Analysis of two methods for occlusal contact registration with the T-Scan system

summary Various authors have studied the reprodcibility of occlusal contact by means of the T-Scan computerized system and obtained contradictory results. In the present work the valve of the T-Scan system as a method for exploring occlusion has been analysed. For this purpose, the same variable, i.e. the number of contacts, was recorded in 31 subjects using the two operation modes enabled by the T-Scan and the respective results were then compared. After an analysis of variance was performed to test the equality of averages of the number of tooth contacts for each patient in the four positions studied (maximum intercuspation, edge to edge protrusion, right laterality and left laterality) in the time and force analysis modes, the results obtained showed that the number of occlusal contacts is significantly different for each patient both in the various mandibular positions and in the force and time analysis modes, being proportionally greater in the latter case.     

Presence of antibodies to replication protein A in some patients with systemic lupus erythematosus (SLE)

Presence of antibodies directed against replication protein A (RPA), a DNA binding protein complex composed of three subunits (RPA-70, RPA-32 and RPA-14) was investigated among patients with SLE and other autoimmune diseases using immunoblot analysis to RPA-70 and RPA-32 recombinant proteins. Anti-RPA antibodies were found in two out of 108 sera from SLE patients, one of them showing reactivity against RPA-32 and RPA-70 and the other reacting only against RPA-32. Sera from 108 patients with other autoimmune disorders as well as from 42 healthy control individuals were negative. Thus, the frequency of these antibodies in SLE is estimated to be 2–3%. The study demonstrates that RPA is one target more of the wide array of autoantigens that elicit an immune response in SLE. The presence of anti-RPA autoantibodies seems to be circumscribed to a small number of patients with SLE.     

PIGMENTED VILLONODULAR SYNOVITIS OF THE KNEE IN A PATIENT WITH PAGET'S DISEASE OF THE ADJACENT FEMORAL BONE

A 49-year-old male patient, diagnosed as having Paget's diseaseinvolving the lumbar vertebrae and both femora, felt persistentpain and swelling in the left knee after trauma. A synovectomywas performed. Clinical and histological findings led to thediagnosis of pigmented villonodular synovitis of the knee joint.Only one previous case of this association has been reported.A common aetiology for both diseases is discussed, and traumaticfactors should be considered in the aetiology of the association. KEY WORDS: Osteitis deformans, Synovitis, Paget's disease of bone, Pigmented villonodular synovitis     

Ventricular Tachycardia/Ventricular Fibrillation Ablation in the Setting of Ischemic Heart Disease

Recurrent ventricular tachycardia (VT) in the setting of coronary artery disease is frequently a life-threatening electrophysiologic emergency. Even in patients with an implantable defibrillator, recurrent VT is frequently accompanied by repeated and disabling shock therapy. Catheter ablative therapy offers the ability to provide immediate control of recurrent VT. Long-term elimination of VT should be anticipated in most patients. This article reviews the strategies, tools, techniques, and expected outcome for catheter ablation of stable and unstable ventricular arrhythmias in the setting ischemic heart disease.     

Effect of natural gel product on bovine dentin erosion in vitro

Objective

To evaluate the efficacy of Neem (Azadirachta indica) experimental gel for the prevention of erosive wear on bovine dentin, in vitro.

Material and Methods

One hundred dentin blocks were allocated into 5 experimental groups (20 samples each): C (control group, without gel); CG (control group, only base gel); F (fluoride gel, 1.23% NaF; pH 4.1, Dentsply; Brazil); N (Neem gel, 10% neem extract; pH 4.1, manipulation); NF (Neem+fluoride gel, 10% Neem extract and 1.23% NaF; pH 4.1, manipulation). The blocks were stored in artificial saliva for 24 hours. After this, they were submitted to six alternating re- and demineralization cycles. The blocks were analyzed for wear (profilometry). The results were submitted to statistical analysis by ANOVA and Tukey tests (P<0.05).

Results

The mean wear (±SD, µm) was shown as follows in groups: C (13.09±0.99), CG (10.60±1.99), F (10.90±1.44), N (12.68±1.13) and NF (10.84±1.65). All gels showed some preventive action when compared with control group. However, significant differences were found only between Neem+fluoride gel and fluoride gel.

Conclusion

A single application of a neem-containing fluoride gel reduced dentin erosion, thus it is a possible alternative in reducing dental wear. Further research should investigate the action mechanism and the synergism between them.     

Influence of bismuth oxide concentration on the pH level and biocompatibility of white Portland cement

Objectives

To investigate if there is a relation between the increase of bismuth oxide and the decrease of pH levels and an intensification of toxicity in the Portland cement.

Material and Methods

White Portland cement (WPC) was mixed with 0, 15, 20, 30 and 50% bismuth oxide, in weight. For the pH level test, polyethylene tubes were filled with the cements and immersed in Milli-Q water for 15, 30 and 60 days. After each period, the increase of the pH level was assessed. For the biocompatibility, two polyethylene tubes filled with the cements were implanted in ninety albino rats (n=6). The analysis of the intensity of the inflammatory infiltrate was performed after 15, 30 and 60 days. The statistical analysis was performed using the Kruskal-Wallis, Dunn and Friedman tests for the pH level and the Kruskal-Wallis and Dunn tests for the biological analysis (p<0.05).

Results

The results showed an increase of the pH level after 15 days, followed by a slight increase after 30 days and a decrease after 60 days. There were no significant statistical differences among the groups (p>0.05). For the inflammatory infiltrates, no significant statistical differences were found among the groups in each period (p>0.05). The 15% WPC showed a significant decrease of the inflammatory infiltrate from 15 to 30 and 60 days (p<0.05).

Conclusions

The addition of bismuth oxide into Portland cement did not affect the pH level and the biological response. The concentration of 15% of bismuth oxide resulted in significant reduction in inflammatory response in comparison with the other concentrations evaluated.