From initial case report to randomized clinical trial through 20 years of research in periodontal therapy.

Aim: Case reports (CRs) are often the first publication of a new treatment, but randomized clinical trials (RCTs) are needed to confirm the data. The aim of this study was to evaluate how many therapies published as CRs were followed by RCTs of these therapies over a 20-year period.

Material And Methods: Two researchers conducted a search through international periodontal journals and found the CRs on periodontal treatments published from 1984 to 1986.

Randomized clinical trials in implant therapy: relationships among methodological, statistical, clinical, paratextual features and number of citations.

Objectives: The aim of the present study was to investigate the relationships among reported methodological, statistical, clinical and paratextual variables of randomized clinical trials (RCTs) in implant therapy, and their influence on subsequent research.

Materials And Methods: The material consisted of the RCTs in implant therapy published through the end of the year 2000. Methodological, statistical, clinical and paratextual features of the articles were assessed and recorded.

Citation classics in periodontology: a controlled study.

Aim: The aims of this study were to identify the most cited articles in Periodontology published from January 1990 to March 2005; and to analyse the differences between citation Classics and less cited articles.

Material And Methods: The search was carried out in four international periodontal journals: Journal of Periodontology, Journal of Clinical Periodontology, International Journal of Periodontics and Restorative Dentistry and Journal of Periodontal Research. The Classics, that are articles cited at least 100 times, were identified using the Science Citation Index database.

Root curvature: differences among dental morphotypes and modifications after mechanical instrumentation.

Background: This study was designed to describe a method for measuring root curvature of extracted teeth, compare root curvature of four different dental morphotypes before mechanical instrumentation, and measure root curvature after mechanical instrumentation.

Methods: Fifty-five maxillary (14 central incisors, 13 lateral incisors, 14 cuspids, 14 premolars) extracted teeth were analyzed. Measurements were recorded on the horizontal plane at the most apical point of the cemento-enamel junction (CEJ).