{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T11:50:00Z","timestamp":1774525800694,"version":"3.50.1"},"reference-count":0,"publisher":"Wiley","issue":"7","license":[{"start":{"date-parts":[[1999,7,1]],"date-time":"1999-07-01T00:00:00Z","timestamp":930787200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Journal of Periodontology"],"published-print":{"date-parts":[[1999,7]]},"abstract":"<jats:p><jats:bold>Background:<\/jats:bold> Periodontitis consists of a mixture of diseases, most of which respond favorably to traditional mechanical therapy. It is now recognized that advanced periodontitis does not always respond to conventional management with scaling, periodontal surgery, and oral hygiene measures. However, various types of antibiotics given systemically or locally improve the success rate of periodontal therapy. In short\u2010term studies, it has been shown that metronidazole, when systemically administered after debridement, resulted in treatment benefits including less need for surgical intervention.<\/jats:p><jats:p><jats:bold>Methods:<\/jats:bold> In this double\u2010blind study, we evaluated periodontal treatment involving initial non\u2010surgical treatment, systemic administration of metronidazole for 1 week, and then follow\u2010ups for scaling and root planing every 6 months, for 5 years. The study population consisted of 64 subjects (37 smokers and 27 nonsmokers), mean age 36.3 (\u00b13.0 SD) years, with severe periodontal disease. After initial scaling and root planing, patients were randomly assigned to the intervention or placebo groups: 400 mg metronidazole or a placebo administered at 8\u2010hour intervals for 1 week. The participants underwent an extensive clinical periodontal examination. Gingival crevicular fluid (GCF) was analyzed for spirochetes and granulocytes. Samples were cultured for <jats:italic>Actinobacillus actinomycetemcomitans<\/jats:italic> <jats:italic>(A.a.), Porphyromonas gingivalis (P.g.), and Prevotella intermedia (P.i.).<\/jats:italic><\/jats:p><jats:p><jats:bold>Results:<\/jats:bold> The number of patients infected with <jats:italic>A.a., P.g., P.i.<\/jats:italic>, and spirochetes decreased during the study. Most patients who harbored spirochetes at the end of the study had these microorganisms at the beginning. Smokers responded less favorably to periodontal therapy than non\u2010smokers. Non\u2010smoking patients who required only non\u2010surgical therapy in the intervention group showed statistically significant improvement in the clinical parameters after 5 years. Patients with complete healing, defined as the absence of inflamed sites \u22655 mm, after 5 years were found only in the intervention group. The patients considered healthy after 5 years were the same patients found to be healthy after 6 months.<\/jats:p><jats:p><jats:bold>Conclusions:<\/jats:bold> Decisive factors in the sustained long\u2010term improvement of patients who respond satisfactorily to treatment are probably initial scaling and root planing; a brief course of metronidazole; and regular follow\u2010up examinations at 6\u2010month intervals for oral hygiene and scaling and root planing. <jats:italic>J Periodontol 1999;70:761\u2010771.<\/jats:italic><\/jats:p>","DOI":"10.1902\/jop.1999.70.7.761","type":"journal-article","created":{"date-parts":[[2005,2,2]],"date-time":"2005-02-02T06:08:13Z","timestamp":1107324493000},"page":"761-771","source":"Crossref","is-referenced-by-count":42,"title":["Longitudinal Effect of Non\u2010Surgical Treatment and Systemic Metronidazole for 1 Week in Smokers and Non\u2010Smokers With Refractory Periodontitis: A 5\u2010Year Study"],"prefix":"10.1002","volume":"70","author":[{"given":"Birgitta","family":"S\u00f6der","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ulla","family":"Nedlich","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Li Jian","family":"Jin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[1999,7]]},"container-title":["Journal of Periodontology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/aap.onlinelibrary.wiley.com\/doi\/pdf\/10.1902\/jop.1999.70.7.761","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,19]],"date-time":"2025-10-19T12:05:54Z","timestamp":1760875554000},"score":1,"resource":{"primary":{"URL":"https:\/\/aap.onlinelibrary.wiley.com\/doi\/10.1902\/jop.1999.70.7.761"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1999,7]]},"references-count":0,"journal-issue":{"issue":"7","published-print":{"date-parts":[[1999,7]]}},"alternative-id":["10.1902\/jop.1999.70.7.761"],"URL":"https:\/\/doi.org\/10.1902\/jop.1999.70.7.761","archive":["Portico"],"relation":{},"ISSN":["0022-3492","1943-3670"],"issn-type":[{"value":"0022-3492","type":"print"},{"value":"1943-3670","type":"electronic"}],"subject":[],"published":{"date-parts":[[1999,7]]}}}