title: Effects of Collagen Resorbable Membrane Placement After the Surgical Extraction of Impacted Lower Third Molars.
abstract: OBJECTIVE
  The use of resorbable collagen membranes (RMs) in the treatment of intraosseous defects and deep periodontal pockets on the distal side of a lower second molar (L2M) after surgical extraction of an impacted lower third molar (L3M) has shown contradictory results. This study evaluated the effects of RM placement on the healing of a bone defect distal to an L2M after surgical extraction of a horizontal or mesioangular impacted L3M.
  
  
  METHODS
  A parallel-group randomized controlled trial with 2 independent groups of 30 patients requiring surgical extraction of an L3M was carried out. After extraction, patients received an RM (Bio-Gide, Geistlich Pharma AG, Wolhusen, Switzerland) or only suture. At the initial checkup and during postoperative monitoring at 1, 3, and 6 months, the distal vestibular, distal, and distolingual probing depths and distal vestibular attachment level of the L2M were measured.
  
  
  RESULTS
  Age (control group, 33.8 ± 6.9 yr; guided tissue regeneration group, 35.6 ± 6.3 yr; P = .322) and the number of women (control group, 15 of 29; guided tissue regeneration group, 14 of 27; P = .992) were similar in the 2 groups. The distal vestibular, distal, and distolingual probing depths of the L2M, distal vestibular attachment level, distance from the cementoenamel junction, and distance from the alveolar crest to the base of the defect showed greater improvement 6 months after surgical extraction in the RM group (P < .05).
  
  
  CONCLUSIONS
  The use of RMs after surgical extraction of mesioangular or horizontally impacted L3Ms stimulates bone regeneration, improving the attachment level and bone fill distal to the L2M. Likewise, it decreases the distal probing depth and results in faster recovery. RM placement after surgical extraction of an impacted L3M is recommended because it prevents periodontal defects after L3M surgery.
authors.affiliation: Director of the Department of Oral Surgery, Hospital Casa Salud, Valencia, Spain. Electronic address: dr.cortell@cimiv.es.
authors.forename: Isidoro
authors.initials: I
authors.lastname: Cortell-Ballester
authors.affiliation: Professor, Master Degree Program in Oral Surgery and Implantology; Associate Professor, Department of Oral Surgery; Faculty of Dentistry, University of Barcelona, Barcelona; Researcher, Institut d'Investigació Biomèdica de Bellvitge, Barcelona, Spain.
authors.forename: Rui
authors.initials: R
authors.lastname: Figueiredo
authors.affiliation: Director, Master Degree Program in Oral Surgery and Implantology; Professor, Department of Oral Surgery; Faculty of Dentistry, University of Barcelona; Researcher, Institut d'Investigació Biomèdica de Bellvitge, Barcelona, Spain.
authors.forename: Eduard
authors.initials: E
authors.lastname: Valmaseda-Castellón
authors.affiliation: Chairman and Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Barcelona; Coordinating Investigator, Institut d'Investigació Biomèdica de Bellvitge; Head, Department of Oral and Maxillofacial Surgery, Teknon Medical Center, Barcelona, Spain.
authors.forename: Cosme
authors.initials: C
authors.lastname: Gay-Escoda
mesh_terms: D000328:Adult; D001672:Biocompatible Materials; D003094:Collagen / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008964:Molar, Third / Q000601:surgery*; D014081:Tooth Extraction; D014095:Tooth, Impacted / Q000601:surgery*
chemical_list: D001672:Biocompatible Materials; D003094:Collagen