title: Biofilm and saliva affect the biomechanical behavior of dental implants.
abstract: Friction coefficient (FC) was quantified between titanium-titanium (Ti-Ti) and titanium-zirconia (Ti-Zr), materials commonly used as abutment and implants, in the presence of a multispecies biofilm (Bf) or salivary pellicle (Pel). Furthermore, FC was used as a parameter to evaluate the biomechanical behavior of a single implant-supported restoration. Interface between Ti-Ti and Ti-Zr without Pel or Bf was used as control (Ctrl). FC was recorded using tribometer and analyzed by two-way Anova and Tukey test (p<0.05). Data were transposed to a finite element model of a dental implant-supported restoration. Models were obtained varying abutment material (Ti and Zr) and FCs recorded (Bf, Pel, and Ctrl). Maximum and shear stress were calculated for bone and equivalent von Misses for prosthetic components. Data were analyzed using two-way ANOVA (p<0.05) and percentage of contribution for each condition (material and FC) was calculated. FC significant differences were observed between Ti-Ti and Ti-Zr for Ctrl and Bf groups, with lower values for Ti-Zr (p<0.05). Within each material group, Ti-Ti differed between all treatments (p<0.05) and for Ti-Zr, only Pel showed higher values compared with Ctrl and Bf (p<0.05). FC contributed to 89.83% (p<0.05) of the stress in the screw, decreasing the stress when the FC was lower. FC resulted in an increase of 59.78% of maximum stress in cortical bone (p=0.05). It can be concluded that the shift of the FC due to the presence of Pel or Bf is able to jeopardize the biomechanical behavior of a single implant-supported restoration.
authors.affiliation: Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil. Electronic address: dimorvan_bordin@hotmail.com.
authors.forename: Dimorvan
authors.initials: D
authors.lastname: Bordin
authors.affiliation: Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil. Electronic address: dira_cavalcanti@hotmail.com.
authors.forename: Indira M G
authors.initials: IM
authors.lastname: Cavalcanti
authors.affiliation: Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil. Electronic address: marcelejardim@gmail.com.
authors.forename: Marcele
authors.initials: M
authors.lastname: Jardim Pimentel
authors.affiliation: Department of Materials Engineering, Mechanic Engineering School, University of São Paulo, São Carlos, SP, Brazil. Electronic address: cfortula@sc.usp.br.
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Fortulan
authors.affiliation: Department of Restorative Dentistry, Federal University of Juiz de Fora, Juiz de Fora, MG, Brazil. Electronic address: brunosottomaior@gmail.com.
authors.forename: Bruno S
authors.initials: BS
authors.lastname: Sotto-Maior
authors.affiliation: Department of Restorative Dentistry, Federal University of Juiz de Fora, Juiz de Fora, MG, Brazil. Electronic address: altcury@fop.unicamp.br.
authors.forename: Altair A
authors.initials: AA
authors.lastname: Del Bel Cury
authors.affiliation: Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil. Electronic address: wanderjose@fop.unicamp.br.
authors.forename: Wander José
authors.initials: WJ
authors.lastname: da Silva
mesh_terms: D018441:Biofilms; D015921:Dental Implants; D003799:Dental Stress Analysis; D020342:Finite Element Analysis; D017276:Friction; D006801:Humans; D012463:Saliva; D013314:Stress, Mechanical; D014025:Titanium; D015040:Zirconium
chemical_list: D015921:Dental Implants; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide
keywords: Bone; Finite element analysis; Friction; Titanium; Zirconium oxide