RESUMO
How to achieve the esthetic results with the restoration in anterior teeth is key aims which both of dentists and patients concern about now. Previously, the shape, color and texture of the teeth, i.e. "white esthetics" , were main objectives that prosthodontists want to achieve. The development of dental materials has played a key role in this field. More and more, the prosthodontist has realized that the healthy soft tissue is also very important for the final esthetic results. The healthy periodontal tissue is not only the basis for the longevity of restoration, but also the basis of esthetic results. The shape, color and texture of soft tissue, the mesial and distal gingival papilla, the margin and symmetry of the gingival, i.e. "pink esthetics" , have ultimate relationship with final esthetic results. The objective of the article is to introduce the common pink esthetic defects for the restorations in anterior teeth, the treatment protocol and methods to improve pink esthetic results.
RESUMO
By removing a part of the structure, the tooth preparation provides restorative space, bonding surface, and finish line for various restorations on abutment. Preparation technique plays critical role in achieving the optimal result of tooth preparation. With successful application of microscope in endodontics for >30 years, there is a full expectation of microscopic dentistry. However, as relatively little progress has been made in the application of microscopic dentistry in prosthodontics, the following assumptions have been proposed: Is it suitable to choose the tooth preparation technique under the naked eye in the microscopic vision? Is there a more accurate preparation technology intended for the microscope? To obtain long-term stable therapeutic effects, is it much easier to achieve maximum tooth preservation and retinal protection and maintain periodontal tissue and oral function health under microscopic vision? Whether the microscopic prosthodontics is a gimmick or a breakthrough in obtaining an ideal tooth preparation should be resolved in microscopic tooth preparation. This article attempts to illustrate the concept, core elements, and indications of microscopic minimally invasive tooth preparation, physiological basis of dental pulp, periodontium and functions involved in tool preparation, position ergonomics and visual basis for dentists, comparison of tooth preparation by naked eyes and a microscope, and comparison of different designs of microscopic minimally invasive tooth preparation techniques. Furthermore, a clinical protocol for microscopic minimally invasive tooth preparation based on target restorative space guide plate has been put forward and new insights on the quantity and shape of microscopic minimally invasive tooth preparation has been provided.
RESUMO
Objective: To construct an antibacterial peptide controlled release coating for percutaneous implant and to study its release and antibacterial properties. Methods: TiO2 nanotube specimens were prepared by anodizing. PDLLA was used as the retarder and HHC-36 as the antibacterial peptide, PDLLA-HHC-36 were loaded on TiO2 nanotube surface by solvent-casting technology. The surface form of the specimens was observed under SEM. Sustained release was analyzed by the release curves and the antibacterial effect was examined with inhibition zone test. Results: TiO2 nanotube specimens with 80-120 nm diameter were fabricated, the drug coating was observed under SEM. The drug loaded specimens showed 15 days sustained release in vitro and inhibition zone about 15 mm in diameter was found in the test for at least 10 days. Conclusion: TiO2 nanotube specimens with PDLLA-HHC-36 controlled release coating has sustained-release and antibacterial properties.
RESUMO
Objective@#To investigate the sagittal root position and apical bone height of the maxillary anterior teeth in order to provide anatomical information for immediate implant placement in the esthetic region.@*Methods@#Cone-beam CT (CBCT) data from 300 randomly selected patients who met the inclusion criteria were included in this study. After three-dimensional reconstruction, the sagittal plane (the sagittal plane through the long axis of the tooth) was determined. The positions and angulations of the tooth roots were classified with reference to the alveolar process. By comparing the buccal and palatal bone thickness at the mid-root level, the toot positions with reference to the mid-alveolar line were defined and classified as follows, type B (closer to the buccal alveolar surface), type M (midway between the buccal and palatal alveolar surface) and type P (closer to the palatal alveolar surface). By comparing the angulations of the alveolar process with the long axis of the roots, the angulations were classified as follows, type 1 (root apex angulated toward the palatal side or parallel to the alveolus), type 2 (root apex angulated toward the buccal side with the long axis passing posterior to point A) and type 3 (root apex angulated toward the buccal side with the long axis passing anterior to point A). The frequency of each category was counted and the apical bone height was measured. The subjects were divided into three age groups, 19-30 years, 31-50 years and 51-75 years.@*Results@#The overall mean apical bone height of the healthy maxillary central incisors was (9.2±3.0) mm, the lateral incisors was (10.0±2.9) mm and the canine was (8.1±3.1) mm. There was no significant difference in the height of apical bone between central incisors and lateral incisors (P>0.05). There was no significant difference in the height of apical bone between male and female (P>0.05). The height of apical bone in group 31-50 years and 51-75 years were greater than that in group 19-30 years (P<0.05), respectively. The proportion of the maxillary anterior teeth type B, M, P was 98.5% (1 774/1 800), 0.3% (5/1 800) and 1.2% (21/1 800) respectively. The proportion of type 1, 2, 3 was 2.6% (46/1 800), 58.6% (1 055/1 800) and 38.8% (699/1 800) respectively.@*Conclusions@#There was enough apical bone height in the area of maxillary anterior teeth, but the majority of roots positioned more buccally.
RESUMO
?Objective: To develop the electroplated diamond grinding discs and burrs used on CEREC II CAD/CAM system. Methods: Using electroplated technology, the diamond grain and nickel were deposited together on the surface of stainless steel discs and burrs and then a composite electroplated diamond layer was formed, which was the method that diamond coated grinding discs and burrs were made. The experimental grinding discs and burrs were used to mill porcelain blocks on CEREC II CAD/CAM system and were compared with CEREC discs and burrs. Results: There were no significant differences between the experimental samples and CEREC samples on milling property and durability. Conclusion: The electroplated technology is simple and feasible. The diamond coated grinding discs and burrs made with this method can be used on CEREC II CAD/CAM system, but the further investigation is also needed.