The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
Nureddin Ashammakhi - One of the best experts on this subject based on the ideXlab platform.
-
Histomorphometric analysis of poly-L/D-lactide 96/4 sutures in the gastrocnemius tendon of rabbits.
The International journal of artificial organs, 2006Co-Authors: Jarmo Kangas, Pertti Törmälä, Timo Waris, Ari Pajala, Juhana Leppilahti, Jorma Ryhänen, Satu Länsman, Nureddin AshammakhiAbstract:BACKGROUND Common Achilles tendon ruptures are not usually fixed by bioabsorbable sutures due to limitations in their strength retention properties. Modern technology has made it possible to develop bioabsorbable sutures with prolonged strength retention. AIMS To evaluate histologically tissue reactions of poly-L/D-lactide (PLDLA) sutures implanted in Achilles tendon of rabbits. MATERIAL AND METHODS Fifteen rabbits were evaluated at 2, 6 and 12 weeks postoperatively, with five rabbits in each follow-up group. PLDLA monofilament sutures were implanted into the medial gastrocnemius tendon. Polyglyconate monofilament sutures with similar diameter (Maxon 4-0, Cyanamid of Great Britain Ltd., Gosport, UK) were implanted in the contralateral gastrocnemius tendon. The histology was studied in hard-resin embedded samples. The thickness of the formed fibrous tissue capsule was determined histomorphometrically. RESULTS PLDLA led to formation of significantly thinner fibrous tissue capsule than Maxon sutures of the same diameter. Median thickness (PLDLA vs. Maxon) at two weeks was 5.26 vs.13.22 microm, at six weeks 11.66 vs. 80.97 microm, and at 12 weeks 10.63 vs. 17.59 microm (p
-
Microscopical Characterization of Poly-L/D-Lactide (PLDLA) 96/4 Sutures in the Achilles Tendon of Rabbits
Wound Repair and Regeneration, 2005Co-Authors: Jarmo Kangas, Timo Waris, Ari Pajala, Juhana Leppilahti, Jorma Ryhänen, Satu Länsman, P. Törmälä, Nureddin AshammakhiAbstract:Common Achilles tendon ruptures are usually not fixed by absorbable sutures due to limitations in their strength properties. Modern technology has made it possible to develop bioabsorbable sutures with prolonged strength retention. To evaluate histologically tissue reactions and biodegradation of poly-L/D-lactide (PLDLA) sutures implanted in Achilles tendon of rabbits. Fifteen rabbits were operated on and killed within a time schedule of 2, 6 and 12 weeks, with five rabbits in per period. PLDLA monofilament sutures (Tampere University of Technology, Tampere, Finland) were implanted inside the rabbit medial gastrocnemius tendon for biocompatibility testing. Polyglyconate (4.0) monofilament sutures (Maxon®, Cyanamid of Great Britain Ltd., Gosport, UK) with the same diameter were implanted in the contralateral tendon. The histology was studied in hard-resin embedded samples and the thickness of the encapsule membrane was determined histomorphometrically. PLDLA have significantly smaller capsule formation around each fiber in tendon than Maxon® sutures. The mean capsule thicknesses around PLDLA sutures was 5.26, 11.66, and 10.63 after 2, 6, and 12 weeks respectively. The mean capsule thicknesses around Maxon® sutures was 13.22, 80.97, and 17.59 after 2, 6, and 12 weeks, respectively. In conclusion, by 12 weeks the PLDLA sutures implanted intratendineously formed thinner fibrous capsule than Maxon® sutures of same diameter. The suture materials were not degraded by 12 weeks. Acknowledgments: Research funds from the Technology Development Center in Finland (TEKES, Biowaffle Project 40274/03 and MFM Project 424/31/04), the European Commission (EU Spare Parts Project QLK6-CT-2000-00487), the Academy of Finland (Project 73948) and the Ministry of Education (Graduate School of Biomaterials and Tissue Engineering) are greatly appreciated.
