Ultrasonic sulcus penetration: a new approach for full crown preparations.

Newly developed ultrasonic diamond-coated tips (UDT) have been created for sulcus penetration and intracrevicular finish line preparation and polishing. One hundred forty-two freshly extracted premolars and molars were employed for a cutting efficiency test. Dentin surface roughness was analyzed with an optical profilometer and a scanning electron microscope.

Inflammatory and immunological aspects of dental pulp repair.

The repair of dental pulp by direct capping with calcium hydroxide or by implantation of bioactive extracellular matrix (ECM) molecules implies a cascade of four steps: a moderate inflammation, the commitment of adult reserve stem cells, their proliferation and terminal differentiation. The link between the initial inflammation and cell commitment is not yet well established but appears as a potential key factor in the reparative process. Either the release of cytokines due to inflammatory events activates resident stem (progenitor) cells, or inflammatory cells or pulp fibroblasts undergo a phenotypic conversion into osteoblast/odontoblast-like progenitors implicated in reparative dentin formation.

The impact of bioactive molecules to stimulate tooth repair and regeneration as part of restorative dentistry.

After implantation in the exposed pulp, some molecules of the den-tin extracellular matrix induce the formation of a reparative dentinal bridge in the coronal pulp. In some cases, total occlusion of the root canal also is observed. This is the case for bone sialoprotein, bone morphogenetic protein-7, Dentonin (a fragment from matrix extracellular phosphoglycoprotein), and two small amelogenin gene splice products (A+4 and A-4).

Bioactive molecules and the future of pulp therapy.

Direct capping of bioactive molecules or implantation of these molecules in the pulp may induce the formation of reparative dentin and coronal or radicular pulp mineralization. In this review, we summarize what is known and/or assumed on the biological mechanisms of these therapies. We report on the effects which were obtained experimentally in rat maxillary molars by implantation of Bone Sialoprotein (BSP)/collagen pellets and Specific Amelogenin Gene Splice Products [A+4] and [A-4]) adsorbed on agarose beads.

Differential repair responses in the coronal and radicular areas of the exposed rat molar pulp induced by recombinant human bone morphogenetic protein 7 (osteogenic protein 1).

Bone morphogenetic protein 7 (BMP 7), also termed osteogenic protein 1, a member of the transforming growth-factor superfamily, was examined for its efficacy in inducing reparative dentinogenesis in the exposed pulps of rat molars. To determine if the reaction was dose-dependent, collagen pellets containing 1, 3 or 10 microgram of recombinant BMP 7 were inserted in intentionally perforated pulps (10-12 pulps per group) in the deepest part of half-moon class V-like cavities cut in the mesial aspect of upper first molars. As controls, the collagen carrier (CC group) alone and calcium hydroxide (Ca group) were used as capping agents.