ABSTRACT
The objective of the present study was to submit specimens with amalgam restorations to 4 different polishing techniques and one control group without polishing. The specimens were then submitted to rugosimetric analysis and the differences compared.
Subject(s)
Dental Amalgam/chemistry , Dental Polishing/methods , Analysis of Variance , Carbon Compounds, Inorganic , Dental Alloys/chemistry , Dental Polishing/instrumentation , Evaluation Studies as Topic , Rubber , Silicates , Silicon Compounds , Surface Properties , Zinc OxideABSTRACT
The authors studied the superficial hardness of composite resins cured for two different times: 20 and 40 seconds of light exposure. The hardness values were read immediately and 24 hours after polymerization. A significant increase in hardness was observed with 40 s exposure as compared to 20 s. Hardness values were significantly higher at 24 h than immediately after polymerization.
Subject(s)
Bisphenol A-Glycidyl Methacrylate , Composite Resins/chemistry , Resin Cements , Hardness , Light , Materials Testing , Polymethacrylic Acids/chemistry , Polyurethanes/chemistry , Surface Properties , Time FactorsABSTRACT
Square standard cavities were prepared in human teeth and restored with amalgam obtained from alloys of different trade-marks. Twenty-four hours after condensation, excess amalgam was removed from three of the four margins, each with a different rotatory instrument (number 4 bur, multiblade finishing bur, and fine green stone). No rotatory instrument was used on the fourth margin (control), and this control was polished with pumice and zinc-oxide pastes and Sweeney's brushes. Vickers' tests for micro-hardness of the amalgam were performed on the four margins of the restorations. The restorations were then submitted to metallographic polishing, and a second micro-hardness measurement was made seven days later. The statistical analysis of the data showed that micro-hardness values were higher at the margins on which no rotatory instruments were used. The lowest micro-hardness values were found at the margins where finishing and/or round burs were used. Polishing with fine green stones gave intermediate values.
Subject(s)
Dental Amalgam/chemistry , Dental Polishing/instrumentation , Analysis of Variance , Dental Restoration, Permanent , Hardness , HumansABSTRACT
The objective of the present study was to relate changes in reflex-vegetative functions and phonetics to the etiology of temporomandibular joint dysfunction-pain syndrome. Myofunctional therapy associated with an occlusal splint had a very significant effect in relieving the pain and dysfunction caused by this type of disorder.
Subject(s)
Physical Therapy Modalities , Splints , Temporomandibular Joint Dysfunction Syndrome/therapy , Breathing Exercises , Humans , Relaxation TherapyABSTRACT
Dental cavities were prepared and restored with amalgam, using three different silver alloys. The surface of the restorations was finished 24 hours after condensation, with a rotatory instrument using a low- or high-speed handpiece. The specimens were then submitted to metallographic polishing and one of the margins of the amalgam restoration were then submitted to Vickers' micro-hardness test. Another micro-hardness test was accomplished 168 hours after condensation and the two sets of micro-hardness values were compared. No significant statistical differences were detected between the micro-hardness values obtained with low or high speed in the polishing technique.