-
strength retention properties of self reinforced poly l lactide sr plla sutures compared with polyglyconate Maxonr and polydioxanone pds sutures an in vitro study
Biomaterials, 2002Co-Authors: Pirkka Mäkelä, Pertti Törmälä, Timo Waris, Timo Pohjonen, Nureddin AshammakhiAbstract:Abstract Recent developments in manufacturing techniques have led to the development of strong bioabsorbable materials such as self-reinforced poly l -lactide (SR-PLLA) sutures. The aim of the study was to investigate the mechanical properties of SR-PLLA sutures in comparison with polyglyconate (Maxon R ) and polydioxanone (PDS) sutures in vitro. Sutures made of SR-PLLA (0.3, 0.5 and 0.7 mm ∅), Maxon R (0.3 and 0.5 mm ∅) and PDS (0.3 and 0.5 mm ∅) were studied by immersion in phosphate-buffered distilled water (pH 7.4) at 37°C for 40 weeks. The breaking force of straight sutures and suture knots was measured. Tensile strength and percentage elongation were calculated. Means, standard deviations, differences between means, and confidence intervals for differences between means were evaluated. SR-PLLA, PDS and Maxon R sutures of 0.3 and 0.5 mm ∅ were of comparable initial tensile strength. Initial knot tensile strength values were lower than those of their counterpart straight sutures. Maxon R sutures had lost their tensile strength by 12 weeks; PDS sutures by 20 weeks. SR-PLLA sutures of 0.3 mm ∅ had a strength of 161.6 MPa and those of 0.5 mm ∅ had a strength of 134 MPa at 40 weeks. The highest percentage elongation of straight sutures (62.8% and 62%) was exhibited by PDS; the lowest by SR-PLLA (35.6% and 35%). In loop tests, PDS showed the highest percentage elongation (43.7% and 58.1%) and SR-PLLA had the lowest values (19.7% and 33%). SR-PLLA sutures had the most prolonged strength retention in vitro, but the lowest elongation (elasticity). Compared with straight sutures, knots had lower tensile strength and elongation values. SR-PLLA sutures can be applied to the closure of wounds that need prolonged support, such as bone.
-
Comparison of strength properties of poly-L/D-lactide (PLDLA) 96/4 and polyglyconate (Maxon) sutures: in vitro, in the subcutis, and in the achilles tendon of rabbits.
Journal of biomedical materials research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.
-
comparison of strength properties of poly l d lactide pldla 96 4 and polyglyconate Maxon sutures in vitro in the subcutis and in the achilles tendon of rabbits
Journal of Biomedical Materials Research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.
Jarmo Kangas - One of the best experts on this subject based on the ideXlab platform.
-
Histomorphometric analysis of poly-L/D-lactide 96/4 sutures in the gastrocnemius tendon of rabbits.
The International journal of artificial organs, 2006Co-Authors: Jarmo Kangas, Pertti Törmälä, Timo Waris, Ari Pajala, Juhana Leppilahti, Jorma Ryhänen, Satu Länsman, Nureddin AshammakhiAbstract:BACKGROUND Common Achilles tendon ruptures are not usually fixed by bioabsorbable sutures due to limitations in their strength retention properties. Modern technology has made it possible to develop bioabsorbable sutures with prolonged strength retention. AIMS To evaluate histologically tissue reactions of poly-L/D-lactide (PLDLA) sutures implanted in Achilles tendon of rabbits. MATERIAL AND METHODS Fifteen rabbits were evaluated at 2, 6 and 12 weeks postoperatively, with five rabbits in each follow-up group. PLDLA monofilament sutures were implanted into the medial gastrocnemius tendon. Polyglyconate monofilament sutures with similar diameter (Maxon 4-0, Cyanamid of Great Britain Ltd., Gosport, UK) were implanted in the contralateral gastrocnemius tendon. The histology was studied in hard-resin embedded samples. The thickness of the formed fibrous tissue capsule was determined histomorphometrically. RESULTS PLDLA led to formation of significantly thinner fibrous tissue capsule than Maxon sutures of the same diameter. Median thickness (PLDLA vs. Maxon) at two weeks was 5.26 vs.13.22 microm, at six weeks 11.66 vs. 80.97 microm, and at 12 weeks 10.63 vs. 17.59 microm (p
-
Microscopical Characterization of Poly-L/D-Lactide (PLDLA) 96/4 Sutures in the Achilles Tendon of Rabbits
