title: Influence of chronic alcoholism and oestrogen deficiency on the variation of stoichiometry of hydroxyapatite within alveolar bone crest of rats.
abstract: OBJECTIVE
  Previous findings suggest that chronic alcoholism and oestrogenic deficiency may affect bones in general (including alveolar bone) and increase individuals' susceptibility to the development of periodontal disease. The aim of this study was to assess possible alterations in the chemical composition of alveolar bone in rats subjected to chronic alcoholism, oestrogen deficiency or both.
  
  
  METHODS
  Fifty-four rats were initially divided into two groups: ovariectomized (Ovx), and Sham operated (Sham). A month after surgery, the groups were sub-divided and received the following dietary intervention for eight weeks: 20% alcohol, isocaloric diet and ad libitum diet. Samples of the mandible, in the alveolar bone crest region, were analyzed to verify possible changes in the stoichiometric composition of bone hydroxyapatite, by measuring the relationship between the concentration of calcium and phosphorus (Ca/P ratios), using micro X-ray fluorescence spectrometry.
  
  
  RESULTS
  The ad libitum groups presented the highest average values of Ca/P ratios, while the groups with dietary restrictions presented the smallest average values. The Ovx ad libitum group presented the highest values of Ca/P ratios (2.03 ± 0.04). However, these values were not considered statistically different (p>0.05) from the Sham ad libitum group (2.01 ± 0.01). The Ovx alcohol group presented lower values for Ca/P ratios (1.92 ± 0.06), being the only group statistically different (p<0.001) from the Sham ad libitum group. Potential confounding variables are discussed.
  
  
  CONCLUSIONS
  Ovariectomy associated with alcohol consumption at 20% significantly changed the stoichiometry composition of hydroxyapatite in the alveolar bone crest, leading to a reduction in Ca/P ratios.
authors.affiliation: Department of Biosciences and Diagnostics, São José dos Campos School of Dentistry, São Paulo State University - UNESP, São José dos Campos, São Paulo, Brazil. adrianampsmarchini@gmail.com
authors.forename: Adriana M P S
authors.initials: AM
authors.lastname: Marchini
authors.forename: Camila P
authors.initials: CP
authors.lastname: Deco
authors.forename: Karina B
authors.initials: KB
authors.lastname: Lodi
authors.forename: Leonardo
authors.initials: L
authors.lastname: Marchini
authors.forename: Ana M E
authors.initials: AM
authors.lastname: Santo
authors.forename: Rosilene F
authors.initials: RF
authors.lastname: Rocha
mesh_terms: D000437:Alcoholism / Q000378:metabolism*; D000539:Alveolar Process / Q000737:chemistry*; D000704:Analysis of Variance; D000818:Animals; D015519:Bone Density; D002118:Calcium / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry*; D004967:Estrogens / Q000172:deficiency*; D010052:Ovariectomy; D010758:Phosphorus / Q000737:chemistry; D051381:Rats; D013052:Spectrometry, X-Ray Emission; D018709:Statistics, Nonparametric
chemical_list: D004967:Estrogens; D010758:Phosphorus; D017886:Durapatite; D002118:Calcium