title: Inter- and intra-observer agreement on Miller's classification of gingival tissue recessions.
abstract: Miller's is the most commonly used classification of gingival tissue recessions, defined as the displacement of the soft tissue margin apical to the cemento-enamel junction. However, data on the reliability of this classification are missing so far, although reliability, which reflects the consistency of repeated measurements, is regarded as a prerequisite for judging the utility of a classification. The aim of the present study was to evaluate inter- and intra-observer agreement on Miller's classification of gingival tissue recessions. Two hundred photographs (50 of each region: maxillary/mandibular anterior/posterior teeth) of gingival tissue recessions were evaluated twice by four observers with different degrees of experience in Miller's classification, gingival phenotype, tooth shape, and identifiability of the cemento-enamel junction. The following inter- and intra-observer agreements were found: Miller's classification, 0.72 and 0.73-0.95; gingival phenotype, 0.29 and 0.45-0.58; tooth shape, 0.39 and 0.44-0.59; and identifiability of the cemento-enamel junction, 0.21 and 0.30-0.59. A higher agreement was detected for anterior teeth. Further, gingival phenotype (thin-high scalloping) significantly correlated with tooth shape (long-narrow) (ρ = 0.662, p < 0.001). Miller's classification of gingival tissue recessions was evaluated by four examiners using 200 clinical photographs and yielded substantial to almost perfect agreement, with higher agreement for anterior teeth. Although limited to photographic assessment, the present study offers the so far missing proof on the sufficient inter- and intra-observer agreement of this classification.
authors.affiliation: Division of Oral Surgery, Bernhard Gottlieb School of Dentistry, Medical University of Vienna, Sensengasse 2a, 1090, Vienna, Austria. kristina.bertl@meduniwien.ac.at.|Department of Periodontology, Faculty of Odontology, Malmö University, Malmö, Sweden. kristina.bertl@meduniwien.ac.at.
authors.forename: Kristina
authors.initials: K
authors.lastname: Bertl
authors.affiliation: Division of Oral Surgery, Bernhard Gottlieb School of Dentistry, Medical University of Vienna, Sensengasse 2a, 1090, Vienna, Austria.
authors.forename: Dorothea
authors.initials: D
authors.lastname: Ruckenbauer
authors.affiliation: Academy of Oral Implantology, Vienna, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Müller-Kern
authors.affiliation: Division of Conservative Dentistry and Periodontology, Bernhard Gottlieb School of Dentistry, Medical University of Vienna, Vienna, Austria.
authors.forename: Gerlinde
authors.initials: G
authors.lastname: Durstberger
authors.affiliation: Karl Donath Laboratory for Hard Tissue and Biomaterial Research, Division of Oral Surgery, Medical University of Vienna, Vienna, Austria.|Austrian Cluster for Tissue Regeneration, Vienna, Austria.
authors.forename: Stefan
authors.initials: S
authors.lastname: Lettner
authors.affiliation: Division of Conservative Dentistry and Periodontology, Bernhard Gottlieb School of Dentistry, Medical University of Vienna, Vienna, Austria.
authors.forename: Corinna
authors.initials: C
authors.lastname: Bruckmann
authors.affiliation: Division of Oral Surgery, Bernhard Gottlieb School of Dentistry, Medical University of Vienna, Sensengasse 2a, 1090, Vienna, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Ulm
mesh_terms: D005260:Female; D005889:Gingival Recession / Q000145:classification*; D006801:Humans; D008297:Male; D015588:Observer Variation; D010641:Phenotype; D010781:Photography; D015203:Reproducibility of Results; D014070:Tooth / Q000033:anatomy & histology
keywords: Diagnosis; Gingival thickness; Gingival tissue recession; Plastic periodontal surgery; Treatment planning