title: The Conometric Concept: Definitive Fixed Lithium Disilicate Restorations Supported by Conical Abutments.
abstract: OBJECTIVE
  The use of the conical coupling connection to support definitive restorations was evaluated in cases involving full acrylic resin or hybrid acrylic resin-composite prostheses. The aim of this study was to evaluate the performance of definitive fixed partial prostheses made with lithium disilicate and supported by coupling connection abutments and healed implants.
  
  
  METHODS
  The prostheses were placed in the posterior regions of partially edentulous patients; 65 patients received fixed lithium disilicate restorations splinted with conical coupling connections to two implants. Implants were placed into healed sites and fresh extraction sockets. The prostheses were placed after healing periods of 3 months: restorations were followed yearly for 3 years. At each follow-up visit, peri-implant bone levels and pocket depths were recorded. Esthetic, functional, and biologic United States Public Health Services (USPHS) parameters modified by the FDI World Dental Federation study design were assessed at the last follow-up appointments.
  
  
  RESULTS
  Two prostheses (3.07%) fractured: one was related to framework design error; one was caused by a car accident. Three patients reported small chips: these restorations were immediately polished. No significant difference involving peri-implant bone and probing levels between the experimental times were found. None of the prostheses became loose.
  
  
  CONCLUSIONS
  The results of this research indicated that abutment-prostheses coupling connections were successful within the timeframe of this study.
authors.affiliation: Private Practice, Bologna, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Degidi
authors.affiliation: Department of Neuromotory and Biomedical Sciences (DIBINEM), University of Bologna, Italy.
authors.forename: Diego
authors.initials: D
authors.lastname: Nardi
authors.affiliation: Private Practice, Bologna, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Sighinolfi
authors.affiliation: Department of Medical, Oral, and Biotechnological Sciences, University of Chieti-Pescara, Italy.
authors.forename: Adriano
authors.initials: A
authors.lastname: Piattelli
mesh_terms: D000328:Adult; D000368:Aged; D059605:Dental Implant-Abutment Design; D003776:Dental Porcelain / Q000737:chemistry*; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D004955:Esthetics, Dental; D005260:Female; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000534:rehabilitation; D008297:Male; D008875:Middle Aged; D010512:Periodontal Index; D016896:Treatment Outcome
chemical_list: C493120:lithia disilicate; D003776:Dental Porcelain
keywords: Conometric concept; Morse cone; conical coupling; lithium disilicate