Pulpal temperature rise: Evaluation after light activation of newer pulp-capping materials and resin composite

SUMMARY Objectives: To analyze the effect of pulp-capping materials and resin composite light activation on strain and temperature development in the pulp and on the interfacial integrity at the pulpal floor/pulp-capping materials in large molar class II cavities. Methods: Forty extracted molars received large mesio-occlusal-distal (MOD) cavity bur preparation with 1.0 mm of dentin remaining at the pulp floor. Four pulp-capping materials (self-etching adhesive system, Clearfil SE Bond [CLE], Kuraray), two light-curing calcium hydroxide cements (BioCal [BIO], Biodinâmica, and Ultra-Blend Plus [ULT], Ultradent), and a resin-modified glass ionomer cement– (Vitrebond [VIT], 3M ESPE) were applied on the pulpal floor. The cavities were incrementally restored with resin composite (Filtek Z350 XT, 3M ESPE). Thermocouple (n=10) and strain gauge (n=10) were placed inside the pulp chamber in contact with the top of the pulpal floor to detect temperature changes and dentin strain during light curing of the pulp-capping materials and during resin composite restoration. Exotherm was calculated by subtracting postcure from polymerization temperature (n=10). Interface integrity at the pulpal floor was investigated using micro-CT (SkyScan 1272, Bruker). The degree of cure of capping materials was calculated using the Fourier transform infrared and attenuated total reflectance cell. Data were analyzed using one-way analysis of variance followed by the Tukey test (α=0.05). Results: Pulpal dentin strains (μs) during light curing of CLE were higher than for other pulp-capping materials (p<0.001). During resin composite light activation, the pulpal dentin strain increased for ULT, VIT, and CLE and decreased for BIO. The pulpal dentin strain was significantly higher during pulp-capping light activation. The temperature inside the pulp chamber increased approximately 3.5°C after light curing the pulp-capping materials and approximately 2.1°C after final restoration. Pulp-capping material type had no influence temperature increase. The micro-CT showed perfect interfacial integrity after restoration for CLE and ULT; however, gaps were found between BIO and pulpal floor in all specimens. BIO had a significantly lower degree of conversion than ULT, VIT, and CLE. Conclusions: Light curing of pulp-capping materials caused deformation of pulpal dentin and increased pulpal temperature in large MOD cavities. Shrinkage of the resin composite restoration caused debonding of BIO from the pulpal floor.

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Comparison of Composite Curing Parameters: Effects of Light Source and Curing Mode on Conversion, Temperature Rise and Polymerization Shrinkage

Operative Dentistry ◽

10.2341/05-15 ◽

2006 ◽

Vol 31 (2) ◽

pp. 219-226 ◽

Cited By ~ 38

Author(s):

Z. Tarle ◽

A. Knezevic ◽

N. Demoli ◽

A. Meniga ◽

J. Sutalo ◽

...

Keyword(s):

Light Source ◽

Temperature Rise ◽

Thermal Injury ◽

Resin Composite ◽

Marginal Adaptation ◽

Low Intensity ◽

Halogen Light ◽

Lower Temperature ◽

Final Degree ◽

Conversion Temperature

Clinical Relevance The use of a low intensity light source for photopolymerization based on LED technology provides equivalent final degree conversion with possible flow of the resin composite, similar to when QTH technology is used. At the same time, the lower temperature rise in the sample and the more favorable development of shrinkage kinetics compared to the higher intensities of halogen light may aid in maintaining marginal adaptation while avoiding possible thermal injury.

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Pulpal-temperature Rise and Polymerization Efficiency of LED Curing Lights

Operative Dentistry ◽

10.2341/09-203-l ◽

2010 ◽

Vol 35 (2) ◽

pp. 220-230 ◽

Cited By ~ 73

Author(s):

J. Leprince ◽

J. Devaux ◽

T. Mullier ◽

J. Vreven ◽

G. Leloup

Keyword(s):

Temperature Rise ◽

Clinical Relevance ◽

Pulp Chamber ◽

Pulpal Temperature

Clinical Relevance This paper provides practitioners with useful information on the importance of aligning the spectra of the LCU and the material in terms of polymerization efficiency and temperature rise in the pulp chamber.

