246 Degree of Conversion of Nano-hybrid-resin-based-composites with Novel and Conventional Matrix-formulation

Thursday, March 22, 2012: 2 p.m. - 3:15 p.m.
Presentation Type: Poster Session
N. ILIE, and K. FRAUSCHER, Dental School, Ludwig-Maximilians-University, Munich, Germany

Objectives: to determine the degree of conversion (DC) of two nano-hybrid resin-composites with novel monomer components based on dimer-acid-derivates (h-Da) and tricyclodecane-urethane (TCD-urethane) structure in comparison to three nano-hybrid materials containing conventional matrices.

Materials and Methods: DC was evaluated in real-time (5min, 2spectra/s) by an FTIR-spectrometer with attenuated total reflectance (ATR) accessory at 0.1mm, 2mm and 6mm depth at varying irradiation times (10s, 20s, 40s, LED Freelight2, 1,241 mW/cm²) and layering-techniques (bulk, incremental).

Results: were compared using one- and multiple-way ANOVA and Tukey HSD post-hoc test (α=0.05) and partial eta-squared statistic. Statistical analysis was made respectively within one geometry (vertically, shown by the superscript letters in the table, e.g. A, B or α, β), as well as within all geometries for each material and irradiation time (horizontally, shown by star-symbols). Specimen geometry revealed a strong effect on DC (η2=0.90) followed by curing time (η2=0.39).

Material

Time[s]

DC0.1mm[%]

DC2mm[%]

DC6mm bulk[%]

DC6mm incr.[%]

Miris2/Coltène-Whaledent

10

52.00CD***(2.38)

49.06b**(1.74)

3.98ΑΒ*(3.61)

47.85βγ**(1.87)

20

53.62DE***(1.56)

54.39cd***(3.20)

26.32E*(3.87)

46.52β,γ,d**(11.93)

40

54.26DE **(1.47)

56.14de**(1.46)

41.42G*(5.04)

55.03ε **(1.51)

N'Durance/Septodont

10

58.93F***(1.72)

56.77de**,***(2.47)

17.45D*(7.91)

54.18ε,ζ**(2.65)

20

59.27F**,***(1.41)

59.67ef***(1.46)

36.41F*(5.90)

56.50 ζ,η**(3.47)

40

60.91F**(2.20)

58.69ef**(3.64)

50.39H*(3.41)

60.00η**(2.40)

Premise/Kerr

10

60.48F****(3.69)

54.37cd ***(4.17)

3.32AB*(3.32)

42.58αβγ **(7.26)

20

61.45F****(2.04)

58.46ef***(2.07)

1.18A*(1.69)

55.86ζ,η**(4.77)

40

61.58 **(2.93)

61.03f**(2.22)

13.87CD*(7.46)

57.79 ζ,η **(2.86)

Simile/Jeneric Pentron

10

54.72DE ***(2.12)

44.17a**(4.59)

3.11AB*(3.09)

41.95αβ**(2.30)

20

54.90DE ****(2.15)

51.18bc***(2.82)

9.08BC*(5.21)

46.25βγd **(2.38)

40

55.56E ***(2.08)

50.98bc**(1.78)

25.81E *(4.75)

50.15dε**(4.65)

Venus Diamond/Kulzer

10

46.80A***(4.31)

44.20a***(6.82)

11.26CD*(6.67)

38.07α**(4.07)

20

47.41AB***(4.12)

49.37b***(4.34)

26.66E *(7.15)

42.73αβγ**(4.41)

40

49.94BC***(3.81)

50.57bc***(3.61)

31.26EF*(7.65)

45.52βγd**(3.42)

Conclusions: increments of 2mm and irradiation-time of at least 20s still must be recommended for clinical practice. The two materials containing novel monomer-composition might be applied for enlarged increments because of the low decrease of DC they demonstrated.

 

 


Keywords: Biomaterials, Curing lights and Dental materials