title: Influence of the crown-implant connection on the preservation of peri-implant bone: a retrospective multifactorial analysis.
abstract: OBJECTIVE
  Control over marginal bone loss (MBL) and its progression is critical for preserving peri-implant tissue health. A moderate MBL over the first year has conventionally been associated with clinical success. However, different implants are associated with distinct amounts of MBL during their first functional year. Therefore, this study evaluated the MBL in pristine maxillary bone around implants with different types of implant-abutment connections and sought to determine the effect of other clinical factors on this tissue response.
  
  
  METHODS
  Two hundred forty-six implants were placed in 101 patients with a mean age of 54.43 years. The MBL around two different types of implants (internal versus external prosthetic connection) was evaluated at 6 and 18 months after loading. Different variables were recorded to analyze their influence on radiographic parameters using a complex samples general linear model.
  
  
  RESULTS
  At 18 months, MBL ranged from 0 to 3.56 mm; less than 1 mm was lost around 46.3% (mesial) and 40.2% (distal) of the implants, while no bone was lost around 19.5% (mesial) and 19.9% (distal). The MBL was significantly higher around external than internal connections (0.714 vs 0.516 mm/year, respectively). Age, smoking habit, and connection type were directly related to mesial and distal MBL at 6 and 18 months postloading.
  
  
  CONCLUSIONS
  Implant design is a key factor in peri-implant MBL. Age and smoking also play major roles in maintaining the stability of peri-implant bone.
authors.forename: Pablo
authors.initials: P
authors.lastname: Galindo-Moreno
authors.forename: Andrés
authors.initials: A
authors.lastname: Fernández-Jiménez
authors.forename: Francisco
authors.initials: F
authors.lastname: O'Valle
authors.forename: Alberto
authors.initials: A
authors.lastname: Monje
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Silvestre
authors.forename: Gintaras
authors.initials: G
authors.lastname: Juodzbalys
authors.forename: Elena
authors.initials: E
authors.lastname: Sánchez-Fernández
authors.forename: Andrés
authors.initials: A
authors.lastname: Catena
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging*; D003442:Crowns; D015921:Dental Implants; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016014:Linear Models; D008297:Male; D008437:Maxilla / Q000000981:diagnostic imaging* / Q000502:physiology; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D014070:Tooth / Q000502:physiology; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D015921:Dental Implants