Comparative analysis of pulpal circulatory reaction to an acetone-containing and an acetone-free bonding agent as measured by vitalmicroscopy.

Despite great progress in the production of new dental polymers, application of these products is still controversial. The unlined utilization of cytotoxic adhesive materials on pulpal dentin can adversely influence the pulp, leading to alterations in local microcirculation that can be an early sign of pathological changes. In a previous study by the authors, the effect of an acetone-free bondmaterial was examined on the vascular diameter of pulpal vessels by means of vitalmicroscopy. In this study, experiments comparing experimental data provided by an acetone-containing bondmaterial to these earlier findings with acetone-free ones have been performed. Thirty male Sprague-Dawley rats (weighing 333+/-9 g) were used for this investigation. The first lower incisor was prepared for vitalmicroscopy. Changes in vessel diameter were recorded prior to and 5, 15, 30 and 60 minutes after the investigated materials (Scotchbond Multi-Purpose Dental Adhesive System or Prime & Bond 2.1) were administered on dentin as recommended by the manufacturer. In control rats (saline administration), the vessel diameter was stable during the experiment. In the presence of acetone-free bondmaterial (Scotchbond), the vessel diameter was increased during the experimental period in relation to the baseline (12.15+/-2.85%; 16.36+/-2.39%; 14.16+/-3.48%; 12.12+/-3.72%). In the presence of acetone-containing bondmaterial (Prime & Bond 2.1), a similar result was observed (10.56+/-2.27%; 16.13+/-2.94%; 17.88+/-2.54%; 14.54+/-3.16%). The differences between the control values and those registered with test groups were significant (p<0.05; ANOVA). There was no significant difference among the test groups. The results of this study suggest that dental bond materials applied on a very thin layer of dentin may affect the blood supply to the dental pulp. However, no stasis or prestasis has been detected, indicating a possible reversible effect. The authors could not show any statistical difference between the vasodilatation caused by the acetone-containing and the acetone-free bond material.

[Acute effect of calcium hydroxide-containing material in the rat's dental pulp microcirculation]. / Kálciumhidroxid-tartalmú pulpasapkázó anyag akut hatása patkányfogak pulpális keringésére.

Experimental stimulation and clinical procedures applied on the crown of the tooth cause vascular reaction in the dental pulp. Laser-Doppler flowmetry is a good method for determining the blood flow of the dental pulp. The aim of these experiments was to study the acute effect of a calcium hydroxide-containing pulp-capping material (Dycal, DeTrey) on blood flow of the dental pulp after the application into a deep test-cavity. Two groups of male Sprague-Dawley rats (308 g +/- 50 S.E.) were used: control- and test-group, n = 10. A standardised deep class five cavity was prepared in the left lower incisor of each rat. Laser-Doppler flowmeter was used to measure the vascular reaction of the pulp. The levels of blood flow were recorded prior to (0 min.) and after the application (1, 5, 15, 30, 60 min.) of Dycal. Results were evaluated with one-way ANOVA. Significantly higher pulpal blood flow was found only in the first minute after the application of Dycal. In any other time no significant difference was found between the results before and after (5, 15, 30, 60 min.) the application in test- and control-group.

[Effect of water storage and intrapulpal pressure on microleakage of three restorative materials]. / Nedvesség, valamint a szimulált intrapulpalis nyomás hatása az esztétikus tömóanyagok széli záródására.

Three different restorative materials, Z100 composite, F2000 compomer and Vitremer glass ionomer cement are currently proposed for Class V restorations. The aim of this in vitro study was to evaluate the influence of water storage and the simulated intrapulpal pressure (sIP) on the quality of the margins of class V restorations located both in enamel and dentin. The water resorption of restorative materials containing hydrophilic groups (compomers and glass ionomer cements) can favourably modify the marginal sealing ability by hydroscopic expansion. The influence of the sIP was specific to the material. While F2000 compomer and Vitremer glass ionomer cement were un-influenced by sIP, with Z100 composite a significant difference could be observed. It was concluded that F2000 compomer and Vitremer glass ionomer cement showed significantly less microleakage, which means a better marginal sealing ability than Z100 composite.

In vivo examination of the Scotchbond Multi-Purpose Dental Adhesive System in rat (vitalmicroscopic study).

No data are available on the direct acute vascular effect of dental bonding materials on the dental pulp. This study investigated the effects of the components of a composite resin-bonding system on pulpal vascular diameter. Three groups of 10 male Sprague-Dawley rats (weighing 330 +/- 51 g) were used for this investigation. The first lower incisor of the rats was prepared for vitalmicroscopy. Changes in vessel diameter were recorded prior to, and at 5, 15, 30 and 60 minutes after the bonding agents (with/without etching) or saline (control) were administered on dentin as recommended by the manufacturer. In control rats, the vessel diameter was elevated slightly (2.96 +/- 4.08%) during the whole experiment. However, in the presence of bonding materials, an enhancement of 12.58 +/- 7.1% without etching and 13.11 +/- 8.6% with acid etching was registered as the increase in vascular diameter. There were significant (p < 0.05) differences between the control group and those treated with bonding agent components. Results suggested that resin composite bonding agents applied to a thin layer of dentin have an acute vasodilating effect on the dental pulp. The clinical significance of this vascular alteration in the dental pulp requires further study.

[Comparison of the effect of acetone-containing and acetone-less bonding materials on dental pulp blood vessels in rats]. / Aceton és nem aceton tartalmú bondanyagok hatásának összehasonlítása patkányfogak pulpális erein.

No data are available on the direct acute vascular effect of dental bond materials in the dental pulp. The purpose of the present study was to investigate the effect of composite resin bonding systems on the pulpal vascular diameter. Three groups of male Sprague-Dawley rats (weighing 300-490 g), each of 10 animals were used for this investigation. The left lower incisor of the rats was prepared for vitalmicroscopy. Changes in vessel diameter were recorded prior to; and 5, 15, 30, 60 minutes after the application of saline (control) or the bonding agents (test1: acetone containing--/Prime/Bond2.1, DeTrey/; test2: acetone free /Scotchbond Multi-Purpose Adhesive System, 3M/ bond material) on pulpal dentin as recommended by the manufacturer. In control rats, the vessel diameter was stable during the experiment. However, in the presence of bonding materials an enhancement was registered in vascular diameter (p < 0.05). The bond materials applied directly onto a very thin layer of dentin show acute vasodilating effect on the rat pulpal microvessels, but no stasis or prestasis has been detected, indicating a possible reversible effect. We could not show any statistical difference between the vasodilatation caused by the acetone containing and the acetone free bonding material.