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Frontiers in Bioscience (Landmark... Jun 2024Dental pulp stem cells (DPSCs) have self-renewal and multidirectional differentiation potentials. As such, DPSCs have a wide range of clinical applications. Low-level...
BACKGROUND
Dental pulp stem cells (DPSCs) have self-renewal and multidirectional differentiation potentials. As such, DPSCs have a wide range of clinical applications. Low-level laser therapy (LLLT) has positive photobiostimulatory effects on cell proliferation, angiogenesis, osteogenic differentiation, bone regeneration, and fracture healing. However, there have been few studies on the effect of low-energy lasers on DPSC proliferation.
METHODS
DPSCs were obtained from dental pulp tissue. The effects of LLLT on the proliferation of DPSCs and the associated mechanisms were investigated by culture and laser irradiation.
RESULTS
LLLT with energy densities of 3.5 J/cm2 and 14 J/cm2promoted the proliferation of DPSCs. Differential protein expression studies suggested the stimulation of DPSC proliferation by LLLT involved the PI3K-Akt and Rap1 signaling pathways, as well as the apoptosis-related pathway.
CONCLUSION
This preliminary study demonstrated that low-energy lasers have a pro-proliferative effect on DPSCs, and identified possible associated mechanisms. Our findings provide a theoretical basis for the clinical application of DPSCs and suggest novel strategies for the treatment of related diseases.
Topics: Dental Pulp; Cell Proliferation; Humans; Stem Cells; Low-Level Light Therapy; Cells, Cultured; Signal Transduction; Apoptosis; Cell Differentiation
PubMed: 38940041
DOI: 10.31083/j.fbl2906211 -
Frontiers in Cellular and Infection... 2024Recent studies have demonstrated a positive role of hyaluronic acid (HA) on periodontal clinical outcomes. This study aimed to investigate the impact of four different...
INTRODUCTION
Recent studies have demonstrated a positive role of hyaluronic acid (HA) on periodontal clinical outcomes. This study aimed to investigate the impact of four different HAs on interactions between periodontal biofilm and immune cells.
METHODS
The four HAs included: high-molecular-weight HA (HHA, non-cross-linked), low-molecular-weight HA (LHA), oligomers HA (OHA), and cross-linked high-molecular-weight HA (CHA). Serial experiments were conducted to verify the influence of HAs on: (i) 12-species periodontal biofilm (formation and pre-existing); (ii) expression of inflammatory cytokines and HA receptors in monocytic (MONO-MAC-6) cells and periodontal ligament fibroblasts (PDLF) with or without exposure to periodontal biofilms; (iii) generation of reactive oxygen species (ROS) in MONO-MAC-6 cells and PDLF with presence of biofilm and HA.
RESULTS
The results indicated that HHA and CHA reduced the bacterial counts in a newly formed (4-h) biofilm and in a pre-existing five-day-old biofilm. Without biofilm challenge, OHA triggered inflammatory reaction by increasing IL-1β and IL-10 levels in MONO-MAC cells and IL-8 in PDLF in a time-dependent manner, whereas CHA suppressed this response by inhibiting the expression of IL-10 in MONO-MAC cells and IL-8 in PDLF. Under biofilm challenge, HA decreased the expression of IL-1β (most decreasing HHA) and increased IL-10 levels in MONO-MAC-6 cells in a molecular weight dependent manner (most increasing CHA). The interaction between HA and both cells may occur via ICAM-1 receptor. Biofilm stimulus increased ROS levels in MONO-MAC-6 cells and PDLF, but only HHA slightly suppressed the high generation of ROS induced by biofilm stimulation in both cells.
CONCLUSION
Overall, these results indicate that OHA induces inflammation, while HHA and CHA exhibit anti-biofilm, primarily anti-inflammatory, and antioxidant properties in the periodontal environment.
Topics: Biofilms; Hyaluronic Acid; Humans; Reactive Oxygen Species; Fibroblasts; Cytokines; Monocytes; Periodontal Ligament; Cell Line; Interleukin-1beta; Interleukin-10
PubMed: 38938883
DOI: 10.3389/fcimb.2024.1414861 -
BMC Oral Health Jun 2024To examine the patterns of pretreatment facial soft tissue shape in orthodontic cases with premolar extraction using artificial intelligence (AI) and to investigate the... (Comparative Study)
Comparative Study
OBJECTIVE
To examine the patterns of pretreatment facial soft tissue shape in orthodontic cases with premolar extraction using artificial intelligence (AI) and to investigate the corresponding changes.
