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accretions (əkrē´shənz), an older term for accumulations of foreign material such as plaque, materia alba, calculus, and other debris on teeth. Now called deposits.
References in periodicals archive ?
Scientists looked for galaxies emitting high levels of radiation and x-rays - a classic signature of black holes devouring gas and dust through accretion, or attracting matter gravitationally.
Data from two follow-up examinations over six years showed that smokers develop more calculus (rock-hard calcified accretions on tooth surfaces) but less dental plaque, the bacteriations on tooth surfaces) but less dental plaque, the bacterialaden mucous film that tooth brushing can remove.
Morris's third objection to 'pedantic reconstruction' was that the accretions collected by buildings over succeeding generations are in effect a record of history, and their destruction impoverishes the present because it suppresses the past.