• Title/Summary/Keyword: bone screw fixation

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Comparative Biomechanical Study of Stiffness on Ligamentous Attached Sites of Distal Femur - Experimental Laboratory Study on Cadaver Femora - (원위 대퇴골 인대 부착부의 강도 비교 - 사체의 대퇴골에 행한 실험적 연구 -)

  • Kwak, Ji-Hoon;Sim, Jae-Ang;Yang, Sang-Hoon;Kim, Dong-Hee;Lee, Beom-Koo
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.8 no.1
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    • pp.26-32
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    • 2009
  • Purpose: This study was performed to compare the strength of ligamentous attached sites of cadaveric distal femur and to obtain reliable biomechanical data to use in ligamentous reconstruction or augmentation. Materials and Methods: Fifteen cadaveric distal femurs were used for this study. After measuring the bone density, 5.0 mm cannulated screw (Experiment 1) or reconstructed porcine ligament (Experiment 2) was inserted into the each ligamentous attached sites of anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL) and lateral collateral ligament (LCL). In experiment 2, reconstructed porcine graft was fixed with bioabsorbable screw in ligamentous insertion sites. And we measured the maximal pullout force of each ligamentous attached sites of cadaveric distal femur. Results: Average bone mineral density was $1.205{\pm}0.137\;g/cm^2$ in experiment 1, $1.236{\pm}0.089\;g/cm^2$ in experiment 2, which showed no statistically significant differences. In experiment 1, average pull-out strength of ACL, PCL, MCL and LCL group were $519.1{\pm}111.7$ N, $638.9{\pm}144.4$ N, $169.7{\pm}56.0$ N, $225.6{\pm}61.5$ N respectively. In experiment 2, the average pull-out strength were $310.6{\pm}31.0$ N, $379.9{\pm}47.4$ N, $104.0{\pm}14.4$ N, $131.5{\pm}21.9$ N respectively. In experiment 1, there was no significant difference between ACL and PCL group and between MCL and LCL group. However, the maximal pullout strength of MCL and LCL group were significantly lower than that of ACL and PCL group (p<0.01). Experiment 2 showed the same results of experiment 1. Conclusion: Because stiffness of MCL and LCL attached sites are much lower than that of ACL and PCL attached sites, we may consider augmented fixation in ligamentous reconstructions of MCL and LCL.

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Burnt-out Metastatic Prostate Cancer

  • Shin, Dong Suk;Koo, Dong Hoe;Yoo, Suhyeon;Ju, Deok Yun;Jang, Cheol Min;Joo, Kwan Joong;Shin, Hyun Chul;Chae, Seoung Wan
    • Journal of Yeungnam Medical Science
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    • v.30 no.2
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    • pp.116-119
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    • 2013
  • A burnt-out prostate cancer tumor is a very rare clinical entity. The term 'burnt-out' refers to a primary tumor that has spontaneously and nearly completely regressed without treatment. Since metastasis of prostate cancer is usually encountered in the presence of advanced disease, distant metastasis with an undetectable primary tumor is very rare. We report herein a case of a burnt-out prostate cancer tumor that metastasized to the thoracic (T) spine and caused cord compression. A 66-year-old man visited the Emergency Department due to weakness of both legs for the past two days. His blood and urine tests were normal at the time. His spine magnetic resonance imaging (MRI) scans looked like bone metastasis that involved the T-7 vertebral body and a posterior element, and caused spinal cord compression. Other images, including from the brain MRI, neck/chest/abdomino-pelvic computed tomography (CT) scan and 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) and endoscopy, revealed no lesions that suggested malignancy. After total corpectomy T-7 and screw fixation/fusion at T5 to T10, the pathology report revealed a metastatic carcinoma that was strongly positive for prostate-specific antigen (PSA). The serum PSA value was 1.5 ng/mL. The transrectal 12-core prostate biopsy and ultrasonography showed no definitive hypoechoic lesion, but one specimen had slight (only 1%) adenocarcinoma with a Gleason score of 6 (3+3). The final diagnosis was burned-out prostate cancer with an initial normal PSA value. Although metastatic disease with an unknown primary origin was confirmed, a more aggressive approach in seeking the primary origin could provide a more specific treatment strategy and greater clinical benefit to patients.