Wound Repair and Regeneration, 2005Co-Authors: Jarmo Kangas, Timo Waris, Ari Pajala, Juhana Leppilahti, Jorma Ryhänen, Satu Länsman, P. Törmälä, Nureddin AshammakhiAbstract:Common Achilles tendon ruptures are usually not fixed by absorbable sutures due to limitations in their strength properties. Modern technology has made it possible to develop bioabsorbable sutures with prolonged strength retention. To evaluate histologically tissue reactions and biodegradation of poly-L/D-lactide (PLDLA) sutures implanted in Achilles tendon of rabbits. Fifteen rabbits were operated on and killed within a time schedule of 2, 6 and 12 weeks, with five rabbits in per period. PLDLA monofilament sutures (Tampere University of Technology, Tampere, Finland) were implanted inside the rabbit medial gastrocnemius tendon for biocompatibility testing. Polyglyconate (4.0) monofilament sutures (Maxon®, Cyanamid of Great Britain Ltd., Gosport, UK) with the same diameter were implanted in the contralateral tendon. The histology was studied in hard-resin embedded samples and the thickness of the encapsule membrane was determined histomorphometrically. PLDLA have significantly smaller capsule formation around each fiber in tendon than Maxon® sutures. The mean capsule thicknesses around PLDLA sutures was 5.26, 11.66, and 10.63 after 2, 6, and 12 weeks respectively. The mean capsule thicknesses around Maxon® sutures was 13.22, 80.97, and 17.59 after 2, 6, and 12 weeks, respectively. In conclusion, by 12 weeks the PLDLA sutures implanted intratendineously formed thinner fibrous capsule than Maxon® sutures of same diameter. The suture materials were not degraded by 12 weeks. Acknowledgments: Research funds from the Technology Development Center in Finland (TEKES, Biowaffle Project 40274/03 and MFM Project 424/31/04), the European Commission (EU Spare Parts Project QLK6-CT-2000-00487), the Academy of Finland (Project 73948) and the Ministry of Education (Graduate School of Biomaterials and Tissue Engineering) are greatly appreciated.
-
Comparison of strength properties of poly-L/D-lactide (PLDLA) 96/4 and polyglyconate (Maxon) sutures: in vitro, in the subcutis, and in the achilles tendon of rabbits.
Journal of biomedical materials research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.
-
comparison of strength properties of poly l d lactide pldla 96 4 and polyglyconate Maxon sutures in vitro in the subcutis and in the achilles tendon of rabbits
Journal of Biomedical Materials Research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.
Timo Waris - One of the best experts on this subject based on the ideXlab platform.
-
Histomorphometric analysis of poly-L/D-lactide 96/4 sutures in the gastrocnemius tendon of rabbits.
The International journal of artificial organs, 2006Co-Authors: Jarmo Kangas, Pertti Törmälä, Timo Waris, Ari Pajala, Juhana Leppilahti, Jorma Ryhänen, Satu Länsman, Nureddin AshammakhiAbstract:BACKGROUND Common Achilles tendon ruptures are not usually fixed by bioabsorbable sutures due to limitations in their strength retention properties. Modern technology has made it possible to develop bioabsorbable sutures with prolonged strength retention. AIMS To evaluate histologically tissue reactions of poly-L/D-lactide (PLDLA) sutures implanted in Achilles tendon of rabbits. MATERIAL AND METHODS Fifteen rabbits were evaluated at 2, 6 and 12 weeks postoperatively, with five rabbits in each follow-up group. PLDLA monofilament sutures were implanted into the medial gastrocnemius tendon. Polyglyconate monofilament sutures with similar diameter (Maxon 4-0, Cyanamid of Great Britain Ltd., Gosport, UK) were implanted in the contralateral gastrocnemius tendon. The histology was studied in hard-resin embedded samples. The thickness of the formed fibrous tissue capsule was determined histomorphometrically. RESULTS PLDLA led to formation of significantly thinner fibrous tissue capsule than Maxon sutures of the same diameter. Median thickness (PLDLA vs. Maxon) at two weeks was 5.26 vs.13.22 microm, at six weeks 11.66 vs. 80.97 microm, and at 12 weeks 10.63 vs. 17.59 microm (p
-
Microscopical Characterization of Poly-L/D-Lactide (PLDLA) 96/4 Sutures in the Achilles Tendon of Rabbits
