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At least 613 records · Page 34Linked to original sources
PubMed2003

Tropical chronic pancreatitis.

Tropical chronic pancreatitis (TCP) is a juvenile form of chronic calcific non-alcoholic pancreatitis, seen almost exclusively in the developing countries of the tropical world. The classical triad of TCP consists of abdominal pain, steatorrhoea, and diabetes. When diabetes is present, the condition is called fibrocalculous pancreatic diabetes (FCPD) which is thus a later stage of TCP. Some of the distinctive features of TCP are younger age at onset, presence of large intraductal calculi, more aggressive course of the disease, and a high susceptibility to pancreatic cancer. Pancreatic calculi are the hallmark for the diagnosis of TCP and in non-calcific cases ductal dilation on endoscopic retrograde cholangiopancreatography, computed tomography, or ultrasound helps to identify the disease. Diabetes is usually quite severe and of the insulin requiring type, but ketosis is rare. Microvascular complications of diabetes occur as frequently as in type 2 diabetes but macrovascular complications are uncommon. Pancreatic enzyme supplements are used for relief of abdominal pain and reducing the symptoms related to steatorrhoea. Early diagnosis and better control of the endocrine and exocrine dysfunction could help to ensure better survival and improve the prognosis and quality of life of TCP patients.

Adult↗
PubMed1981

Mutagenic evaluation of 1,1,2,3-tetrachloro-2-propene, a contaminant in pulp mill effluents, using a battery of in vitro mammalian and microbial tests.

The mutagenicity of 1,1,2,3-tetrachloro-2-propene (TCP), a component of chlorinated pulp mill effluents, was investigated with a battery of in vitro mammalian and microbial assays. In fluctuation tests, TCP showed potent mutagenic activity with Salmonella typhimurium strain TA1535 but only very weak activity with Escherichia coli WP2. In Chinese hamster ovary (CHO) cells, TCP without metabolic activation induced chromosome aberrations. This activity was enhanced by the addition of Aroclor 1254-induced rat liver preparation (S9). Endoreduplication was also induced by TCP in the presence of S9. Without activation, TCP caused an increase in the number of sister chromatid exchanges (SCEs), however this increase was eliminated by S9. TCP did not cause DNA damage in CHO cells as measured by alkaline sucrose gradient sedimentation either with or without metabolic activation.

Animals↗
PubMed2001

Degradation behavior of composite pins made of tricalcium phosphate and poly(L,DL-lactide).

Combining a bioactive ceramic with a resorbable polymer may improve the biocompatibility and the osseointegration of degradable fracture fixation devices. This study reports on the mechanical properties and degradation behavior of two composite pins made of poly(L,DL-lactide) and 10 and 30% beta-tricalcium phosphate (TCP), respectively. The pins were compared to a pin made of 100% poly(L,DL-lactide). The failure force, bending strength, and molecular weight were determined during in vitro degradation at 37 degrees C up to 78 weeks. The blending with 10 or 30% beta-TCP decreased the initial mechanical properties and led to an accelerated degradation rate. The pins with 30% TCP lost half of their strength after 16 weeks, i.e. faster than the unmodified pin (40 weeks). The pins with 10% TCP, however, showed a decreased initial strength (128+/-9 MPa) compared to the unmodified pin (152+/-9 MPa) but very similar degradation characteristics. The drop of the molecular weight was not significantly different between the three types of pins. It was concluded that the mechanical requirements for a pin for the fixation of small bony fragments with improved biocompatibility were fulfilled by the composite pin with 10% TCP but not by the pin with 30% TCP.

Biocompatible Materials↗
PubMed2005

Nanoindentation on porous bioceramic scaffolds for bone tissue engineering.

We report nanoindentation mechanical properties measurements on porous ceramic scaffolds made for tissue engineering applications. The scaffolds have been made from tricalcium phosphate (TCP), hydroxyapatite (HA) nanopowder and mixed powders of HA (50 wt%) and TCP (50 wt%) using the polyurethane sponge method, which produces open porous ceramic scaffolds through replication of a porous polymer template. The scaffolds prepared by this method have a controllable pore size and interconnected pore structure. The crystal structures and morphology of porous scaffolds were determined by X-ray diffraction (XRD) and atomic force microscopy (AFM) respectively. Nanoindentation measurements to a depth of 600 nm showed a Young's modulus value of 10.3 GPa for HA+TCP composite scaffolds and 1.5 GPa for TCP scaffolds. The hardness values were 240 MPa for HA+TCP composites and 21 MPa for TCP sample respectively. The results showed that the mechanical properties of the biodegradable scaffolds can be considerably enhanced with the addition of HA while maintaining the interconnected open pores and pore geometry desirable for bone tissue engineering.