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Shear Bond Strength of a Resin Composite to Six Pulp Capping Materials Used in Primary Teeth

Journal of Clinical Pediatric Dentistry ◽

10.17796/1053-4625-44.4.4 ◽

2020 ◽

Vol 44 (4) ◽

pp. 234-239

Author(s):

Latifa Alhowaish ◽

Fouad Salama ◽

Mohammed Al-Harbi ◽

Mohamad Abumoatti

Keyword(s):

Bond Strength ◽

Shear Bond Strength ◽

Primary Teeth ◽

Resin Composite ◽

Testing Machine ◽

Bond Failure ◽

Pulp Capping ◽

Machine Failure ◽

Materials Used

Aim: The purpose of this in vitro study was to assess the shear bond strength (SBS) and bond failure types of a resin-composite to six pulp-capping materials used in primary teeth. Study design: Eight-disc specimens from each pulp-capping material (6 groups) to bond to Filtek™ Z350 XT Flowable using a standard PVC tube (2×2mm). All groups were prepared according to the instruction of the manufacturer. The SBS was measured with a crosshead speed of 0.5 mm/min using a universal testing machine. Failure mode evaluation was completed using Digital Microscope by two independent examiners. Results: Urbical LC® showed the highest SBS (Mean±SD) followed by ProRoot® MTA and TheraCal LC® (35.422±2.910, 22.114±2.515, and 21.175±1.983) respectively. ANOVA showed significant differences between all groups (P=0.0001). Urbical LC® and Photac™ Fil QuickAplicap™ were statistically significant different from all other pulp-capping materials groups. ProRoot® MTA was statistically significant different than Biodentine® (P=0.0001) and Photac™ Fil (P=0.0001). The total number of bond failure was recorded for cohesive B failure/cohesive in the pulp-capping material (14) and adhesive failure (14). Conclusion: Most of the tested pulp-capping materials bonded to Filtek™ Z350 XT demonstrated clinically acceptable and high SBS. Urbical LC showed the highest SBS while Biodentine® showed the lowest SBS.

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Effects of different dentin thicknesses and air cooling on pulpal temperature rise during laser welding

Lasers in Medical Science ◽

10.1007/s10103-012-1108-1 ◽

2012 ◽

Vol 28 (1) ◽

pp. 167-170 ◽

Cited By ~ 14

Author(s):

Asli Secilmis ◽

Mehmet Bulbul ◽

Tugrul Sari ◽

Aslihan Usumez

Keyword(s):

Laser Welding ◽

Temperature Rise ◽

Air Cooling ◽

Pulpal Temperature

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Tooth bleaching effect by light activation on the tooth surface and intra-pulpal temperature: an in vitro study

Journal of Korean society of Dental Hygiene ◽

10.13065/jksdh.2014.14.04.585 ◽

2014 ◽

Vol 14 (4) ◽

pp. 585-591 ◽

Cited By ~ 1

Author(s):

Youn-Soo Shim ◽

Hee-Sun Woo

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Tooth Bleaching ◽

Tooth Surface ◽

Light Activation ◽

Bleaching Effect ◽

Pulpal Temperature

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Influence of softening test and light-activation protocols on resin composite polymer structure

European Journal of Dentistry ◽

10.4103/1305-7456.126233 ◽

2014 ◽

Vol 08 (01) ◽

pp. 009-014 ◽

Cited By ~ 2

Author(s):

Maria Cecília Caldas Giorgi ◽

Débora Alves Nunes Leite Lima ◽

Giselle Maria Marchi ◽

Gláucia Maria Ambrosano ◽

Flávio Henrique Baggio Aguiar

Keyword(s):

Repeated Measures ◽

Light Emitting Diode ◽

Resin Composite ◽

Absolute Ethanol ◽

Infrared Spectrometry ◽

Control Group ◽

Light Activation ◽

Experimental Conditions ◽

Storage Media ◽

Split Plot

ABSTRACT Objective: This study analyzed the influences of the light-activation protocol and softening test on the degree of conversion (DC) and Knoop Hardness (KHN) of a microhybrid resin composite. Materials and Methods: Filtek Z250 (3M ESPE) was light-activated with a third-generation light-emitting diode (Valo Ultradent) by three protocols – standard, high power, and plasma emulation – or with a quartz-tungsten halogen XL 3000 (3M ESPE) in conventional mode. All modes were set to deliver 19 J/cm2. The DC (N = 20) was determined by Fourier transform infrared spectrometry on the top (T) and bottom (B) surfaces. For the KHN test, samples were subdivided in four groups (n = 5 each) according to the storage media: absolute ethanol, 75% ethanol, distilled water, and air (control group). The KHN values were evaluated on T and B before and 24 h after immersion in the storage media. Data were analyzed by split-plot analysis of variance (ANOVA; for DC) or repeated-measures split-plot ANOVA (for KHN), followed by Tukey's test (α = 0.05). Results: For the DC, the light-activation protocol did not influence the results and there was no difference between T and B. For the KHN test, the light-activation protocol did not influence the results and T showed higher microhardness values than B for all experimental conditions. There were significant differences in KHN depending on the storage media. Samples immersed in absolute ethanol generally presented lower KHN values, with no differences compared to samples in 75% ethanol. Conclusion: The storage media affected the outcomes of the softening test.

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