Wound Repair and Regeneration, 2005Co-Authors: Jarmo Kangas, Timo Waris, Ari Pajala, Juhana Leppilahti, Jorma Ryhänen, Satu Länsman, P. Törmälä, Nureddin AshammakhiAbstract:Common Achilles tendon ruptures are usually not fixed by absorbable sutures due to limitations in their strength properties. Modern technology has made it possible to develop bioabsorbable sutures with prolonged strength retention. To evaluate histologically tissue reactions and biodegradation of poly-L/D-lactide (PLDLA) sutures implanted in Achilles tendon of rabbits. Fifteen rabbits were operated on and killed within a time schedule of 2, 6 and 12 weeks, with five rabbits in per period. PLDLA monofilament sutures (Tampere University of Technology, Tampere, Finland) were implanted inside the rabbit medial gastrocnemius tendon for biocompatibility testing. Polyglyconate (4.0) monofilament sutures (Maxon®, Cyanamid of Great Britain Ltd., Gosport, UK) with the same diameter were implanted in the contralateral tendon. The histology was studied in hard-resin embedded samples and the thickness of the encapsule membrane was determined histomorphometrically. PLDLA have significantly smaller capsule formation around each fiber in tendon than Maxon® sutures. The mean capsule thicknesses around PLDLA sutures was 5.26, 11.66, and 10.63 after 2, 6, and 12 weeks respectively. The mean capsule thicknesses around Maxon® sutures was 13.22, 80.97, and 17.59 after 2, 6, and 12 weeks, respectively. In conclusion, by 12 weeks the PLDLA sutures implanted intratendineously formed thinner fibrous capsule than Maxon® sutures of same diameter. The suture materials were not degraded by 12 weeks. Acknowledgments: Research funds from the Technology Development Center in Finland (TEKES, Biowaffle Project 40274/03 and MFM Project 424/31/04), the European Commission (EU Spare Parts Project QLK6-CT-2000-00487), the Academy of Finland (Project 73948) and the Ministry of Education (Graduate School of Biomaterials and Tissue Engineering) are greatly appreciated.
-
strength retention properties of self reinforced poly l lactide sr plla sutures compared with polyglyconate Maxonr and polydioxanone pds sutures an in vitro study
Biomaterials, 2002Co-Authors: Pirkka Mäkelä, Pertti Törmälä, Timo Waris, Timo Pohjonen, Nureddin AshammakhiAbstract:Abstract Recent developments in manufacturing techniques have led to the development of strong bioabsorbable materials such as self-reinforced poly l -lactide (SR-PLLA) sutures. The aim of the study was to investigate the mechanical properties of SR-PLLA sutures in comparison with polyglyconate (Maxon R ) and polydioxanone (PDS) sutures in vitro. Sutures made of SR-PLLA (0.3, 0.5 and 0.7 mm ∅), Maxon R (0.3 and 0.5 mm ∅) and PDS (0.3 and 0.5 mm ∅) were studied by immersion in phosphate-buffered distilled water (pH 7.4) at 37°C for 40 weeks. The breaking force of straight sutures and suture knots was measured. Tensile strength and percentage elongation were calculated. Means, standard deviations, differences between means, and confidence intervals for differences between means were evaluated. SR-PLLA, PDS and Maxon R sutures of 0.3 and 0.5 mm ∅ were of comparable initial tensile strength. Initial knot tensile strength values were lower than those of their counterpart straight sutures. Maxon R sutures had lost their tensile strength by 12 weeks; PDS sutures by 20 weeks. SR-PLLA sutures of 0.3 mm ∅ had a strength of 161.6 MPa and those of 0.5 mm ∅ had a strength of 134 MPa at 40 weeks. The highest percentage elongation of straight sutures (62.8% and 62%) was exhibited by PDS; the lowest by SR-PLLA (35.6% and 35%). In loop tests, PDS showed the highest percentage elongation (43.7% and 58.1%) and SR-PLLA had the lowest values (19.7% and 33%). SR-PLLA sutures had the most prolonged strength retention in vitro, but the lowest elongation (elasticity). Compared with straight sutures, knots had lower tensile strength and elongation values. SR-PLLA sutures can be applied to the closure of wounds that need prolonged support, such as bone.
-
Comparison of strength properties of poly-L/D-lactide (PLDLA) 96/4 and polyglyconate (Maxon) sutures: in vitro, in the subcutis, and in the achilles tendon of rabbits.
