Efficacy of laser in re-osseointegration of dental implants-a systematic review.

Despite their high success rates, peri-implantitis can affect the stability and function of dental implants. Various treatment modalities have been investigated for the treatment of peri-implantitis to achieve re-osseointegration. An electronic literature search was performed supplemented by a manual search to identify studies published until January 2022. Articles that evaluated re-osseointegration in peri-implantitis sites in animal models following laser therapy or antimicrobial photodynamic therapy (aPDT) were included. Case reports, case series, systematic reviews, and letters to the editor were excluded. Risk of bias and GRADE assessment were followed to evaluate the quality of the evidence. Six studies out of 26 articles identified on electronic search were included in this review. The studies included animal studies conducted on canine models. Four out of six studies reported a higher degree of re-osseointegration following treatment of implants with laser therapy. The findings suggest that laser decontamination shows potential in enhancing re-osseointegration, particularly with the Er: YAG laser, which effectively decontaminated implant surfaces. However, conflicting outcomes and limitations in the evidence quality warrant caution in drawing definitive conclusions. Based on the limited available evidence, laser therapy may show a higher degree of re-osseointegration of implants than mechanical debridement.

Effectiveness of haptic feedback devices in preclinical training of dental students-a systematic review.

BACKGROUND: Acquisition of psychomotor skills is of utmost importance for competent preclinical restorative dentistry. Recent advancements in haptic feedback technology have been incorporated into preclinical dental education to augment the conventional phantom head-based training. OBJECTIVE: This systematic review aims to assess the effectiveness of haptic feedback device, Simodont, in improving the skill development and learning outcomes of dental students during their preclinical training. MATERIALS AND METHODS: Electronic databases Web of Science, Scopus, PubMed were searched for relevant studies since inception up until March, 2023. Only English language studies that assessed the effectiveness of haptic feedback devices in preclinical dental education were included. We excluded studies that did not use Simodont as the haptic feedback device or did not involve preclinical restorative work. Study quality was assessed using the revised Cochrane risk of bias tool and ROBINS-I. The primary goal of the study is to evaluate the efficacy of Simodont as a complementary training modality for dentistry students. RESULTS: Results from 9 high-quality studies were analyzed and synthesized to evaluate the overall impact of haptic feedback devices on various aspects of preclinical training. The studies were conducted on 826 undergraduate dental students enrolled in various years of their training across dental colleges and universities in different parts of the world. A majority of studies showed some concerns regarding risk of bias. Haptic feedback devices added a new layer to Virtual Reality (VR) through the perception of touch and force feedback. It assisted junior dental students improve their psychomotor skills and movement skills. Instantaneous feedback on the students' performance helped enhance their self-assessment and correction, and also eliminated the subjectivity of evaluation. Data derived from virtual simulators helped stratify dental students and predict their clinical performance, providing an opportunity to tailor the learning process to meet individual diversity in students' expertise. CONCLUSION: Based on the limited evidence available, Simodont was effective in preclinical training of dental students, offering advantages such as unlimited reproducibility, objective evaluation of preparation by computer assessment, and cost reduction. And further studies are warranted to explore the incorporation of patient's oral environment simulation for better skill training.

Impact Strength of Various Types of Acrylic Resin: An In Vitro Study.

AIM: The aim of this study is to evaluate and compare the impact strength of conventional acrylic resin, high-impact acrylic resin, high-impact acrylic resin reinforced with silver nanoparticles, and high-impact acrylic resin reinforced with a zirconium oxide powder. MATERIALS AND METHODS: A total of 60 samples were prepared of dimensions 60 mm length × 7 mm width × 4 mm thickness to test impact strength. Machined stainless steel dies of the same dimension were used to form molds for the fabrication of these samples. Of 60 samples, 15 samples were prepared each from conventional acrylic resin (Group A1), high-impact acrylic resin (Group A2), acrylic resin reinforced with silver nanoparticles (Group A3), and acrylic resin reinforced with zirconium oxide powder (Group A4). Izod-Charpy pendulum impact testing machine was used. RESULTS: The impact strength of group A1 was in the range of 2.83-3.30 kJ/m2 (M = 3.12 kJ/m2, SD = 0.16), group A2 was in range of 5.10-5.78 kJ/m2 (M = 5.51 kJ/m2, SD = 0.18), group A3 was in range 3.18-3.56 kJ/m2 (M = 3.37 kJ/m2, SD = 0.11), and group A4 was in range 7.18-7.78 kJ/m2 (M = 7.5 kJ/m2, SD = 0.18). Statistical analysis using one-way ANOVA and t-test revealed significant differences (p < 0.001). CONCLUSION: High-impact acrylic resin reinforced with zirconium oxide powder has the highest impact strength. CLINICAL SIGNIFICANCE: This research sheds light on the usefulness of novel filler materials in clinical prosthodontics.