The Safety and Efficacy of Cadaveric Allografts and Titanium Cage as a Fusion Substitutes in Pyogenic Osteomyelitis

  • Kim, Hyun-Woo;Ryu, Je-Il;Bak, Koang-Hum
    • Journal of Korean Neurosurgical Society
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    • v.50 no.4
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    • pp.348-356
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    • 2011
  • Objective : The safety and efficacy of various fusion substitutes in pyogenic osteomyelitis has not been investigated. We evaluated and compared the cadaveric allograft and titanium cages used to reconstruct, maintain alignment and achieve fusion in the management of pyogenic spinal infection. Methods : There were 33 patients with pyogenic osteomyelitis underwent fusion in this study. Fifteen of the 33 patients were operated on by fusion with allografts (cadaveric patella bones) and 18 of those were operated with titanium mesh cages filled with autologous cancellous iliac bone. After the affected disc and vertebral body resection with pus drainage, cadaveric allograft or titanium cages were inserted into the resected space. Posterior transpedicular screw fixation and rod compression in resected space, where cadaveric allograft or titanium cages were inserted, was performed to prevent the malposition in all patients except in 1 case. Recurrent infection was identified by serial erythrocyte sedimentation rate and cross reactive protein follow-up. Osseous union and recurred infection available at a minimum of 2 years following operation was identified. The amount of kyphosis correction and the subsidence were measured radiographically. Results : Spinal fusion was achieved in 29 of 33 patients. In the cadaveric allograft group, 93.3% of patient (14 of 15) showed the osseous union while 83.3% of patient (15 of 18) in the titanium cage group showed union. Subsidence was noted in 12 of the patients. Twelve patients (36.3%) showed unsettling amounts of subsidence postoperatively whereas 46.6% of patients in the cadaveric allograft group and 37.7% of patients in the titanium cage group showed similar subsidence, respectively. There were statistical difference in the fusion rate (p=0.397) and subsidence rate (p=0.276) between the two groups. There was significant statistical difference in the postoperative improvement of segmental kyphosis between the two groups (p=0.022), that is the improvement in sagittal alignment was greater in the titanium cage group than in the cadaveric allograft group. There was no case of recurred infection. Conclusion : The cadaveric allograft and titanium cages are effective and safe in restoring and maintaining sagittal plane alignment without increased incidence in infection recurrence in pyogenic osteomyelitis. The postoperative improvement of segmental kyphosis was better in the cage group.

Three Dimensional Study of Miniscrew about Installation Area and Angle (미니스크류 식립 각도 및 부위에 대한 3차원적 연구)

  • Jo, Hee-Sang;Lee, Jin-Woo
    • Journal of Dental Rehabilitation and Applied Science
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    • v.24 no.2
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    • pp.203-211
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    • 2008
  • Minimizing damage to anatomical structure is a prerequisite for skeletal anchorage system to install a miniscrew. This research has focused on evaluating the stability and safety of installation in the maxillary molar buccal area, in which most miniscrews are installed clinically and initial fixation is weak. CT (computerized tomography)images were taken for surveying the possibility of damaging to adjucent teeth in accordance with installation angle. If we install a mini-screw($1.2{\times}6.0mm$) in the maxillary molar buccal area, it would be located generally in the 5~8mm upper of CEJ and 3~5mm inner of the cortical bone surface. We has measured the space between roots And comparison has been made for gender and the space between roots in accordance with the 3 different angles of installation(30 degree, 40 degree, 60 degree) in 3 categories. Category 1 : between 1st molar and 2nd molar Category 2 : between 1st molar and 2nd premolar Category 3 : between 1st premolar and 2nd premolar The result are as follow; 1. The space for category 1 was significantly small. 2. For the installation angle, it was safer to install with steeper angle in category 1 and category 2, but not in category 3. According to these results, the installation a miniscrew in category 2, 3 is safer than in category 1. And it is safer to install with steeper angle in category 1 and category 2.