Journal of biomedical materials research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.
-
comparison of strength properties of poly l d lactide pldla 96 4 and polyglyconate Maxon sutures in vitro in the subcutis and in the achilles tendon of rabbits
Journal of Biomedical Materials Research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.
Pirkka Mäkelä - One of the best experts on this subject based on the ideXlab platform.
-
strength retention properties of self reinforced poly l lactide sr plla sutures compared with polyglyconate Maxonr and polydioxanone pds sutures an in vitro study
Biomaterials, 2002Co-Authors: Pirkka Mäkelä, Pertti Törmälä, Timo Waris, Timo Pohjonen, Nureddin AshammakhiAbstract:Abstract Recent developments in manufacturing techniques have led to the development of strong bioabsorbable materials such as self-reinforced poly l -lactide (SR-PLLA) sutures. The aim of the study was to investigate the mechanical properties of SR-PLLA sutures in comparison with polyglyconate (Maxon R ) and polydioxanone (PDS) sutures in vitro. Sutures made of SR-PLLA (0.3, 0.5 and 0.7 mm ∅), Maxon R (0.3 and 0.5 mm ∅) and PDS (0.3 and 0.5 mm ∅) were studied by immersion in phosphate-buffered distilled water (pH 7.4) at 37°C for 40 weeks. The breaking force of straight sutures and suture knots was measured. Tensile strength and percentage elongation were calculated. Means, standard deviations, differences between means, and confidence intervals for differences between means were evaluated. SR-PLLA, PDS and Maxon R sutures of 0.3 and 0.5 mm ∅ were of comparable initial tensile strength. Initial knot tensile strength values were lower than those of their counterpart straight sutures. Maxon R sutures had lost their tensile strength by 12 weeks; PDS sutures by 20 weeks. SR-PLLA sutures of 0.3 mm ∅ had a strength of 161.6 MPa and those of 0.5 mm ∅ had a strength of 134 MPa at 40 weeks. The highest percentage elongation of straight sutures (62.8% and 62%) was exhibited by PDS; the lowest by SR-PLLA (35.6% and 35%). In loop tests, PDS showed the highest percentage elongation (43.7% and 58.1%) and SR-PLLA had the lowest values (19.7% and 33%). SR-PLLA sutures had the most prolonged strength retention in vitro, but the lowest elongation (elasticity). Compared with straight sutures, knots had lower tensile strength and elongation values. SR-PLLA sutures can be applied to the closure of wounds that need prolonged support, such as bone.
-
Comparison of strength properties of poly-L/D-lactide (PLDLA) 96/4 and polyglyconate (Maxon) sutures: in vitro, in the subcutis, and in the achilles tendon of rabbits.
Journal of biomedical materials research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.
-
comparison of strength properties of poly l d lactide pldla 96 4 and polyglyconate Maxon sutures in vitro in the subcutis and in the achilles tendon of rabbits
Journal of Biomedical Materials Research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.
Pertti Törmälä - One of the best experts on this subject based on the ideXlab platform.
-
Histomorphometric analysis of poly-L/D-lactide 96/4 sutures in the gastrocnemius tendon of rabbits.
