Estimation of Serum Parathyroid Hormone Related Protein in the Assessment of Pubertal Growth Spurt in Skeletal Class II Malocclusion Subjects.

Abstract

Introduction: Accurate measurement of skeletal maturity is critical to the optimal treatment timing of skeletal jaw discrepancies. Skeletal maturity can be assessed by several radiologic biologic indicators such as orthopantomograph, middle phalanx of third finger (MP3), hand-wrist radiograph and cervical vertebral maturation indicators (CVMI), but since they are highly subjective techniques to identify peak mandibular growth, a quest for a reliable non-radiologic biologic marker was deemed necessary. Parathyroid Hormone related Protein (PTHrP) was chosen to assess the skeletal maturity as its evidence was scarce in literature. Materials and Methods: The sample consisted of 80 skeletal Class II malocclusion subjects, males (n= 38), females (n=42), aged 11–18 years. The cervical stage of each subject was assessed with a lateral cephalogram. Two mL blood was obtained by venipuncture. Serum PTHrP was quantitatively assessed by ELISA-Sandwich principle using Elabscience, ELISA kit. Results: Mean PTHrP serum levels in males witnessed an increase in CS3 & in females in CS2 followed by CS5, exhibiting a pubertal trend in males and a pre-pubertal trend in females. Mean PTHrP serum levels in the four intervals of cervical staging showed an increase in CS2 through to CS4 in males and in CS2-CS3 in females, showing an increase of this biomarker in the pre and pubertal stages in both the sexes. Conclusions: PTHrP mean serum levels was found to be increased in early rather than in the later stages of puberty in both males and females leading to the speculation that PTHrP could serve as a potential biomarker to assess the pubertal growth spurt.