Gingival crevicular fluid alkaline phosphatase activity as a non-invasive biomarker of skeletal maturation.

OBJECTIVES: To evaluate the gingival crevicular fluid (GCF) alkaline phosphatase (ALP) activity in growing subjects in relation to the stages of individual skeletal maturation. SETTING AND SAMPLE POPULATION: The Department of Biomedicine, University of Trieste. Seventy-two healthy growing subjects (45 women and 27 men; range, 7.8-17.7\u2003years). MATERIALS AND METHODS: Double-blind, prospective, cross-sectional design. Samples of GCF were collected from each subject at the mesial and distal sites of both of the central incisors, in the maxilla and mandible. Skeletal maturation phase was assessed through the cervical vertebral maturation (CVM) method. Enzymatic activity was determined spectrophotometrically. RESULTS: The relationship between GCF ALP activity and CVM stages was significant. In particular, a twofold peak in enzyme activity was seen at the CS3 and CS4 pubertal stages, compared to the pre-pubertal stages (CS1 and CS2) and post-pubertal stages (CS5 and CS6), at both the maxillary and mandibular sites. No differences were seen between the maxillary and mandibular sites, or between the sexes. CONCLUSIONS: As an adjunct to standard methods based upon radiographic parameters, the GCF ALP may be a candidate as a non-invasive clinical biomarker for the identification of the pubertal growth spurt in periodontally healthy subjects scheduled for orthodontic treatment