title: Characterization of patients presenting for treatment to a university refractory periodontal diseases unit: three case reports.
abstract: BACKGROUND
  Of the many forms of periodontal disease, refractory periodontal diseases are the least characterized. They are defined as the continued degeneration of the periodontium despite adequate management. This has led to the suggestion that there may be a systemic component that is a contributing factor to the development of this condition. The objectives of this report were to follow the progression of clinical changes associated with periodontal disease over a number of years in this unique population and review various hematologic and microbiologic factors that may be contributing to the disease progression.
  
  
  METHODS
  Three subjects were profiled. They were referred to the Refractory Periodontal Disease Unit at the University of Toronto by periodontists or general practitioners in the Southern Ontario region. Complete medical and dental histories were obtained along with baseline clinical measurements. Periodontal examinations were facilitated with the use of a computer-assisted periodontal probe. A microbiologic analysis using immunofluorescence techniques was able to detect Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Actinobacillus actinomycetemcomitans and spirochetes. A hematologic analysis, including a complete blood count (CBC), immune profile, and glycosylated hemoglobin assay, was also performed.
  
  
  RESULTS
  The clinical presentation revealed that patients receiving adequate maintenance therapy and with good to excellent oral hygiene demonstrated sites with continual loss of attachment. Few periodontal pathogens were detected. However, the most significant finding appeared to be the report elevated levels of CD8+ cells within this group of patients compared to normal laboratory ranges.
  
  
  CONCLUSIONS
  This report is an attempt at characterizing a unique population within the periodontal realm. The long-term monitoring of these patients allowed for an assessment of factors that may be involved in the continued decline of the periodontal health of these patients. Based on the immune profile, it is possible that a hyperresponsive state may be the primary feature of this population. Future assessments, including full-mouth interleukin (IL)-1 and matrix metalloproteinase (MMP)-8 levels, may assist in characterizing this population further, with the goal of producing markers that will assist clinicians in predicting treatment outcome.
authors.affiliation: Department of Laboratory Medicine and Pathobiology, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.
authors.forename: Vinay M
authors.initials: VM
authors.lastname: Bhide
authors.forename: Howard C
authors.initials: HC
authors.lastname: Tenenbaum
authors.forename: Michael B
authors.initials: MB
authors.lastname: Goldberg
mesh_terms: D000328:Adult; D016976:Aggregatibacter actinomycetemcomitans / Q000302:isolation & purification; D001439:Bacteroides / Q000302:isolation & purification; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000473:pathology; D003936:Diagnosis, Computer-Assisted; D018450:Disease Progression; D005260:Female; D005455:Fluorescent Antibody Technique; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D008297:Male; D017622:Periodontal Attachment Loss / Q000503:physiopathology; D010510:Periodontal Diseases / Q000503:physiopathology*; D010517:Periodontics / Q000295:instrumentation; D016966:Porphyromonas gingivalis / Q000302:isolation & purification; D018713:Prevotella intermedia / Q000302:isolation & purification; D012008:Recurrence; D013144:Spirochaetales / Q000302:isolation & purification
chemical_list: D006442:Glycated Hemoglobin