GCF HIF-1α, VEGF and TNF-α Levels in G-AgP Patients Before and After Periodontal Treatment.
Condition: Aggressive Periodontitis, Generalized; Periodontal Health
MeSH terms: Periodontitis; Aggressive Periodontitis; Aggression
Study type: Interventional

Summary: 
      Hypoxia-inducible angiogenic pathway involving hypoxia inducible factor-1 alpha (HIF-1α),
      vascular endothelial growth factor (VEGF) and tumour necrosis factor- alpha (TNF-α) may
      regulate the several biological processes related to inflammation. Generalized aggressive
      periodontitis (G-AgP) is a rare but highly destructive form of inflammatory periodontal
      disease. The present study aimed to assess the effect of non-surgical periodontal treatment
      on gingival crevicular fluid (GCF) HIF-1α, VEGF and TNF-α levels in G-AgP patients. 20 G-AgP
      and 20 periodontally healthy subjects were enrolled. At baseline, GCF samples were collected
      and whole mouth clinical periodontal parameters were recorded. G-AgP patients received
      non-surgical periodontal treatment. Clinical parameters and GCF cytokines were re-measured at
      1 and 3 months after treatment. GCF HIF-1α, VEGF and TNF-α levels were analyzed by ELISA.
      Data were analyzed using appropriate statistical tests.
    

Detailed description: 
      Study Population and Clinical Examination

      A total of 40 individuals were recruited for the present study. Inclusion criteria included:
      1) aged 25 to 45 years 2) non-smokers with no history of smoking 3) having at least 20
      natural teeth. Exclusion criteria were as follows: 1) having any diagnosed medical disorders
      such as diabetes mellitus, cardiovascular diseases, rheumatoid arthritis, immunological and
      mucocutaneous diseases 2) usage of antibiotics, non-steroidal anti-inflammatory drugs and
      immunosuppressive agents within the past 6 months 3) having any non-inflammatory destructive
      periodontal disease 4) nonsurgical/surgical periodontal therapy received in the past year 5)
      having a restorative and endodontic treatment requirement 6) having orthodontic appliances or
      a removable partial denture 7) pregnant/ lactating/ postmenopausal females.

      The whole mouth clinical periodontal examination included measurement of probing depth (PPD),
      clinical attachment level (CAL), presence of bleeding on probing (BOP), gingival index (GI)
      and plaque index (PI) at 6 sites per tooth, except the third molars. The presence and type of
      the alveolar bone loss were assessed on the digital panoramic radiograph in each participant,
      which was supplemented with periapical radiographs if necessary.

      Periodontal status of each patient was evaluated by a single calibrated periodontists with a
      manual probe. The diagnosis of G-AgP or periodontally health was determined according to the
      International Classification of Periodontal Diseases in 1999. The patients in G-AgP group
      (n=20) had a minimum three teeth apart from the first molars and incisors showing CAL ≥5 mm
      and PPD ≥6 mm. Radiographic bone loss was ≥30 % of root length affecting ≥3 teeth other than
      first molars and incisors. This generalized pattern of severe destruction was inconsistent
      with the amount of microbial deposits. Patients had at least one other family member
      presenting with or having a history of severe periodontal problems. Periodontally healthy
      individuals (n=20) in the control group had no sites with PPD >3 mm and CAL >2 mm and also no
      radiographic evidence of alveolar bone loss. BOP was <15% in the whole mouth.

      Treatment

      The recruited G-AgP patients received conventional quadrant scaling and root planning (SRP)
      under local anaesthesia for 3 weeks. SRP was performed by the same periodontist (who was
      different the investigator recorded periodontal parameters) using ultrasonic inserts and
      manual periodontal curettes. Re-evaluations were performed at 1 and 3 months following the
      completion of the SRP in the lower right quadrant. No periodontal intervention was carried
      out in the periodontally healthy controls.

      GCF sampling

      GCF was sampled from two deepest pockets of single-rooted teeth at baseline in G-AgP group
      immediately before the treatment of upper right quadrant. Sampling was repeated at the same
      sites following the completion of the SRP in the lower right quadrant. GCF was sampled from
      the buccal aspects of two nonadjacent interproximal sites in single-rooted teeth with.
      Samples were collected from the sites without BOP in the periodontally healthy group.
      Standardized filter paper strips were used for GCF sampling. Sterile paper strips were gently
      inserted into the gingival sulcus or pocket until mild resistance was felt and left there for
      30 s. The absorbed fluid volume was measured with a precalibrated electronic device. The
      paper strips were stored at -40◦C for further analysis.

      Measurement of HIF-1α, VEGF and TNF-α Levels in GCF

      Two paper strips were pooled, placed in 300 µL PBS-T (0.05%). HIF-1α, VEGF and TNF-α levels
      in GCF samples were measured by the enzyme-linked immunosorbent assay using commercial kits
      in line with the manufacturer's guidelines. GCF results were expressed as both total amounts
      at two sites per sampling time.

      Statistical Analysis

      All statistical analyses were carried out with the standard statistical software package. For
      the intra-group comparisons, if the data were not normally disturbed, Friedman test and the
      Dunn test with the Bonferroni correction were used to analyze the change between baseline and
      1 month and 3 months after treatment. For inter-group comparisons, Mann-Whitney U test for
      normally and non-normally disturbed data. The Spearman's rank correlation test was used to
      detect the correlations of biochemical parameters with clinical parameters and each others in
      diseased group before and after treatment. All tests were performed at significance level of
      P <0.05.
    

Intervention name(s): Non-surgically performed scaling and root planing
Intervention type(s): Procedure
Intervention description(s): Non-surgically performed scaling and root planing
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: aggressive periodontitis; gingival crevicular fluid; hypoxia; cytokines