A Systematic Review of Cross-Sectional Studies Conducted in the Kingdom of Saudi Arabia on Levels of Dental Anxiety Between Genders and Demographic Groups.

BACKGROUND Dental anxiety can impact oral health and dental treatment in patients of all age groups, which seems to be an obstacle to quality dental care. This systematic review of the literature aimed to evaluate the findings from cross-sectional studies conducted in the Kingdom of Saudi Arabia (KSA) on levels of dental anxiety (DA) between genders and among various demographic groups. MATERIAL AND METHODS An electronic search of PubMed, Embase, and Web of Science databases was carried out in January 2022. Studies that measured dental anxiety in Saudis in all regions of the KSA by direct evaluation and interviews were included. Studies that were not in the English language or used proxy measures were excluded. Quality assessment was carried out using Joanna Briggs Institute's critical appraisal tool for cross-sectional studies. RESULTS A total of 19 cross-sectional studies from the KSA were identified that used validated anxiety scales, including the Corah Dental Anxiety Scale (DAS), the Corah Dental Anxiety Scale, Revised (DAS-R), and the Modified Dental Anxiety Scale (MDAS). All studies were rated as having a high risk of bias. A mild level of DA was the most common among participants in the KSA. CONCLUSIONS The findings from this systematic review showed that in the KSA, although a mild level of dental anxiety was most common in the study participants, women, young adults, and university students showed a higher prevalence of dental anxiety. However, the lack of sufficient literature to support the current findings make an overall conclusion about DA extremely difficult.

Evaluation of Mesiodistal Root Angulation of Permanent Incisors, Canines, and First Pre-Molars by Orthopantomogram Dental Imaging Findings in 296 Children Aged 6-14 Years.

BACKGROUND Early pre-eruptive inclination changes of the first premolar (FP) and its associative changes with canine (C) inclination are important to predict canine impaction. This study aimed to evaluate the mesiodistal root angulation of permanent lateral incisors (LI), canines, and first molars by orthopantomogram dental imaging in 296 children ages 6-14 years at a single center in India. MATERIAL AND METHODS The total number of participants was 296, with equal numbers of boys and girls divided into 4 age groups: 6-8 years, 8-10 years, 10-12 years, and 12-14 years. Angles between lateral incisor, erupting canine, and first pre-premolar with midline were measured on an orthopantomogram (dental imaging which includes all the teeth with TMJ). The angle between the erupting C with LI and erupting C with FP was measured. Pearson's correlation was also evaluated between the movement of the erupting canine with lateral incisor and erupting canine with erupting first premolar. RESULTS There was a significant difference in the angular values of different age groups (P≤0.05). The movements between LI, C, and FP were moderately correlated boys and girls aged 6-12 years. CONCLUSIONS The findings from this study showed that in boys and girls aged 6-14 years, eruption of the upper canine tooth was synchronized with eruption of the LI and FP.

Evaluation of Orthodontic Mini-Implant Placement in the Maxillary Anterior Alveolar Region in 15 Patients by Cone Beam Computed Tomography at a Single Center in South India.