Anatomic Conformity of New Periarticular Locking Plates for Koreans: A Biomechanical Cadaveric Study (한국인에 대한 새로운 관절주위 잠김금속판의 해부학적 적합성: 사체를 이용한 연구)

  • Yoon, Yong-Cheol;Oh, Jong-Keon;Kim, Young-Woo;Kim, Hak Jun;Moon, Hong Joo;Kim, Nam-Ryeol
    • Journal of Trauma and Injury
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    • v.26 no.3
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    • pp.163-169
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    • 2013
  • Purpose: This study was conducted to confirm the anatomic conformity of the new periarticular locking plates designed by Zimmer on Korean adult bones and to identify the structures at risk during the application of these implants. Methods: The study was performed on the humerus, radius, and tibia of 10 adult cadavers(6 males and 4 females) procured from the cadaveric lab of our hospital. Anteroposterior (AP) and lateral X-rays were taken to confirm that the cadavers were free of any unusual lesions or anatomic variations. We used the 3.5-mm proximal humerus plate, 2.7-mm distal radius plate, 3.5- and 5.0-mm proximal tibia plates, and 3.5-mm distal tibia plate developed by Zimmer, Inc. (Zimmer periarticular locking plate). The longest plate from each group was used to confirm anatomical conformity. Standard approaches were used for each area, and soft tissue was retracted in order to pass the plate beneath the muscle. The position of the plate was confirmed using standard AP and lateral view X-rays. After this procedure had been completed, the region was dissected along the length of the implant to determine the conformity of the implant to bone and the penetrations of screws into the articular surface or violations of any vital structures, such as nerves, blood vessels, or tendons. Results: Excellent anatomical conformity was observed with Zimmer periarticular locking plates for Korean adults. The tibial nerve and the posterior tibial artery were found to be structures at risk when applying a distal tibial plate. Conclusion: Additional posterolateral fixation is recommended when dealing with cases of tibial plateau fracture when the fracture line extends to the posterolateral cortex. We recommend taking proper views using 10~15 degrees of internal rotation to ensure correct screw length and, thus, avoid penetration of vital structures and tendons.

A safe, stable, and convenient three-dimensional device for high Le Fort I osteotomy

  • Sugahara, Keisuke;Koyachi, Masahide;Odaka, Kento;Matsunaga, Satoru;Katakura, Akira
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.42
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    • pp.32.1-32.4
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    • 2020
  • Background: Le Fort I osteotomy is a highly effective treatment for skeletal jaw deformities and is commonly performed. High Le Fort I osteotomy is a modified surgical procedure performed for improving the depression of the cheeks by setting the osteotomy higher than the conventional Le Fort I osteotomy. Developments in three-dimensional (3D) technology have popularized the use of 3D printers in various institutions, especially in orthognathic surgeries. In this study, we report a safe and inexpensive method of performing a high Le Fort I osteotomy using a novel 3D device and piezosurgery, which prevent tooth root injury without disturbing the operation field for patients with a short midface and long tooth roots. Results: A 17-year-old woman presented with facial asymmetry, mandibular protrusion, a short midface, and long tooth roots. We planned high Le Fort I osteotomy and bilateral sagittal split ramus osteotomy. Prevention of damage to the roots of the teeth and the infraorbital nerve and accurate determination of the posterior osteotomy line were crucial for clinical success. Le Fort I osteotomy using 3D devices has been reported previously but were particularly large in size for this case. Additionally, setting the fixing screw of the device was difficult, because of the risk of damage to the roots of the teeth. Therefore, a different surgical technique, other than the conventional Le Fort I osteotomy and 3D device, was required. The left and right parts of the 3D device were fabricated separately, to prevent any interference in the surgical field. Further, the 3D device was designed to accurately cover the bone surface from the piriform aperture to the infra-zygomatic crest with two fixation points (the anterior nasal spine and the piriform aperture), which ensured stabilization of the 3D device. The device is thin and does not interfere with the surgical field. Safe and accurate surgical performance is possible using this device and piezosurgery. The roots of the teeth and the infraorbital nerve were unharmed during the surgery. Conclusions: This device is considerably smaller than conventional devices and is a simple, low-cost, and efficient method for performing accurate high Le Fort I osteotomy.

