title: Comparison of prevalence of microorganisms on titanium and silicone/polymethyl methacrylate obturators used for rehabilitation of maxillary defects.
abstract: BACKGROUND
  Silicone or polymethyl methacrylate obturators, used for rehabilitation of maxillary defects, bear the risk of an enhanced settlement of microorganisms and, therefore, impose the risk of local or systemic infections. Titanium-based obturators offer favorable characteristics in contrast to polymer-based protheses in terms of microbial biofilm formation.
  
  
  OBJECTIVE
  The purpose of this study was to compare the prevalence of microorganisms on titanium and silicone/PMMA (polymethyl methacrylate) obturators used for rehabilitation of maxillary defects.
  
  
  METHODS
  The obturators of 36 patients (17 titanium based, 19 polymer based) who underwent maxillectomy due to malignancy were evaluated. Microbiological specimens from obturator surfaces, the adjacent mucous surfaces, and the interior of polymer-based obturators were obtained with a sterile swab. Microbiological analysis was performed using conventional methods, including microscopy and culture, on several agar media. For statistical data analysis, Fisher's exact test (FT) (alpha=.05) and odds ratio (OR) (95% confidence interval) were used.
  
  
  RESULTS
  Polymer-based obturators showed a significantly higher quantitative and qualitative presence of nonphysiological microorganisms compared to titanium obturators. There is a significant risk (factor 1.4) for the penetration of bacteria to the depths of polymer-based obturators, especially if the surface is contaminated by pathological bacteria (P=.02).
  
  
  CONCLUSIONS
  The use of titanium-based obturators for the oral rehabilitation of postmaxillectomy patients significantly reduces the risk of infections with pathogenic oral microorganisms and, therefore, may protect patients from local oral or systemic infections.
authors.affiliation: Department of Cranio- and Maxillofacial Surgery, Heinrich-Heine-University, Duesseldorf, Germany. depprich@med.uni-duesseldorf.de
authors.forename: Rita A
authors.initials: RA
authors.lastname: Depprich
authors.forename: Jorg G
authors.initials: JG
authors.lastname: Handschel
authors.forename: Ulrich
authors.initials: U
authors.lastname: Meyer
authors.forename: Guido
authors.initials: G
authors.lastname: Meissner
mesh_terms: D001419:Bacteria / Q000145:classification / Q000302:isolation & purification*; D001431:Bacteriological Techniques; D018441:Biofilms / Q000254:growth & development; D002176:Candida albicans / Q000302:isolation & purification; D015169:Colony Count, Microbial; D003430:Cross-Sectional Studies; D003764:Dental Materials / Q000737:chemistry; D017267:Dental Prosthesis Design; D005260:Female; D006092:Gram-Negative Facultatively Anaerobic Rods / Q000302:isolation & purification; D006095:Gram-Positive Cocci / Q000302:isolation & purification; D016987:Gram-Positive Rods / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008441:Maxillary Neoplasms / Q000534:rehabilitation; D008875:Middle Aged; D009061:Mouth Mucosa / Q000382:microbiology; D010158:Palatal Obturators / Q000382:microbiology*; D019904:Polymethyl Methacrylate / Q000737:chemistry; D012828:Silicones / Q000737:chemistry; D014025:Titanium / Q000737:chemistry
chemical_list: D003764:Dental Materials; D012828:Silicones; D019904:Polymethyl Methacrylate; D014025:Titanium