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The technique of neutral zone is useful. It is the convergence of many concepts and ideas into a feasible and functional method. The technique aims to build a denture in accordance with the underlying oral structures that are formed by muscle function. It acts as an alternative technique in case of highly atrophic ridges. With a history of denture instability, it is most successful. This paper seeks to provide information with an enclosure of a patient input study to use the technique.

In the laboratory, under choice situation, C. longitarsus preferred shells with greater shell width and shell weight. The correlation coefficient values calculated between the crab and shell parameters in the laboratory sample showed that this hermit crab selects a shell of suitable dimension for its occupation. In the multiple regression equations calculated with carapace length against the three shell variables aperture width, shell width and shell weight which are deemed to be important for hermit crabs, the regression coefficient of the variables varied much. The unsealed first principal component explained 84·9% of the total variability of the shell parameters and scaled first principal component explained 95·8% of shell parameters. The scaled first principal component was found to be a reliable estimator of shell size and the hermit crab, if given a choice, selected a shell of suitable dimension which fits its body quite closely. [ABSTRACT FROM AUTHOR]

The development of the larvae of the marine hermit crab Clihanarius clibanarius (Herbst) reared in the laboratory (salinity 34‰±1‰ and temperature 28°C ±1°C) is reported. Four zoeal stages and a glaucothoe were observed during development. Characteristics of the larval stages are described and compared with other known species of this genus. The time taken for development from hatching to glaucothoe is given. [ABSTRACT FROM AUTHOR]

The Indian Ocean (IO) extends over 30% of the global ocean area and is rimmed by 36 littoral and 11 hinterland nations sustaining about 30% of the world's population. The landlocked character of the ocean along its northern boundary and the resultant seasonally reversing wind and sea surface circulation patterns are features unique to the IO. The IO also accounts for 30% of the global coral reef cover, 40,000 km² of mangroves,some of the world's largest estuaries, and 9 large marine ecosystems. Numerous expeditions and institutional efforts in the last two centuries have contributed greatly to our knowledge of coastal and marine biodiversity within the IO. The current inventory, as seen from the Ocean Biogeographic Information System, stands at 34,989 species, but the status of knowledge is not uniform among countries. Lack of human, institutional, and technical capabilities in some IO countries is the main cause for the heterogeneous level of growth in our understanding of the biodiversity of the IO. The gaps in knowledge extend to several smaller taxa and to large parts of the shelf and deep-sea ecosystems, including seamounts. Habitat loss, uncontrolled developmental activities in the coastal zone, over extraction of resources, and coastal pollution are serious constraints on maintenance of highly diverse biota, especially in countries like those of the IO, where environmental regulations are weak.