Results: Three hundred fifty-one SMs were detected in 288 patients, constituting 0.33% of the study subjects, with a greater frequency in females (56.4%). In one region associated pathologies and treatments were also evaluated. Study Design: A retrospective analysis was carried out on an initial sample of 104,902 subjects drawn from the ortopantographics files from 10 clinics in 7 Turkish cities with documentation of demographic data, the presence of SM teeth, their location, eruption, morphology, and position within the arch. Objective: The aim of the present study was to evaluate the demographic profile of supernumerary molar (SM) teeth in people in various regions of Turkey. "Molar-tooth carbonates: shallow subtidal facies of the mid- to late Proterozoic". ^ Government of Canada, Natural Resources Canada ()."The role of microbial iron reduction in the formation of Proterozoic molar tooth structures". Kunzmann, Marcus Poirier, André Halverson, Galen P. "Molar-tooth structure in Proterozoic carbonate rocks: Origin from synsedimentary earthquakes, and implications for the nature and evolution of basins and marine sediment". "Molar tooth structures of the Neoarchean Monteville Formation, Transvaal Supergroup, South Africa. "Molar tooth carbonates and benthic methane fluxes in Proterozoic oceans". ^ a b Shen, Bing Dong, Lin Xiao, Shuhai Lang, Xianguo Huang, Kangjun Peng, Yongbo Zhou, Chuanming Ke, Shan Liu, Pengju ().
#Molar teeth crack
"Gas bubble and expansion crack origin of "molar-tooth" calcite structures in the middle Proterozoic Belt Supergroup, western Montana". I: Constraints on microcrystalline CaCO3 precipitation". Iron-reducing bacteria: the reduction of Fe(III) minerals, particularly clays, to Fe(II) minerals by iron reducing bacteria may have been associated with a reduction in mineral volume (creating cracks in the sediment) and an increase in local alkalinity within the sediment (resulting in calcite precipitating in those cracks).Tsunamis: it has been suggested that seismic events resulted in the compaction of clay-rich carbonate sediments, where calcite mud was expelled and recrystallised to form molar tooth structures.Subsequent 'pumping' of seawater that was highly supersaturated with respect to calcite through these cracks resulted in the precipitation of calcite. Wave-induced fluid flow: cyclic-loading and unloading of the upper sediment column by waves traveling overhead caused movement and contraction of the sediment, forming cracks.The formation and coalescence of these gases within the upper sediment column formed the void spaces where calcite subsequently precipitated as a result of locally increased alkalinity. Gas escape: noting the similarity in shape and size of molar tooth structures to gas escape structures, it has been proposed that the formation and escape of a gas, potentially carbon dioxide or methane, during the degradation of organic matter.Mechanisms of formation Ī range of mechanisms have been proposed for the formation of molar tooth structures. Global distribution of molar tooth structures. Finally, fragments of molar tooth structures are observed as 'rip up clasts' in storm deposits, further supporting an early formation. This is further supported by deformation or fracturing of the molar tooth structures during deformation. These structures are known to have formed during very early diagenesis while the host sediment was unlithified (i.e., still soft sediment) because bedding is deformed around molar tooth structures, indicating they formed prior to compaction of the sediment. The depositional environments that molar tooth structures are found in span from deep waters near storm wave base, to shallow intertidal. The sediment matrix that molar tooth structures occur in is generally composed of finely crystalline calcite and dolomite, and fine-grained detrital quartz, feldspar, and clay minerals. The ribbons can be oriented both vertically and horizontally. Molar tooth structures are millimeter- to centimeter-scale microcrystalline ribbons and 'blobs' of calcite within argillaceous carbonate sedimentary rocks, sometimes reaching tens of centimeters in size. Note deformation of the overlying beige bed, showing deflection around the molar tooth structure. Molar tooth structures in the Neoproterozoic Båtsfjord Formation, Norway.
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