Clinical effect of a guided resin cementation technique in the treatment of vertical food impaction / 口腔疾病防治

Objective@# To explore the clinical effect of a guided resin cementation technique on vertical food impaction symptoms and to provide a new method for the treatment of vertical food impaction. @* Methods @#Treatment of 76 patients with vertical food impaction with guided resin cementation was performed. A specially fabricated contact shaping wire was used to aid the shaping of the contact. Cementation was applied under a rubber dam with the total-etch technique with flowable composite resin. Patient subjective perception was recorded after treatment (i.e., “totally relieved”=3, “significantly improved”=2, “slightly improved”=1 and “no change”=0). Follow-up visits lasted for one year. Scores of 1 to 3 were recorded as effective. The efficiency rates at different times were calculated. @*Results@#Patient subjective perceptions scored 2.47, 2.21, 1.79, 1.30 and 0.97 on the day immediately after and 1, 3, 6, and 12 months after treatment, respectively. There were significant differences among scores at each time point (P<0.01). The Efficacy rate reached 91.78% immediately after treatment and was sustained above 50% within half a year. Management of resin debonding or fracture successfully relieved the symptoms again.@*Conclusion@#The guided resin cementation technique relieves vertical food impaction symptoms immediately, and the effect of the guided resin cementation technique is maintained for a short period of time. Management of resin debonding or fracture helps consolidate treatment outcomes.

PfGBP: una proteína de unión al telómero de Plasmodium falciparum / PfGBP: A Plasmodium falciparum telomere binding protein / PfGBP: uma proteína de ligação o telômero em Plasmodium falciparum

Los telómeros son estructuras complejas de ADN y proteína localizadas en el extremo de los cromosomas eucariotes. Su principal función es proteger el extremo cromosomal de ser reconocido y procesado como ADNs fracturado, evitando así eventos de recombinación y fusión que conducen a inestabilidad cromosomal. El ADN telomérico consta de secuencias cortas, repetidas una tras otra, ricas en guanina; la cadena rica en guanina se extiende formando una región de cadena sencilla denominada extremo 3' protuberante. Las proteínas por su parte, se pueden clasificar en: dsBPs, o proteínas de unión a la cadena doble, GBPs aquellas que reconocen específicamente el extremo protuberante y, proteínas que las interconectan mediante interacciones proteína-proteína. El gen PF3D7_1006800 de Plasmodium falciparum codifica para una proteína putativa similar a una GBP de Criptosporidium parvum, con el fin de establecer si esta proteína de P. falciparum presenta la capacidad de unión al ADN telomérico del parásito, se produjo una proteína recombinante a partir de la región codificante del gen, se purificó y se utilizó en ensayos de unión a ADN, y en la generación de anticuerpos policlonales específicos contra PfGBP. Nuestros resultados indican que la proteína de P. falciparum es una proteína nuclear con capacidad de unión al ADN telomérico in vitro, por lo que podría ser parte del complejo proteico encargado de proteger y/o mantener el telómero in vivo.

Telomeres are specialized structures at the end of chromosomes that consist of repetitive DNA sequences and associated proteins. The primary role of telomeres is to protect the end of linear chromosomes from recombination, fusion, and recognition as broken DNA ends. This protective function can be achieved through association with specific telomere binding proteins. Telomeric DNA consists of G-rich double-stranded arrays followed by a single-stranded G-rich overhang. The telomeric proteins can be classified in dsBPs, which bind double-stranded DNA, GBPs those that bind specifically to G-rich overhang, and proteins that interact with telomeric factors. Plasmodium falciparum gene PF3D7_1006800 codifies for a protein highly similar to Cryptosporidium parvum GBP. In order to investigate whether the P. falciparum protein binds telomeric DNA, a recombinant protein was produced, purified and DNA binding assays were performed. Polyclonal antibodies against rPfGBP were produced and tested in western blot. Our results indicate that PfGBP is a nuclear protein that binds telomeric DNA in vitro, which could be part of the protein complex responsible for protecting and/or maintaining the telomere in vivo.

