Outcome of arthroscopic reduction association of the scapholunate joint.

This study evaluates the arthroscopic reduction association scapholunate technique and outcomes. A total of 18 patients with chronic scapholunate instability with mean follow-up of 36 months were reviewed. Postoperatively, the mean visual analogue score was 2.5 and the mean DASH score was 8. The grip strength was 27 kg on the operative side compared with 32 kg on the uninjured side. The mean wrist flexion was 46° and extension was 56°. Seven patients had complications. Six patients had scapholunate joint widening, one had windshield-wipering of the screws with loss of reduction, and two demonstrated progression of scapholunate advanced collapse deformity. Four patients underwent revision surgeries: two revision arthroscopic reduction association scapholunates and two proximal row carpectomies. A preoperative scapholunate gap of greater than 5 mm and the presence of scapholunate advanced collapse Grade I were both predictive of a complication or revision surgery. Patients with a scapholunate gap of greater than 5 mm or scapholunate advanced collapse had statistically higher complications rates.Level of Evidence IV.

Numerical analysis of the biomechanical behaviour of a weakened root after adhesive reconstruction and post-core rehabilitation.

OBJECTIVES: The purpose of this study was to perform a finite element analysis to determine whether adhesive reconstruction is able to restore the original biomechanical behaviour of weakened roots, in terms of fracture resistance, when compared with post/crown-restored teeth with intact roots. METHODS: A three-dimensional model of a maxillary central incisor was created. The model simulated an endodontically treated tooth restored with a glass-fibre post, a composite-resin core and a metal crown (Model 1). Based on Model 1, a new volume was created in the root cervical third that represented the area where the dentine structure was lost, resulting in a structurally damaged root (Model 2). A 100N load was applied to the palatal surface at 130° from the long axis of the tooth. After processing (Ansys(®) 10.0 - Canonsburg, PA, USA), the principal normal stress data were analyzed (S1, tensile; S3, compressive). RESULTS: The models demonstrated a similar S1 distribution concentrated in the lingual cervical region but different S1 levels (Model 1: 28.7MPa; Model 2: 35.3MPa). The S3 distribution indicated differences in behaviour between the models (Model 1: -18 to -27MPa along the buccal root surface; Model 2: -25 to -32MPa on the post buccal surface and along the buccal root wall). CONCLUSIONS: Although the stress distribution within the root walls remained below the ultimate stress limit of the root dentine, the adhesive reconstruction of the weakened roots did not recover the load resistance of structurally intact roots. CLINICAL SIGNIFICANCE: The decision of when to prosthetically rehabilitate weakened roots with cervical dentine structural tissue loss is a challenge for clinicians. A 'monoblock' adhesive reconstruction has been proposed for root reinforcement. During treatment planning, the possibility of restoring the mechanical resistance of the root must be evaluated if successful long-term results are to be achieved.

[Negative carving: clinical applications]. / Escultura negativa: aplicação clinica.

The objective of the negative carving technique is to develop properly the occlusal principles during fabrication of occlusal surfaces of temporary crowns or metalhi restorations.

The efficacy of low-dose versus conventional therapy of insulin for treatment of diabetic ketoacidosis.

The effect of low-dose intramuscular insulin therapy was compared with that of high-dose insulin therapy by intravenous and subcutaneous routes in 48 patients with diabetic ketoacidosis. A simplified protocol was devised to compare efficacy of the two methods of therapy in a randomized manner. Plasma glucose dropped to less than 250 mg/dl in the low-dose group in 6.7 +/- 0.8 h and in the high-dose group in 4.5 +/- 0.8 h (P = not significant). The amount of insulin necessary to lower plasma glucose to 250 mg/dl was 263 +/- 45 U in the high-dose group and 46 +/- 5 U in the low-dose group. Twenty five percent in the high-dose group and none in the low-dose group developed hypoglycemia. Other biochemical and clinical variables in the two groups were comparable. No treatment complications were noted in the low-dose group. Our studies suggest that low-dose intramuscular insulin therapy is simple and as effective as high-dose therapy in the treatment of diabetic ketoacidosis without the risk of hypoglycemia and with a diminished incidence of hypokalemia. Furthermore, the favorable response of these patients to low-dose insulin therapy suggests the absence of insulin resistance in diabetic ketoacidosis.

Comparison of the effectiveness of various routes of insulin injection: insulin levels and glucose response in normal subjects.

The difference in absorption of insulin and its glucose lowering-effect after the administration of crystalline insulin by the intravenous, intramuscular, and subcutaneous routes was compared in 14 lean normal subjects. Insulin in a dose of 0.1 U/kg body weight was given by the three different routes. Blood was drawn from the opposite arm at regular intervals for the determination of insulin, glucose, glucagon, cortisol, and potassium. Intravenous insulin produced the highest pharmacological level of insulin in 2 minutes (2099 +/- 414 muU/ml) with marked hypoglycemia at 30 minutes (a 68% drop). Intravenous insulin injection produced an increase in plasma glucagon and cortisol reaching a 2-fold increase above the fasting level 30 minutes after the glucose nadir. An equivalent amount of intramuscular insulin produced a maximal increase in plasma insulin at 50 minutes (45 +/- 4 muU/ml) and caused a 35% drop in plasma glucose at 60 minutes, which effects were greater than those caused by subcutaneous injection (highest IRI = 36 +/- 3.5 muU/ml and 23% glucose drop at 180 minutes). No significant increase in glucagon or cortisol was noted with equivalent amounts of subcutaneous or intramuscular insulin injection. Our studies suggest that, in normal lean subjects, insulin injection by the intramuscular route provides a faster absorption of insulin with a concomitant greater drop in plasma glucose than does injection by the subcutaneous route.