Biocompatible Materials↗
PubMed2003

Attachment of human marrow stromal cells to titanium surfaces.

The attachment of human bone marrow stromal cells to titanium alloy (Ti6Al4V) surfaces was investigated. Titanium disks were polished and modified by surface roughening and by passivation in nitric add. Cell attachment to titanium surfaces and tissue culture plastic (TCP) was determined by tetrazolium bromide (MTT) assay at 2, 6, 24, and 48 hours after seeding. Cell proliferation was determined by thymidine incorporation. Attachment on titanium surfaces was 75.6% to 94.9% of attachment on TCP control. The difference between cell attachment on the TCP compared with smooth or rough titanium was statistically significant (P < .05). However, no statistically significant difference was found between attachment to TCP and passivated titanium. Cell proliferation on titanium surfaces after 24 hours was approximately 70% of proliferation on TCP. There was a statistically significant difference (P < .05) between proliferation on tissue culture and smooth and passivated titanium but not on rough titanium. These results indicate that titanium provides a surface that is conducive to cell attachment and that passivating titanium improves cell attachment, approaching levels seen with TCP, a surface specifically developed to enhance cell attachment. Increasing surface roughness results in improved cell proliferation on titanium.

Alloys↗
PubMed2001

Life-cycle effects of sediment-associated 2,4,5-trichlorophenol on two groups of the midge Chironomus riparius with different exposure histories.

Effects of 2,4,5-trichlorophenol (TCP) on life-cycle traits of the midge Chironomus riparius and the ability of the midge to evolve tolerance to TCP were assessed using a reference group and a group preexposed to TCP during three generations, both originating from the same laboratory culture. F1 larvae of these groups were then exposed to nominal TCP concentrations of 51, 177, 355, and 532 micromol TCP/kg dry sediment and a control sediment in a life-cycle experiment. Most studied life-cycle traits (mortality, egg production, life span, male dry wt) were fairly insensitive to TCP, and significant effects were observed only at high (> or = 355 micromol/kg) concentrations. Larval development rate was variable, and in some cases it responded more readily to low TCP concentrations than other life-cycle parameters. Some of the observed responses were attributed to changes in food availability. No clear evidence of tolerance to 2,4,5-trichlorophenol was found, but the preexposed midges produced more eggs than the reference group. They also emerged earlier and at a smaller size than the reference midges. These differences between the midge groups suggest that some changes toward tolerance induction had occurred during the preexposure.

Animals↗
PubMed2005

Platelet-derived growth factor stimulates bone fill and rate of attachment level gain: results of a large multicenter randomized controlled trial.

