title: Buccal bone formation after flapless extraction: a randomized, controlled clinical trial comparing recombinant human bone morphogenetic protein 2/absorbable collagen carrier and collagen sponge alone.
abstract: BACKGROUND
  Flapless extraction of teeth allows for undisturbed preservation of the nearby periosteum and a source of osteoprogenitor cells. Recombinant human bone morphogenetic protein 2 (rhBMP-2) has been used for different bone augmentation purposes with great osteoinductive capacity. The aim of this study is to compare the bone regenerative ability of rhBMP-2 on an absorbable collagen sponge (ACS) carrier to a collagen sponge (CS) alone in extraction sites with ≥50% buccal dehiscence.
  
  
  METHODS
  Thirty-nine patients requiring extraction of a hopeless tooth with ≥50% buccal dehiscence were enrolled. After flapless extraction and randomization, either rhBMP-2/ACS carrier or CS alone was placed in the extraction site. After extraction, a baseline cone beam computed tomography (CBCT) scan was obtained of the site, and a similar scan was obtained 5 months postoperatively. Medical imaging and viewing software were used to compare the baseline and 5-month postoperative images of the study site and assess ridge width measurements, vertical height changes, and buccal plate regeneration.
  
  
  RESULTS
  Radiographically, CBCT analysis showed that with ≥50% of buccal bone destruction, rhBMP-2/ACS was able to regenerate a portion of the lost buccal plate, maintain theoretical ridge dimensions, and allow for implant placement 5 months after extraction. The test group performed significantly (P <0.05) better in regard to clinical buccal plate regeneration (4.75 versus 1.85 mm), clinical ridge width at 5 months (6.0 versus 4.62 mm), and radiographic ridge width at 3 mm from the alveolar crest (6.17 versus 4.48 mm) after molar exclusion. There was also significantly (P <0.05) less remaining buccal dehiscence, both clinically (6.81 versus 10.0 mm) and radiographically (3.42 versus 5.16 mm), at 5 months in the test group. Significantly (P <0.05) more implants were placed in the test group without the need for additional augmentation. The mean loss in vertical ridge height (lingual/palatal) was less in the test sites but was not significantly (P = 0.514) different between the test and control groups (0.39 versus 0.64 mm).
  
  
  CONCLUSIONS
  rhBMP-2/ACS compared to CS alone used in flapless extraction sites with a buccal dehiscence is able to regenerate lost buccal plate, maintain theoretical ridge dimensions, and allow for implant placement 5 months later.
authors.affiliation: Department of Periodontics, University of Texas Health Science Center at San Antonio Dental School, San Antonio, TX.
authors.forename: Angela M
authors.initials: AM
authors.lastname: Coomes
authors.forename: Brian L
authors.initials: BL
authors.lastname: Mealey
authors.forename: Guy
authors.initials: G
authors.lastname: Huynh-Ba
authors.forename: Concepcion
authors.initials: C
authors.lastname: Barboza-Arguello
authors.forename: William S
authors.initials: WS
authors.lastname: Moore
authors.forename: David L
authors.initials: DL
authors.lastname: Cochran
mesh_terms: D020341:Absorbable Implants; D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000601:surgery; D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000187:drug effects; D000540:Alveolar Ridge Augmentation / Q000379:methods; D055396:Bone Morphogenetic Protein 2 / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects; D002508:Cephalometry / Q000379:methods; D003094:Collagen; D054893:Cone-Beam Computed Tomography / Q000379:methods; D015921:Dental Implants; D004337:Drug Carriers; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008875:Middle Aged; D010012:Osteogenesis / Q000187:drug effects*; D011994:Recombinant Proteins / Q000627:therapeutic use; D014081:Tooth Extraction; D020390:Tooth Socket / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000601:surgery; D016212:Transforming Growth Factor beta / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D055396:Bone Morphogenetic Protein 2; D015921:Dental Implants; D004337:Drug Carriers; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; D003094:Collagen