{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,3]],"date-time":"2026-05-03T01:22:54Z","timestamp":1777771374410,"version":"3.51.4"},"reference-count":0,"publisher":"S. Karger AG","license":[{"start":{"date-parts":[[2009,11,18]],"date-time":"2009-11-18T00:00:00Z","timestamp":1258502400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2009,11,18]],"date-time":"2009-11-18T00:00:00Z","timestamp":1258502400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Caries Res"],"abstract":"<jats:p>Inorganic pyrophosphatase activity was quantitated in hard and soft dentine from sound and carious human teeth. The activity was measured from samples of dentine drilled from four to six different areas of 1 tooth. In intact fully formed tooth the highest rate of hydrolysis of Na&lt;sub&gt;4&lt;\/sub&gt;P&lt;sub&gt;2&lt;\/sub&gt;O&lt;sub&gt;7&lt;\/sub&gt; was found in coronal and apical circumpulpal dentine. The highest PPiase activity in hard dentine (8.23 \u03bcmol\/min and mg protein \u00d7 10\u2013\u20137) was observed in coronal circumpulpal dentine of tooth with caries reaching the dentine. In amalgam-restored tooth the values were nearly the same as in intact fully formed tooth. In tooth with caries advanced into the pulp cavity, the pigmented hard dentine gave significantly higher values (6.62 \u03bcmol) when compared with the same area of intact tooth (3.90 \u03bcmol). In more superficial areas with soft and infected carious dentine the activity was four times higher (27.61 \u03bcmol) than in pigmented dentine. The results suggest that the activity of PP&lt;sub&gt;i&lt;\/sub&gt;ase in hard circumpulpal dentine reflects the increased metabolic activity during tooth development and during the advance of caries in dentine. In soft carious dentine, the high PP&lt;sub&gt;i&lt;\/sub&gt;ase activity was thought to be caused by bacteria invading the injured tissue.<\/jats:p>","DOI":"10.1159\/000260774","type":"journal-article","created":{"date-parts":[[2009,11,18]],"date-time":"2009-11-18T06:08:16Z","timestamp":1258524496000},"page":"258-264","source":"Crossref","is-referenced-by-count":2,"title":["Quantitative Changes of Inorganic Pyrophosphatase Activities in Various States of Human Teeth"],"prefix":"10.1159","author":[{"given":"I.","family":"L\u00e4ikk\u00f6","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"127","published-online":{"date-parts":[[2009,11,18]]},"container-title":["Caries Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000260774","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T16:49:28Z","timestamp":1777481368000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000260774"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,11,18]]},"references-count":0,"URL":"https:\/\/doi.org\/10.1159\/000260774","archive":["Portico"],"relation":{},"ISSN":["0008-6568","1421-976X"],"issn-type":[{"value":"0008-6568","type":"print"},{"value":"1421-976X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,11,18]]}}}