Os telómeros são estruturas complexas de DNA e proteína localizadas no extremo dos cromossomas dos eucariotas. Sua principal função é proteger o extremo dos cromossomas para que não sejam reconhecidos e processados como DNAs fraturados. O anterior evita eventos de recombinação e fusão que conduzem à instabilidade nos cromossomas. O DNA telomérico tem sequencias curtas e repetidas, ricas em guanina. A cadeia rica em guanina estende-se para formar uma região de cadeia simples chamada extremo 3' protuberante. As proteínas podem-se classificar em: dsBPs ou proteínas de união à cadeia dupla, GBPs que são as que reconhecem especificamente o extremo protuberante e, as proteínas que interligam mediante interações proteína-proteína. O gene PF3D7_1006800 de Plasmodium falciparum codifica para uma proteína similar a uma GBP de Criptosporidium parvum. Com o objetivo de estabelecer se a proteína de P. falciparum presenta a capacidade de união ao DNA telomérico, foi produzida uma proteína recombinante partindo da região codificante do gene, purificou-se e utilizou-se nos ensaios de união ao DNA e na geração de anticorpos policlonais específicos contra PfGBP. Os nossos resultados indicam que a proteína de P. falciparum é uma proteína nuclear com capacidade de união ao DNA telomérico in vitro, pelo que poderia fazer parte do complexo proteico encarregado de proteger e/ou manter o telómero in vivo.

Implant Overhang after Unicompartmental Knee Arthroplasty: Oxford Prosthesis versus Miller-Galante II Prosthesis

PURPOSE: The purpose of the present study is to compare the prevalence of implant overhang between the Oxford and the Miller-Galante II (M-G II) unicompartmental knee arthroplasty (UKA) prostheses and determine whether overhang is associated with postoperative clinical results. MATERIALS AND METHODS: We retrospectively reviewed one hundred and seven UKAs which consisted of 37 Oxford UKAs and 70 M-G II. Overhang was considered present if > or =3 mm overhang was observed in any zone. The range of motion, the Knee Society scores and the Western Ontario and McMaster scores were compared after a mean follow-up duration of 48 months. RESULTS: Thirty three of 107 knees (30.8%) had overhang in at least one zone of the femoral or tibial component. In the tibial side, there were no significant differences between the groups in component overhang in each zone. In the femoral side, the Oxford UKA group showed a significantly higher prevalence of the posterior overhang of the femoral component (19/37, 51.4%) than did the M-G II UKA group (3/70, 4.3%; p<0.001). However, no significant differences in clinical results were observed between the two groups. There were also no significant differences in clinical results between the overhang and the non-overhang groups. CONCLUSIONS: Posterior overhang of the femoral component was highly prevalent in Oxford UKA patients. However, posterior overhang of the femoral component had no significant relationship with postoperative clinical results in both Oxford and M-G II UKAs at a mean of 48 months follow-up.

Can We Use the Posterior Condylar Off set as a Predictive Factor for Overhang of the Implant in Total Knee Arthroplasty?