METHODS
One hundred and fifty-two patients who underwent orthodontic treatment with premolar extraction were enrolled. Lateral cephalograms were obtained before and after the treatment. For each record, the outlines of the nose-lip-chin profile and corresponding 21 cephalometric variables were extracted. The AI method classified pretreatment records into three subject groups based on the feature variables extracted from the outline. Dentoskeletal and soft tissue facial form changes observed after treatment were compared statistically (P < 0.05) between the groups using ANOVA. Multivariate regression models were used for each group.
RESULTS
Group 1 (n = 59) was characterized by Class II high-angle retrognathic mandible with an incompetent lip, group 2 (n = 55) by Class I malocclusion with retruded and thin lips, and group 3 (n = 38) by Class I malocclusion with an everted superior lip before treatment. The ratios of anteroposterior soft tissue to hard tissue movements in Group 1 were 56% (r = 0.64) and 83% (r = 0.75) for the superior and inferior lips, respectively, whereas those in Group 2 were 49% (r = 0.78) and 91% (r = 0.80), and 40% (r = 0.54) and 79% (r = 0.70), respectively, in Group 3.
CONCLUSIONS
The modes of facial form changes differed depending on the pre-treatment profile patterns classified by the AI. This indicates that the determination of the pre-treatment profile pattern can help in the selection of soft tissue to hard tissue movement ratios, which helps estimate the post-treatment facial profile with a moderate to high correlation.
Topics: Humans; Cephalometry; Face; Bicuspid; Tooth Extraction; Female; Male; Lip; Adolescent; Nose; Malocclusion, Angle Class I; Artificial Intelligence; Chin; Malocclusion, Angle Class II; Mandible; Tooth Movement Techniques; Child; Young Adult; Malocclusion
PubMed: 38937790
DOI: 10.1186/s12903-024-04512-2 -
BMC Oral Health Jun 2024The desirable properties of silver diamine fluoride (SDF) make it an effective agent for managing dental caries and tooth hypersensitivity. There are several clinical...
BACKGROUND
The desirable properties of silver diamine fluoride (SDF) make it an effective agent for managing dental caries and tooth hypersensitivity. There are several clinical instances that SDF application might precede the placement of direct tooth-colored restorations. On the other hand, SDF stains demineralized/carious dental tissues black, which might affect the esthetic outcomes of such restorations. Color is a key parameter of esthetics in dentistry. Therefore, this study aims to systematically review dental literature on color/color change of tooth-colored restorations placed following the application of SDF on dentine.
METHODS
Comprehensive search of PubMed, Embase, Scopus and ISI Web of Science databases (until August 2023) as well as reference lists of retrieved studies was performed. In vitro studies reported color or color change of tooth-colored restorative materials applied on SDF-treated dentine were included. Methodological quality assessment was performed using RoBDEMAT tool. Pooled weighted mean difference (WMD) and 95% confidence interval (95% CI) was calculated.
RESULTS
Eleven studies/reports with a total of 394 tooth-colored restorations placed following a) no SDF (control) or b) SDF with/without potassium iodide (KI)/glutathione dentine pre-treatments were included. Color change was quantified using ∆E formulas in most reports. The pooled findings for the comparison of resin-based composite (RBC) restorations with and without prior 38% SDF + KI application revealed no statistically significant differences in ∆E values at short- and long-term evaluations (~ 14 days: WMD: -0.56, 95% CI: -2.09 to 0.96; I: 89.6%, and ~ 60 days: WMD: 0.11; 95% CI: -1.51 to 1.72; I: 76.9%). No studies provided sufficient information for all the items in the risk of bias tool (moderate to low quality).
CONCLUSIONS
The limited evidence suggested comparable color changes of RBC restorations with and without 38% SDF + KI pre-treatment up to 60 days. The included studies lacked uniformity in methodology and reported outcomes. Further studies are imperative to draw more definite conclusions.
PROTOCOL REGISTRATION
The protocol of this systematic review was registered in PROSPERO database under number CRD42023485083.
