Evaluation of GCF MMP-1, -8 and Growth Factor Levels in Smokers With Periodontal Health

The main objective of the present study was to investigate the GCF levels of MMP-1, MMP-8, TGF-β1, PDGF-AB and VEGF in smoker versus non-smoker periodontally healthy young adults.

A total of 32 periodontally healthy young adults including 16 smokers and 16 non-smokers, were recruited for the present cross-sectional study ( 18 female and 14 males; age range: 19 to 27 years).

All participants had a thorough full-mouth clinical examination. The measurement of probing depth (PD) and clinical attachment level (CAL) were assessed at six sites per tooth in the whole mouth, excluding third molars in all study participants. Bleeding on probing (BOP) and the amount of plaque accumulation were also evaluated.

GCF sampling sites were selected from the sites without BOP and plaque accumulation. GCF samples were obtained from buccal aspects of proximal sites in a single-rooted teeth in each individual participating in the present study. Paper strips† were carefully inserted 1 mm into the crevice for 30 seconds. Care was taken to avoid mechanical trauma. The absorbed GCF volume was estimated by a calibrated instrument. Then each strip from each patient were placed into one polypropylene tube before freezing at -40°C. The readings were converted to an actual volume (µl) reference to the standard curve. All GCF samples were stored at -40°C until the laboratory analyses.

Considering a difference of 50% in mean GCF levels of the biochemical markers and assuming standard deviations to be maximum 80% of the mean values and accepting a power of 90%, P value of 5% in smoker and non-smoker groups, minimum sample size was calculated.