AN EXPERIMENTAL STUDY OF NEWLY DESIGNED IMPLANT WITH RBM SURFACE IN THE RABBIT TIBIA : RESONANCE FREQUENCY ANALYSIS AND REMOVAL TORQUE STUDY

  • Won Mi-Kyoung;Park Chan-Jin;Chang Kyoung-Soo;Kim Chang-Whe;Kim Yung-Soo;Isa Zakiahbt Mohd;Ariffin Yusnidar Tajul
    • The Journal of Korean Academy of Prosthodontics
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    • v.41 no.6
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    • pp.720-731
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    • 2003
  • Statement of problem. The importance of fixture design and surface treatment. Purpose. The clinical success of dental in plants is affected by many factors such like as degree of osseointegration, the effective load dispersion for the prostheses, and a lot of attempts have been made to overcome the difficulties. In this study, efforts were made to find the possibility of clinical acceptance of the dental implants of newly designed surface and resorbable blast media surcace. Materials and methods. In this study, two groups of custom-made, screw-shaped implants were prepared. The first with the consisting of Branemark clone design and the other with the new design. These implants were divided into four groups according to the kinds of surface treatment. Four implants($AVANA^{(R)}$, Osstem, Busan, Korea)of each group were installed in twenty rabbits. Group A was consisted of Branemark done implant left as machined, Group B with Branemark clone implants with RBM(Resorbable blast media) surface, Group C with newly designed implants left as machined and Group D with newly designed implants with RBM surface. One of the twenty rabbits died from inflammation and the observation was made for six weeks. Specimens from four groups were observed using scanning electron microscopy with 40, 100, 1000 magnification power and microsurface structures were measured by white-light scanning interferometry for three dimensional surface roughness measurements(Accura $2000^{(R)}$, Intek-Plus, Korea.). Removal torque was measured in 17 rabbits using digital torque gauge(MGT 12R, Mark-10 corp., NY, U.S.A.) immediately after the sacrifice and two rabbits were used for the histologic preparation(EXAKT $310^{(R)}$, Heraeus Kulzer, wehrheim, Germany) of specimens and observed under light microscope. Resonance frequency measurement($Osstell^{(R)}$) was taken with the 19 rabbits at the beginning of the implant fixation and immediately after the sacrifice. Results. Following results were taken from the experiment. 1. The surface of the RBM implants as seen with SEM had rough and irregular pattern with reticular formation compared to that of fumed specimens showing different surface topographies. 2. The newly designed implant with RBM surface had high removal torque value among four groups with no statistical significance. The average removal torque was $49.95{\pm}6.70Ncm$ in Group A, $51.15{\pm}4.40Ncm$ in Group B, $50.78{\pm}9.37Ncm$ in Group C, $51.09{\pm}4.69Ncm$ in Group D. 3. The RFA values were $70.8{\pm}4.3Hz$ in Group A, $71.8{\pm}3.1Hz$ in Group B, $70.9{\pm}2.5Hz$, $72.7{\pm}2.5Hz$ in Group D. Higher values were noted in the groups which had surface treatment compared to the untreated groups with no statistical significance. 4. The results from the histomorphometric evaluation showed a mean percentage of bone-to-implant contact of $45{\pm}0.5%$ in Group A, $55{\pm}3%$ in Group B, $49.5{\pm}0.5%$ in Group C, and $55{\pm}3%$ in Group D. Quite amount of newly formed bone were observed at the surface RBM-treated implants in bone marrow space.

