الملخص
STATEMENT OF PROBLEMS: Conventional feldspathic porcelain is used extensively as a restorative material and it is subjected to grinding and polishing during fabrication and delivery procedures. There is still considerable controversy concerning the best methods to achieve the strongest porcelain restorations after such adjustments. PURPOSE: The objective of this study was to investigate the effects of (1) overglazing, (2) selfglazing, and (3) fine polishing on the flexural strength and fracture toughness of feldspathic dental porcelain. MATERIAL AND METHOD: Ninety porcelain disks were prepared for flexural strength test and sixty porcelain disks were fabricated for fracture toughness test. Specimens were divided into three groups for each test as follows: 1) overglazed 2) self-glazed 3) polished. The flexural strength of feldspathic porcelains was determined by ring-on-ring biaxial flexural strength test. The fracture toughness values of three experimental groups were obtained by indentation fracture toughness test. RESULTS: The flexural strength of overglazed group was significantly higher than that of selfglazed and polished group (P0.05). The fracture toughness values of overglazed and polished group were significantly higher than that of self-glazed group (P0.05). CONCLUSIONS: This results supported the use of polishing as an alternative to glazing metal ceramic restorations, as it was not detrimental in flexural strength and fracture toughness. But, under the conditions of this study, overglazing was the ideal surface finishing method of feldspathic dental porcelain.
الموضوعات
Dental Porcelain , Metal Ceramic Alloysالملخص
PURPOSE: A retrospective review of the radiographs of the proximal metatarsal osteotomy and distal soft tissue procedure for hallux valgus, evaluating the correction of the tibial sesamoid, was undertaken. We evaluated the correlation between the reduction of the tibial sesamoid and the clinical outcomes. MATERIALS AND METHODS: 17 patients (23 cases) with moderate to severe hallux valgus deformity underwent the proximal metatarsal osteotomy and distal soft tissue procedure. The preoperative and last follow-up radiographs were reviewed according to the tibial sesamoid grade classification recommended by the Research Committee of the American Orthopedic Foot and Ankle Society (AOFAS). We divided them into two groups according to the reduction of the tibial sesamoid. We anaylyzed the clinical outcomes in each group according to Mayo Clinic Forefoot Scoring System (FFSS). RESULTS: In all of the patients, the preoperative tibial sesamoid position were grade 2 or greater. At the last follow-up, 52% (n=12) were grade 1 or less (Group I) and 48% (n=11) were grade 2 or greater (Group II). In group I, the forefoot score was improved from preoperative mean value of 32.0 points to final follow-up value of 66.3 points. In group II, the forefoot score was improved from preoperative mean value of 31.7 points to final follow-up value of 65.9 points. There was no statistical significance between postoperative, average scores in group I and II (p>0.05). CONCLUSION: The position of the tibial sesamoid was corrected insufficiently in almost half of all cases. In view of clinical outcomes, there was no significant difference between the corrected group and the other group.
الموضوعات
Humans , Ankle , Classification , Congenital Abnormalities , Follow-Up Studies , Foot , Hallux Valgus , Hallux , Metatarsal Bones , Orthopedics , Osteotomy , Retrospective Studiesالملخص
PURPOSE: A retrospective review of the radiographs of the proximal metatarsal osteotomy and distal soft tissue procedure for hallux valgus, evaluating the correction of the tibial sesamoid, was undertaken. We evaluated the correlation between the reduction of the tibial sesamoid and the clinical outcomes. MATERIALS AND METHODS: 17 patients (23 cases) with moderate to severe hallux valgus deformity underwent the proximal metatarsal osteotomy and distal soft tissue procedure. The preoperative and last follow-up radiographs were reviewed according to the tibial sesamoid grade classification recommended by the Research Committee of the American Orthopedic Foot and Ankle Society (AOFAS). We divided them into two groups according to the reduction of the tibial sesamoid. We anaylyzed the clinical outcomes in each group according to Mayo Clinic Forefoot Scoring System (FFSS). RESULTS: In all of the patients, the preoperative tibial sesamoid position were grade 2 or greater. At the last follow-up, 52% (n=12) were grade 1 or less (Group I) and 48% (n=11) were grade 2 or greater (Group II). In group I, the forefoot score was improved from preoperative mean value of 32.0 points to final follow-up value of 66.3 points. In group II, the forefoot score was improved from preoperative mean value of 31.7 points to final follow-up value of 65.9 points. There was no statistical significance between postoperative, average scores in group I and II (p>0.05). CONCLUSION: The position of the tibial sesamoid was corrected insufficiently in almost half of all cases. In view of clinical outcomes, there was no significant difference between the corrected group and the other group.
الموضوعات
Humans , Ankle , Classification , Congenital Abnormalities , Follow-Up Studies , Foot , Hallux Valgus , Hallux , Metatarsal Bones , Orthopedics , Osteotomy , Retrospective Studiesالملخص
PURPOSE: We conducted this study to examine the clinical results of the proximal metatarsal wedge osteotomy using a single screw fixation and the distal soft tissue procedure in patients with moderate to severe hallux valgus deformity. MATERIALS AND METHODS: Between February 2002 and February 2004, we performed these procedures on 12 patients (15 cases). The 6 cases of all patients had mild to moderate instability in the first MTC (metatarsocuneiform) joint. We estimated the clinical outcomes, the radiological findings and complications. RESULTS: AOFAS score was improved from preoperative 41.5 points to 87.7 points lastly on average. The mean correction angle of HVA and IMA was 23.8 degrees and 6.6 degrees, respectively. The mean position of tibial sesamoid was 2.67 before surgery and 0.87 after surgery. The mean shortening of the first metatarsal bone was 3.07 mm after surgery. There was no pain and complications on the first MTC joint except the breakage of screw in one case and instability of the first MTC joint was improved postoperatively. CONCLUSION: We obtained good clinical and radiographic outcomes in our series. So, proximal metatarsal wedge osteotomy using a single screw fixation and distal soft tissue procedure seems one of the good surgical treatments for moderate hallux valgus deformity.
الموضوعات
Humans , Congenital Abnormalities , Hallux Valgus , Hallux , Joints , Metatarsal Bones , Osteotomyالملخص
PURPOSE: To review the result of fractures of distal radius treated with the T-plate fixation and to recommend guideline for treatment of fracture of distal radius. MATERIALS AND METHODS: Between January 1999 and December 2002, among the patients with fractures of distal radius underwent T-plate fixation, we retrospectively reviewed 52 cases that had a minimum follow-up of 12 months. According to the Fernandez classification of distal radius fractures, 18 cases were type I, 4 cases were type II, 22 cases were type III, 2 cases were type IV and 6 cases were type V. To assess the clinical result, we used the Demerit Point System and for the radiologic result, we used the Point system by Scheck. We Compare the result of treatment in fractures of distal radius by T-plate fixation and K-wire fixation in Type I and III. RESULTS: Excellent to good results were obtained in 38 cases (73%) in clinical result and 39 cases (75%) in radiological results. Radiologic evidence of arthritis was presented 6 cases at follow-up examination. There was no evidence of statistical difference between Type I using T-plate and K-wire fixation (p>0.05). However in type III, result in the group of T-plate fixation were better than in pinning group (p<0.05). CONCLUSION: We obtained good result for type III with T-plate but only T-plate fiaxtion for type V was not satisfactory