BACKGROUND: Growth factors are generally accepted to be essential mediators of tissue repair via well-established mechanisms of action that include stimulatory effects on angiogenesis and cellular proliferation, ingrowth, differentiation, and matrix biosynthesis. The aim of this study was to evaluate in a large-scale, prospective, blinded, and randomized controlled clinical trial the safety and effectiveness of purified recombinant human platelet-derived growth factor (rhPDGF-BB) mixed with a synthetic beta-tricalcium phosphate (beta-TCP) matrix for the treatment of advanced periodontal osseous defects at 6 months of healing. METHODS: Eleven clinical centers enrolled 180 subjects, each requiring surgical treatment of a 4 mm or greater intrabony periodontal defect and meeting all inclusion and exclusion criteria. Subjects were randomized into one of three treatment groups: 1) beta-TCP + 0.3 mg/ml rhPDGF-BB in buffer; 2) beta-TCP + 1.0 mg/ml rhPDGF-BB in buffer; and 3) beta-TCP + buffer (active control). Safety data were assessed by the frequency and severity of adverse events. Effectiveness measurements included clinical attachment levels (CAL) and gingival recession (GR) measured clinically and linear bone growth (LBG) and percent bone fill (% BF) as assessed radiographically by an independent centralized radiology review center. The area under the curve (AUC), an assessment of the rate of healing, was also calculated for CAL measurements. The surgeons, clinical and radiographic evaluators, patients, and study sponsor were all masked with respect to treatment groups. RESULTS: CAL gain was significantly greater at 3 months for group 1 (rhPDGF 0.3 mg/ml) compared to group 3 (beta-TCP + buffer) (3.8 versus 3.3 mm; P = 0.032), although by 6 months, this finding was not statistically significant (P = 0.11). This early acceleration of CAL gain led to group 1 exhibiting a significantly greater rate of CAL gain between baseline and 6 months than group 3 as assessed by the AUC (68.4- versus 60.1-mm weeks; P = 0.033). rhPDGF (0.3 mg/ml)-treated sites also had significantly greater linear bone gain (2.6 versus 0.9 mm, respectively; P < 0.001) and percent defect fill (57% versus 18%, respectively; P < 0.001) than the sites receiving the bone substitute with buffer at 6 months. There was less GR at 3 months in group 1 compared to group 3 (P = 0.04); at 6 months, GR for group 1 remained unchanged, whereas there was a slight gain in gingival height for group 3 resulting in comparable GR. There were no serious adverse events attributable to any of the treatments. CONCLUSIONS: To our knowledge, this study is the largest prospective, randomized, triple-blinded, and controlled pivotal clinical trial reported to date assessing a putative periodontal regenerative and wound healing therapy. The study demonstrated that the use of rhPDGF-BB was safe and effective in the treatment of periodontal osseous defects. Treatment with rhPDGF-BB stimulated a significant increase in the rate of CAL gain, reduced gingival recession at 3 months post-surgery, and improved bone fill as compared to a beta-TCP bone substitute at 6 months.

Adult↗
PubMed2006

New composite endpoints to assess efficacy in periodontal therapy clinical trials.

BACKGROUND: Clinical attachment level (CAL) and bone height (radiographic or clinical) are two well-accepted endpoint measures for periodontal clinical trials; however, neither one has been shown to be more predictive of long-term success than the other. We propose using a composite endpoint analysis combining clinical and radiological parameters to assess the beneficial effects on both hard and soft tissues following periodontal therapy using a single statistical test. To address this need, two composite endpoint alternatives are offered as a yardstick for clinical success; each includes the improvement in CAL and either improvement in linear bone growth or percent bone fill. METHODS: The data for composite endpoint analyses were derived from a clinical trial evaluating two concentrations of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) with beta-tricalcium phosphate (beta-TCP) compared to beta-TCP plus buffer as follows: group I, beta-TCP + 0.3 mg/ml rhPDGF-BB; group II, beta-TCP + 1.0 mg/ml rhPDGF-BB; and group III, beta-TCP + buffer. The construction of composite endpoints was based on the greatest values for change, accepted by the U.S. Food and Drug Administration (FDA), for clinical attachment level (DeltaCAL), mean change in radiographic linear bone gain (LBG), and mean radiographic percent bone fill (%BF), with the following dual standards defining a successful clinical result: CAL gain > or =2.67 mm and radiographic LBG > or =1.1 mm at 6 months and CAL gain > or =2.67 mm and radiographic %BF > or =14.1% at 6 months. RESULTS: Group I (beta-TCP + 0.3 mg/ml rhPDGF-BB) demonstrated statistically significant differences from group III (active control) for both composite endpoints. For the CAL/LBG composite endpoint, 61.7% of sites in group I versus 30.4% of sites in group III met the composite endpoint benchmarks (P <0.001). For the CAL/%BF composite endpoint, 70% of sites in group I versus 44.6% of sites in group III met the composite endpoint benchmarks (P = 0.003). A non-significant trend was observed for group II versus group III with 37.9% (P = 0.20) and 55.2% (P = 0.13) of sites meeting the CAL/LBG and CAL/%BF composite endpoints, respectively. These results are further emphasized by findings demonstrating a low correlation between the individual efficacy endpoints (DeltaCAL and %BF; DeltaCAL and LBG) for each of the three treatment groups. CONCLUSIONS: Composite endpoints are advantageous in periodontal clinical trials where no single efficacy endpoint has been established as the most important. A composite endpoint, combining outcome measures of both hard and soft tissue components of the periodontium, may be preferable for assessing efficacy of periodontal regenerative therapies. Two composite endpoints are offered to meet this need.

Alveolar Bone Loss↗
PubMed2003

[Determination method of tricresyl phosphate in polyvinyl chloride].