Clinical and Radiographic Outcome of Shoulder Function after Unreamed Antegrade Intramedullary Nailing for Humerus Fracture: Ultrasonographic Evaluation for Rotator Cuff Integrity (비확공성 전향적 상완골 금속정 고정술후 견관절 기능에 대한 임상적 및 방사선학적 평가: 초음파를 이용한 회전근 개 추시관찰)

  • Baek, Seung-Hoon;Choi, Chang-Hyuk
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.6 no.1
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    • pp.1-9
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    • 2013
  • Purpose: The purpose is to perform objective evaluation for rotator cuff using ultrasonography and validate factors influencing cuff integrity as well as efficacy of follow-up ultrasonography after unreamed antegrade intramedullary nailing for humerus fracture. Materials and Methods: Seventeen patients with an average age of $55.7{\pm}18.6$ years underwent antegrade intramedullary nailing for humerus fracture and follow-up ultrasonography of shoulder joint. Mean follow-up period was $43.5{\pm}32.2$ months. Intraoperative evaluation for preoperative cuff tear was performed, of which four cuffs were repaired by single row repair technique. Clinical evaluation included visual analogue scale (VAS), range of motion, Korean Shoulder Scoring System (KSS) and American Shoulder and Elbow Society (ASES) score. Ultrasonographic evaluation was performed on cuff integrity and protrusion of proximal nail tip as well. Radiographic evaluation included time to union, protrusion of proximal nail tip and migration of proximal interlocking screw which could affect shoulder joint function. Results: Mean VAS at last follow-up was $1.65{\pm}1.84$ points. Range of motion showed forward flexion of $137.0{\pm}33.5^{\circ}$, external rotation of $43.5{\pm}12.7^{\circ}$ and internal rotation of $16.4{\pm}2.0^{\circ}$ while KSS score and ASES score were $79.6{\pm}20.7$ and $83.7{\pm}17.0$ points, respectively. Bone union was demonstrated in all cases and average time to union was $3.4{\pm}1.3$ months. Migration of proximal interlocking screw was shown in 6 cases (35%). On ultrasonographic evaluation, there were normal in 8 (47%), weaving in 4 (24%), partial tear in 5 cases (29%), but no complete tear. Protrusion of proximal nail tip was demonstrated in 8 cases (47%) on plain radiographs whereas in 11 cases (65%) on ultrasonography and was associated with increasing age (p=0.038). Ultrasonographic weaving and partial tear was associated with protrusion of proximal nail tip (p=006), but not with repair of preoperative tear (p>0.05). Conclusion: Because weaving and partial tear on ultrasonography originated from protrusion of proximal nail tip, careful insertion of nail and meticulous repair of cuff during operation lead to stable fixation with satisfactory recovery of shoulder function follow-up ultrasonography can be a useful tool for evaluating protrusion of nail tip and rotator cuff tear, of which diagnosis is difficult on plain X-ray after antegrade intramedullary nailing for humerus fracture.

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New Technique for the Reconstruction of Both Anteromedial & Posterolateral Bundles of ACL (전방십자인대의 전내측 다발 및 후외측 다발을 각각 재건하는 새로운 수술 수기)

