An Update on the Use of Lasers in Prosthodontics.

Lasers are employed in all fields of modern dentistry nowadays, including both surgical and non-surgical dental procedures. Prosthodontics, a branch of dentistry, has also embraced lasers as an invaluable addition to conventional methodologies. This helps improve the standard of care for patients and dentists due to its precise excision, quick healing, and enhanced tissue response after surgeries. In prosthodontics, the most commonly used lasers are carbon dioxide, argon, and yttrium-aluminum-garnet (YAG) lasers. Many reviews have been published in the literature regarding the use of lasers in dentistry; however, reviews on the use of lasers in the field of prosthodontics are limited. This review aims to explain the diverse applications and advancements of lasers in prosthodontics. Furthermore, it will highlight the integration of lasers in diagnostic protocols, treatment modalities, and the fabrication of prosthetic restorations.

Assessing the effect of Artemisia sieberi extracts on surface roughness and candida growth of digitally processed denture acrylic materials.

BACKGROUND: Denture stomatitis, frequently encountered, is generally addressed symptomatically, with limited exploration of preventive approaches involving antifungal medicinal plants. OBJECTIVE: This study assessed the impact of Artemisia sieberi extracts on the candida growth of conventional and digitally processed acrylic materials. METHOD: Thirty acrylic resin discs (3 mm thickness × 10 mm diameter) were prepared by conventional or CAD/CAM technology (milling and 3D printing). The resin discs were exposed to simulated brushing, thermocycling, and immersion in Artemisia sieberi extract for 8 hours. The surface roughness of the discs was assessed at baseline and after immersion in Artemisia sieberi extract. Candida growth was quantified through colony-forming units (CFU/mL). Data was analyzed using SPSS v.22 (α⩽ 0.05). RESULTS: Irrespective of the material type, the post-immersion surface roughness was significantly higher compared to pre-immersion values (p< 0.05). Candida growth was significantly higher in conventional acrylic materials than digitally fabricated acrylics (p< 0.05). At × 3, Ra and CFU were found to be moderately positive and non-significantly correlated (R= 0.664, p= 0.149). At × 4, Ra and CFU were found to be weak positive and non-significantly correlated (R= 0.344, p= 0.503). CONCLUSION: Artemisia sieberi extracts had a notable impact on digitally fabricated denture acrylics, reducing candida albicans growth compared to conventional heat-cured acrylic. This suggests a potential role for these extracts in improving denture hygiene and preventing denture stomatitis, particularly in the context of digitally fabricated dentures.

Control of craniofacial development by the collagen receptor, discoidin domain receptor 2.

Development of the craniofacial skeleton requires interactions between progenitor cells and the collagen-rich extracellular matrix (ECM). The mediators of these interactions are not well-defined. Mutations in the discoidin domain receptor 2 gene (DDR2), which encodes a non-integrin collagen receptor, are associated with human craniofacial abnormalities, such as midface hypoplasia and open fontanels. However, the exact role of this gene in craniofacial morphogenesis is not known. As will be shown, Ddr2-deficient mice exhibit defects in craniofacial bones including impaired calvarial growth and frontal suture formation, cranial base hypoplasia due to aberrant chondrogenesis and delayed ossification at growth plate synchondroses. These defects were associated with abnormal collagen fibril organization, chondrocyte proliferation and polarization. As established by localization and lineage-tracing studies, Ddr2 is expressed in progenitor cell-enriched craniofacial regions including sutures and synchondrosis resting zone cartilage, overlapping with GLI1 + cells, and contributing to chondrogenic and osteogenic lineages during skull growth. Tissue-specific knockouts further established the requirement for Ddr2 in GLI +skeletal progenitors and chondrocytes. These studies establish a cellular basis for regulation of craniofacial morphogenesis by this understudied collagen receptor and suggest that DDR2 is necessary for proper collagen organization, chondrocyte proliferation, and orientation.

