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Purpose: To evaluate a modified Bioglass (Formula #68 (MBF68) when used as a pulp capping agent., Materials and Methods: After exposure, the pulps were contaminated with saliva for 60s, rinsed, dried and treated with Consepsis, acting as a hemostatic and bactericidal agent. After drying the Consepsis, the MFB68, having been pre-mixed in sterile saline, was carefully deposited over the pulp exposure, covered with polycarboxylate cement and restored with the ProBond bonding resin system. A calcium hydroxide group was used as control., Results: There was no evidence of mummification, the incidence of properly positioned dentin bridge formation was higher and the incidence of extruded dentin bridge formation was reduced.

There are many skeptics who condemn pulp capping but like to keep an eye on the research progress being made. Considerable literature emphasizes the negative aspects of vital pulp therapy and discourages its practice. Some clinicians and investigators continue to condemn pulp capping therapy for the same reasons reported in the literature 80 years ago despite the advances made in pulp biology. Clinicians are well aware of the immediate and long-term success rates after root canal therapy, but are less certain of the success of pulp capping. A number of nagging questions plague clinicians, when confronted with the choice of treatment. The research data on pulp capping is at times inadequate, confusing, misleading or even incorrect and diminishes the confidence of the practitioner in performing pulp capping.

Purpose: To determine by means of a histopathological study in sub-human primates whether etching of an exposed pulp (the "Total Etch" technique) followed by capping with dentin bonding agents is a viable clinical treatment modality., Materials and Methods: In six sub-human primates, 147 Class V preparations were made for five experimental and two control groups. After exposing the pulps, the preparations were intentionally contaminated, rinsed, dried and then disinfected with a 2% chlorhexidine solution for 60 s. In the five experimental groups, the entire preparation including the exposed pulp was etched with a 35% phosphoric acid gel, which was rinsed after 20 s. This was followed by a second application of chlorhexidine. In Groups 1-3, All Bond 2, ProBond and Permagen A&B dentin bonding agents were applied as pulp capping materials. In Group 4, a light-cured calcium hydroxide was tested while Group 5 was treated with a chemically-cured calcium hydroxide. Groups 6 and 7, the controls, were also contaminated, rinsed, dried and disinfected. After the exposed pulps had been protected with a chemically-cured calcium hydroxide (Group 6) or a light-cured calcium hydroxide (Group 7) the preparations were etched and restored with a bonded resin composite. The effect of the above described treatments were evaluated at 5, 25 and 75 days. After sacrifice and routine histological preparation, histological sections were graded among other parameters for inflammatory response, bridge formation, maintenance of vitality, presence of dentin chips and evidence of microleakage microorganisms., Results: The 2% chlorhexidine applied immediately after exposure was an effective hemostatic agent. After subsequent etching, the hemostatic effectiveness was greatly reduced. Exposure size for all seven groups ranged from 0.13-1.55 mm. The average at 5, 25 and 75 days measured 0.74, 0.66 and 0.77 mm, respectively. In the five experimental groups, the 25- and 75-day groups had a total of 68 teeth of which 24 (35%) became non-vital and 23 (33%) teeth demonstrated bridge formation. In the three experimental groups using a bonding agent, the 25- and 75-day groups had a total of 40 teeth of which 18 (45%) became non-vital and 10 (25%) exhibited bridge formation. In the "No Etch" control groups, the 25- and 75-day groups had 28 teeth of which two (7%) became non-vital and 23 (82%) exhibited bridge formation. Microorganisms were found in a large percentage of all groups, although their numbers were few. However, they were present in vital and non-vital teeth, in the presence and absence of bridge formation and had no direct bearing on the success or failure of the pulp capping procedure.

Purpose: To determine the pulpal biocompatibility of Prisma Universal Bond 2 (PUB-2)., Materials and Methods: Class V preparations were made in eight subhuman monkeys to approximately 1 mm from the pulp. In Group 1, the enamel was etched, the primer was placed and dried, PUB 2 was painted, and Prisma-Fil inserted. In Goup 2, the cavity floor was covered with visible light-cured Dycal followed by the steps as in group 1. In Group 3, IRM was used as a negative control. In Group 4, MQ55 silicate cement was used as a positive control. The animals were sacrificed at 5, 25, and 60 days and the teeth processed for histological evaluation., Results: After 5 days, a mild reaction of little concern, which had dissipated in the 25- and 6-day groups, was observed. The material compared favorably to the negative control.

Several formulas of a resin-filled cement that successfully passed a series of laboratory tests were evaluated for their pulp reactions in primates. Their performance was compared to three controls: a positive control (silicate cement), a negative control (zinc oxide-eugenol) and a control group with the protection of calcium hydroxide. The chemical cure resin cement scored the lowest reactions for the 5-day evaluation. The intermediate and prolonged periods demonstrated no significant differences while average, acceptable responses were recorded. No resin cement formula scored as low as the negative control for the three time periods. Silicate cement, the positive control, scored the greatest inflammatory reaction of any material in the intermediate period, but this response was resolved after 60 days. When the resin cements were used with calcium hydroxide, the traditional reactions to calcium hydroxide were observed; an initial mild irritation that diminished with time and was completely resolved after 60 days. The resin cements, with or without the calcium hydroxide, compared favorably to the negative control IRM after 60 days. If the resin cements are appropriately applied, they are expected to be well tolerated by the human pulp. The microorganisms associated with microleakage (MLM) were minimal and there appeared to be no correlation between the MLM and pulp inflammation.

In this experiment, 64 crown preparations were made in four primates. Final impressions, die fabrication, wax patterns and castings were achieved using conventional established clinical and laboratory techniques. Vented and unvented crowns were cemented with a glass ionomer cement (GI) and a zinc phosphate cement (ZOP). Some preparations were protected with calcium hydroxide liquid. On the same animals, in teeth not used for crowns, Class V cavities were prepared and GI and ZOP inserted by means of a pressure technique imitating hydraulic pressure generated during crown cementation. After periods of 5 and 60 days, the animals were sacrificed, the jaws dissected, fixed in formalin and prepared for histological evaluation. Of the 64 cemented crowns, one was unaccounted for. Of the unvented crowns with GI (5 days), vented crowns with GI (60 days), unvented crowns with ZOP (60 days), Class V with ZOP (5 days) and GI (60 days) with a remaining dentin thickness (RDT) of less than 1 mm, inflammatory responses of greater than or equal to 1 degree (on a scale 1-4 degrees) were observed. The use of liquid calcium hydroxide reduced the intensity of the reactions, in particular when small RDTs were present. It can be concluded that when RDTs of 1 mm or more were present, the cements in all groups were non-toxic. When it is estimated that the RDT is less than or equal to 1 mm, the use of a calcium hydroxide liner is recommended. Placement of luting agents in Class V preparations with pressure resulted in reactions resembling crown cementation.(ABSTRACT TRUNCATED AT 250 WORDS)