  • Ha Chul-Won;Awe Soo-Ik
    • Journal of the Korean Arthroscopy Society
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    • v.6 no.2
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    • pp.195-199
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    • 2002
  • This article is to report a new technique for reconstruction of the anteromedial and posterolateral bundles of anterior cruciate ligament by separate tensioning and fixation of the each bundle. Method : Tibial and femoral tunnels were made with conventional technique of anterior cruciate ligament reconstruction. Tibial tunnel was enlarged $5\~7$ mm in anterior-posterior direction to make oval it in cross section. When preparing the Achilles tendon allograft, bone plug portion was trimmed as the conventional technique. The tendinous portion was trimmed as two separate bundles by dividing the tendinous portion longitudinally, so the graft is shaped like 'Y'. The bone plug portion of allograft was inserted into the femoral tunnel and fixed with absorbable cross pins. Two ligamentous portionss of the distal part of the grafts were tensioned separately at the external orifice. Anteromedial bundle was fastened under maximum tension with the knee flexed 90 degrees by post-tie method. The posterolateral bundle was fixed by the same technique with the knee in full extension. Then, an absorbable interference screw was inserted between the two bundles upto the upper end of the tibial tunnel, to get more initial rigidity of the reconstructed graft as well as to locate the two bundles in more anatomic position.

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A study of $Smartpeg^{TM}'s$ lifetime according to sterilization for implant stability (임플랜트 안정성을 위한 자기공명막대의 소독방법에 따른 수명에 관한 연구)

  • Won, Ho-Yeon;Cho, In-Ho;Lee, Joon-Seok
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.1
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    • pp.42-52
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    • 2008
  • Purpose: Resonance Frequency Analysis(RFA) technique can be used as an effective method in measuring the implant stability and documenting the clinical results. This technique also determines how stable the implant is before performing a prosthetic practice. Having become one the guidelines of the implant therapy whose final objective is the immediate loading, the $Osstell^{TM}$ mentor is giving a lot of information to the clinicians recently. In this communication, experiments were performed to investigate how reliable the measured ISQ values by $Osstell^{TM}$ mentor are, and to see if those are also stable even after sterilization. As five objectives: 1) How stable measured ISQ values after fixation $Smartpeg^{TM}s$ for 400 times. 2) How stable measured ISQ values after 'attach-detach'$Smartpeg^{TM}'s$ for 400 times. 3) How stable measured ISQ values after clinical sterilization methods. 4) How stable measured ISQ values after repeatedly sterilization in autoclave for 10 times. 5) What is the critical temperature which is lost the magnetism of $Smartpeg^{TM}$. Materials and Methods: Clinical sterilization methods(Autoclave sterilization, Dentistar sterilization, Ultra violet sterilization, Vacuum dry unit sterilization, Boiling water sterilization, combined $H_{2}O_{2}$ and Alcohol sterilization).$Smartpeg^{TM}s$. D3 Block bone($3{\times}9{\times}2cm$). Osstem implant(${\emptyset}4.1$-10mm).$Osstell^{TM}$ mentor. Individual experiment was used 8 number of $Smartpeg^{TM}s$ and they had measured to ISQ values of before experiment and after experiment. Results: 1. The measured ISQ values did not change after fixation $Smartpeg^{TM}s$ for 400 times. 2. There was no significant changes in the measured ISQ values of 'attach-detach $Smartpeg^{TM}s'$ for 400 times. 3. The measured ISQ values did not change after the usual clinical sterilization methods. 4. The measured ISQ values did not change after sterilization in autoclave for 10 times. 5. It was impossible to exactly measure the critical temperature which is lost the magnetism of $Smartpeg^{TM}s$. But, the results was resulted to lost its magnetism in higher temperature than $150^{\circ}C$/10 minute. Conclusion: The measured ISQ values showed insignificant differences in case of no changes in the magnetism of the $Smartpeg^{TM}s$. It seems that the $Smartpeg^{TM}s$ can be used repeatedly in every measurement if the original magnetisms of the $Smartpeg^{TM}s$ can be recognized. There seems to be no significant changes in the measured ISQ values of 'attach-detach $Smartpeg^{TM}s'$ only if the screw pitches were unimpaired. The clinical sterilization methods seems acceptable because the result was resulted to lost its magnetism in higher temperature than $150^{\circ}C$/10minute.