The International journal of artificial organs, 2006Co-Authors: Jarmo Kangas, Pertti Törmälä, Timo Waris, Ari Pajala, Juhana Leppilahti, Jorma Ryhänen, Satu Länsman, Nureddin AshammakhiAbstract:BACKGROUND Common Achilles tendon ruptures are not usually fixed by bioabsorbable sutures due to limitations in their strength retention properties. Modern technology has made it possible to develop bioabsorbable sutures with prolonged strength retention. AIMS To evaluate histologically tissue reactions of poly-L/D-lactide (PLDLA) sutures implanted in Achilles tendon of rabbits. MATERIAL AND METHODS Fifteen rabbits were evaluated at 2, 6 and 12 weeks postoperatively, with five rabbits in each follow-up group. PLDLA monofilament sutures were implanted into the medial gastrocnemius tendon. Polyglyconate monofilament sutures with similar diameter (Maxon 4-0, Cyanamid of Great Britain Ltd., Gosport, UK) were implanted in the contralateral gastrocnemius tendon. The histology was studied in hard-resin embedded samples. The thickness of the formed fibrous tissue capsule was determined histomorphometrically. RESULTS PLDLA led to formation of significantly thinner fibrous tissue capsule than Maxon sutures of the same diameter. Median thickness (PLDLA vs. Maxon) at two weeks was 5.26 vs.13.22 microm, at six weeks 11.66 vs. 80.97 microm, and at 12 weeks 10.63 vs. 17.59 microm (p
-
strength retention properties of self reinforced poly l lactide sr plla sutures compared with polyglyconate Maxonr and polydioxanone pds sutures an in vitro study
Biomaterials, 2002Co-Authors: Pirkka Mäkelä, Pertti Törmälä, Timo Waris, Timo Pohjonen, Nureddin AshammakhiAbstract:Abstract Recent developments in manufacturing techniques have led to the development of strong bioabsorbable materials such as self-reinforced poly l -lactide (SR-PLLA) sutures. The aim of the study was to investigate the mechanical properties of SR-PLLA sutures in comparison with polyglyconate (Maxon R ) and polydioxanone (PDS) sutures in vitro. Sutures made of SR-PLLA (0.3, 0.5 and 0.7 mm ∅), Maxon R (0.3 and 0.5 mm ∅) and PDS (0.3 and 0.5 mm ∅) were studied by immersion in phosphate-buffered distilled water (pH 7.4) at 37°C for 40 weeks. The breaking force of straight sutures and suture knots was measured. Tensile strength and percentage elongation were calculated. Means, standard deviations, differences between means, and confidence intervals for differences between means were evaluated. SR-PLLA, PDS and Maxon R sutures of 0.3 and 0.5 mm ∅ were of comparable initial tensile strength. Initial knot tensile strength values were lower than those of their counterpart straight sutures. Maxon R sutures had lost their tensile strength by 12 weeks; PDS sutures by 20 weeks. SR-PLLA sutures of 0.3 mm ∅ had a strength of 161.6 MPa and those of 0.5 mm ∅ had a strength of 134 MPa at 40 weeks. The highest percentage elongation of straight sutures (62.8% and 62%) was exhibited by PDS; the lowest by SR-PLLA (35.6% and 35%). In loop tests, PDS showed the highest percentage elongation (43.7% and 58.1%) and SR-PLLA had the lowest values (19.7% and 33%). SR-PLLA sutures had the most prolonged strength retention in vitro, but the lowest elongation (elasticity). Compared with straight sutures, knots had lower tensile strength and elongation values. SR-PLLA sutures can be applied to the closure of wounds that need prolonged support, such as bone.
-
Comparison of strength properties of poly-L/D-lactide (PLDLA) 96/4 and polyglyconate (Maxon) sutures: in vitro, in the subcutis, and in the achilles tendon of rabbits.
Journal of biomedical materials research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.
-
comparison of strength properties of poly l d lactide pldla 96 4 and polyglyconate Maxon sutures in vitro in the subcutis and in the achilles tendon of rabbits
Journal of Biomedical Materials Research, 2001Co-Authors: Jarmo Kangas, Senja Paasimaa, Pirkka Mäkelä, Johana Leppilahti, Pertti Törmälä, Timo Waris, Nureddin AshammakhiAbstract:Achilles tendon rupture is a common injury. Absorbable sutures are not commonly used because of their limited strength properties. Recently, sutures with prolonged strength retention properties have been developed. The aim of the study is to test the mechanical properties of recently developed poly-L/D-lactide (PLDLA) sutures in comparison with polyglyconate (Maxon) sutures. PLDLA (0.2 mm thick) and Maxon (4.0) sutures were studied in vitro by immersion in a buffered saline solution (pH 7.4). Tensile strength tests were done on sutures retrieved after 1-26 weeks. In vivo, they were implanted in the subcutis of 32 rabbits. Tensile strength tests were done on sutures retrieved after 1-6 weeks. The sutures were also used to repair the Achilles tendon in rabbits. Maximum force before breaking and percentage elongation of tendons were determined. Although PLDLA had a lower initial tensile strength than Maxon, PLDLA showed more prolonged tensile strength retention than Maxon. Tendons repaired with PLDLA, however, had a lower strength than Maxon-repaired tendons at six weeks (insignificant difference). PLDLA has more prolonged tensile strength properties compared with Maxon. Thus, PLDLA offers an alternative to Maxon in repair of the Achilles tendon.