There are alternative sets of postulates which yield entirely equivalent results for several important theories. In such cases the choice of a particular set of postulates may be based upon mathematical simplicity, close relationship to experiments or to the nature of the theory, or merely personal taste. While the postulate of conservation of energy is usually presented in similar form for the...

Investment is often irreversible: once installed, capital has little or no value unless used in production. This paper proposes, solves and characterizes a model of sequential irreversible investment by a firm facing uncertainty in technology, demand and price of capital. The solution can be found in closed form if simple (but not totally unrealistic) functional forms are assumed, and can be gi...

introduction: effective post-operative pain management is one of the problems following root canal treatment. nonsteroidal anti-inflammatory drugs (nsaids) are the most commonly prescribed analgesics in endodontics. the aim of this study was to evaluate the effectiveness of naproxen in controlling pain following root canal treatment in teeth with irreversible pulpitis. materials and methods: th...

introduction : achieving successful anesthesia and performing pain-free root canal treatment are important aims in dentistry. this is not always achievable and therefore, practitioners are constantly seeking newer techniques, equipments, and anesthetic solutions for this very purpose. the aim of this review is to introduce strategies to achieve profound anesthesia particularly in difficult case...

human dental pulp inflammation can progress to periapical lesion formation and conventional root canal treatment (rct) has been the traditional method for disease management. this observational study presents two cases of vital pulp therapy in mature molars diagnosed with irreversible pulpitis and associated with apical periodontitis. in these two clinical cases, the involved teeth had deep car...

i ntroduction: deep and long-lasting anesthesia is essential throughout endodontic treatment. this study was conducted to compare the effect of adding fentanyl to epinephrine-containing lidocaine on depth and duration of local anesthesia in painful maxillary molars with irreversible pulpitis (irp). methods and materials: this randomized double-blind, clinical trial with parallel design was cond...