We each have unique facial features that are key to our identities. These features are inherited, but the mechanisms are poorly understood. People with the genetic disease spondylo-meta-epiphyseal dysplasia, or SMED, have characteristic facial and skull abnormalities including a flattened face and shortened skull. SMED is associated with mutations that inactivate the gene encoding a protein called discoidin domain receptor 2 (DDR2), which is a receptor for collagen. Collagen is the major structural protein in the human body, supporting the structure of cells and tissues. It also controls cell behaviors including growth, migration and differentiation, and it helps form tissues such as cartilage or bone. At least some of the effects of collagen on cells depend on its interaction with DDR2. Since the facial and skull abnormalities in mice with mutations that stop DDR2 from working correctly resemble those of SMED patients, these mice can be used to understand the cellular basis for this disease, as well as the role of DDR2 in the embryonic development of the face and skull. Therefore, Mohamed et al. set out to understand how loss of DDR2 causes the characteristic facial and skull defects associated with SMED. Mohamed et al. used mice that had been genetically modified so that DDR2 could be inactivated in skeletal progenitor cells, cartilage cells and bone cells (osteoblasts). Examining these mice, they found that the shortened skulls and flat face characteristic of mice lacking DDR2 are due to bones at the skull base failing to elongate correctly due to defects in the growth centers that depend on cartilage. Mohamed et al. also discovered that the cells that normally produce DDR2 are the progenitors of cartilage and bone-forming cells, which partly explains why lacking this protein leads to issues in growth of these tissues. In addition to shedding light on the causes of SMED, Mohamed et al.'s results also provide general insights into the mechanisms controlling the formation of facial and skull bones that depend on interactions between cells and collagen. This information may help explain how other abnormalities in the face and skull emerge, and provide a basis for how the shape of the skull has changed during human evolution. In the future, it may be possible to manipulate the activity of DDR2 to correct skull defects.

Dental students' academic performance before and after the Covid-19 pandemic: A retrospective analysis.

Delivering quality education to students with fair assessment strategies is a key indicator of an excellent educational institution. The present study explored the impact of the COVID-19 pandemic on the academic performance of dental students in terms of the evaluations/grades awarded to them before and during the pandemic. The targeted groups were dental students, studying in the third year of 2018-2019 and 2020-2021 academic years. The sample size included all male and female students who enrolled and completed the following courses: pre-clinical fixed prosthodontics (SDS333), pre-clinical removal prosthodontics (SDS323), clinical operative dentistry-1 (RDS313), and pre-clinical endodontics (RDS323). Evaluations for students who did not complete the requirements were not included in the statistical analysis. Paired sample statistics were used for comparisons between the different groups at p < 0.05. Results revealed statistically significant differences (p ≤ 0.05) for all the course pairs. It was found that students' grades for all the courses during the pandemic year were higher compared to the grades before the pandemic. While female students demonstrated the highest mean difference (6.13) before and during the pandemic year for RDS323, males demonstrated the highest mean difference (8.14) for SDS323. However, both male and female students demonstrated the lowest mean difference (0.25 and 2.03, respectively) for SDS333. The grades were higher during the COVID-19 pandemic. Overall, female students achieved higher grades than male students.

Salvadora persica's Biological Properties and Applications in Different Dental Specialties: A Narrative Review.

Salvadora persica is a tree that belongs to the salvadorecea family. It is also known as Miswak, which is a popular natural toothbrush that was used centuries ago in oral hygiene by Muslims in all parts of the world, especially in the Middle East. Numerous researchers highlighted the biological activity of this plant in medicine, dentistry, and pharmacology. The purpose of this article is to narratively review the biological properties of Salvadora persica. In addition, it expresses variant applications of this herb in different dental specialties. Materials and Methods. The search of the literature was based on PubMed, MEDLINE, and Google Scholar using keywords: Salvadora persica, S. persica, Miswak, Dentistry, and Dental. All relevant articles were reviewed to check if they would fit within the scope of this review, and then, the information was extracted. Results. Multiple biological effects of S. persica have been reported including antibacterial, antiviral, antifungal, antibiofilm, antioxidant, and even antiulcer effects. Dental effects were discussed and presented. Conclusion. The wide biological range of Salvadora persica's effects is promising for dental and nondental fields and allows for an expanded clinical application that has otherwise not been discussed in the literature.

