The purpose of this study was to determine whether a 4-week isotonic resistance training program using Theraband elastic tubing and lightweight dumbbells would significantly increase concentric shoulder rotator strength or velocity of serve or both in a group of elite-level tennis players. Twenty-two male and female varsity college tennis players were randomly assigned to control or 4-week training groups. Subjects were pre- and posttested in concentric internal and external rotation torque using an isokinetic dynamometer. Functional performance was assessed before and after training by recording the peak and average velocities of eight maximal serves. The experimental group exhibited significant gains in internal rotation torque at both slow (120 deg/sec) and fast speeds (300 deg/sec) for total work and in peak torque to body weight ratio and torque acceleration energy at the fast speed. This group also exhibited significant gains in external rotation torque for the same parameters at fast speed. Regarding speed to serve, the experimental group exhibited significantly greater increase in peak speed (+6.0% compared with -1.8%) and average speed (+7.9% compared with -2.3%) compared with the control group. Men exhibited greater internal and external rotation torque on all parameters and in peak and mean speed of serve on both evaluations. Men also exhibited greater imbalance in external to internal rotation torque ratios. In conclusion, resistance training using Theraband tubing and lightweight dumbbells may have beneficial effects on strength and functional performance in college-level tennis players.
Anterior, partially edentulous residual ridges often have hard-tissue and soft-tissue defects that create esthetic and functional problems when conventional fixed prostheses are used to replace the missing teeth. However, tissue-tinted porcelain can be used in conjunction with fixed prostheses to solve many of these problems. Proper prosthesis design and shade matching are important considerations in the fabrication of fixed prostheses that incorporate tissue-tinted porcelain to restore hard-tissue and soft-tissue defects.
The nickel-chromium alloys offer promise as substitutes for gold alloys in casting crown and bridge prostheses. However, more definitive research is needed on the casting accuracy, finishing characteristics, porcelain-to-alloy bonding, and corrosion sensitivities of these materials (Moffa, J.P., and Jenkins, W.A., JADA 89:652, 1974).The requirements for accuracy and fit of nonprecious restorations have been controversial subjects. The spruing, burnout temperature, casting temperature, and casting technique used with nonprecious alloys are significantly different from those of precious alloys. Critical evaluation of the special investments commonly employed with the use of high fusing alloys for crown and bridge techniques is not complete. Further investigation of the casting accuracy of non-precious alloys is required to identify the most appropriate and least expensive alloy that will satisfy all of the clinical requirements.An experiment was designed to test the casting accuracy of four nickel-chromium alloys: Ultratek,* Omega, § Microbond N/p2,t and Nobil-Ceramt compared to a precious alloy, Jelenko ." ¶ A chromium-cobalt replica of an actual maxillary right central incisor preparation was used as a test model to simulate laboratory and clinical use of the non-precious alloys. The test model was an idealized porcelain/alloy tooth preparation of 0.3 to 0.6 mm in width involving the entire circumference of the tooth.Ten wax patterns were waxed in a uniform manner for each of the test specimens on the model. The patterns were sprued, invested, and cast according to the manufacturers' instructions. After casting, all macroscopic and microscopic bubbles and irregularities were removed with a #2 round carbide bur. The copings were then seated on the die using a constant loading force of 2.286
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.