Topics: Silver Compounds; Humans; Quaternary Ammonium Compounds; Fluorides, Topical; Dentin; Color; Dental Restoration, Permanent
PubMed: 38937760
DOI: 10.1186/s12903-024-04487-0 -
American Journal of Orthodontics and... Jul 2024
Topics: Humans; Molar, Third; Tooth Extraction; Molar; Tooth Eruption; Maxilla; Tooth, Impacted
PubMed: 38936982
DOI: 10.1016/j.ajodo.2024.03.004 -
In Vivo (Athens, Greece) 2024Recent reports indicate that sclerostin is secreted by periodontal ligament tissue-derived (PDL) cells during orthodontic force loading and that the secreted sclerostin...
BACKGROUND/AIM
Recent reports indicate that sclerostin is secreted by periodontal ligament tissue-derived (PDL) cells during orthodontic force loading and that the secreted sclerostin contributes to bone metabolism. However, the detailed mechanism is poorly understood. The aim of this study was to determine how PDL cells affect bone formation.
MATERIALS AND METHODS
Rat periodontal ligament tissue was immunohistochemically stained for sclerostin. Cultured primary PDL cells, osteoblasts, and skin fibroblasts (Sfbs) isolated from rat periodontal ligament tissue, calvaria, and skin, respectively, were examined. Osteoblasts were cultured with control conditioned medium (Cont-CDM) and PDL cell culture conditioned medium (PDL-CDM) for up to 21 days. Cultured osteoblasts were then stained with alkaline phosphatase and von Kossa stain. Osteoblasts cultured in each conditioned medium were analyzed by real-time quantitative PCR for bone Gla protein (Bgp), Axin2, and Ki67 expression. PDL cells used to obtain conditioned medium were analyzed for Sost, Ectodin and Wnt1 expression and compared with expression in Sfbs.
RESULTS
Expression of sclerostin was observed in periodontal ligament tissue by immunohistochemical staining. The formation of mineralization nodules was inhibited in PDL-CDM compared with Cont-CDM in osteoblast culture. In PDL-CDM, the expression levels of Bgp and Axin2 in osteoblasts were decreased compared with Cont-CDM. In PDL cells, expression levels of Sost and Ectodin were much higher than in Sfbs; however, expression of Wnt1 was lower in PDL cells compared with Sfbs.
CONCLUSION
PDL cells secrete various proteins, including sclerostin and suppress osteogenesis in osteoblasts through the canonical Wnt pathway.
Topics: Periodontal Ligament; Animals; Osteogenesis; Osteoblasts; Rats; Culture Media, Conditioned; Cells, Cultured; Male; Fibroblasts; Cell Differentiation; Immunohistochemistry; Bone Morphogenetic Proteins; Genetic Markers
PubMed: 38936890
DOI: 10.21873/invivo.13609 -
PloS One 2024The patterning cascade model of crown morphogenesis has been studied extensively in a variety of organisms to elucidate the evolutionary history surrounding postcanine...
OBJECTIVE
The patterning cascade model of crown morphogenesis has been studied extensively in a variety of organisms to elucidate the evolutionary history surrounding postcanine tooth form. The current research is the first to use a large modern human sample to examine whether the crown configuration of lower deciduous and permanent molars aligns with expectations derived from the model. This study has two main goals: 1) to determine if metameric and antimeric pairs significantly differ in size, accessory trait expression, and relative intercusp spacing, and 2) assess whether the relative distance among early-forming cusps accounts for observed variation in accessory cusp expression.
METHODS
Tooth size, intercusp distance, and morphological trait expression data were collected from 3D scans of mandibular dental casts representing participants of the Harvard Solomon Islands Project. Paired tests were utilized to compare tooth size, accessory trait expression, and relative intercusp distance between diphyodont metameres and permanent antimeres. Proportional odds logistic regression was implemented to investigate how the odds of greater accessory cusp expression vary as a function of the distance between early-developing cusps.
RESULTS/SIGNIFICANCE
Comparing paired molars, significant differences were identified for tooth size and cusp 5 expression. Several relative intercusp distances emerged as important predictors of cusp 6 expression, however, results for cusp 5 and cusp 7 did not match expected patterns. These findings support previous quantitative genetic results and suggest the development of neighboring crown structures represents a zero-sum partitioning of cellular territory and resources. As such, this study contributes to a better understanding of the foundations of deciduous and permanent molar crown variation in humans.