The collagen receptor, discoidin domain receptor 2, functions in Gli1-positive skeletal progenitors and chondrocytes to control bone development.

Discoidin Domain Receptor 2 (DDR2) is a collagen-activated receptor kinase that, together with integrins, is required for cells to respond to the extracellular matrix. Ddr2 loss-of-function mutations in humans and mice cause severe defects in skeletal growth and development. However, the cellular functions of Ddr2 in bone are not understood. Expression and lineage analysis showed selective expression of Ddr2 at early stages of bone formation in the resting zone and proliferating chondrocytes and periosteum. Consistent with these findings, Ddr2+ cells could differentiate into hypertrophic chondrocytes, osteoblasts, and osteocytes and showed a high degree of colocalization with the skeletal progenitor marker, Gli1. A conditional deletion approach showed a requirement for Ddr2 in Gli1-positive skeletal progenitors and chondrocytes but not mature osteoblasts. Furthermore, Ddr2 knockout in limb bud chondroprogenitors or purified marrow-derived skeletal progenitors inhibited chondrogenic or osteogenic differentiation, respectively. This work establishes a cell-autonomous function for Ddr2 in skeletal progenitors and cartilage and emphasizes the critical role of this collagen receptor in bone development.

Clinical, bacterial, and inflammatory outcomes of indocyanine green-mediated photodynamic therapy for treating periimplantitis among diabetic patients: A randomized controlled clinical trial.

Background This 6-months randomized controlled clinical trial aimed to assess the efficacy of indocyanine green mediated photodynamic therapy (ICG-PDT) as an adjunct to peri­implant manual debridement (PIMD) versus PIMD alone among Diabetes Mellitus (DM) patients in the treatment of peri­implantitis. Methods A total of 48 DM patients having 64 implants were treated with either ICG-PDT + PIMD (n = 35 implants) or PIMD alone (n = 29 implants). Clinical (probing depth [PD], bleeding on probing [BOP], and plaque index [PI]) and radiographic (peri­implant crestal bone loss [PCBL]) peri­implant variables were recorded. Bacterial species including Porphyromonas gingivalis and Treponema denticola were evaluated from peri­implant plaque biofilms. Levels of interleukin (IL)-1ß and IL-6 were assessed after the collection of peri­implant sulcular fluid. All the evaluations were carried out at baseline, 3- and 6-months. The significance level was set to p < 0.05. Results All clinical parameters significantly reduced within both treatment groups (P<0.05). Intra-group comparison indicates that there was statistically significant reduction in PD and suppuration for ICG-PDT group (P<0.05). There was a statistically significant difference in the BOP between ICG-PDT and PIMD groups at both follow-up periods (P<0.001). However, there was a significant difference for PD (P = 0.001), suppuration (P = 0.01), and PCBL (P = 0.04) on 6 months follow-up between ICG-PDT and PIMD groups, respectively. Only ICG-PDT showed a significant reduction in P. gingivalis and T. denticola on both 3 months and 6 months follow-up compared to baseline. PIMD showed a statistically significant reduction only on 3 months follow-up compared to baseline. This reduction was maintained for both the species when dental implants were treated with ICG-PDT. However, PIMD failed to maintain this reduction until 6 months. Only at 3 months assessment that both treatment groups showed statistically significant reduction in IL-1ß and IL-6 with no significant difference between the groups. Both biomarkers failed to maintain the reduction in both groups and significantly increased levels for IL-1ß was noted at 6 months follow up Conclusion Multiple application of indocyanine-green mediated photodynamic therapy resulted in improved clinical and microbial parameters among type 2 DM subjects in the treatment of peri­implantitis. This clinical trial was registered in the ClinicalTrials.gov Protocol Registration and Results System with registration record number: NCT04833569.