Individualized wedge.

The preparation of an individualized wedge in the gingival embrasure before cavity preparation using photo-cured resin permits rehabilitation of the interproximal space and the original contact point position. Because the individualized wedge completely fills the embrasure, the adaptation to the gingival and proximal walls of the molar to be restored is perfect, avoiding any overextension of obturation material during insertion. Furthermore, the original position of the contact point is preserved.

A comparative study of apical leakage of Endomethasone, Top Seal, and Roeko Seal sealer cements.

A comparison was made of the apical leakage of three sealers. Fifty single-root human teeth were randomly divided into 5 groups (n = 10; 3 experimental and 2 control). The teeth of the positive-control and experimental groups were instrumented with K-type files to size 45. The experimental groups were obturated by laterally-vertically, condensed gutta-percha with Endomethasone, Top Seal, or RSA sealer cements. The positive-control group was nonobturated and the negative-control group was noninstrumented. The root surfaces were then coated with nail varnish (except the apex in the experimental groups) and immersed in black ink (for 1 week at 37 degrees C). The statistical evaluation of the results obtained by clearing and cross-section techniques showed no significant differences between sealers. Leakage, as determined by the clearing technique, was significantly greater than that quantified by cross-section analysis.

The effect of various surface treatments and bonding agents on the repaired strength of heat-treated composites.

STATEMENT OF PROBLEM: Some clinical situations may require the repair of a secondary polymerized or aged composite. The higher indirect resin conversion rate may prove to be a disadvantage if a repair procedure based on covalent bonding from unreacted methacrylate groups is attempted. PURPOSE: This study evaluated the effectiveness of different combinations of surface treatments and 2 bonding agents used to enhance heat-polymerized and aged composite repairs. MATERIAL AND METHODS: Ninety Herculite XRV and 90 Heliomolar Radiopaque specimens were prepared and then postpolymerized and stored for 4 weeks. All composites were subjected to 1 of 9 treatment regimens that involved adding fresh composite onto a corresponding postpolymerized composite (Herculite/Herculite or Heliomolar/Heliomolar). The surfaces were treated with different combinations of air abrasion, phosphoric acid, hydrofluoric acid, acetone, Special Bond II, Heliobond, and Prime & Bond 2.0. RESULTS: Surface treatment with air abrasion resulted in the strongest repairs; surface treatment with phosphoric acid resulted in the weakest repairs. CONCLUSION: The use of air abrasion and Prime & Bond 2.0 adhesive consistently improved the shear bond strength for both composites tested.

Amelogenesis imperfecta: diagnosis and resolution of a case with hypoplasia and hypocalcification of enamel, dental agenesis, and skeletal open bite.

A case of amelogenesis imperfecta with hypoplasia, hypocalcification of the enamel, congenital absence of teeth 12 and 22, delayed eruption of tooth 23, edge-to-edge incisal relationship, open bite, and bilateral posterior cross bite at the level of the first and second premolars is presented. Lateral skull teleradiography indicated a Class III skeletal pattern of maxillary origin associated with a dolichofacial pattern with multiple indicators of facial hyperdivergence. The patient presented a major esthetic abnormality of the face and required orthodontic treatment prior to a prosthetic solution with full-coverage metal-ceramic crowns in both the maxilla and the mandible. The diagnosis of cases such as this one and the therapeutic implications from an orthodontic and prosthetic standpoint are reported.

[The area of dentinal diffusion at the time of the manual preparation of root canals]. / Aire de diffusion dentinaire lors de la préparation manuelle des conduits radiculaires.

In this current piece of work we study the area of dentinal diffusion obtained with various irrigating agents which eliminate the smear layer: critic acid at concentrations of 10, 25 and 50%, 15% ethylene-diamino-tetraacetic acid (EDTA), and REDTA (compound of EDTA). All the agents proved their efficiency in eliminating the smear layer, which was corroborated by use of the sweep electron microscope and objectified using computerized image analysis, thus obtaining different diffusion areas with the various irrigating solutions used.

[Mechanical instrumentation of the root canals. A study using SEM and computerized image analysis]. / Instrumentation mécanique des conduits radiculaires. Une étude à l'aide du M.E.B. et analyse informatisée d'image.

The effectiveness of ultrasonic and sonic instrumentation in eliminating the smear layer from instrumented root channels. The results were examined with S.E.M. and the effective areas of dental diffusion were calculated using the computerized image analyzer. The agents used: citric acid at concentrations of 10, 25 and 50% as well as 15% EDTA, proved their efficiency with both types of mechanical instrumentation. However, the area of diffusion found was always greater using the ultrasonic instrumentation technique as opposed to the sonic instrumentation technique. 1, 2.5 and 5.25% sodium hypochlorite, as well as 10 volume hydrogen peroxide were not effective in eliminating the smear layer using both types of instrumentation.

[Bonding of glass ionomer cement to dentin. An in vitro study]. / La unión del cemento de vidrio ionómero a la dentina. Un estudio "in vitro".

It's been studied "in vitro" the influence of the "Smear Layer" on the cement adhesión of the glass ionomer to the dentin. Using phosphoric acid at 37% and poliacrylic in the dentin during short periods of time, the adhesion between the cement and the dentin is improved because the Smear Layer is removed totally in the case of phosphoric acid and partially in the case of polyacrylic acid.

[Optical and scanning electron microscope study of gingival microleakage in Class II composite restorations]. / Estudio con microscopia optica y electrónica de barrido de la microfiltración gingival en restauraciones de Clase II con composites.

It has been studied the gingival microleakage and the polymerization contraction gap in composites class II restorations. The influence of two different composites, a microparticle [Heliomolar (Vivadent)] and a high filled one [P-50 (3M)], has been compared with different adhesion systems: a) gingival enamel acid-etch technique. b) Dentinal adhesives [Gluma (Bayer) and Scotchbond 2 (3M)]. c) A adhesive varnish [Dentin Protector (Vivadent)]. The gingival microleakage is only prevented when a microparticle composite [Heliomolar (Vivadent)] and a adhesive varnish [Dentin Protector (Vivadent)] are used together.

[Compression resistance in premolars with OM cavities and palatally excavated cusps when obturated]. / Resistencia a la compresión en premolares con cavidades OM y con cuspide palatina socavada, al obturarlos.

Along this work, we study the salvage of resistance to pression of teeth with OM cavities and with an excavated top of the palate, when we obstruct it. We use composed resin or glass cement to fill up the excavated top in order to recover the outline of the OM cavity and we obstruct it with composed resin or combining glass cement with composed resin. Because any significant difference has been found between both kind of obstruction.

[Resistance recovery of prepared teeth obturated with different materials]. / Recuperación de resistencia del diente cavitado, al obturarlo con distintos materiales.

We have compared the endurance recuperation to the fracture of class II cavities, OM and MOD, filled with amalgam or composite resin. The composite resin recuperates the tooth endurance in the MOD cavities and in the OM cavities. The teeth with small OM cavities filled with amalgam recuperate their endurance to the original compression but the teeth with MOD cavities filled with this material don't recuperate it.