BMC Oral Health最新文献

Background: There are differences in the research results regarding which edge design of occlusal veneers can achieve the best long-term success rate as a relatively new fixed prosthesis restoration method. Further research is needed. The three-dimensional finite element method was used to conduct stress analysis on occlusal veneers of maxillary first permanent molars with different thicknesses and margin preparation designs. The aim of this study was to provide mechanical research evidence and a reference for exploring standardized clinical protocols for the design of occlusal veneer restorations of maxillary first molars.

Method: A 3Shape (Intraoral Scanner) was used to scan the maxillary first molar teeth in vitro, after which 3D printing was carried out. Three different edge designs were applied to identical teeth: straight-beveled finishing line(SFL), chamfer finishing line(CFL), and standard cuspal inclination(SCI). Preparation was carried out with a thickness of 0.5 mm. Using the surface deformation feature, the occlusal veneer was thickened to 0.5 mm and 1.0 mm, and periodontal ligaments were added. They were then placed into the upper and lower jaws and dental arches. Finite element analysis was performed after applying bite force dispersion to the loading area on the mandible following dynamic contact.

Results: (1) As the thickness increased, the maximum Von Mises stress in the occlusal veneers SFL and CFL also increased, while the SCI exhibited the opposite trend. (2). The trend of the maximum Von Mises stress in the adhesive layer decrease gradually with increasing thickness of the occlusal veneer. The stresses of the SFL and CFL is concentrated primarily at the edge position below the functional cusp, resulting in relatively low adhesive stress. However, in the SCI group, the maximum stress at the edge of the adhesive layer exceeds the maximum shear strength of commonly used adhesives.

Conclusions: Under the experimental conditions, the mechanical properties of the maximum Von Mises stress in the SFL, CFL, and SCI occlusal veneers meet clinical needs. Incorporating the minimally invasive concept of tooth preservation, a thickness of 1.0 mm are optimal for glass ceramic occlusal veneers on maxillary first molars.

Aim: The current umbrella review aimed to summarize the effect of erbium-doped yttrium aluminum garnet (Er: YAG) laser adjunct with the conventional non-surgical periodontal treatment which was evidenced from available systematic reviews.

Methods: An extensive literature search was piloted by two independent reviewers in the PubMed, Scopus, Science Direct, and Google Scholar databases. The search was limited to the English language from 2011 to 2023 years. The methodological quality of systematic reviews 2 (AMSTAR 2) guideline was followed to evaluate the risk of bias for the selected studies. Cohen's kappa statistic was implemented to evaluate the level of agreement to assess the risk of bias in the selected studies.

Results: A total of 472 studies were initially identified. After removing the duplicates and screening, a total of four studies were selected for the current overview. Based on the quality assessment tool, each study scored as high, moderate, low, and critically low-quality study following AMSTAR 2 tool. Inter-rater reliability by Cohen's Kappa statistics showed near-perfect agreement (0.95) between the two reviewers.

Conclusion: Even though weak evidence of effectiveness was observed for Er: YAG laser application in non-surgical periodontal treatment, the clinical benefits are still lacking.

The aim of this systematic review was to assess the antimicrobial effectiveness of silver nanoparticles (AgNPs) incorporated to different orthodontic bonding systems. Additionally, the review investigated the impact of AgNPs on the bonding properties of these materials. The hypothesis posed that the addition of AgNPs would enhance the antimicrobial efficacy of orthodontic bonding systems while maintaining their bonding properties. The systematic review employed a PICO-based search strategy, targeting in vitro studies focusing on the integration of nano silver particles into orthodontic bonding systems with potential antimicrobial activity. The intervention involved the use of nano silver in orthodontic bonding systems, with a comparison to systems lacking nano silver. The primary outcomes assessed were antimicrobial activity and shear bond strength (SBS). The search process, conducted without publication date restrictions, yielded 551 potential articles: 34 from PubMed, 360 from PubMed Central, 42 from Embase, 54 from Scopus, and 61 from Web of Science. Ultimately, a qualitative synthesis was conducted on 13 papers. The PRISMA diagram, visually represented the search strategy, screening process, and inclusion criteria. The study protocol was registered in PROSPERO CRD42023487656 to enhance transparency and adherence to systematic review guidelines. Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale, revealing that the 13 articles meeting the inclusion criteria demonstrated a high level of evidence. Seven studies were included in the meta-analysis regarding shear bond strength. In summary, the synthesized findings from these studies strongly underscore the promising potential of orthodontic materials modified with AgNPs. These materials exhibit effective resistance against cariogenic bacteria without compromising bonding properties below clinical acceptability. Such innovative materials hold significant implications for advancing oral health within the realm of orthodontics.

