title: The influence of initial mucosal thickness on crestal bone change in similar macrogeometrical implants: a prospective randomized clinical trial.
abstract: OBJECTIVE
  The objective of this study was to evaluate crestal bone changes around bone- and tissue-level implants related to initial mucosal thickness.
  
  
  METHODS
  Patients received at least 2 implants: one with the prosthetic abutment connection at the crestal bone level (MC) and one with the prosthetic abutment connection at 2.5 mm supra crestal (LC). Flap thickness measurements were taken using a periodontal probe after raising the buccal flap. Patients were divided into 2 groups according to the mucosal thickness-Group A (thickness, ≤2 mm) and Group B (thickness, >2 mm).
  
  
  RESULTS
  Our study included 33 patients and 78 implants. Each patient received at least 1 implant of each type: Group A (MC), 17 implants, with a mean bone change of -0.6 ± 0.5 mm; Group B (MC), 20 with a mean bone change of -0.2 ± 0.4 mm; Group A (LC), 15 with a mean bone change of -0.1 ± 0.5 mm; and Group B (LC), 22 with a mean bone change of -0.2 ± 0.4 mm. A paired-samples t-test for groups A (MC) and B (MC) yielded a statistically significant difference (P = 0.003); there was no statistically significant difference for groups A (LC) and B (LC) (P = 0.518).
  
  
  CONCLUSIONS
  If the initial mucosal thickness surrounding bone-level implants is more than 2 mm, there is significantly less crestal bone change compared with bone-level implants placed in initial mucosal thicknesses of 2 mm or less. This difference is not statistically significant when tissue-level implants are used and the implant-abutment connection is 2.5 mm above the crestal bone level.
authors.affiliation: Department of Oral Implantology and Prosthetic Dentistry of the Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands.
authors.forename: Paul
authors.initials: P
authors.lastname: van Eekeren
authors.affiliation: Department of Oral Implantology and Prosthetic Dentistry of the Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands.
authors.forename: Pieter
authors.initials: P
authors.lastname: van Elsas
authors.affiliation: Department of Oral Implantology and Prosthetic Dentistry of the Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands.
authors.forename: Ali
authors.initials: A
authors.lastname: Tahmaseb
authors.affiliation: Department of Oral Implantology and Prosthetic Dentistry of the Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands.
authors.forename: Daniel
authors.initials: D
authors.lastname: Wismeijer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000539:Alveolar Process / Q000473:pathology*; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D005260:Female; D005881:Gingiva / Q000033:anatomy & histology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013524:Surgical Flaps
chemical_list: D015921:Dental Implants
keywords: bone implant interactions; soft tissue-implant interactions; wound healing