The purpose of this study was to evaluate shear, tensile and shear/tensile combined bond strengths(SBS, TBS, S/TBS) in various orthodontic brackets bonded to human teeth with chemically cured adhesive (Ortho-one, Bisco, USA). Five types of metal brackets with various bracket base configurations (Micro-Loc base(Tomy, Japan), Chessboard base(Daesung, Korea), Non-etched Foil Mesh base(Dentarum, Germany), Micro-Etched foil Mesh base(Ortho Organiners, USA). Integral base(Unitek, USA)) were used in this study. Shear, tensile and shear/tensile combined bond strengths according to the direction of force were measured by universal testing machine. The bracket base surface after bond strength test were examined by stereoscope and scanning electron microscope. The assessment of remnant on bracket base surface was carried out by ARI(adhesive remnant index). The results obtained were summarized as follows ; 1. In all brackets, SBS was in the greatest value(p<0.05), TBS was in 50% level and S/TBS was in 30% level of SBS. 2. In bond strength, Micro-Loc base bracket showed the maximum bond strength(SBS:22.68+/-1.37kgf, TBS:11.37+/-0.42kgf, S/TBS:6.69+/-0.34kgf) and Integral base bracket showed the minimum bond strength(SBS:10.52+/-1.27kgf, TBS:4.27+/-1.08kgf, S/TBS:2.29+/-0.58kgf) (p<0.05). 3. In bond strength per unit area Integral base bracket showed the minimum value, Micro-Loc base and Chessboard base brackets were in similar value(p>0.05). Non-Etched Foil Mesh base and Micro-Etched Foil Mesh base bracket were similar in SBS and TBS(p>0.05), But Micro-Etched Foil Mesh base bracket was greater than Non-Etched Foil Mesh base bracket in S/TBS(p<0.05). 4. Bond failure sites were mainly between bracket base and adhesive, therefore ARI scores were low.
Adhesives ; Humans ; Orthodontic Brackets ; Tooth

OBJECTIVE: This study was designed to evaluate clinical features of 20 patients with rhupus syndrome and compare its characteristics with systemic lupus erythematosus(SLE) and rheumatoid artiritis(RA). METHODS: Patients considered to have rhupus who met the American College of Rheumatology(ACR) 1997 and 1987 revised criteria for SLE and RA, respectively and age, sex, and disease duration matched 64 patients with RA and 56 patients with SLE were selected for comparison. RESULTS: Twenty patients were all female and their mean age was 43.7+/-9.6 years(range 25~68). They had 5.5 ACR criteria for RA and 5 criteria for SLE. The mean age at onset of RA was 35.2+/-10.5 years(19~63) and that of SLE was 38.2+/-10.0 years(20~63), giving a mean interval between the diagnoses of the two diseases of 3.0+/-5.7 years (14~(-6)). There were 2 patients(10%) with rheumatoid nodule, and 18 patients(90%) with rheumatoid factor, and 16 patients(80%) with bone erosions on hand or wrist joints. The criterial for SLE included malar rash(20%), discoid rash(0%), photosensitivity(30%), oral ulcer(45%), arthritis(100%), serositis(35%), renal disorder(15%), neurologic disorder(0%), hematologic disorder(100%), immunologic disorder(90%), and positive antinuclear antibody(100%). Anti-dsDNA was more than 7.0U/ml in 15 patients(75%). The patients with rhupus syndrome showed lower amount of 24 hour urine protein, more severe radiologic involvement, younger age at onset of arthritis, higher titer of rheumatoid factor, lower frequency of low C3, and less complicated clinical course when compared with the patients with SLE(p<0.05). More frequent anemia, Rayanud's phenomenon, and more complicated clinical course in rhupus when compared with the patientw with RA(p<0.05), but the radiologic stage of hand and wrist was similar between rhupus and RA. CONCLUSION: Rupus syndrome showed somethisg different clinical characteristics and clinical course when compared with SLE and RA.
Anemia ; Arthritis ; Arthritis, Rheumatoid* ; Diagnosis ; Female ; Hand ; Humans ; Lupus Erythematosus, Systemic* ; Rheumatoid Factor ; Rheumatoid Nodule ; Wrist ; Wrist Joint