Background: Fixed orthodontic appliances act as a niche for microbial growth and colonization. Coating orthodontic wires with antimicrobial silver nanoparticles (AgNPs) and nanocomposite was adopted in this study to augment the biological activity of these wires by increasing their antibacterial and antibiofilm properties and inhibiting bacterial infections that cause white spot lesions and lead to periodontal disease.

Methods: Three concentrations of biologically synthesized AgNPs were used for coating NiTi wires. The shape, size, and charge of the AgNPs were determined. Six groups of 0.016 × 0.022-inch NiTi orthodontic wires, each with six wires, were used; and coated with AgNPs and nanocomposites. The antimicrobial and antibiofilm activities of these coated wires were tested against normal flora and multidrug-resistant bacteria (Gram-positive and Gram-negative bacterial isolates). The surface topography, roughness, elemental percentile, and ion release were characterized.

Results: AgNPs and nanocomposite coated NiTi wires showed significant antimicrobial and antibiofilm activities. The chitosan-silver nanocomposite (CS-Ag) coated wires had the greatest bacterial growth inhibition against both Gram-positive and Gram-negative bacteria. The surface roughness of the coated wires was significantly reduced, impacting the surface topography and with recorded low Ni and Ag ion release rates.

Conclusions: NiTi orthodontic wires coated with AgNPs, and nanocomposites have shown increased antimicrobial and antibiofilm activities, with decreased surface roughness, friction resistance and limited- metal ion release.

Background: Existing studies predominantly focused on the relationship between periodontitis and type 2 diabetes mellitus (T2DM), with limited data on the association between periodontitis and type 1 diabetes mellitus (T1DM). This study aimed to examine the impact of T1DM and periodontitis on the subgingival microbiome and levels of advanced glycation end-products (AGEs).

Methods: Samples were collected from four groups: T1DM, periodontitis (P), T1DM with periodontitis (DP), and periodontally and systemically healthy controls (Control). Subgingival microbiome composition and AGE levels were assessed using 16S rRNA gene sequencing and enzyme-linked immunosorbent assay (ELISA), respectively. Correlations between clinical indexes, microbiome composition, and AGEs were analyzed using Spearman correlation coefficient.

Results: Alpha and beta diversity analyses revealed significant differences in bacterial diversity between the DP group and other groups. Linear discriminant analysis effect size (LEfSe) analysis identified specific bacteria influencing each group: Acinetobacter, Leptotrichia, Raoultibacter, and Veillonella in the Control group; Tannerella, Porphyromonas, Filifactor, and Treponema in the P group; and Lactobacillales in T1DM individuals. Prevotella and Selenomonas were notably influential in the DP group. PICRUSt2 analysis showed pathways alterations were concentrated in cell motility, translation, cell growth and death and metabolism in the DP and P groups. Spearman correlation analysis indicated a positive correlation between AGEs and periodontitis or diabetes-related parameters and AGEs were positively correlated with Haemophilus and Arachnia.

Conclusions: The findings suggested that the composition and function of the subgingival microbiome in the P group with or without T1DM were significantly different. Additionally, AGEs were involved in the development of periodontitis even in absence of hyperglycemia.

Background: Clear thermoplastic materials are used in a variety of oral appliances. In some situations, patients may wear clear thermoplastic appliances while eating. However, the effect of wearing clear thermoplastic appliances on chewing efficiency is unknown. This study aimed to evaluate the differences in masticatory function between chewing with and without wearing clear thermoplastic retainers over a 6-month period, and its associated factors.

