title: Association of Neutral Zone Position with Age, Gender, and Period of Edentulism.
abstract: OBJECTIVE
  The changing dynamics of an aging mouth influence the position of the neutral zone (NZ). While the advantage of the NZ concept in complete denture treatment is quite established, what is not clearly understood is its position in relation to the crest of the residual ridge due to conflicting reports from previous studies. The purpose of this study was to investigate the distance and direction of NZ position in relation to crest of the residual ridge in edentulous patients and its association with age, gender, and period of edentulism.
  
  
  METHODS
  A cross-sectional study was conducted in 133 patients (70 males, 63 females) with a mean age of 58.81 ± 11.78 years. NZ recording was done using admix material by following standard procedures. Two metallic wires were adapted, one on the ridge and another on the center of the occlusal rims, and standardized digital radiographs were made. The position of NZ in relation to the crest of the residual ridge was recorded by noting the direction and measuring the distance between the adapted wires digitally at five locations (right molar, right premolar, incisor, left molar, left premolar regions).
  
  
  RESULTS
  Age, gender, and period of edentulism had no significant association with the position of NZ. No specific trend was observed in the in NZ position with a non-significant correlation.
  
  
  CONCLUSIONS
  Distance and the direction of neutral zone position in relation to crest of the residual ridge in edentulous patients bear no significant relationship with factors such as age, gender, and period of edentulism.
authors.affiliation: Department of Prosthetic Dentistry, College of Dentistry, Jazan University, Jazan, Kingdom of Saudi Arabia.
authors.forename: Amit
authors.initials: A
authors.lastname: Porwal
authors.affiliation: Department of Periodontics and Oral Implantology, Institute of Dental Sciences, Siksha 'O' Anusandhan University, Bhubaneswar, Odisha, India.
authors.forename: Anurag
authors.initials: A
authors.lastname: Satpathy
authors.affiliation: Department of Prosthodontics. College of Pharmacy and Dentistry, Buraydah Colleges, Buraydah, Kingdom of Saudi Arabia.
authors.forename: Preet
authors.initials: P
authors.lastname: Jain
authors.affiliation: Department of Prosthodontics, Krishnadevaraya College of Dental Sciences, Bangalore, Karnataka, India.
authors.forename: Ajjikuttira Appanna
authors.initials: AA
authors.lastname: Ponnanna
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000539:Alveolar Process / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D003430:Cross-Sectional Studies; D003824:Denture, Complete; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009066:Mouth, Edentulous / Q000000981:diagnostic imaging / Q000628:therapy*; D019252:Radiography, Dental, Digital; D012737:Sex Factors
keywords: Neutral zone; complete denture; edentulism; period of edentulism