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Statement of problem The bonding and biological properties of currently used luting/cementing materials need to be improved. 4-Acryloyloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butylborane (4-META/MMA-TBB) resin is primarily used for splinting mobile teeth or treating fractured teeth. It undergoes moisture-resistant polymerization and bonds strongly to dentin and metals. Purpose The purpose of this in vitro study was to compare the biological and biochemical properties META/MMA-TBB resin with those of conventional polymethyl methacrylate (PMMA)-MMA resin and other currently used luting materials in order to determine whether it may be a viable dental luting agent. Material and methods The degree of polymerization of 4-META/MMA-TBB resin, PMMA-MMA autopolymerizing resin, 10-methacryloyloxydecyl dihydrogen phosphate-dimethacrylate (MDP-DMA) adhesive resin, and a glass ionomer cement was measured by Fourier-transformed infrared spectroscopy. Free radical production during setting was evaluated by electron spin resonance (ESR) spectroscopy. Rat dental pulp cells cultured on these materials were examined for cell viability, attachment, proliferation, and functional phenotype. Results The degree of polymerization of 4-META/MMA-TBB resin was 82% thirty minutes after preparation, compared to 66% for PMMA-MMA autopolymerizing resin. ESR spectroscopy revealed free radical production from 4-META/MMA-TBB resin and glass ionomer cement was equivalent 24 hours after preparation, with no spike in radical generation observed. In contrast, free radical production from PMMA-MMA and MDP-DMA adhesive resins was rapid and sustained and 10 to 20 times greater than that from 4-META/MMA-TBB. The percentage of viable dental pulp cells 24 hours after seeding was considerably higher on MDP-DMA and 4-META/MMA-TBB resin than on glass ionomer cement. Cell number, proliferation, and alkaline phosphatase activity were highest on 4-META/MMA-TBB resin and lowest on the glass ionomer cement. Conclusions 4-META/MMA-TBB resin is at least as biocompatible, and perhaps even more biocompatible, than other current luting materials, with fast, favorable, and nontoxic polymerization properties. Further in vivo and human studies of 4-META/MMA-TBB resin as a dental luting agent are warranted. [ABSTRACT FROM AUTHOR]

Abstract: The role of nanofeatured titanium surfaces in a number of aspects of in vivo bone–implant integration, and, in particular, their potential advantages over microfeatured titanium surfaces, as well as their specific contribution to osteoconductivity, is largely unknown. This study reports the creation of a unique nanobimorphic titanium surface comprised of nanotrabecular and nanotuft-like structures and determines how the addition of this nanofeature to a microroughened surface affects bone–implant integration. Machined surfaces without microroughness, sandblasted microroughened surfaces, and micro–nano hybrid surfaces created by sandblasting and alkali and heat treatment of Ti–15Mo–5Zr–3Al alloy were subjected to biomechanical, interfacial and histological analyses in a rat model. The presence of microroughness enabled accelerated establishment of biomechanical implant fixation in the early stages of healing compared to the non-microroughened surfaces; however, it did not increase the implant fixation at the late stages of healing. The addition of nanobimorphic features to the microroughened surfaces further increased the implant fixation by as much as 60–100% over the healing time. Bone area within 50μm of the implant surface, but not beyond this distance, was significantly increased by the presence of nanobimorphic features. Although the percentage of bone–implant contact was also significantly increased by the addition of nanobimorphic features, the greatest improvement was found in the soft tissue intervention between the bone and the implant, which was reduced from >30% to <5%. Mineralized tissue densely deposited with calcium-binding globular proteins was observed in an extensive area of nanobimorphic surfaces after biomechanical testing. This study clearly demonstrates the nanofeature-enhanced osteoconductivity of titanium by an alkali- and heat-treated nanobimorphic surface compared to that by microfeatured surfaces, which results not only in an acceleration but also an improvement of bone–implant integration. The identified biological parameters that successfully detect the advantages of nanofeatures over microfeatures will be useful in evaluating new implant surfaces in future studies. [Copyright &y& Elsevier]