Methods: Thirty patients who received upper and lower clear retainers after debonding fixed appliances were examined for objective and subjective masticatory function at retainer delivery (T0), 3-month (T1), and 6-month follow-ups (T2) in two conditions: with and without wearing their retainers while chewing. The objective method used multiple sieves reported as the median particle size (MPS). The food intake ability (FIA) test served as the subjective method. Paired t-test was used to compare the outcomes between chewing with and without retainers at each evaluation time point. Repeated measures ANOVA followed by the Bonferroni post-hoc test was used to compare the outcomes between the three evaluating time points. Multivariable linear regression analysis was performed to assess whether age, sex, and extraction/non-extraction was associated with these effects.

Results: The MPS was significantly greater when chewing with retainers compared with chewing without them at T0 (P < 0.05), however, it was not significantly greater at T1 and T2 (P > 0.05). The MPS with and without the retainers tend to decrease between T0, T1 and T2. In particular, the MPS while chewing with retainers significantly decreased between T0 and T1. The total FIA score and FIA subscores for hard and soft food were significantly lower when eating with retainers at T0 (P < 0.05), however, all FIA scores when eating without retainers did not significantly change between T0, T1, and T2. No significantly associated factors were identified.

Conclusions: Wearing clear retainers while chewing decreases objective and subjective masticatory function immediately after completing orthodontic treatment. However, this significantly improved to levels comparable to chewing without retainers after a 3-month follow-up. Age, sex, and extraction/non-extraction treatment were not associated with the difference in masticatory function while chewing with and without wearing the retainers.

Background and aim: The burden of orofacial clefts (OFCs) has declined globally except in sub-Saharan Africa, with a great disease burden in North Africa. Children with OFCs have a high risk of malnutrition, and African countries have some of the highest malnutrition rates. This scoping review assessed the status of research on OFCs and nutrition and feeding among children living in African countries.

Methods: We followed the Joanna Briggs Institute guidelines for conducting scoping reviews. We searched eleven databases for articles on malnutrition and feeding among children with OFCs living in African countries. No restriction was done by type of study or publication date. Books, book chapters, and reviews were excluded. Only publications in English language were included. We extracted information about the publication year, study design, setting, location, participants' age, data collection methods, international collaboration, and funding. We classified articles into studies assessing (1) the impact of nutritional deficiencies during pregnancy on OFCs, (2) the impact of OFCs on malnutrition, (3) feeding problems in children with OFCs, and (4) the impact of nutritional status on OFCs repair outcomes. We calculated frequencies and used bar charts and a map.

Results: Out of 208 search results, 36 were duplicates, and 25 eventually fit the inclusion criteria, with 52% retrieved from Google Scholar. About 80% of the studies were from four countries: Nigeria, South Africa, Ghana, and Uganda; 72% were hospital-based and 52% were cross-sectional. The most frequent data collection method was clinical examination and questionnaires. Most studies focused on feeding problems in children with OFCs (44%) and the impact of OFCs on malnutrition (32%). International collaboration was observed in six studies, with one study showing South-South collaboration. Only two studies were funded.

Conclusions: There is a predominance of under-funded descriptive research not indexed by international databases. Minimal research has been directed to population-level OFC preventive programs in primary healthcare settings and assessing interventions supporting children with OFCs. A research agenda is needed to prioritize research needs and secure funds to support South-South collaboration to address the nutrition and feeding-related problems associated with OFCs.

Aim: to assess and compare the effect of mid-root perforation repair using Biodentine and Portland cement in single-rooted endodontically treated mandibular premolars in terms of stress distribution using finite element analysis (FEA) and fracture resistance test.

Methods: In the FEA, an extracted human mandibular premolar tooth was scanned using cone beam computed tomography, and a 3-dimensional (3D) solid model was created. A sound tooth model (ST), an endodontically treated model (ET), an instrumented and mid-root perforated and repaired by Biodentine model (BM), and perforated and repaired by Portland cement model (PCM) were the 4 models simulated. A vertical force of 300 N on the occlusal plane was applied. Evaluation of von Mises stress distribution and maximum displacement were investigated. In the fracture resistance in vitro study, 28 extracted premolars were selected and randomized into 4 groups, (n = 7), (A) is the negative control intact group, (B) is the positive control of endodontically treated group, (C) is mid-root perforated and repaired by Biodentine group and (D) is mid-root perforated and repaired by Portland cement. All Teeth were instrumented except for group A, group B was obturated while groups C and D were instrumented, perforated, repaired, and obturated. All groups were restored coronally except group A. Fracture force was measured; subsequently, the fracture repairability was evaluated. Finally, the data were statistically evaluated using one-way analysis of variance (ANOVA); the significance level was set at P ≤ 0.05 and the repairability of teeth after fracture was correlated to the maximum loading using Pearson's coefficient tests.

