↗
PubMed1988

Efficacy of plasma-sprayed tricalcium phosphate in enhancing the fixation of smooth titanium intramedullary rods.

The osseous tissue response to intramedullary rods plasma-sprayed with TCP was investigated. TCP-sprayed smooth titanium rods and unsprayed controls were bilaterally implanted into the medullary canals of rabbit tibiae. Rabbits in the short-term study were sacrificed at 3 weeks; rabbits in the long-term study were sacrificed at 12 weeks. Pull-out tests were performed and histological sections prepared. The TCP-sprayed titanium rods exhibited significantly higher pull-out strengths than unsprayed contralateral rods at both 3 and 12 weeks, suggesting the bonding of bone to the TCP layer. The TCP-sprayed titanium rods at 3 weeks showed significantly greater osseous tissue response than unsprayed contralateral controls. At 12 weeks, the osseous tissue response was greater than at 3 weeks, and, surprisingly, the response to TCP-sprayed and unsprayed titanium rods was comparable.

Animals↗
PubMed1986

Granulomatous disease associated with pulmonary deposition of titanium.

A patient presented with granulomatous lung disease associated with the pulmonary deposition of various metallic particles. To evaluate the relation between the metallic dust and the granulomatous process, lymphocyte transformation tests to aluminium sulphate, titanium chloride, beryllium sulphate, and nickel sulphate were performed. A lymphocyte proliferative response to titanium chloride was observed on two separate occasions; no responses to the other metals were shown. These results are consistent with hypersensitivity to titanium, and suggest, in this individual, a possible aetiological role between the inhalation of titanium and a granulomatous disease process.

Bronchi↗
PubMed1998

Spetzler titanium aneurysm clips: compatibility at MR imaging.

To evaluate the compatibility of a commercially pure titanium aneurysm clip associated with magnetic resonance (MR) imaging at 1.5 T. Artifacts of the Spetzler titanium aneurysm clip were compared with those produced by six different nonferromagnetic aneurysm clips. With the titanium clip, no magnetic attraction was present, heating was minor, and the artifacts involved a small signal void. With the six other aneurysm clips, artifacts were larger. The presence of Spetzler titanium aneurysm clips is safe at MR imaging at 1.5 T or less.

Artifacts↗
PubMedDate not supplied

Investigation of the stability of coated titanium microparticles used in sunscreens.

Due to its UV-light-absorbing properties, titanium dioxide is used in many sunscreen products. However, concern has been raised about a possible photocatalytic activity of titanium dioxide on living tissues. To reduce potential adverse effects, titanium dioxide used in cosmetic preparations is often coated. The coating should be stable under conditions of use. In order to verify the coating stability, sunscreen-grade-coated titanium microparticles were investigated by laser-induced plasma spectroscopy. No changes in the mechanical stability of the coated microparticles could be detected during the manufacturing and penetration of the sunscreen. Applying strong forces on the microparticles by centrifugation, exceeding by far in use conditions, resulted only in small changes in the coating.

Aluminum↗
PubMed2004

Collagen type I prevents glyoxal-induced apoptosis in osteoblastic cells cultured on titanium alloy.

Advanced glycation end products (AGEs) irreversibly cross-link proteins with sugars and accumulate at a higher age and in diabetes, processes which can interfere with the integration of implants into the tissue. Glyoxal is a highly reactive glycating agent involved in the formation of AGEs and is known to induce apoptosis, as revealed by the upregulation of caspase-3 and fractin (caspase-3 being a key enzyme activated during the late stage of apoptosis and fractin being a caspase-cleaved actin fragment). In this study, we investigated the influence of collagen type I coating on the cytotoxic effect of glyoxal on rat calvarial osteoblastic cells and on human osteosarcoma cells (Saos-2) grown on titanium alloy, Ti6Al4V. Activation of caspase-3 and fractin was measured by counting immunohistochemically stained cells and by flow cytometry with propidium iodide (detection of the apoptosis indicating a sub-G1 peak). Our results showed an increased number of apoptotic osteoblasts after incubation with glyoxal on Ti6Al4V discs. However, the number of apoptotic cells on collagen-coated titanium was significantly smaller than on uncoated titanium after the same treatment. The present findings demonstrate that osteoblasts treated with glyoxal undergo apoptosis, whereas collagen type I coating of titanium alloys (used for implants) has an antiapoptotic function.

Alloys↗