BACKGROUND In this study, we aimed to evaluate orthodontic mini-implant placement in the maxillary anterior alveolar region by cone beam computed tomography (CBCT) in 15 patients at a single center in South India. MATERIAL AND METHODS A total of 15 CBCT scans of orthodontic patients after completion of leveling and aligning stage were included. The thickness of labial alveolar bone, labio-palatal bone, and inter-radicular distance between the maxillary central incisors (U1-U1), maxillary central and lateral incisor (U1-U2), and maxillary lateral incisor and canine (U2-U3) at vertical levels 4 mm, 6 mm, and 8 mm above the interdental cementoenamel junction were measured. Descriptive statistics, ANOVA, and Tukey post hoc tests were done to assess the differences among the groups. An independent t test was done to analyze differences by sex. RESULTS The thickness of cortical bone in the labial region was higher in the U2-U3 site than in the U1-U1 site, at a height of 4 mm. Also, there was a significant difference between 4 mm and 8 mm heights in the U2-U3 region. No significant difference was noted in bone dimensions among men and women and in the labio-palatal bone thickness among the different sites. The inter-radicular distance was the highest between the U2-U3 site, while it was the lowest in the U1-U2 site. CONCLUSIONS The findings from this center showed that when CBCT was used to evaluate orthodontic mini-implant placement in the maxillary anterior alveolar region, the U2-U3 and U1-U1 locations at heights between 6 mm to 8 mm apical to the interdental cementoenamel junction were optimal for placement of the mini-implants.

Suppression of Tumorigenicity 2 Pro-Inflammatory Biomarker Linking Diabetes Mellitus and Periodontitis: A Pilot Study.

BACKGROUND Suppression of tumorigenicity 2 (ST2) is a member of the interleukin (IL)-1 family and has 2 isoforms: ST2L, a transmembrane form, and ST2, a soluble form. IL-33 can act as an immune system alarm signal when released by damaged cells, which in turn activates other cells expressing the ST2 receptor. This can cause inflammatory cytokines to be released and produced, as well as trigger osteoclastogenesis. This study aimed to investigate the levels of soluble ST2 in gingival samples. MATERIAL AND METHODS The study population consisted of 30 individuals. The participants were divided into 3 groups: healthy participants, patients with periodontitis, and patients with periodontitis and diabetes mellitus. Periodontitis was determined using probing depth, clinical attachment loss, and gingival index. Patients with stage 2 to 4 periodontitis met the inclusion criteria. Gingival crevicular fluid (GCF) was collected for quantification of samples for ST2 levels by using an enzyme immunoassay. RESULTS The mean±standard deviation of ST2 GCF concentrations was relatively high (558.87±68.99) in the group with periodontitis and diabetes mellitus, compared with that of the periodontitis group (452.06±54.18) and healthy group (252.82±87.9). CONCLUSIONS GCF ST2 values were found to be a marker of inflammatory activities. Thus, GCF ST2 could be a potential biomarker for the diagnosis of periodontitis as well as systemic diseases, such as diabetes mellitus. This pilot study was limited by a small number of participants. To confirm the associations, more large-scale investigations should be conducted.

Gene Interaction Network Analysis Reveals IFI44L as a Drug Target in Rheumatoid Arthritis and Periodontitis.

OBJECTIVE: Despite extensive research on periodontitis and rheumatoid arthritis, the underlying molecular connectivity between these condition remains largely unknown. This research aimed to integrate periodontitis and rheumatoid arthritis gene expression profiles to identify interconnecting genes and focus to develop a common lead molecule against these inflammatory conditions. MATERIALS AND METHODS: Differentially expressed genes (DEGs) of periodontitis and rheumatoid arthritis were identified from the datasets retrieved from the Gene Expression Omnibus database. The network was constructed by merging DEGs, and the interconnecting genes were identified and ranked using GeneMANIA. For the selected top ranked gene, the potential inhibitor was searched using FINDSITEcomb2.0. Subsequently, the molecular docking and molecular dynamics were performed to determine the binding efficiency and protein-ligand complex stability, respectively. RESULTS: From the network analysis, IFN-induced protein 44-like (IFI44L) was identified as a top ranked gene involved in most of the immunological pathway. With further virtual screening of 6507 molecules, vemurafenib was identified to be the best fit against the IFI44L target. The binding energy and stability of IFI44L with vemurafenib were investigated using molecular docking and molecular dynamics simulation. Docking results show binding energy of -7.7 Kcal/mol, and the simulation results show stability till 100 ns. CONCLUSIONS: The identified IFI44L may represent a common drug target for periodontitis and rheumatoid arthritis. Vemurafenib could be a potent anti-inflammatory drug for both diseases.

