Optical microscopy observations revealed that the color change was limited to surface discoloration due to the fiber reinforcement limiting degradation to the surface polymer matrix microstructure even after extended UV-exposure.
Most automated lumber grading discrepancies resulted from board geometry related issues (e.g. board crook, surface measure rounding, calculation of cutting units, etc).. Concerning the multiple sensor scanning system, defect recognition improvements should focus on better methods to differentiate surface discoloration from critical grading defects.
The observed visual damage consisted of surface discolorations at low shock load levels and progressed to surface fiber breakage accompanied by internal delaminations and breakage of the through thickness (Z-directional) fibers at higher shock load levels.
Results found a threshold and beyond this threshold various microscopic changes were seen at surface including discoloration, pitting and fusing of fibres.
Studies have pointed to issues related to degradation of materials science characteristics for veneering composites that are distinct from those associated with porcelain, including loss of glossiness because of the deterioration of the surface and discoloration, wear, and attrition due to long-term use [47].
However, the addition of organo-phosphite 'S' in the phenol and phenol-free systems (C, CT, CX and CTX) exhibited synergistic effects of stabilization against embrittlement, discoloration, surface erosion and oxidation.
In comparison with iPP and EP copolymers matrices, it can be found that the trend in stabilizing efficiency against embrittlement, discoloration, surface crack and oxidation is almost similar but the difference was observed only in the magnitude.
The evaluation of anatomic form, marginal adaptation, proximal contact, the resistance to marginal discoloration, surface roughness, the absence of secondary caries, and post-operative pain yielded very satisfactory scores throughout the study.
Furthermore the characteristics of the restoration, including anatomic form of the restoration, marginal adaptation, quality of proximal contact, marginal discoloration, surface roughness, secondary decay, and post-operative pain were analysed.
Rough surfaces may cause discoloration of denture base material and may also contribute to biofilm formation because bacteria and fungus have more of a propensity to adhere to rough surfaces [ 33, 34].
One of the benefits of Corian, however, is that surface scratches and discolorations are easily removed.
