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Pathology of eye, especially in the case of glaucoma, requires optimal therapeutically effective concentration of the drug in the ocular tissues for prolonged period of time with decreased dosing frequency and improved patient compliance. In the present study, brimonidine tartrate (BRT) ocular inserts were designed based on hydrophilic and/or inert/zwitterionic polymer matrix to design mucoadhesive and extended release ocular inserts. Designed inserts were evaluated for their physicochemical properties such as crushing strength/hardness, friability, drug content and mucoadhesion, and erosion and in vitro drug release characteristics. The selected optimised formulations were compared with marketed preparation for in vivo ocular irritation in healthy rabbits and for in vivo pharmacodynamic efficacy on alpha-chymotrypsin-induced glaucomatous rabbits. The developed formulations showed good physicochemical properties and mucoadhesive strength, and a good correlation was seen between rate of erosion or swelling with drug release rate in case of formulations with higher proportion of polyethylene oxide (PEO). Modulation of drug release was achieved by incorporating Eudragit in PEO matrix. Addition of Eudragit resulted in shifting of drug release mechanism from erosion-controlled to diffusion-controlled mechanism. In vivo ocular irritation studies confirmed the absence of any irritation upon administration in rabbits. Intraocular pressure (IOP) measurement studies showed an improved IOP-lowering ability of ocular insert of BRT in comparison to eye drops.

Most of the welding of cast iron is repair welding. Carbon pickup and resulting cracks are the main concerns when welding CI. The casting process is never perfect, especially when dealing with large components. Instead of scrapping defective castings, they can often be repaired by welding. Naturally, the very high carbon concentration of typical CIs causes difficulties by introducing brittle martensite in the heat-affected zone of weld. It is therefore necessary to preheat to a temperature of 650 °C, followed by slow cooling after welding, to avoid cracking. The welding was carried out with manual shielded metal arc welding using ENiFe-CI filler metal. Shielded metal arc welding process using a nickel electrode was used to join a grey cast iron. The effect of pre heating on the microstructure, hardness, tensile and toughness was studied than the effect of post weld heat treatment (PWHT) on the microstructure, hardness, tensile and toughness was studied after that the same was tested on the preheated and post weld heat treated specimens. After that we concluded that which heat treatment process is suitable for cast iron weld.

How to cite this paper: Trivedi, V., Saxena, V. and Srivastav, A. (2015) AbstractThis paper deals with detailed corrosion analysis of explanted devices. The study of total 6 different types of orthopedic metallic implant was carried out after collecting the clinical report from the doctors, who performed these implantations. The clinical report covered the purpose of implantation, body part where implantation was done, and physiological reasons of removal of implant. The metallurgical investigation to study corrosion and any other mechanical damage to the implant surface during their service period was done using the Scanning Electron Micrography. SEM presented in this paper reveals the presence of in-vitro corrosion and mechanical damage as well, which are corroborating well with clinical reports.

Introduction: Conventional implants have great limitations in case of atrophic maxillary and mandibular ridges. Ultimately, patients who have severely atrophied jawbones paradoxically receive little or no treatment, as long as conventional implants are considered the device of first choice. Basal implants were developed with the goal to overcome the limitations of conventional implantology, primarily for atrophied ridges or inadequate bone with the protocol of immediate loading. However, studies regarding the rehabilitation followed by placement of screwable basal implants in atrophied ridges are limited. The purpose of the study was to conduct a prospective evaluation for the feasibility of placing strategic basal implants in clinical practice along with its merits and demerits. Materials and Methods: A prospective study was designed to evaluate the protocol of immediate functional loading using the technology of strategic basal implants ® for fixed complete arch prostheses and segmental teeth prostheses. A minimal of 10 patients selected in the age group of 20–80 years were restored with strategic basal implants irrespective of the quality and quantity of cancellous/alveolar bone following immediate functional loading protocols. Results: About 157 various designs of basal implants were placed in 10 patients, out of which four failed with the survival rate of 97.5% of basal implants. Discussion: The new concepts laid by basal implantology eliminate all drawbacks of conventional implantology and should be used as an adjunct to improve the quality of life of our patients. The concept of strategic implantology is innovative but reliable technique for patients in need of permanent rehabilitation.