A simple and rapid method using HPLC was developed for the determination of tricresyl phosphate (TCP) in polyvinyl chloride (PVC) articles. A test sample was extracted with acetonitrile at 37 degrees C overnight. The extract solution diluted with an equivalent amount of water was applied to a Sep-Pak C18 cartridge, and TCP was eluted with acetonitrile-water (2:1) mixture. The eluate was analyzed by HPLC with an Inertsil Ph-3 column, using 65% acetonitrile/water as the mobile phase, with UV detection (264 nm). The calibration curve was rectilinear from 0.5 to 100 micrograms/mL. The recoveries of TCP added to various kinds of PVC articles at the level of 1,000 micrograms/g were 84.7-98.6%. The determination limit of TCP was 50 micrograms/g in samples. This method was applied to products including 3.1, 6.6 and 8.8% TCP and the recoveries of TCP were 87.3-91.4%. This method is very simple, and it seems suitable for a regulatory test.

Chromatography, High Pressure Liquid↗
PubMed2005

Proliferation and differentiation of cultured MC3T3-E1 osteoblasts on surface-layer modified hydroxyapatite ceramic with acid and heat treatments.

Effects of functionally gradient calcium phosphate consisting of hydroxyapatite (HAP) and alpha-tricalcium phosphate (alpha-TCP) on proliferation and differentiation of osteoblasts were evaluated using MC3T3-E1 cells. There were no significant differences in the proliferation of MC3T3-E1 cells among HAP-alpha-TCP functionally gradient calcium phosphate, pure HAP, and cell culture plastic wells. mRNA expressions of type I collagen, alkaline phosphate, and osteocalcine were evaluated as indexes of initial; mid-stage, and late-stage osteoblastic differentiation. Basically, HAP-alpha-TCP functionally gradient calcium phosphate and pure HAP enhanced the expressions of the three markers when compared with that of cell culture plastic wells. For type I collagen and alkaline phosphate expressions, HAP-alpha-TCP functionally gradient calcium phosphate showed the same expression level as pure HAP. For osteocalcine expression, HAP-alpha-TCP functionally gradient calcium phosphate showed a higher level than pure HAP. We concluded, therefore, HAP-alpha-TCP functionally gradient calcium phosphate has good potential to be a bone filler material with high osteoconductivity.

3T3 Cells↗
PubMed2001

Development of a model for bioresorbability of bioceramic microparticles.

Over the past decade, numerous studies have implicated wear particle debris, generated by everyday wear or ceramic implants, as the essential contributors to implant failure [3,4,5,6,7]. We investigated the interactions of ceramic particles (TCP and HA) on cell viability, cell damage, and respiratory burst in a macrophage cell line (RAW 264.7) for a duration of 24, 48, and 72 hours. The results show that cellular protein levels ranged between 0.20-0.3 mg/ml for the duration of the experiment, and there was no difference detected between or among the groups (P < 0.05). Differences in MDA levels (the amount of lipid peroxides formed at the cellular membrane) were not detected at the early time points (24-48 hours). However, with time in culture there is an increase in MDA levels in all groups. There were no differences detected in nitric oxide production between TCP and the control at all phases. The amount of nitric oxide produced by cells treated with Ha decreased slightly at 24 hours. In contrast, at 48 and 72 hours there was a significant increase when compared to the control. Morphological evaluation revealed that cells treated with TCP contained irregular membrane boundaries, and appeared to have cytoplasmic extensions. Many of the macrophages consisted of large vacuoles containing TCP particles. Cells treated with HA also contained irregular cytoplasmic borders with an increase in vacuolization. At 48 hours, the morphology of all groups remained the same, and at 72 hours, many of the cells treated with TCP and HA began to lyse. Overall, RAW 264.7 macrophage cells are capable of ingesting particles of TCP and HA, and after three days in culture the cells begin to show the effects of increased retention of ceramic particles. The results of this investigation can be used as a model for the assessment of the resorbability rate of implantable devices.

Absorbable Implants↗
PubMed2004

[The effect of platelet-rich plasma on new bone formation by augmentation with osseoconductive bone substitute material in beagle dogs].

