title: Smoking Modulates Gene Expression of Type I Collagen, Bone Sialoprotein, and Osteocalcin in Human Alveolar Bone.
abstract: OBJECTIVE
  Previous animal studies have shown the negative impact of smoking on bone-to-implant contact, and in humans, a decrease in bone density and implant survival over time. However, the effect of smoking on the human alveolar bone regarding the expression of bone-related markers is unknown. Therefore, the aim of this study was to evaluate the influence of smoking on the gene expression of molecules of bone metabolism in alveolar bone tissue from sites designed to receive dental implants.
  
  
  METHODS
  Biopsy specimens of alveolar bone were collected from smokers (n = 19) and nonsmokers (n = 19) from areas planned to receive dental implants. Gene expression of tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β, osteoprotegerin (OPG), type I collagen (COL-I), bone sialoprotein (BSP), and osteocalcin (OCN) was quantified by quantitative real-time polymerase chain reaction using glyceraldehyde-3-phosphate dehydrogenase as a reference gene. The results were assessed using multiple regression analysis, with a significance level of 5%.
  
  
  RESULTS
  Multiple regression analysis indicated that smoking negatively affected mRNA expression of BSP and OCN and positively altered the expression of COL-I (P < .05) despite age, gender, and arch. Moreover, regression analysis did not show a significant correlation between smoking habit and mRNA levels of TNF-α, TGF-β, and OPG (P > .05).
  
  
  CONCLUSIONS
  These results support the hypothesis that some bone markers in alveolar tissue are modulated by smoking, which could explain the negative impact of smoking on bone healing.
authors.affiliation: MSc Student, Division of Maxillofacial Surgery, Paulista University, São Paulo, Brazil.
authors.forename: Juliana Medeiros de
authors.initials: JM
authors.lastname: Campos
authors.affiliation: Professor, Division of Maxillofacial Surgery, Paulista University, São Paulo, Brazil.
authors.forename: Alexandre Javaroni
authors.initials: AJ
authors.lastname: Prati
authors.affiliation: Professor, Division of Periodontics, Paulista University, São Paulo, Brazil.
authors.forename: Fabiano Ribeiro
authors.initials: FR
authors.lastname: Cirano
authors.affiliation: Professor, Division of Periodontics, Paulista University, São Paulo, Brazil.
authors.forename: Suzana Peres
authors.initials: SP
authors.lastname: Pimentel
authors.affiliation: Professor, Division of Maxillofacial Surgery, Paulista University, São Paulo, Brazil.
authors.forename: Gabriel Pires
authors.initials: GP
authors.lastname: Pastore
authors.affiliation: Professor, Division of Statistics, Paulista University, São Paulo, Brazil.
authors.forename: Vanessa Gallego
authors.initials: VG
authors.lastname: Pecorari
authors.affiliation: Professor, Division of Periodontics, Paulista University, São Paulo, Brazil.
authors.forename: Fernanda Vieira
authors.initials: FV
authors.lastname: Ribeiro
authors.affiliation: Professor, Division of Periodontics, Paulista University, São Paulo, Brazil.
authors.forename: Marcio Zaffalon
authors.initials: MZ
authors.lastname: Casati
authors.affiliation: Professor, Division of Periodontics, Paulista University, São Paulo, Brazil. Electronic address: casarinrcv@yahoo.com.br.
authors.forename: Renato Corrêa Viana
authors.initials: RC
authors.lastname: Casarin
mesh_terms: D000539:Alveolar Process / Q000378:metabolism*; D016022:Case-Control Studies; D024042:Collagen Type I / Q000235:genetics*; D018592:Cross-Over Studies; D015870:Gene Expression; D006801:Humans; D058574:Integrin-Binding Sialoprotein / Q000235:genetics*; D015675:Osteocalcin / Q000235:genetics*; D012907:Smoking / Q000235:genetics*
chemical_list: D024042:Collagen Type I; D058574:Integrin-Binding Sialoprotein; D015675:Osteocalcin