Topics: Humans; Tooth Crown; Molar; Dentition, Permanent; Morphogenesis; Tooth, Deciduous; Odontogenesis; Male; Child; Female
PubMed: 38935640
DOI: 10.1371/journal.pone.0304455 -
International Journal of Implant... Jun 2024This propensity score matching, multicenter, cross-sectional study was performed to examine the effects of various prosthetic methods for dental clinic outpatients with...
Effects of various prosthetic methods for patients with Kennedy Class I partial edentulism on oral hypofunction, subjective symptoms, and oral health-related quality of life.
PURPOSE
This propensity score matching, multicenter, cross-sectional study was performed to examine the effects of various prosthetic methods for dental clinic outpatients with Kennedy Class I partial edentulism (KCIPE) on oral hypofunction, subjective frailty symptoms, and oral health-related quality of life (QOL).
METHODS
Patients (n = 348) were classified into the following three groups for analysis: NT, patients with natural dentition providing intermaxillary contact in four occlusal supporting zones; RPD, patients with KCIPE who received removable partial dentures; and ISFP, patients with KCIPE who received implant-supported fixed prostheses. Participants' basic characteristics were recorded, and oral function tests were conducted. Subjective symptoms of physical and oral frailty were investigated via questionnaire. Oral health-related QOL was assessed using the Japanese short version of the Oral Health Impact Profile (OHIP-JP16). Propensity score matching was performed to adjust for patient background factors that could influence oral hypofunction in each group.
RESULTS
Compared with the ISFP group, the RPD group had significantly higher rates of poor oral hygiene, reduced occlusal force, decreased masticatory function, and declines in swallowing function and oral hypofunction; the odds ratio for oral hypofunction was 4.67. Compared with the ISFP group, the RPD group had significantly greater subjective symptoms of physical frailty and oral frailty, as well as higher OHIP scores.
CONCLUSIONS
Prosthetic treatment of KCIPE affected oral hypofunction, subjective frailty symptoms, and oral health-related QOL in dental clinic outpatients.
Topics: Humans; Quality of Life; Cross-Sectional Studies; Male; Female; Middle Aged; Oral Health; Jaw, Edentulous, Partially; Denture, Partial, Removable; Aged; Surveys and Questionnaires; Propensity Score; Dental Prosthesis, Implant-Supported; Denture, Partial, Fixed; Adult
PubMed: 38935335
DOI: 10.1186/s40729-024-00555-w -
American Journal of Orthodontics and... Jun 2024This study evaluated the probability of developing malocclusions in mixed dentition.
INTRODUCTION
This study evaluated the probability of developing malocclusions in mixed dentition.
METHODS
A longitudinal study was conducted with 598 children (aged 5 years) in deciduous dentition. The children were followed for 3 years until mixed dentition (aged 8 years). Overjet, overbite, and transversal relations were evaluated. Bayesian models were used to analyze the data and estimate the parameters.
RESULTS
The parameter θ was used for the distributions, indicating the probability of presenting a given condition with a credibility index (ICr) of 95%. After 3 years of follow-up, 121 children were reevaluated. The results showed that children have a high probability of malocclusion in mixed dentition. There was a higher probability of developing an increased overjet in the mixed dentition of 20.5% (ICr 95%, 13.6-28.4) to 48.3% (ICr 95%, 39.1-57.7) and a higher probability of having a normal overbite in the deciduous dentition and a lower probability in the mixed dentition (ICr 95%, 9.2-21.3).
CONCLUSIONS
Considering the probabilistic model of Bayesian analysis, children with normal overjet in the deciduous dentition may show an increased overjet in the mixed dentition. Concerning overbite, children may present an anterior open bite during the transition between deciduous and mixed dentition, as well as self-correction of deep overbite in mixed dentition. Furthermore, they may present a posterior crossbite during the mixed dentition when there is a normal transverse relationship in the deciduous dentition.
PubMed: 38935005
DOI: 10.1016/j.ajodo.2024.05.011 -
Indian Journal of Dental Research :... Jan 2024During orthodontic treatment, temporary anchoring devices (TADs) are used to restrain tooth movement. They are a relatively recent addition to the dental toolkit.
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.
Topics: Humans; Orthodontic Anchorage Procedures; Cone-Beam Computed Tomography; Zygoma; Bone Screws; Male; Female; Bicuspid; Maxilla; Tooth Movement Techniques
PubMed: 38934757
DOI: 10.4103/ijdr.ijdr_143_23