Animal experiments were carried out with osseoconductive bone substitute beta-tricalcium phosphate (beta-TCP), with the aim of assessing the effect of the growth factors synthesized by platelets on the speed of beta-TCP incorporation and on the quality of newly formed bone. The question arises whether the results attained with this synthetic material approach are comparable to those attained with autologous bone. Defects in the mandibles of beagle dogs were filled with beta-TCP or with the mixture of beta-TCP and platelet rich plasma (PRP) obtained from autologous blood. The quality of the newly formed bone and the effect of PRP were studied by histologic and histomorphometric methods. On the 6th week, bone formation seemed to be more effective when PRP was applied in comparison with beta-TCP alone, but the difference was not significant. On the 12th week bone formation was significantly greater. The results demonstrate that the use of PRP accelerates the remodelling of the synthetic bone-substitute material beta-TCP.

Animals↗
PubMed2004

[Using platelet-rich plasma (PRP) to improve bone regeneration in implant bone defect].

OBJECTIVE: To evaluate the result of bone regeneration due to using PRP in combination with beta-TCP in bone defect adjacent to oral implantation. METHODS: Ten patients (6 males, 4 females, with an average age of 49.6 years) participated in this study. Seven of them underwent maxillary sinus augmentations, and 3 underwent GBR for peri-implant bone defects. PRP + beta-TCP was used in 4 cases and beta-TCP in other 6 as control. X-ray examinations were carried out prior to operation and in 1 week, at 3 months, 6 months after operation. After 4 - 6 months, 3 biopsy specimens were obtained at the time of the second stage operation in each group. RESULTS: Bone grafts healed well without any infection in all cases. Radiographs showed that bone grafts integrated together with the bone. The histological result showed that new bone was formed among particles of beta-TCP in both groups, but in PRP + beta-TCP group denser and better arranged woven bone was observed, and more new bone was formed into the micropores of the particles. CONCLUSIONS: The result in this study implied that PRP in combination with beta-TCP can improve bone regeneration in bone defect adjacent to oral implantation.

Adolescent↗
PubMed2004

Cloning of LjCYC1 gene and nuclear localization of LjCYC1 protein in Lotus japonicus.

The LjCYC1 (Lotus japonicus Cycloidea-like 1) gene, a homolog of CYC (Cycloidea) belonging to the TCP [TB1(teosinte branched 1), CYC, PCFs (PCF1 and PCF2)] gene family and encoding a predicted transcription factor and being proposed controlling different aspects of plant development, was isolated from the papilionaceous plant Lotus japonicus by screening the genomic DNA library, in order to test the functional conservation and divarication of CYC-like genes in legume. Sequence analyses indicate that LjCYC1 gene contains two exons and one intron and encodes a 370-AA peptide LjCYC1. The putative protein, LjCYC1, contains a TCP domain and an R domain, being a member of the CYC/TB1 subfamily of TCP family, and has 39.0% identity with and 42.6% similarity to CYC. LjCYC1-cDNA was cloned through RT-PCR. Different regions of the LjCYC1-cDNA were fused with the report gene GUS and then the fused constructs were transiently expressed in the onion epidermal cells through particle bombardment. Results of GUS and DAPI staining showed that the chimeric proteins with TCP domain were localized within the nucleus, confirming that LjCYC1 may act as a transcription factor. But the TCP domain itself could not confer the nuclear localization because the chimeric proteins with TCP domain alone were dispersed all over the transformed cells.

Amino Acid Sequence↗
PubMed2006

[Micro-particles of bioceramics could cause cell and tissue damage].

We conducted studies to confirm the hypothesis that the cellular damage occurring around implanted biphasic bioceramics could be related to a micro-particles release because of an insufficient sintering. An in vitro cytotoxicity study was performed on four biphasic ceramic (BCP) samples. Without the treatment of extraction medium, a cytotoxicity was observed, although after centrifugation this cytotoxicity disappeared in all samples. (2) Micro-particles of HA, beta-TCP and 40%beta-TCP/60%HA mixture were used for a cell inhibition study. A decrease of cell viability was observed with the increase in particles concentration. At 10000 particles/ cell, the viability and proliferation were completely inhibited. (3) HA, beta-TCP and BCP ceramic granules were implanted in rabbit femoral cavities for 12 weeks. No degradation of HA granules was observed. The degradation was higher for beta-TCP (40%) than for BCP (5%). On the other hand, new bone formation was significantly higher for beta-TCP (21%) and HA (18%) than for BCP (12%). Much more micro-particles were formed around BCP granules than around beta-TCP, and were phagocytosed by macrophages. The release of ceramic micro-particles could be related to the sintering process. BCP ceramics have to be sintered at only 1160 degrees C. Consequently, HA microparticles of BCP ceramic are incompletely sintered and easily released after immersion or implantation. The microparticles could be at the origin of local inflammation and cell damage and could perhaps modify osteogenesis. Particular attention must be paid to this problem with regard to BCP ceramics because of the sintering difficulties of this bioceramic.