Plant-Derived Antiviral Compounds as Potential Entry Inhibitors against Spike Protein of SARS-CoV-2 Wild-Type and Delta Variant: An Integrative in SilicoApproach.

The wild-type SARS-CoV-2 has continuously evolved into several variants with increased transmissibility and virulence. The Delta variant which was initially identified in India created a devastating impact throughout the country during the second wave. While the efficacy of the existing vaccines against the latest SARS-CoV-2 variants remains unclear, extensive research is being carried out to develop potential antiviral drugs through approaches like in silico screening and drug-repurposing. This study aimed to conduct the docking-based virtual screening of 50 potential phytochemical compounds against a Spike glycoprotein of the wild-type and the Delta SARS-CoV-2 variant. Subsequently, molecular docking was performed for the five best compounds, such as Lupeol, Betulin, Hypericin, Corilagin, and Geraniin, along with synthetic controls. From the results obtained, it was evident that Lupeol exhibited a remarkable binding affinity towards the wild-type Spike protein (-8.54 kcal/mol), while Betulin showed significant binding interactions with the mutated Spike protein (-8.83 kcal/mol), respectively. The binding energy values of the selected plant compounds were slightly higher than that of the controls. Key hydrogen bonding and hydrophobic interactions of the resulting complexes were visualized, which explained their greater binding affinity against the target proteins-the Delta S protein of SARS-CoV-2, in particular. The lower RMSD, the RMSF values of the complexes and the ligands, Rg, H-bonds, and the binding free energies of the complexes together revealed the stability of the complexes and significant binding affinities of the ligands towards the target proteins. Our study suggests that Lupeol and Betulin could be considered as potential ligands for SARS-CoV-2 spike antagonists. Further experimental validations might provide new insights for the possible antiviral therapeutic interventions of the identified lead compounds and their analogs against COVID-19 infection.

Modern Applications and Innovations of 3D Dental Imaging.

Recent improvements in imaging techniques have profoundly facilitated the diagnosis of pathologies of the maxillofacial district and provided all the information necessary to plan an adequate treatment plan. Three-dimensional (3D) radiographic diagnostic exams, reworked by specific software that allow easy viewing of images and various graphic reworkings, are frequently applied to maxillofacial district for the diagnosis of various pathologies, which, until a few years ago, required several radiographic examinations.1,2.

Root Membrane Concept: Shield the Socket-A Case Report.

Edentulousness affects the mental health of most patients. Missing teeth in the anterior esthetic zones is a matter of concern, especially for young adults. Various replacement options such as fixed partial dentures, removable partial dentures, and dental implants are available to treat edentulousness. Dental implants have been a booming treatment option in modern-day dentistry as they more closely mimic the natural tooth. The most important criterion for placement of the implant in the esthetic zone is the conservation of alveolar bone, especially in the anterior region which is usually compromised due to tooth extraction or resorption of the ridge. The root membrane concept or the socket shield technique is a recently introduced concept in implant dentistry where a portion of the root acts as a shield to protect against alveolar bone resorption and maintain bone integrity, especially in the esthetic area. This case report describes the clinical management of fractured upper anterior teeth using a dental implant and the root membrane technique. Keywords: Anterior zone, Esthetics, Immediate implants, Implant, Missing teeth, Root membrane technique, Socket shield.

Techniques for Extraction Socket Regeneration for Alveolar Ridge Preservation.

