• Guimarães, Gustavo Narvaes
• Cardoso, Guinéa Brasil Camargo
• Marques, Marcelo Rocha
• Line, Sergio Roberto Peres
• Naves, Lucas Zago
• Correr-Sobrinho, Lourenço

Abstract

<p>OBJECTIVE: The purpose of this study is to investigate the effects of intermittent parathyroid hormone (PTH) administration on the apposition rate and structural features of dentine from mouse incisors.</p><p>METHODS: Young male A/J Unib mice were treated daily for 6 and 10 days with 40 μg/kg of hPTH 1-34 or a vehicle. Dentine apposition rates measured by fluorescent labels (tetracycline and calcein) and alkaline phosphatase (ALP) plasma levels were evaluated after 6 days of treatment. Knoop microhardness testing and element content measurements in at.% of calcium (Ca), phosphorus (P), oxygen (O), and magnesium (Mg) in the peritubular and intertubular dentine were performed by Energy Dispersive X-ray (EDX) microanalysis via Scanning Electron Microscopy (SEM) after 10 days of treatment.</p><p>RESULTS: Histometric analysis revealed an increase of 5% in the apposition rate of dentine and 25% in the ALP plasma levels in the PTH treated group. In addition, knoop microhardness testing revealed that the animals treated with PTH had a greater microhardness (11%). EDX microanalysis showed that PTH treatment led to increases in P (23%) and Ca (53%) at.% content, as well as the Ca/P ratio (24%) in peritubular dentine. The chemical composition of intertubular dentine did not vary between the groups.</p><p>CONCLUSIONS: These findings indicate that intermittent administration of hPTH (1-34) increases apposition and mineralization of the dentine during young mice incisor formation.</p>

Topics

• impedance spectroscopy
• scanning electron microscopy
• Oxygen
• Magnesium
• Magnesium
• chemical composition
• Energy-dispersive X-ray spectroscopy
• Calcium
• Phosphorus