Indian Journal of Dental Research最新文献

Aim: The objective of this in-vitro study was to assess the cytotoxicity and alkaline phosphatase (ALP) activity of curcumin and aloin extracted from Curcuma longa and Aloe vera , and mineral trioxide aggregate (MTA) on human dental pulp stem cells.

Methods: Human dental pulp stem cells (Lonza Group, Switzerland), curcumin (Sigma-Aldrich, USA), aloin (Sigma-Aldrich, USA), and ProRoot MTA (Dentsply, USA) were used in the study. 2.5-6.75-12.5-25-50 μg/ml of curcumin and aloin, 25%-50%-75%-100% of MTA were prepared; pulp cells unincubated with a material were assessed as controls. Cytotoxicity of all doses/concentrations of materials was analysed on days of 1, 2, 3, and 7 by WST-1 test. 2.5-6.75 μg/ml of curcumin and aloin, 25%-50% of MTA incubated with cells for 7-14 days were evaluated for ALP activity by ELISA test. Data was statistically analysed by One Way ANOVA, Tukey, and Sidak tests at GraphPad Prism 6.

Results: The findings have shown that 2.5 μg/ml of curcumin, all doses of aloin, 25% and 50% of MTA increased cell proliferation significantly on day 1 ( P < 0.05). Curcumin, aloin, and MTA decreased the cell viability as dose/concentration and exposure time increased. All materials have shown no significant increases in ALP activity ( P > 0.05) on 7 and 14 days.

Conclusion: Data of this study revealed that 2.5 - 6.75 μg/ml of curcumin/aloin, 25%-50% of MTA have promoted cell viability and proliferation of human dental pulp cells; and none of the materials have significantly increased the ALP activity at 7-14 days.

Aim: To determine stresses generated in the posterior teeth region by two different self-ligating systems, 3M Unitek SmartClip and Damon Q Self-ligating brackets, using the finite element method (FEM).

Methodology: Computed tomography (CT) scan of maxilla was taken using Mimics software, and the Dicom data were imported into Hypermesh 13.0 software to convert it into a geometric model and then into FEM. Physical models of both the brackets were constructed and positioned on the teeth. Post archwire modeling, contact is defined between the bracket slot and 0.014" NiTi arch wire. The final assembled model was exported to ANSYS 12.1 for analysis, and 60 grams of load was applied at the ends of the arch wire.

Results: On using 0.014" CuNiTi in both the bracket systems, stresses generated on the root surface were found to be maximum on the first molar region, followed by the first premolar, second molar, canine, and second premolar regions. Comparison between the two bracket systems showed differences in the stresses generated, where higher stresses were generated at all regions in the Damon Q bracket system, except the inter-second premolar region.

Conclusion: Maximum stresses were observed with the 3M Unitek SmartClip bracket system at the second premolar cervical region when compared to the Damon Q system. In both the cortical bone and cancellous bone, maximum stresses were observed at the second premolar cervical in the Damon Q bracket system region.

Introduction: During orthodontic treatment, temporary anchoring devices (TADs) are used to restrain tooth movement. They are a relatively recent addition to the dental toolkit.

Aim: As TADs have limitations, Dr. Eric Lieu of Taiwan developed Infra Zygomatic Crest (IZC) screws which are placed between the maxillary second premolar at the bony crest.

Treatment planning: The goal of this case study is to emphasize the value of anatomy, site selection, and IZC retrieval in the event of an accident. Cone beam computed tomography was used as a diagnostic tool for the precise location of the displaced IZC and immediate surgical retrieval was done under local anesthesia from the infratemporal space to prevent further complications.

Takeaway lessons: Orthodontists knowledge of soft tissue and hard tissue anatomy and precise positioning is crucial for successful TAD implantation.