• Restorative Dentistry and Endodontics
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• v.21 no.1
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• pp.35-53
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• 1996

The development and repair requires the formation of new tissues comprised of various extracellular matrix components. The present study investigated the formation and distribution of the major ECM components such as type I collagen, type III collagen, fibronection, bone sialoprotein, and osteonection during development and repair. For developing observation. Sprague-Dawley rats weighing $27{\pm}1gm$ were sacrificed. For repair observation, Sprague-Dawley rats weighing $110{\pm}5gm$ were used. The pulp perforation were prepared on mesial surface of the maxillary first molar by using 1/2round bur. At 5 days after perforation, rats were sacrificed by perfusion with 3 % paroformaldehyde. The maxillary first molar region were cut, demineralized, dehydrated and embedded in paraffin. Immunostaining the ECM components was achieved by the avidin-biotin complex method. The results as follows : 1. Bright immunoreaction for fibronectin was present in the basement membrane at the inner epithelial-mesenchymal interface, especially concentrated in the blood vessel walls, cell membrane of odontoblasts, and initial predentin. 2. Type I and III collagen was observed in the newly formed pulp tissue, predentin, and its intensity increased as more of these components during repair. 3. Strong immunostaining for bone sialoprotein and osteonectin was found in dentin while no or weaker staining was observed loose connective tissue of the pulp. 4. These results suggest that develpment and repair is achieved through a series of cell differentiation and attachment by the specific ECM components.

• Clinics in Shoulder and Elbow
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• v.7 no.1
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• pp.30-34
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• 2004

Purpose: To report our experience of treatment of rotator cuff tear and evaluate the mid-term outcome. Materials and Methods: We have performed 50 cases of mini-open rotator cuff repair from March 1996 to March 1999. Male to female ratio was 34：16, the average age 46.5(23∼57) years old, mean follow-up period was 78(62∼93) months. All-arthroscopic repair and open repair cases were excluded. Mean symptomatic period was 12.5(6∼38) months, operation was indicated in cases of no improvement by 6 months of conservative management. Preoperative simple radiographs and Magnetic resonance arthrography were obtained in all cases. We also observed the inflammation, synovitis, thickness of tear and associated pathology intraoperatively. We evaluated pain, function, and range of motion by UCLA score. Results: Overall UCLA score was mean 29.5 points. Excellent 25, good 18, poor 7 cases. Mean pain score was improved 2.6 to 7.5, 44 cases(88%) were improved and 6 cases(12%) were not improved. Mean functional score was improved 3.4 to 8.5, and activity at follow up, 25 cases(50%) were same, 8 cases(14%) were above, 17 cases(34%) were below compared with preoperative level. Mean active forward flexion was preoperative 112° to postoperative 160°, forward flexion strength was improved 3.8 to 4.7. 43 cases(86%) of patients were satisfied at the result, 7 cases(14%) were not satisfied or aggravated. Results: Mini-open rotator cuff repair was effective method in treating rotator cuff tear.

• The Journal of Advanced Prosthodontics
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• v.5 no.3
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• pp.248-255
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• 2013

PURPOSE. This study compared the effect of three intraoral repair systems on the bond strength between composite resin and zirconia core. MATERIALS AND METHODS. Thirty zirconia specimens were divided into three groups according to the repair method: Group I-CoJet$^{TM}$ Repair System (3M ESPE) [chairside silica coating with $30{\mu}m$ $SiO_2$ + silanization + adhesive]; Group II-Ceramic Repair System (Ivoclar Vivadent) [etching with 37% phosphoric acid + Zirconia primer + adhesive]; Group III-Signum Zirconia Bond (Heraus) [Signum Zirconia Bond I + Signum Zirconia Bond II]. Composite resin was polymerized on each conditioned specimen. The shear bond strength was tested using a universal testing machine, and fracture sites were examined with FE-SEM. Surface morphology and wettability after surface treatments were examined additionally. The data of bond strengths were statistically analyzed with one-way ANOVA and Tamhane post hoc test (${\alpha}$=.05). RESULTS. Increased surface roughness and the highest wettability value were observed in the CoJet sand treated specimens. The specimens treated with 37% phosphoric acid and Signum Zirconia Bond I did not show any improvement of surface irregularity, and the lowest wettability value were found in 37% phosphoric acid treated specimens. There was no significant difference in the bond strengths between Group I ($7.80{\pm}0.76$ MPa) and III ($8.98{\pm}1.39$ MPa). Group II ($3.21{\pm}0.78$ MPa) showed a significant difference from other groups (P<.05). CONCLUSION. The use of Intraoral silica coating system and the application of Signum Zirconia Bond are effective for increasing the bond strength of composite resin to zirconia.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.1
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• pp.3-11
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• 2018

Objectives: The unilateral cleft lip (UCL) repair technique has evolved extensively over the past century into its modern form and has been identified as an important determinant of treatment outcome. The aim of this study was to evaluate and compare treatment outcomes following repair of UCL using either the Tennison-Randall (triangular) technique or the Millard rotation-advancement technique. Materials and Methods: This was a prospective randomized controlled study conducted at the Lagos University Teaching Hospital between January 2013 and July 2014. A total of 48 subjects with UCL presenting for primary surgery and who satisfied the inclusion criteria were recruited for the study. The subjects were randomly allocated into two surgical groups through balloting. Group A underwent cleft repair with the Tennison-Randall technique, while group B underwent cleft repair with the Millard rotation-advancement technique. Surgical outcome was assessed quantitatively according to anthropometric measurements, using a method described by Cutting and Dayan (2003). Results: Our 48 enrolled subjects were evenly divided into the two surgery groups (n=24 for both group A and group B). Twenty-seven subjects were male (56.3%) and 21 were female (43.8%), making a sex ratio of 1.3:1. The Millard group showed a greater increase in postoperative horizontal length and vertical lip height and a greater reduction in nasal width and total nasal width. Meanwhile, the Tennison-Randall group showed better reduction of Cupid's-bow width and better philtral height. Conclusion: We did not find any significant differences in the surgical outcomes from the two techniques. The expertise of the surgeon and individual patient preferences are the main factors to consider when selecting the technique for unilateral cleft repair.

