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Hesperidin, a bioflavonoid, is an abundant and inexpensive by-product of Citrus cultivation. A deficiency of this substance in the diet has been linked with abnormal capillary leakiness as well as pain in the extremities causing aches, weakness and night leg cramps. No signs of toxicity have been observed with the normal intake of hesperidin or related compounds. Both hesperidin and its aglycone hesperetin have been reported to possess a wide range of pharmacological properties. This paper reviews various aspects of hesperidin and its related compounds, including their occurrence, physical and chemical properties, analysis, pharmacokinetics, safety and toxicity and the marketed products available. A special emphasis has been laid on the pharmacological properties and medicinal uses of these compounds.

Chitosan, a natural polysaccharide, is being widely used as a pharmaceutical excipient. It is obtained by the partial deacetylation of chitin, the second most abundant natural polymer.Chitosan comprises a series of polymers varying in their degree of deacetylation, molecular weight, viscosity, pKa etc. The presence of a number of amino groups permit chitosan to chemically react with anionic systems, thereby resulting in alteration of physicochemical characteristics of such combinations.Chitosan has found wide applicability in conventional pharmaceutical devices as a potential formulation excipient, some of which include binding, disintegrating and tablet coating properties. The polymer has also been investigated as a potential adjuvant for swellable controlled drug delivery systems. Use of chitosan in novel drug delivery as mucoadhesive, gene and peptide drug administration via the oral route as well as its absorption enhancing effects have been explored by a number of researchers.Chitosan exhibits myriad biological actions, namely hypocholesterolemic, antimicrobial and wound healing properties. Low toxicity coupled with wide applicability makes it a promising candidate not only for the purpose of drug delivery for a host of drug moieties (antiinflammatories, peptides etc.) but also as a biologically active agent.It is the endeavour of the present review to provide an insight into the biological and pharmaceutical profile of chitosan. Various investigations carried out recently are reported, although references to research performed on chitosan prior to the recent reviews have also been included, where appropriate.

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The mucoadhesive properties of chitosan microspheres prepared by different methods were evaluated by studying the interaction between mucin and microspheres in aqueous solution. The interaction was determined by the measurement of mucin adsorbed on the microspheres. A strong interaction between chitosan microspheres and mucin was detected. The intensity of the interaction was dependent upon the method of preparation of chitosan microspheres and the amount of mucin added. The extent of mucus adsorption was proportional to the absolute values of the positive zeta potential of chitosan microspheres. The zeta potential in turn was found to be dependent upon the method of preparation of microspheres. The adsorption of type III mucin (1% sialic acid content) was interpreted using Freundlich or Langmuir adsorption isotherms. The values of r 2 were greater for Langmuir isotherm as compared with Freundlich isotherm. The adsorption of a suspension of chitosan microspheres in the rat small intestine indicated that chitosan microspheres prepared by tripolyphosphate cross-linking and emulsification ionotropic gelation can be used as an excellent mucoadhesive delivery system. The microspheres prepared by glutaraldehyde and thermal cross-linking showed good stability in HCl as compared with microspheres prepared by tripolyphosphate and emulsification ionotropic gelation.

Carbomers are extensively being used in controlled drug delivery systems (CDDS). They are also finding numerous applications in oral mucoadhesive drug delivery because of their ability to interact with the mucus glycoprotein and to remain localized to a specific site. The present review aims at giving an insight into the potential application of carbomers in mucoadhesive CDDS. This review deals with the physicochemical properties of carbomers and various mechanisms of mucoadhesion. The mechanism for the release of the drug, both water soluble and water insoluble, is discussed. The use of carbomers in oral delivery of peptides or protein-based drugs is also covered.

Dentigerous cysts are usually encountered in the practice of pediatric dentistry. The treatment modalities range from marsupialization to enucleation of the lesion and are based on the involvement of the lesion with the adjacent structures. However, loss of a permanent tooth in the management of a dentigerous cyst can be devastating to a child who has already a congenitally missing tooth. The first case describes the technique of marsupialization in which we extracted the grossly carious deciduous 1st molar and created a window through the extracted socket to decompress the lesion. In this case the 2nd premolars were congenitally missing on both sides of the mandible for which we had not gone for enucleation of the dentigerous cyst along with the developing 1st premolar. The second case is a developmental type of a big dentigerous cyst where marsupialization was followed by enucleation of the cystic lining but without removal of the affected tooth. Both the teeth erupted in the oral cavity.