BACKGROUND: Alveolar bone undergoes volumetric changes after extraction due to physiologic bone remodeling. The amount of alveolar bone available during prosthodontic treatment can affect the esthetic outcome of the treatment and make implant placement challenging. Socket preservation techniques are advocated postextraction to maintain the bone's vertical and horizontal alveolar bone dimensions and prevent its atrophy. AIM: This review is oriented toward a clinician, describing the different materials and techniques in practice today for socket preservation. REVIEW RESULTS: A variety of methods have been studied as a means to stop alveolar ridge resorption. While immediate implant placement was recommended as a socket preservation technique, clinical trials have not demonstrated favorable results. The main techniques favored by clinicians today involve bone grafts, bone substitutes, barrier membranes, and combinations thereof. As with periodontal defects, these materials show favorable outcomes in alveolar bone regeneration and ridge preservation. Tooth bone grafts, both autogenous and allogenous, have been recommended recently for ridge preservation as they are chemically similar to bone and can induce osteogenesis. The use of autologous platelet concentrates has yielded contradictory results in studies. Cutting-edge approaches entail using growth factors and tissue engineering concepts. While these strategies are still in the development stages, it has peerless potential in preserving and regenerating alveolar bone. CONCLUSION: Alveolar ridge resorption is an unavoidable physiological process after extraction and leads to severe bone deficiencies, affecting esthetics. These changes in alveolar ridge dimensions make implant placement difficult and affect the longevity of the implant. Clinical intervention can prevent alveolar bone resorption and preserve the ridge. Bone grafts and substitutes including concentrates remain the best choices in ride preservation. The use of growth factors and tissue engineering concepts requires further clinical trials before widespread use in clinical practice.

Effectiveness of Online Learning vs Traditional Learning during COVID-19 Pandemic in Chennai: A Questionnaire Study.

BACKGROUND: Digitalization of education became a need of the hour when the COVID-19 pandemic affected the traditional modalities of learning, and it was widely implemented in various fields including dentistry. AIMS: The aim of this study was to assess the effectiveness of online learning against traditional learning systems among dental students in Chennai. METHODS AND MATERIALS: A Google Form questionnaire comprising 29 dental learning-based questions was designed and distributed to dental students across colleges in Chennai using online distribution platforms. The study responses were closed after the stipulated period of 1 month. The data were analyzed using SPSS software version 17. RESULTS: The survey was answered by 834 participants comprising 76.9% females and 22.3% males. Of the total study population, 71.1% of them did not have previous online learning experiences. Approximately, 15.5% of the study population were not satisfied with the facilities provided by the online learning platforms. Also, one-third of the study population reported difficulty during the presentation. Three-fourths of the study participants did not prefer online learning over traditional learning and reported that the attention span and communication between the students and teachers were lower in online classes. Overall, 43% of the study participants rated the quality of online video-based learning to be good and 8.5% found it to be poor. CONCLUSION: Online-based learning systems are evolving and can provide a wide array of knowledge from global experts. However, structured planning and technique may be needed for the dental curriculum.

Influence of Human and Bacterial Enzymes on Resin Restorations: A Review.

BACKGROUND: Esthetic satisfaction has been a prime concern for patients. This has led to a surge in the development of esthetic restorations and dental composites in the field of restorative dentistry over the past decade. Resins are the most preferred restorative material. However, their failure rate was observed to be high. AIM: This review is aimed for clinician, discussing the influence of human and bacterial enzymes on resin restorations. REVIEW RESULTS: Composite restoration failure is multifactorial with an interplay of mechanical functions such as masticatory forces and abrasion with biological factors such as host modulated and bacterial enzymes. Salivary esterases and bacterial esterases act on the ester-link bond of resin restoration to form byproducts of methacrylic acid and Bis-hydroxy-propoxy-phenyl-propane. Salivary enzymes form microgaps between the resin-tooth interface and provide a suitable environment for bacterial growth. Bacteria colonize the resin-tooth interface to weaken the resin bond strength. The presence of bacteria draws neutrophils into the hybrid layer. The activation and degranulation of neutrophils leads to enzyme secretions that act on bacteria. However, this can also have adverse effects on resin restoration. Acids prompt the activation of matrix metalloproteinases (MMPs). Proteinases secreted by MMPs uncoil the collagen fibrils of the dentin matrix and degrade tooth structure. The salivary esterases, bacterial esterases, neutrophils, and MMPs work synergistically to degrade dental resin material, resin-tooth interface, and dentin. This causes failure of dental resin restorations and secondary caries formation. CONCLUSION: Biological degradation of resin restorations is inevitable irrespective of the material and techniques used. Salivary esterases such as cholesterol esterase and pseudocholinesterase and cariogenic bacterial esterase can degrade dental resin, weakening the hybrid layer at the resin-tooth interface, affecting the bond strength, and causing failure. Ester-free resin and incorporation of antimicrobial materials, esterase, and MMP inhibitors are strategies that could ameliorate degradation of the restoration.

