title: What is the effect of soft tissue thickness on crestal bone loss around dental implants? A systematic review.
abstract: OBJECTIVE
  The aim of this systematic review was to determine whether soft tissue biotype at implant placement has an influence on crestal bone loss (CBL) at 1 year after implant loading.
  
  
  METHODS
  Following electronic search in three databases (MEDLINE via OVID, EMBASE and The Cochrane Database) and hand search up to April 2015, two reviewers screened independently and in duplicate the references to identify randomized controlled trials, controlled clinical trials (CCTs) and prospective case series eligible for systematic review and meta-analysis. Cochrane Collaboration's tool was used for assessing risk of bias.
  
  
  RESULTS
  From 2944 citations, six studies (6 CCTs) met the inclusion criteria. Four of six individual studies that compared thin vs. thick biotype showed significantly higher CBL in thin biotype. Meta-analysis could only be performed with two studies and the differences did not reach significant level. None of the included studies was of low risk of bias.
  
  
  CONCLUSIONS
  At present, there is insufficient evidence to answer the question on the differences in clinical outcome in terms of CBL between implants placed in sites with initial soft tissue thickness <2 mm and those with ≥2 mm. Further, well-designed controlled clinical studies are needed to analyze the effect of soft tissue thickness on the clinical outcomes of dental implants.
authors.affiliation: Clinical Oral Research Centre, Institute of Dentistry, Barts & The London School of Medicine and Dentistry, Queen Mary University London (QMUL), London, UK.
authors.forename: Aliye
authors.initials: A
authors.lastname: Akcalı
authors.affiliation: Clinical Oral Research Centre, Institute of Dentistry, Barts & The London School of Medicine and Dentistry, Queen Mary University London (QMUL), London, UK.
authors.forename: Anna
authors.initials: A
authors.lastname: Trullenque-Eriksson
authors.affiliation: Department of Periodontology, Faculty of Dentistry, Suzhou Health College, Suzhou, China.
authors.forename: Chuanming
authors.initials: C
authors.lastname: Sun
authors.affiliation: Biostatistics Unit, UCL Eastman Dental Institute, London, UK.
authors.forename: Aviva
authors.initials: A
authors.lastname: Petrie
authors.affiliation: Clinical Oral Research Centre, Institute of Dentistry, Barts & The London School of Medicine and Dentistry, Queen Mary University London (QMUL), London, UK.
authors.forename: Luigi
authors.initials: L
authors.lastname: Nibali
authors.affiliation: Clinical Oral Research Centre, Institute of Dentistry, Barts & The London School of Medicine and Dentistry, Queen Mary University London (QMUL), London, UK.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Donos
mesh_terms: D016301:Alveolar Bone Loss / Q000209:etiology*; D015921:Dental Implants; D006801:Humans; D010486:Periapical Tissue / Q000033:anatomy & histology*; D011183:Postoperative Complications / Q000209:etiology*
chemical_list: D015921:Dental Implants
keywords: Alveolar bone loss; biotype; dental implant; soft tissue thickness