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The purpose of this study is to investigate the reparation of metal ceramic crowns with ceramic mass. 30 metal ceramic crowns which restore the upper first central incisor (2.1) were divided in three groups. Each group was repaired with a different ceramic material. Group 1- In Line (Ivoclar Vivadent) ceramic, the second group was repaired with D. Sign (Ivoclar Vivadent) and for the last group was used VMK. Master (Vita). All the repaired crowns were investigated through imagistic non-invasive methods. The metallic infrastructure of the samples was made from Ni-Cr alloy and the porcelain mass was Kiss (D. Sign). Defects were made on the buccal surface of each crown. The ceramic mass and the opaque were removed and the metallic infrastructure was exposed. Size defects has 3Ã?3mm and it is situated on incise and 1/3 medium buccal surface. The defect was made with a green grinding instrument under air-water cooling. All the samples were conditioned and repaired with ceramic mass. The reparations were investigated with two noninvasive imagistic methods Rx and Optical Coherence Tomography Time Domain in order to detect de reparation's defects. The investigation methods may spot the presence or absence defects localized at the interface between the two materials and those localized in the ceramic mass.

The present study is proposing to investigate through non-invasive techniques, the quality of repaired of all-ceramic crowns with ceramic material. 20 all-ceramic crowns made with IPS e.max Empress System. The ceramic component was removed with a grinding instrument from the buccal-incisal of each crown. The ceramic veneer was removed in order to simulate the fracture of the ceramic supra-structure. Defect's size was approximately 3Ã?3mm for all the specimens. In some cases the incisal margin was also removed. All the crowns were repaired with ceramic material VM7 (Vita) after the manufacturer's instructions. The repaired area was investigated through imagistic and also non-invasive techniques. The involved investigation systems are analyzing macroscopic and microscopic the repaired area. Optical Coherence Tomography Time Domain and X ray. Optical Coherence Tomography is an optical microscope which can scan the surface and deep layers of the investigated interface. X ray is useful in detecting macroscopic defects and gaps into the material mass. The quality of the repaired defects may be evaluated and some clinical indications can be made.

Fixed partial prostheses as integral ceramic, polymers, metal-ceramic or metal-polymers bridges are mainly used in the frontal part of the dental arch (especially the integral bridges). They have to satisfy high stress as well as esthetic requirements. The masticatory stress may induce fractures of the bridges. These may be triggered by initial materials defects or by alterations of the technological process. The fractures of these bridges lead to functional, esthetic and phonetic disturbances which finally render the prosthetic treatment inefficient. Dental interfaces represent one of the most significant aspects in the strength of the dental prostheses under the masticatory load. The purpose of this study is to evaluate the capability of optical coherence tomography (OCT) to characterize the dental prostheses interfaces. The materials used were several fixed partial prostheses integral ceramic, polymers, metal-ceramic and metal-polymers bridges. It is important to produce both C-scans and B-scans of the defects in order to differentiate morphological aspects of the bridge infrastructures. The material defects observed with OCT were investigated with micro-CT in order to prove their existence and positions. In conclusion, it is important to have a non invasive method to investigate dental prostheses interfaces before the insertion of prostheses in the oral cavity.

The purpose of this study is to present a non invasive method for the marginal adaptation evaluation in class V composite restorations. Standardized class V cavities prepared in human extracted teeth were filled with composite resin (Premise, Kerr). The specimens were thermocycled. The interfaces were examined by Optical Coherence Tomography (OCT) combined with confocal microscopy and fluorescence. The optical configuration uses two single mode directional couplers with a superluminiscent diode as the source at 1300 nm. The scanning procedure is similar to that used in any confocal microscope, where the fast scanning is en-face (line rate) and the depth scanning is much slower (at the frame rate). Gaps at the interfaces as well as on the inside of the composite resin were identified. OCT has numerous advantages that justify its in vivo and in vitro use compared to conventional techniques. One of the main concerns was the fact that at the adhesive layer site it was very hard to tell the adhesive apart from material defects. For this reason the adhesive was optimized in order to be more scattering. This way we could make a difference between the adhesive layer and the material defects that could lead to microleakages.

Standardized class V cavities, prepared in human extracted teeth, were filled with Premise (Kerr) composite. The specimens were thermo cycled. The interfaces were examined using a system employing two simultaneous imaging channels, an en-face Optical Coherence Tomography channel and a confocal microscopy channel. © 2009 SPIE-OSA.

The aim of this study was to analyze the quality of marginal adaptation and gap width of Empress veneers using en-face optical coherence tomography. The results prove the necessity of investigating the marginal adaptation after each veneer bonding process.

The present study evaluates the potential of en-face optical coherence tomography (OCT) as a possible noninvasive high resolution method for supplying necessary information on the material defects of dental prostheses and microleakage at prosthetic interfaces. Teeth are also imaged after several treatment methods to asses material defects and microleakage at the tooth-filling interface, and the presence or absence of apical microleakage, as well as to evaluate the quality of bracket bonding on dental hard tissue. C-scan and B-scan OCT images as well as confocal images are acquired from a large range of samples. Gaps between the dental interfaces and material defects are clearly exposed.

Despite good diagnosis and treatment planning, orthodontic treatment can fail if bonding fails. It is now common practice to address the aesthetic appearance of patients using aesthetic brackets instead of metal ones. Therefore, bonding aesthetic brackets has become an issue for orthodontists today. Orthodontic bonding is mainly achieved using composite resin but can also be performed with glass ionomer or resin cements. For improving the quality of bonding, the enamel is acid etched for 30 seconds with 38% phosphoric acid and then a bonding agent is applied. In our study we investigated and compared the quality of bonding between ceramic brackets, polymeric brackets and enamel, respectively using a new investigation method - OCT. The aim of our study was to evaluate the resin layer at the bracket base - tooth interface.