title: Clinical and quantitative marginal analysis of feldspathic ceramic inlays at 4 years.
abstract: The aim of this clinical study was to evaluate feldspathic ceramic inlays both by clinical criteria and quantitative margin analysis in continuation of an earlier, identically conducted 2-year study. Fifty feldspathic ceramic inlays were adhesively luted in Class II preparations with all margins located in enamel. The inlays were evaluated clinically according to modified USPHS criteria after 3 and 4 years. Quantitative margin analysis was performed with a scanning electron microscope (SEM). Clinically, the inlays showed no recurrent caries and no changes in colour, but superficial marginal discolouration (6%) was apparent after 4 years. Margins were perceptible clinically in 64% of the cases after 4 years. Quantitative margin analysis showed significantly more marginal gaps at the composite/ceramic interface than at the enamel/composite interface, There was neither a significant decrease in perfect margins nor a significant increase in marginal gaps and marginal imperfections at both interfaces between the third and fourth year. Clinically, the inlays performed very well up to 4 years. Clinical evaluation using an explorer only detected substance loss in the cementation gap. The SEM evaluation showed significantly higher changes in marginal qualities during the first 2-year interval of clinical service compared to the second 2-year interval following an exponential mathematical regularity. Quantitative margin analysis should be included in clinical long-term trials to detect early marginal deficiencies at the luting interfaces.
authors.affiliation: Department of Operative Dentistry and Periodontology, University Clinics, Regensburg, Germany. karl-heinz.friedl@klinik.uni-regensburg.de
authors.forename: K H
authors.initials: KH
authors.lastname: Friedl
authors.forename: K A
authors.initials: KA
authors.lastname: Hiller
authors.forename: G
authors.initials: G
authors.lastname: Schmalz
authors.forename: B
authors.initials: B
authors.lastname: Bey
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D003743:Dental Enamel / Q000648:ultrastructure; D018772:Dental Marginal Adaptation; D019232:Dental Restoration Failure; D005069:Evaluation Studies as Topic; D006801:Humans; D007284:Inlays; D008855:Microscopy, Electron, Scanning; D017680:Potassium Compounds / Q000737:chemistry; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013997:Time Factors
chemical_list: D000538:Aluminum Silicates; D003188:Composite Resins; D017680:Potassium Compounds; C016447:feldspar