Spatial Variations in the Microstructure Of Radicular Dentin With Age
Objectives: Spatial variations in the microstructure of coronal dentin are important to its resistance to fracture and are age-dependent. Despite the incidence of fractures in the root, an equivalent evaluation of radicular dentin has not been reported. The objectives of this investigation were to evaluate the spatial variations in microstructure of radicular dentin from the root apex to the cemento-enamel junction, and assess its importance to the strength of this tissue. Methods: Single rooted teeth were obtained with approved and divided into young (age≤ 35), middle (354/Amide I), as well as the collagen cross-link ratio (1668 cm-1/1689 cm-1). The strength was assessed from beams extracted from the bucco-lingual quadrants and evaluated via 4-pt flexure to failure. Results: For the young group there was no spatial variation in the mineral to collagen ratio or the degree of collagen cross-linking in the root. There was a significant increase in the degree of crosslinking and the mineral to collagen ratio with age, which was concentrated in the apical third. The number of lumens filled with mineral and extent of sclerosis also increased with increasing age. The strength to fracture decreased significantly and by nearly 40% from the young to the old age group. Conclusions: There are significant increases in the mineral to collagen ratio and collagen cross-linking in radicular dentin with age. This is a progressive process that begins within the apical third and substantially reduces the resistance to fracture of the tooth root.
Division: IADR/AADR/CADR General Session
Meeting:2017 IADR/AADR/CADR General Session (San Francisco, California) Location: San Francisco, California
Year: 2017 Final Presentation ID:2133 Abstract Category|Abstract Category(s):Mineralized Tissue
Authors
Yan, Weishi
( University of Washington
, Seattle
, Washington
, United States
)
Montoya, Carolina
( Universidad EAFIT
, Medellin
, Colombia
)
Ossa, Alexander
( Universidad EAFIT
, Medellín
, Colombia
)
Romberg, Elaine
( University of Maryland
, Baltimore
, Maryland
, United States
)
Zhang, Hai
( University of Washington
, Seattle
, Washington
, United States
)
Arola, Dwayne
( University of Washington
, Seattle
, Washington
, United States
; University of Washington
, Seattle
, Washington
, United States
)