title: Active tactile sensibility of single-tooth implants versus natural dentition: a split-mouth double-blind randomized clinical trial.
abstract: BACKGROUND
  Unlike passive sensitivity of implants/teeth that is assessed more, only three controversial studies have compared active tactile sensibility (ATS) of implants and teeth.
  
  
  OBJECTIVE
  We aimed to explore the difference between the ATS of teeth and single-tooth implants.
  
  
  METHODS
  The ATS of single-tooth implants and contralateral teeth was measured in 25 patients after they bit on gold and placebo foils 0- to 70-μm thick, each for five times, in a random order blinded to patients and assessor, carried out at two sessions. Based on the experimental range of 0 μm (mock trials) to 70 μm, the sigmoid shape of psychometric curve was estimated to locate the 50% values as the ATS thresholds for each tooth or implant. ATS Data were analyzed using paired and unpaired t-tests and multiple linear regression (α = 0.05, β ≤ 0.1). Also, equivalence testing approach was used to assess semi-objectively the clinical significance.
  
  
  RESULTS
  Average ATS values for teeth and implants were 21.4 ± 6.55 μm and 30.0 ± 7.55 μm, respectively (p = .0001 [paired t-test]). None of the geometric characteristics of implants nor duration of implant in function were correlated with the ATS (p > .4 [regression]). Age was positively associated with the ATS of both implants and teeth (p ≤ .019 [regression]). Tooth ATS (but not implant ATS) was significantly higher in males compared with females (p = .050 [unpaired t-test]), which contributed to a generalizable tooth-implant difference higher than 8-μm clinical equivalence margin in females. The ATS was not significantly different between arches or between anterior/posterior regions (p > .6).
  
  
  CONCLUSIONS
  There was a slight but statistically significant difference between implant and tooth tactile sensitivities.
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran; Center for Implant Research, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Kazemi
authors.forename: Farideh
authors.initials: F
authors.lastname: Geramipanah
authors.forename: Ramin
authors.initials: R
authors.lastname: Negahdari
authors.forename: Vahid
authors.initials: V
authors.lastname: Rakhshan
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001732:Bite Force; D019250:Dental Implants, Single-Tooth; D003776:Dental Porcelain / Q000737:chemistry; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D004311:Double-Blind Method; D005260:Female; D006047:Gold Alloys / Q000737:chemistry; D006801:Humans; D008297:Male; D008334:Mandible / Q000502:physiology; D008437:Maxilla / Q000502:physiology; D016876:Metal Ceramic Alloys / Q000737:chemistry; D008875:Middle Aged; D010919:Placebos; D011594:Psychometrics; D012684:Sensory Thresholds / Q000502:physiology; D012737:Sex Factors; D014070:Tooth / Q000502:physiology*; D014110:Touch / Q000502:physiology*; D055815:Young Adult
chemical_list: D006047:Gold Alloys; D016876:Metal Ceramic Alloys; D010919:Placebos; D003776:Dental Porcelain
keywords: active tactile sensibility; dental implants; interdental perception; osseoperception; psychometric function; surface properties