To understand the palaeoenvironmental changes during the Middle to Late Holocene period, we have carried out multiproxy analysis integrating ichnology, geochemistry, and sedimentology in the Great Rann of Kachchh (GRK). The exposed cliff sections of Rann sediments and overlying Bet sediments are explored and analysed for the characteristics of the sedimentary sequences and ichnological assemblages. Seven recurring ichnotaxa are documented, which comprise of Arenicolites, Paleophycus, Planolites, Psilonichnus, Skolithos, Teichichnus, and Thalassinoides. The ichnological and sedimentological findings were supported by obtained geochemical results, which were then compared with the existing chronological data. The trace fossils associated with the bottom of the Bet Zone and the top surface of the Great Rann sediment units (Middle Holocene) suggest the shallow marine depositional environment. Further, the monospecific occurrence of Teichichnus in the middle units (Middle to Late Holocene period) of the Bet Zone sediments suggests the brackish water environmental conditions associated with the high discharge of fluvial system leading to lowering of salinity. The topmost unit of the Bet Zone sediments shows the disappearance of trace fossils suggesting a terrestrial depositional condition. The present work suggests that the area of the western GRK has witnessed a gradual shifting of shallow marine to the fluvial environment during the Middle to Late Holocene period.

The aim of this in vitro study was to evaluate and compare the dentinal tubule occlusion using nano-hydroxyapatite (n-HAP) containing toothpaste and mouthwash under a scanning electron microscope. The specimens were randomly divided into two groups with five specimens each: group 1—toothpaste group and group 2—mouthwash group. The percentage of the occluded dentinal tubules was assessed at the baseline, 7th, 14th, 21st, and 28th days under a scanning electron microscope. The toothpaste group showed a higher percentage of occluded dentinal tubules as compared to the mouthwash group at the 7th, 14th, 21st, and 28th days, respectively. It can be concluded that brushing twice daily with n-HAP containing toothpaste for duration of 28 days produced good dentinal tubule occlusion.

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