Biocompatible Materials↗
PubMed1990

Competitive inhibition of magnesium-induced [3H]N-(1-[thienyl] cyclohexyl)piperidine binding by arcaine: evidence for a shared spermidine-magnesium binding site.

The polyamine competitive antagonist arcaine (1,4-diguanidino-butane) produced complete inhibition of basal [3H]N-(1-[thienyl] cyclohexyl)piperidine ([3H]TCP) binding, with an IC50 value of 4.52 +/- 0.93 microM. Arcaine (5 and 10 microM) produced a decrease in the affinity without a significant change in the receptor density of [3H]TCP binding under equilibrium conditions. In addition, arcaine did not alter either N-methyl-D-aspartate-specific [3H] glutamate or strychnine-insensitive [3H]glycine binding. Furthermore, increasing concentrations of arcaine produced parallel rightward shifts in the concentration-response curves for both spermidine- and magnesium-induced [3H]TCP binding, suggesting that arcaine is a competitive inhibitor of both agonists. Similar rightward shifts were observed for barium- and strontium-induced [3H]TCP binding. In contrast, arcaine decreased the efficacy of glutamate- and glycine-induced [3H]TCP binding without changing their EC50 values, indicating a noncompetitive type of inhibition. These results imply that spermidine and certain divalent cations including magnesium share the same mechanism for enhancing [3H]TCP binding, whereas glutamate and glycine have different sites of action. This is further supported by the additive effect of spermidine when tested in the presence of maximal concentrations of glutamate and glycine. On the other hand, spermidine and magnesium were not additive and, in fact, magnesium was able to block the effects of spermidine under certain conditions. The possibility that magnesium is a partial agonist at the polyamine site is discussed.

Animals↗
PubMed1991

Tricalcium phosphate amino acid capsules as a drug delivery system for steroid hormones.

Several researchers have reported that there are drawbacks in using the current pharmacotherapeutic procedure for the treatment of endocrine insufficiency. Furthermore, such drugs have to be taken on a lifelong basis. Also, long term exposure to drugs seems to be necessary in the treatment of the most common endocrine disorders. Thus, the traditional routes of administration expose the body constantly to large fluctuating levels of drugs. This study presents a possible alternative route of administering the drugs for the treatment of the aforementioned cases. Ceramics, such as, tricalcium phosphate (TCP) have been used extensively in the dental and orthopedic fields. To date, the use of compressed TCP ceramic capsules as drug delivery systems has not been investigated. The objective of this study is to investigate the capability of calcined TCP amino acid-steroid matrix to deliver progesterone (P), in a sustained manner. Microcrystals of TCP were prepared by following standard laboratory procedures. Three different amino acids (cysteine, proline, and lysine) were incorporated (individually or in combination form) into the TCP matrix. Each matrix contained 100 mg of P and the homogeneous material was compressed at 5000 Kg compression load using a French Pressure Cell. The total amount of steroid released was monitored spectrophotometrically. The results of this study suggest that: (i) TCP- amino acid-steroid composites can be used to deliver steroids in a sustained manner. (ii) The amount of steroid released from the matrix system was found to be dependent upon the physiochemical characteristics of the amino acids.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed1989

[An experimental comparative study of hydroxyapatite and tricalcium-phosphate as bone substitutes].

Hydroxyapatite (HAP) and beta tricalcium-phosphate (TCP) were implanted into the femoral distal metaphysis of 18 adult mongrel dogs. X-ray pictures were periodically taken following surgery, and the animals were sacrificed at 2, 4, 8, 12, 24 weeks, and 1, 2 years postoperatively. The undecalcified specimens were stained using Cole HE stain. During 2 years following surgery, both radiological and macroscopic examinations revealed no significant change in either HAP or TCP. In the undecalcified specimens, an apparent change in configuration was only noticed in the TCP, but there was no difference in the degree of new bone formation between HAP and TCP implants. At 2 years postoperatively, the Ca/P ratios of the HAP and TCP implants remained constant. The results of this study therefore suggest that TCP is a promising autograft extender.

Animals↗