• Journal of Korean Foot and Ankle Society
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• v.5 no.1
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• pp.5-12
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• 2001

Purpose: To find out the priority of which procedure has had a better outcome both clinically and radiographically between the two groups, one is treated by primary repair and the other by modified Brostr$\ddot{o}$m's procedure, by comparing the postoperative ankle joint stability and the patient's degree of satisfaction. Material and methods: 16 cases were taken into consideration whose number of severed ligaments were at least two or more of the lateral collateral ligaments of the ankle, and also were confirmed intraoperatively. Among them, 8 cases were treated with primary repair and the other 8 cases were treated with primary repair and the other 8 cases by modified Brostr$\ddot{o}$m's procedure. Results: There was no distinguishable difference for the patient's degree of satisfaction between the two procedures above mentioned. In 3 cases treated with primary repair, functional instability was observed. In case of postoperative ankle joint stability, 7 of 8 cases treated by modified Brostr$\ddot{o}$m's procedure has revealed increased joint stability. And 3 of 8 cases which were treated by primary repair have showed postoperative residual instability. Conclusion: Actually, the severed ligament can not maintain its normal strength though several months has elapsed, and possible residual instability could be remained. Therefore, it can be expected that modified Brostr$\ddot{o}$m's procedure also would be a .good method in obtaining suitable ankle joint stability as well as subtalar joint stability because of its reinforcement using extensor retinaculum.

• Journal of Korean Neurosurgical Society
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• v.60 no.4
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• pp.417-423
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• 2017

Objective : Repair of sensorial nerve defect is an important issue on peripheric nerve surgery. The aim of the present study was to determine the effects of sensory-motor nerve bridging on the denervated dermatomal area, in rats with sensory nerve defects, using a neural cell adhesion molecule (NCAM). Methods : We compared the efficacy of end-to-side (ETS) coaptation of the tibial nerve for sural nerve defect repair, in 32 Sprague-Dawley rats. Rats were assigned to 1 of 4 groups : group A was the sham operated group, group B rats had sural nerves sectioned and buried in neighboring muscles, group C experienced nerve sectioning and end-to-end (ETE) anastomosis, and group D had sural nerves sectioned and ETS anastomosis was performed using atibial nerve bridge. Neurological evaluation included the skin pinch test and histological evaluation was performed by assessing NCAM expression in nerve terminals. Results : Rats in the denervated group yielded negative results for the skin pinch tests, while animals in the surgical intervention groups (group C and D) demonstrated positive results. As predicted, there were no positively stained skin specimens in the denervated group (group B); however, the surgery groups demonstrated significant staining. NCAM expression was also significantly higher in the surgery groups. However, the mean NCAM values were not significantly different between group C and group D. Conclusion : Previous research indicates that ETE nerve repair is the gold standard for peripheral nerve defect repair. However, ETS repair is an effective alternative method in cases of sensorial nerve defect when ETE repair is not possible.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.234-241
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• 2021

By recognizing the importance of demand forecasting, the military is conducting many studies to improve the prediction accuracy for repair parts. Demand forecasting for repair parts is becoming a very important factor in budgeting and equipment availability. On the other hand, the demand for intermittent repair parts that have not constant sizes and intervals with the time series model currently used in the military is difficult to predict. This paper proposes a method to improve the prediction accuracy for intermittent repair parts of the Patriot. The authors collected intermittent repair parts data by classifying the demand types of 701 repair parts from 2013 to 2019. The temperature and operating time identified as external factors that can affect the failure were selected as input variables. The prediction accuracy was measured using both time series models and data mining models. As a result, the prediction accuracy of the data mining models was higher than that of the time series models, and the multilayer perceptron model showed the best performance.

• Journal of Korean Institute of Industrial Engineers
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• v.11 no.2
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• pp.1-9
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• 1985

In this study, two stage transfer line with limited repair capability is modeled to formulate optimal dynamic repair priority policy. The method of Markov Chains is used to analyze the analytical model of this line. An efficient algorithm is developed, utilizing the block tridiagonal structure of the transition probability matrix, to obtain the steady state probabilities and system performance measures, such as the steady state production rate of the line and the average in-process inventory in the interstage buffer.

• Journal of Korean Society for Quality Management
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• v.15 no.1
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• pp.13-19
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• 1987

This paper discusses the methods of determining optimal warranty period for repairable goods. The demand of the product is assumed to increase with the length of the warranty period. Good-as-new repair and minimal repair models are considered. The method of obtaining optimal warranty period is explored when the failure distribution is an exponential or a Weibull. The case of discounting all associated costs continuously over time is also considered.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.11 no.17
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• pp.81-85
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• 1988

This paper presents a model that considers combinations of rework, repair, replacement and scrapping. Policy-Iteration method of inspection is proposed for a serial manufacturing system whose repair cost, scrap cost and inspection cost. when it fails, can be formulated by Markovian approach. Policy-Iteration stops when new inspection policy is the same as previous inspection policy. A numerial example is presented.