Reliability of Frankfort Horizontal Plane with True Horizontal Plane in Cephalometric Measurements.

INTRODUCTION: The purpose of the study is to determine reliability of true horizontal (TH) plane with Frankfort horizontal (FH) plane in cephalometric measurements. MATERIALS AND METHODS: One hundred lateral cephalograms were collected and traced using FACAD software, all cephalometric measurements which included FH plane as reference planes were used in this study. Cephalometric tracing was done with FH plane as reference plane and another set of measurements with TH plane as reference plane was done. Statistical tests were done using independent sample t-test (p <0.05). RESULTS: Results of an independent t-test revealed a statistically insignificant difference that was observed for all the parameters assessed (p <0.05). Both angular and linear measurements showed an insignificant difference between FH and TH. CONCLUSION: Within the limitations of the study, the results show that the FH plane is closest and as reliable as the TH plane. The variation of FH was least for all the parameters assessed.

Role of Periodontal Bacteria, Viruses, and Placental mir155 in Chronic Periodontitis and Preeclampsia-A Genetic Microbiological Study.

Previous studies assessed the involvement and impact of periodontal bacteria in preeclamptic women with chronic periodontitis. To explore further, the current study aimed to associate periodontal viruses and bacteria with mir155 levels in placental tissues of preeclamptic women with generalized chronic periodontitis. Four-hundred 45 pregnant women, 18-35 years of age, were selected and divided into four groups (controls, A, B, and C) where the Controls included 145 systemically and periodontally healthy pregnant women Group A-100 systemically healthy pregnant women with chronic periodontitis, Group B- 100 preeclamptic women with chronic periodontitis, Group C- 100 preeclamptic women without chronic periodontitis. Age, BMI, SES, and periodontal parameters such as PI, BOP, PPD, and CAL were noted. Periodontal pathogens such as Tf, Td, Pg, Pi, Fn, HSV, EBV, and HCMV were tested in subgingival plaque, placental tissues, and mir155. We observed that PI, BOP, PPD, CAL, Tf, and EBV were highly significant in Group B. We found a higher number of periodontal bacteria, viruses, and mir 155 in Group B showing a higher risk of preeclampsia. More genetic studies in this field are advised to ascertain the role of periodontopathogens and mir 155 in preeclampsia and periodontal inflammation. What is already known on this subject? Periodontal diseases pose an increased risk of developing preeclampsia and delivering preterm and/or low-birth-weight babies. What do the results of this study add? Periodontal variables such as PI, pocket depth, BOP, and clinical attachment levels, were found to be increased in the preeclamptic women with chronic periodontitis. The significant difference was seen in the relative fold expression of mir155 with higher gene expression of mir155 in groups B and A as compared to group C and controls. What are the implications of these findings for clinical practice and/or further research? In our study, mir155 correlation with the periodontal parameters and periodontal pathogens further strengthen the evidence of periodontal inflammation as a risk of preeclampsia in pregnant women especially when associated with chronic periodontitis. mir155 can be considered to be one of the genetic biomarkers and can be used as a diagnostic tool for the early detection of PE.

Allicin May Promote Reversal of T-Cell Dysfunction in Periodontitis via the PD-1 Pathway.

We evaluated the role of allicin in periodontitis using an in silico and in vitro design. An in silico docking analysis was performed to assess the plausible interactions between allicin and PD-L1. The cytokine profile of gingival crevicular fluid (GCF) samples obtained from periodontitis patients was estimated by cytometric bead array. CD3+ lymphocytes isolated from the peripheral blood were sorted and characterized using immunomagnetic techniques. Cultured and expanded lymphocytes were treated with the GCF samples to induce T-cell exhaustion. Optimum concentrations of allicin were added to exhausted lymphocytes to compare the expression of TIM-3 and LAG-3 gene expression at baseline and post-treatment. Allicin was found to bind to the PD-L1 molecule as revealed by the in-silico experiment, which is possibly an inhibitory interaction although not proven. GCF from periodontitis patients had significantly higher concentrations of TNF-α, CCL2, IL-6, IFN-γ, and CXCL8 than controls. GCF treatment of CD3+ lymphocytes from the periodontitis patients significantly increased expression of T-cell exhaustion markers TIM-3 and LAG-3. Allicin administration with GCF treatment resulted in significant lowering of the expression of exhaustion markers. Allicin may exert an immunostimulatory role and reverse immune-destructive mechanisms such as T-cell exhaustion.

