Statistical estimation of resin composite polymerization sufficiency using microhardness

Cohen, Mark E.; Leonard, Daniel L.; Charlton, David; Roberts, Howard W.; Ragain, James C.

doi:10.1016/s0109-5641(03)00087-3

Cited by 19 publications

(14 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Microhardness measurements were used as an indirect method to assess the extent of polymerization in the resin material inside the cavity [22]. Immediately after the ESPI test, each specimen was sectioned along its mesio-distal axis using a low speed diamond saw (Isomet, Buehler, Lake Bluff, USA) to allow the comparison of Vickers microhardness (VHN) at the surface and depth of the resin material.…”

Section: Microhardness Analysismentioning

confidence: 99%

Dynamics of composite polymerization mediates the development of cuspal strain

et al. 2006

View full text Add to dashboard Cite

d e n t a l m a t e r i a l s 2 2 ( 2 0 0 6 ) 896-902 a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m j o u r n a l h o m e p a g e : w w w . i n t l . e l s e v i e r h e a l t h . c o m / j o u r n a l s / d e m a Objectives. In the current study, we used electronic speckle pattern interferometry (ESPI) to measure tooth deformation in response to polymerization of five resin composites with a range of polymerization shrinkage. Our hypothesis was that composites with higher polymerization shrinkage should cause more cuspal strain as measured by ESPI.Methods. Standardized MOD cavities were prepared and placed into the ESPI apparatus before the cavities were filled with composites (n = 10). The ESPI apparatus was constructed to measure the out-of-plane displacement of the lingual cusps of the teeth during the polymerization of the restorative material. A thermocouple was attached to the specimen to monitor thermal changes throughout the polymerization process. Results. Experiments with empty preparations demonstrated that the ESPI technique wastemporally responsive and sensitive to dimensional changes. However, the correlation between polymerization shrinkage of composite resins and ESPI-measured tooth deformation was not straightforward. In particular, a flowable material did not deform the tooth significantly more that a conventional hybrid. Further, an experimental silorane material (with the lowest axial shrinkage) induced the least tooth deformation.Significance. We concluded that ESPI is a viable method for assessing cuspal strain induced by shrinkage of bonded composite restorations, but that polymerization shrinkage data may overestimate shrinkage-induced tooth deformation. The rate of polymerization shrinkage appeared to mediate the development of cuspal strain.

show abstract

Section: Microhardness Analysismentioning

confidence: 99%

Dynamics of composite polymerization mediates the development of cuspal strain

et al. 2006

View full text Add to dashboard Cite

show abstract

“…A exponential polymerization kinetics model (23,24) was used to relate the anisotropy r(t) as a function of the polymerization time:…”

Section: Anisotropy Vs Polymerization Timementioning

confidence: 99%

Fluorescence anisotropy studies of molecularly imprinted polymers

et al. 2005

View full text Add to dashboard Cite

A molecularly imprinted polymer (MIP) is a biomimetic material that can be used as a biochemical sensing element. We studied the steady-state and time-resolved fluorescence and fluorescence anisotropy of anthracene-imprinted polyurethane. We compared MIPs with imprinted analytes present, MIPs with the imprinted analytes extracted, MIPs with rebound analytes, non-imprinted control polymers (non-MIPs) and non-MIPs bound with analytes to understand MIP's binding behaviour. MIPs and non-MIPs had similar steady-state fluorescence anisotropy in the range 0.11-0.24. Anthracene rebound in MIPs and non-MIPs had a fluorescence lifetime of tau = 0.64 ns and a rotational correlation time of phi(F) = 1.2-1.5 ns, both of which were shorter than that of MIPs with imprinted analytes present (tau = 2.03 ns and phi(F) = 2.7 ns). The steady-state anisotropy of polymer solutions increased exponentially with polymerization time and might be used to characterize the polymerization extent in situ.

show abstract

“…The non-linear regression utilized to estimate cure time and hardness ratios has been shown to be superior to linear regression in describing the relationship between exposure duration required to achieve 80% bottom-surface hardness, relative to top surface H MAX . 18 Non-linear regression analysis utilizing maximum top-surface hardness provides a more accurate method to assess the curing behavior of various resin composites (while holding the LCU constant) or to assess the curing effectiveness of various LCUs (while holding the composite constant). It is suggested that the methodology described be adopted as a more accurate indicator of adequacy of cure when evaluating various curing-light/composite combinations.…”

Section: Discussionmentioning

confidence: 99%

“…A 2004 study by the same authors proposed an alternative statistical description of the relationship between resin polymerization sufficiency and exposure duration. 18 Referring to their 2002 study, it was observed that the curvature in the early and late cure intervals data obtained for hardness ratios tended to be below the linear regression line. A non-linear regression model provided a better estimate of the exposure duration required to achieve adequate resin composite polymerization.…”

Section: Introductionmentioning

confidence: 96%

Describing Adequacy of Cure with Maximum Hardness Ratios and Non-linear Regression

Bouschlicher

Berning²,

Qian³

2008

Operative Dentistry

View full text Add to dashboard Cite

Redefined hardness ratios, based on extended cure intervals and maximum hardness when used in conjunction with non-linear regression, provide a readily available and accurate characterization of the curing performance of LCU-composite combinations, which is superior to the use of traditional per-specimen hardness ratios. It is recommended that the light curing guidelines provided to clinicians should be based on this more accurate description of curing behavior. SUMMARY Knoop Hardness (KH) ratios (HR)≥

show abstract

Statistical estimation of resin composite polymerization sufficiency using microhardness

Cited by 19 publications

References 10 publications

Dynamics of composite polymerization mediates the development of cuspal strain

Dynamics of composite polymerization mediates the development of cuspal strain

Fluorescence anisotropy studies of molecularly imprinted polymers

Describing Adequacy of Cure with Maximum Hardness Ratios and Non-linear Regression

Contact Info

Product

Resources

About