PURPOSE: We tried to demonstrate whether the posterior condylar offset (PCO, the distance from the femoral diaphysis posterior cortex to the posterior condylar margin) and ratio (PCOR, dividing PCO by the maximum antero-posterior diameter of the distal femur) could be used as predictive factors for overhang of the implants or using gender implants in total knee arthroplasty (TKA). MATERIALS AND METHODS: One hundred and one women who underwent TKA using NexGen(R) (LPS) implants, were analyzed prospectively. After distal femoral resection, the mediolateral (ML) width was measured at four points (anterior, distal anterior, distal posterior and posterior) and compared with the ML width of the implant. The aspect ratio (AR, ML/AP ratio) and anterior/distal posterior ML width (Ant/DP) were calculated. Preoperative radiographic PCO and PCOR were measured. Differences of PCO, PCOR, AR and Ant/DP according to the size were analyzed and correlations between PCO, PCOR and AR were also analyzed. The patients were classified into two groups according to the presence of overhang, and differences of each parameter were compared between the two groups. RESULTS: The size of the implant was positively correlated PCO, not significantly correlated with PCOR, and negatively correlated with AR and Ant/DP. PCO and PCOR and AR showed no correlation with each other. PCO and PCOR were not significantly different between the two groups. However, AR and Ant/DP were statistically low in the group with overhang. CONCLUSIONS: Preoperative radiographic PCO or PCOR could not be used as a predictive factor for overhang of the implants or using gender implants in TKA.

Tibial Plateau Coverage in Total Knee Replacement Arthroplasty: Coverage on 12 quadrants / 대한정형외과학회잡지

PURPOSE: We investigated proximal tibial cutting surface in total knee replacement arthroplasty to improve its coverage and get basic data for developing more adequate tibial components for Koreans. MATERIALS AND METHODS: Of cases of total knee replacement arthroplasty performed by one surgeon between September 1995 and October 1996, we chose 100 cases with no bony defect on resected tibial surface. We traced the outline of tibial resection margin manually and then, decided the most adequate size for each tibial tray from 5 companies, AGC (Biomet, Warsaw, USA), Advantim (Wright medical technology, Arlington, USA), AMK (DePuy, Warsaw, USA), MGII (Zimmer, Indiana, USA), and Series 7000 (Osteonics, New Jersey, USA). We divided the tibial cutting surface with 12 quadrants by 30 degree radian. Then, we overlaped both images (traced tibial surface margin and tibial tray) on the computer and fixed the position when we got the largest coverage of area. From this position we calculated the coverage, underhang and overhang ratios by pixel counts. During this process, we discarded 20 cases because of inadequate overlapping. RESULTS: The overall average ratio of coverage was 82.3%, underhang 17.3%, and overhang 6.0%. The consequence of good coverage and minimal underhang were posterolateral, posteromedial, anterolateral, anteromedial and posterior aspects sequentially. But the posterior side was more overhanged by tibial component than anterior side. CONCLUSION: We feel that improving coverage on posterior and anteromedial portion is key to increasing the coverage ratio of proximal tibia in total knee replacement arthroplasty.

Tibial Plateau Coverage in total knee Replacement arthroplasty

Maximizing tibial coverage is an important consideration in total knee replacement arthroplasty to provide stability and even load transfer and to improve long term survival rate of the implants. We evaluated the coverage, underhang and overhang ratio for the proximal tibial resection surface during total knee replacement arthroplasty in Koreans. After cutting the proximal tibia, the outline of tibial resection surface was traced manually. We compared 5 tibial tray designs, AGC(Biomet, Warsaw, U.S.A.), Advantim(Wright medical technology, Arlington, U.S.A.), AMK(DePuy, Warsaw, U.S.A), MG II(Zimmer, Indiana, U.S.A.), Series 7000(Osteonics, New Jersey, U.S.A.), which have been commercially used in Korea for total knee replacement arthroplasty. The average percentage of coverage area were 83.3% in AGC, 81.6% in AMK, 80.3% in MG II, 80.2% in Advantim and 76.9% in Series 7000. The average percentage of underhang were 16.7% in AGC, 18.4% in AMK, 19.6% in MG II, 19.8% in Advantim and 23,1% in Series 7000. The average percentage of overhang were measured 7.97% in AGC, 7.86% in AMK, 8.01% in MG II, 8.77% in Advantim and 10.14% in Series 7000. So average coverage percentage of tibial cutting surface was 80.5% in Koreans. The factors which affect the optimal coverage, were the shape, dimensional interval of tibial trays and the number of practically useful tibial trays for Koreans.