[ABVD chemotherapy scheme at day 1 and 8 for treatment of primary Hodgkin's lymphomas].

OBJECTIVE: To explore the effect of adriamycin, bleomycin, vincristine and dacarbazinum (ABVD) chemotherapy scheme executed at day 1 and day 8 for primary Hodgkin's lymphomas (HL). METHODS: 62 patients with primary HL in stages II - IV treated in our department from October 2005 to October 2006 were divided into group A and B at random with 31 patients in each group. The patients in group A received ABVD chemotherapy scheme executed at day 1 and day 8 for 6 - 8 cycles. The patients in group B received ABVD chemotherapy scheme executed at day 1 and day 15 for 6 - 8 cycles. The patients of the groups received radiotherapy by the same doctor after chemotherapy according to the patients condition and the radiotherapy regimens were not affected by the grouping. RESULTS: The complete remission rate (CR) in group A after chemotherapy was 90.3% (28/31); the one-year and two-year disease free survival (DFS) rates were 87.1% (27/31) and 80.0% (20/25) respectively. The CR rate in group B after chemotherapy was 83.9% (26/31); the one-year and two-year DFS rates were 80.6% (25/31) and 72.0% (18/25) respectively. The discrepancy of CR rates and the one-year and two-year DFS rates between the two groups was not significant (P > 0.05). The incidences of therapeutic side effects such as myocardial ischemia grade III - IV liver function impairment, pulmonary fibrosis and serious marrow inhibition between the two groups were not significant too (P > 0.05). Average chemotherapy period for the patients in group A was 159 days; it was 69 days shorter than that in group B. CONCLUSION: The CR rate, 1-year DFS rate and 2-year DFS rate of ABVD chemotherapy scheme executed at day 1 and 8 are similar to those of ABVD chemotherapy scheme executed at day 1 and 15 for primary HL in stages II - IV. The side-effects of chemotherapy between group A and B are similar too. The chemotherapy period in group A is shortened significantly.

[Effect of etching concentration on bond strength of the light-cured resin reinforced glass ionomer cement].

PURPOSE: To compare the shear strength of a light-cured resin reinforced glass ionomer cement with brackets after the enamel was etched with different etching concentrations. METHODS: sixty maxillary first premolars were randomly divided into 6 groups (A, B, C, D, E, F) with 10 teeth in each group. Then the teeth in each group were treated with different methods. All specimens were bathed with an artificial saliva after 10-minute bonding for 24 hours, then the shear strength were tested. The adhesive remain index (ARI) after bracket removal from the enamel was recorded and analyzed using SPSS11.5 software package. RESULTS: The mean shear bond strength was 14.786 MPa+/-4.940 Mpa in group A, 7.002 MPa+/-3.768 Mpa in group C, 7.879 MPa+/-3.013 Mpa in group D, 7.452 MPa+/-2.561 Mpa in group E, 7.406 MPa+/-2.407 Mpa in group F, while not tested in group B. The difference was not significant among group C, D, E and F. While the difference was significant between group A and the other groups. The difference of ARI in each group was not significant. CONCLUSIONS: The different etching concentrations in this experiment had no significant influence to the shear strength of the brackets which were boned with RMGIC. There was no significant difference of ARI among the six groups in which enamel was treated with different etching concentrations.

[Three dimensional finite element analysis of the upper incisor with different levels of periodontal support].

PURPOSE: To study the stress variation and distribution of the periodontium and the tooth initial displacement when the lingual fixate forces were applied to the depressed periodontal height. METHODS: Spiral CT (SCT) scanning technology, digital image transfer and transcription were used to obtain the initial 3-D data of the upper central incisor. The 3-D finite element models at six periodontal support heights were created by reducing the height of periodontal support tissues. RESULTS: With the loss of the alveolar height, the maximum equivalent stress and the principle stress of the upper central incisor periodontium increased. The maximum draw stress located on the lingual apex, while the maximum compressive stress located on the lingual crest of the ridge. The increment of periodontium stress was not proportional to the horizontal alveolar loss. CONCLUSIONS: With the horizontal alveolar loss, the rotation center moved toward the apex and the capacity of periodontal support decreased significantly. In orthodontic treatment, the force should be decreased in proportion to retain the physiological movement and to avoid further injury of the support tissues.

[Comparison on shear bond strength of Edgewise brackets bonding with three orthodontic adhesives against salivary contamination].

OBJECTIVE: To compare the shear bond strength and ARI score of Edgewise brackets bonding with three adhesives under moist and dry conditions after salivary contamination. METHODS: Sixty extracted human premolars were randomly and equally divided into 3 groups. Edgewise brackets were bonded directly with composite resin, super bond C&B and single component adhesive under moist and dry conditions after salivary contamination. The shear bond strength and ARI score were measured and recorded. RESULTS: The shear bond strength of Edgewise brackets bonding with composite resin and single component adhesive under moist condition after salivary contamination decreased significantly and it can't meet the requirement of orthodontic therapy (6-8 MPa) while that under dry condition can. Super bond C&B can meet the requirement of orthodontic therapy on both conditions. CONCLUSION: Super bond C&B can be used under both moist and dry conditions after salivary contamination. Composite resin and single component adhesive can only be used under dry condition after salivary contamination.