Results: In FEA, Maximum von Mises stress was descending assorted as 121.1 MPa for ET, 115.6 MPa for BM and PCM, and 109 MPa for ST, and in the mid-root area or perforation site were 20 MPa for PCM, 16.17 MPa for BM, 10.16 MPa for ET and 8.1 MPa for ST while the Maximum Displacement was descending assorted as 0.0179 mm for ET, 0.0169 mm for BM and PCM and 0.0151 mm for ST. In the fracture resistance test, Group A showed higher fracture resistance than other groups significantly. There was a non-significant difference between Groups B, C, and D. There was also an insignificant correlation between the maximum loading and the repairability of the tooth after fracture.

Conclusion: FEA and fracture resistance test showed that the 2 repair materials are acceptable and recommended in iatrogenic mid-root perforation.

Background: Using infection control barriers (ICBs) on light curing units (LCUs) became mandatory to achieve proper infection control measures without jeopardizing the integrity of the restorations, especially at deeper layers. This study explored the effect of two ICBs on the irradiance of the LCU, as well as the degree of conversion (DC) and flexural strength (FS) of two types of bulk-fill composites. Water vapor permeability (WVP) of both barriers was also assessed to evaluate the capability of such barriers to prevent transmission of blood and saliva droplets and aerosols.

Methods: Two bulk-fill composites (X-tra fil and Tetric N- ceram) and two ICBs (Pinnacle Cure sleeve and Sanita wrapping film) were used in this study. Light irradiance was recorded per experimental condition using spectroradiometer. For DC and FS, specimens of 4 mm thickness were prepared. Each specimen was composed of two separable upper and lower layers of thickness 2 mm. DC and FS were measured using Infra-red spectroscopy and three-point loading test respectively. WVP was investigated using the cup method. Means and standard deviations were calculated, and the data were statistically analyzed using factorial analysis of variance test (α = 0.05).

Results: Light irradiance showed highest values using no ICBs and lowest values using Pinnacle curing sleeve. Both bulk-fill composites showed higher DC mean values without ICBs and when using Sanita wrapping film for both upper and lower layers of the specimens compared to Pinnacle curing sleeve. The upper layers of composite specimens showed higher DC compared to lower layers for all experimental conditions. Both ICBs had no adverse effect on FS of both composites' upper layers. Pinnacle sleeve significantly reduced FS of both composites' lower layers. X-tra fil showed higher DC and FS compared to Tetric N-Ceram for all experimental conditions. Regarding WVP; the wrapping film showed higher WVP compared to the curing sleeve.

Conclusions: Sanita wrapping film can be used as a successful ICB, without jeopardizing the concept of bulk-fill composites. Pinnacle cure sleeve can be considered an effective ICB, however its influence on properties and serviceability of bulk-fill composites remains questionable.

Periapical periodontitis may manifest as a radiographic lesion radiographically. Periapical lesions are amongst the most common dental pathologies that present as periapical radiolucencies on panoramic radiographs. The objective of this research is to assess the diagnostic accuracy of an artificial intelligence (AI) model based on U²-Net architecture in the detection of periapical lesions on dental panoramic radiographs and to determine whether they can be useful in aiding clinicians with diagnosis of periapical lesions and improving their clinical workflow. 400 panoramic radiographs that included at least one periapical radiolucency were selected retrospectively. 780 periapical radiolucencies in these anonymized radiographs were manually labeled by two independent examiners. These radiographs were later used to train the AI model based on U²-Net architecture trained using a deep supervision algorithm. An AI model based on the U²-Net architecture was implemented. The model achieved a dice score of 0.8 on the validation set and precision, recall, and F1-score of 0.82, 0.77, and 0.8 respectively on the test set. This study has shown that an AI model based on U²-Net architecture can accurately diagnose periapical lesions on panoramic radiographs. The research provides evidence that AI-based models have promising applications as adjunct tools for dentists in diagnosing periapical radiolucencies and procedure planning. Further studies with larger data sets would be required to improve the diagnostic accuracy of AI-based detection models.