title: The impact of frenulum height on strains in maxillary denture bases.
abstract: OBJECTIVE
  The midline fracture of maxillary complete dentures is a frequently encountered complication. The purpose of this study was to assess the effect of frenulum height on midline strains of maxillary complete dentures.
  
  
  METHODS
  A removable maxillary complete denture was fabricated and duplicated seven times. Four different labial frenulum heights were tested for stresses occurring on the palatal cameo surface. The strains were measured with strain gauges placed on 5 different locations and the stresses were calculated. To mimic occlusal forces bilaterally 100 N of load was applied from the premolar and molar region.
  
  
  RESULTS
  A statistically significant association between the height of the labial frenulum and the calculated stresses and strains was shown (P<.05) predominantly on the midline and especially on the incisive papilla. The results showed that stress on the anterior midline of the maxillary complete denture increases with a higher labial frenulum.
  
  
  CONCLUSIONS
  Within the limitations of this in vitro study, it can be concluded that the stress on the anterior midline of the maxillary complete denture increases with a higher labial frenulum. Surgical or mechanical precautions should be taken to prevent short-term failure of maxillary complete dentures due to stress concentration and low cycle fatigue tendency at the labial frenulum region.
authors.affiliation: Istanbul University, Faculty of Dentistry, Department of Prosthodontics, Istanbul, Turkey.
authors.forename: Altug
authors.initials: A
authors.lastname: Cilingir
authors.affiliation: Istanbul University, Faculty of Dentistry, Department of Prosthodontics, Istanbul, Turkey.
authors.forename: Hakan
authors.initials: H
authors.lastname: Bilhan
authors.affiliation: Istanbul Technical University, Faculty of Mechanical Engineering, Laboratory of Biomechanics, Istanbul, Turkey.
authors.forename: Gokhan
authors.initials: G
authors.lastname: Baysal
authors.affiliation: Istanbul Technical University, Faculty of Mechanical Engineering, Laboratory of Biomechanics, Istanbul, Turkey.
authors.forename: Emin
authors.initials: E
authors.lastname: Sunbuloglu
authors.affiliation: Istanbul Technical University, Faculty of Mechanical Engineering, Laboratory of Biomechanics, Istanbul, Turkey.
authors.forename: Ergun
authors.initials: E
authors.lastname: Bozdag
keywords: Acrylic; Complete denture; Experimental stress analysis; Frenulum; Midline fracture; Strain gauge