The Growth Factors and Cytokines of Dental Pulp Mesenchymal Stem Cell Secretome May Potentially Aid in Oral Cancer Proliferation.

BACKGROUND: Growth factors and cytokines responsible for the regenerative potential of the dental pulp mesenchymal stem cell secretome (DPMSC-S) are implicated in oral carcinogenesis. The impact and effects of these secretory factors on cancer cells must be understood in order to ensure their safe application in cancer patients. OBJECTIVE: We aimed to quantify the growth factors and cytokines in DPMSC-S and assess their effect on oral cancer cell proliferation. MATERIALS AND METHODS: DPMSCs were isolated from patients with healthy teeth (n = 5) that were indicated for extraction for orthodontic reasons. The cells were characterized using flow cytometry and conditioned medium (DPMSC-CM) was prepared. DPMSC-CM was subjected to a bead-based array to quantify the growth factors and cytokines that may affect oral carcinogenesis. The effect of DPMSC-CM (20%, 50%, 100%) on the proliferation of oral cancer cells (AW123516) was evaluated using a Ki-67-based assay at 48 h. AW13516 cultured in the standard growth medium acted as the control. RESULTS: VEGF, HCF, Ang-2, TGF-α, EPO, SCF, FGF, and PDGF-BB were the growth factors with the highest levels in the DPMSC-CM. The highest measured pro-inflammatory cytokine was TNF-α, followed by CXCL8. The most prevalent anti-inflammatory cytokine in the DPMSC-CM was IL-10, followed by TGF-ß1 and IL-4. Concentrations of 50% and 100% DPMSC-CM inhibited Ki-67 expression in AW13516, although the effect was non-significant. Moreover, 20% DPMSC-CM significantly increased Ki-67 expression compared to the control. CONCLUSIONS: The increased Ki-67 expression of oral cancer cells in response to 20% DPMSC-CM indicates the potential for cancer progression. Further research is needed to identify their effects on other carcinogenic properties, including apoptosis, stemness, migration, invasion, adhesion, and therapeutic resistance.

An Update of Possible Radiation-free Imaging Techniques in Dentistry.

Cone-beam computed tomography (CBCT) represents today the most widespread and most used 3D examination in dentistry. It is precise because of its usefulness in orthodontics and orthognathic surgery with large field of view (FOVs); in oral surgery and implantology for the 3D evaluation of bone volumes and proximity to noble structures; and in endodontics for the understanding of the often difficult root canal system anatomy with reduced FOV and greater resolution that this imaging technique, also considering the wide diffusion and availability in dental offices, in addition to the short examination execution times, allows its wide use.1-4.

Mechanical Characteristics, Testing, and Future Perspective of Nickel-Titanium Rotary Instruments.

The main drawback of several studies is the limited analysis performed for the comparison of nickel-titanium (NiTi) rotary systems. Most often, research articles in this area are focalized on the static characteristics such as static cyclic fatigue, torsional loads, and flexibility, not considering their reciprocal interaction and all dynamic factors.1 Recent evidence in the literature defines the reciprocal interaction between these parameters as a fundamental element in the study of their mechanical characteristics.2 However, static mechanical behavior is fundamental to assess the basic performance of NiTi instruments, but its interpretation during clinical practice is pointless as it does not resemble the real clinical scenario.1,3,4 Results arising from static tests, certainly valid as a first approach to the evaluation of an instrument recently introduced on the market, and comparative evaluations, should be considered in a general and more complete view, considering their reciprocal relationships.3-6 For these reasons, different types of researches that investigate both static and dynamic performance of NiTi instruments should be strongly recommended in order to give to original research and in vitro study an actual clinical significance, certainly much more indicative in view of a subsequent clinical application of NiTi rotary instruments.7-9.