Radiotherapy alters the composition, structural and mechanical properties of root dentin in vitro

Autor(es)

De Amoedo Campos Velo, Marilia Mattar ^[1] ; Herrera Farha, Ana Laura ^[1] ; da Silva Santos, Paulo Sergio ^[2] ; Shiota, Aymee ^[1] ; Sansavino, Simone Zuquerato ^[3] ; Souza, Ana Tarsila ^[3] ; Honorio, Heitor Marques ^[4] ; Wang, Linda ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Bauru Sch Dent, Dept Operat Dent Endodont & Dent Mat, Al Dr Octavio Pinheiro Brisolla 9-75 Vila Univ, BR-17012901 Bauru, SP - Brazil

^[2] Univ Sao Paulo, Bauru Sch Dent, Dept Surg Stomatol Pathol & Radiol, Al Dr Octavio Pinheiro Brisolla 9-75 Vila Univ, BR-17012901 Bauru, SP - Brazil

^[3] Radiotherapy Ctr Reg Bauru, Sect Med Phys, Prof Nair Araujo Antunes St 1050, BR-17033495 Bauru, SP - Brazil

^[4] Univ Sao Paulo, Bauru Sch Dent, Dept Pediat Dent Orthodont & Publ Hlth, Al Dr Octavio Pinheiro Brisolla 9-75 Vila Univ, BR-17012901 Bauru, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: CLINICAL ORAL INVESTIGATIONS; v. 22, n. 8, p. 2871-2878, NOV 2018.
• Citações Web of Science: 5

Resumo

Objectives Post-radiation dental lesions affect mainly the cervical area of the tooth. Until now, there are quite few evidences regarding the effects of radiation exposure on root dentin breakdown. To better understand this effect, we used human root dentin specimens obtained from third molars from similarly aged individuals. Materials and methods Twenty specimens were analyzed by the surface hardness (SH), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) to evaluate the baseline properties of their root dentin. Other six human teeth were prepared and analyzed by scanning electron microscopy (SEM). Then the specimens were randomly distributed between two groups (n = 13 per group) and irradiated with a total dose of 55 or 70 Gy in a linear accelerator. The percentage of EDX and surface hardness loss (%SHL) were determined based on measurements before and after irradiation. The specimens were also analyzed after irradiation by SEM and XRD. The Ca/P weight ratio was calculated. Results Based on SEM analysis, radiation exposure induced dehydration of the dentin. The Ca/P weight ratio decreased (p = 0.0045). The % SHL of specimens irradiated with 70 Gy was higher than that of the 55-Gy group (p < 0.05), although even the lower dose induced root dentin breakdown. Conclusions Overall, we can state that radiation exposure changes the composition and structure of human root dentin, which detrimentally affect its hardness. (AU)

• Processo FAPESP: 15/00817-2 - Avaliação in vitro e in situ do efeito de dentifrícios fluoretados de alta concentração de fluoreto e a base de arginina no controle da cárie radicular
• Beneficiário: Marilia Mattar de Amoêdo Campos Velo
• Modalidade de apoio: Bolsas no Brasil - Doutorado