title: Immediate implant placement with transmucosal healing in areas of aesthetic priority. A multicentre randomized-controlled clinical trial I. Surgical outcomes.
abstract: OBJECTIVE
  To compare the clinical outcomes of standard, cylindrical, screw-shaped to novel tapered, transmucosal (Straumann Dental implants immediately placed into extraction sockets.
  
  
  METHODS
  In this randomized-controlled clinical trial, outcomes were evaluated over a 3-year observation period. This report deals with the need for bone augmentation, healing events, implant stability and patient-centred outcomes up to 3 months only. Nine centres contributed a total of 208 immediate implant placements. All surgical and post-surgical procedures and the evaluation parameters were discussed with representatives of all centres during a calibration meeting. Following careful luxation of the designated tooth, allocation of the devices was randomly performed by a central study registrar. The allocated SLA titanium implant was installed at the bottom or in the palatal wall of the extraction socket until primary stability was reached. If the extraction socket was >or=1 mm larger than the implant, guided bone regeneration was performed simultaneously (Bio Oss and BioGide. The flaps were then sutured. During non-submerged transmucosal healing, everything was done to prevent infection. At surgery, the need for augmentation and the degree of wound closure was verified. Implant stability was assessed clinically and by means of resonance frequency analysis (RFA) at surgery and after 3 months. Wound healing was evaluated after 1, 2, 6 and 12 weeks post-operatively.
  
  
  RESULTS
  The demographic data did not show any differences between the patients receiving either standard cylindrical or tapered implants. All implants yielded uneventful healing with 15% wound dehiscences after 1 week. After 2 weeks, 93%, after 6 weeks 96%, and after 12 weeks 100% of the flaps were closed. Ninety percent of both implant designs required bone augmentation. Immediately after implantation, RFA values were 55.8 and 56.7 and at 3 months 59.4 and 61.1 for cylindrical and tapered implants, respectively. Patient-centred outcomes did not differ between the two implant designs. However, a clear preference of the surgeon's perception for the appropriateness of the novel-tapered implant was evident.
  
  
  CONCLUSIONS
  This RCT has demonstrated that tapered or standard cylindrical implants yielded clinically equivalent short-term outcomes after immediate implant placement into the extraction socket.
authors.affiliation: Eastman Dental Institute, University College London, London, UK. perio@zmk.unibe.ch
authors.forename: Niklaus P
authors.initials: NP
authors.lastname: Lang
authors.forename: Maurizio S
authors.initials: MS
authors.lastname: Tonetti
authors.forename: Jean E
authors.initials: JE
authors.lastname: Suvan
authors.forename: Jean
authors.initials: J
authors.lastname: Pierre Bernard
authors.forename: Daniele
authors.initials: D
authors.lastname: Botticelli
authors.forename: Ioannis
authors.initials: I
authors.lastname: Fourmousis
authors.forename: Marlene
authors.initials: M
authors.lastname: Hallund
authors.forename: Ronald
authors.initials: R
authors.lastname: Jung
authors.forename: Lars
authors.initials: L
authors.lastname: Laurell
authors.forename: Giovanni E
authors.initials: GE
authors.lastname: Salvi
authors.forename: David
authors.initials: D
authors.lastname: Shafer
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Weber
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000540:Alveolar Ridge Augmentation; D018786:Bone Substitutes / Q000627:therapeutic use; D003094:Collagen; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D017267:Dental Prosthesis Design; D005260:Female; D005500:Follow-Up Studies; D016557:Guided Tissue Regeneration, Periodontal; D006801:Humans; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D008903:Minerals / Q000627:therapeutic use; D016348:Osseointegration / Q000502:physiology; D013524:Surgical Flaps; D013529:Surgical Wound Dehiscence / Q000209:etiology; D020390:Tooth Socket / Q000601:surgery*; D016896:Treatment Outcome; D014945:Wound Healing / Q000502:physiology
chemical_list: C106416:Bio-Gide; C077540:Bio-Oss; D018786:Bone Substitutes; D015921:Dental Implants; D008567:Membranes, Artificial; D008903:Minerals; D003094:Collagen