Comparison of vehicles to collect dentinal fluid for molecular analysis

Abstract

OBJECTIVES To test the hypothesis that a material with higher water absorption than polyvinylidene fluoride (PVDF) could increase the yield of target molecules from exposed dentine. METH-ODS In a series of standard tests, different cellulose membranes were compared to a PVDF counterpart for their ability to absorb water and release protein. In a subsequent randomized clinical trial, the cellulose material with the most favourable values was compared to PVDF regarding the levels of MMP-2 that could be collected from exposed dentine of healthy human teeth during filling replacement. MMP-2 levels were determined by enzyme-linked immunosorbent assay (ELISA). Data from the laboratory experiments were compared between materials using the appropriate parametric tests. The frequency of cases yielding quantifiable levels of MMP-2 was compared between materials by Fisher's exact test. The level of significance was set at 5%. RESULTS The cellulose membrane with the largest pore size (12-15 m) absorbed significantly (P<0.05) more water than PVDF. It showed a protein release that was similar to that of PVDF, while the cellulose membranes with smaller pore size retained significantly more protein (P<0.05). Using the large-pore cellulose membrane, MMP-2 could be collected at a quantifiable level from the dentine of healthy teeth in 9 of 13 cases, compared to 1 of 13 with the PVDF membrane (P<0.05). CONCLUSIONS Under the current conditions, a large-pore cellulose membrane yielded more of a molecule of diagnostic value compared to a standard PVDF membrane. CLINICAL SIGNIFICANCE Molecular diagnostics of dentinal fluid are hampered by low yields. In the current study, it was shown that cellulose membranes are more useful to collect MMP-2 from dentinal fluid than PVDF membranes. ABSTRACTObjectives: To test the hypothesis that a material with higher water absorption than polyvinylidene fluoride (PVDF) could increase the yield of target molecules from exposed dentin. Methods:In a series of standard tests, different cellulose membranes were compared to a PVDF counterpart for their ability to absorb water and release protein. In a subsequent randomized clinical trial, the cellulose material with the most favorable values was compared to PVDF regarding the levels of MMP-2 that could be collected from exposed dentin of healthy human teeth during filling replacement. MMP-2 levels were determined by enzyme-linked immunosorbent assay (ELISA). Data from the laboratory experiments were compared between materials using the appropriate parametric tests. The frequency of cases yielding quantifiable levels of MMP-2 was compared between materials by Fisher's exact test. The level of significance was set at 5%. Results:The cellulose membrane with the largest pore size (12 -15 µm) absorbed significantly (P < 0.05) more water than PVDF. It showed a protein release that was similar to that of PVDF, while the cellulose membranes with smaller pore size retained significantly more protein (P < 0.05). Using the large-pore cellulose membrane, MM...

Biological Markers for Pulpal Inflammation: A Systematic Review

“…Dentin fluid is the extracellular fluid that is contained within dentinal tubules [109]; its composition includes inflammatory mediators and vasoactive compounds associated with inflammation. While initial evidence suggested that these mediators can be assayed [33] problems exist with protein yield [27] and the need to remove the existing restoration or in other cases to prepare an initial cavity deep in dentin.…”

“…Some research suggests that the dental pulp is not an isolated entity in an encased, solid environment but a reactive tissue that extends its biological products into the outside environment [24, 25]. In fact, studies have shown that pulpal events can be reflected through measurable levels of protein markers that correlated with pulpal symptoms in pulpal blood [26], dentinal fluid [27], periapical fluid [28], and gingival crevicular fluid (GCF; [1, 29]).…”

Pulpa: Beurteilung von Vitalität und Sensibilität

“…Die Pulpa gilt als ein reaktives Gewebe, das mit dem umliegenden Gewebe interagiert. Änderungen von Proteinmarkern im Pulpablut [49], im Dentinliquor [50], im apikalen Fluid [51] und in der Sulcusflüssigkeit [52], die mit pulpitischen Symptomen korrelierten, wurden bereits nachgewiesen. Bis jetzt hat die molekulare Diagnostik allerdings bei endodontischen Fragestellungen im Hinblick auf Diagnostik und Therapieplanung noch keinen Einzug in den klinischen Alltag gehalten [53].…”

Molecular diagnostics in endodontics

“…It would be most interesting to evaluate whether such assays could also be developed for the analysis of dentinal and periapical fluid. With the former, there will most likely be a sensitivity problem as the target proteins collected from dentinal fluid are in the low ng range . However, with periapical fluid, yields are similar to GCF and assays could easily be developed.…”