Browsing by Author "AlQallaf, Hawra"

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    Differential profiles of soluble and cellular toll like receptor (TLR)-2 and 4 in chronic periodontitis
    (PLOS, 2018-12-20) AlQallaf, Hawra; Hamada, Yusuke; Blanchard, Steven; Shin, Daniel; Gregory, Richard; Srinivasan, Mythily; Periodontology, School of Dentistry
    Chronic periodontitis is a common inflammatory disease initiated by a complex microbial biofilm and mediated by the host response causing destruction of the supporting tissues of the teeth. Host recognition of pathogens is mediated by toll-like receptors (TLRs) that bind conserved molecular patterns shared by large groups of microorganisms. The oral epithelial cells respond to most periodontopathic bacteria via TLR-2 and TLR-4. In addition to the membrane-associated receptors, soluble forms of TLR-2 (sTLR-2) and TLR-4 (sTLR-4) have been identified and are thought to play a regulatory role by binding microbial ligands. sTLR-2 has been shown to arise from ectodomain shedding of the extracellular domain of the membrane receptor and sTLR-4 is thought to be an alternate spliced form. Many studies have previously reported the presence of elevated numbers of viable exfoliated epithelial cells in the saliva of patients with chronic periodontitis. The objective of this study was to investigate the potential value of salivary sTLR-2 and sTLR-4 together with the paired epithelial cell-associated TLR-2/4 mRNA as diagnostic markers for chronic periodontitis. Unstimulated whole saliva was collected after obtaining informed consent from 40 individuals with either periodontitis or gingivitis. The sTLR-2 and sTLR4 in saliva was measured by enzyme-linked immunosorbent assay. The TLR-2 and TLR-4 transcript in the epithelial cells in saliva was measured by real time polymerase chain reaction. While levels of sTLR-2 exhibited an inverse correlation, sTLR-4 positively correlated with clinical parameters in the gingivitis cohort. Interestingly, both correlations were lost in the periodontitis cohort indicating a dysregulated host response. On the other hand, while the sTLR-2 and the paired epithelial cell associated TLR-2 mRNA exhibited a direct correlation (r2 = 0.62), that of sTLR4 and TLR-4 mRNA exhibited an inverse correlation (r2 = 0.53) in the periodontitis cohort. Collectively, assessments of salivary sTLR2 and sTLR4 together with the respective transcripts in the epithelial cells could provide clinically relevant markers of disease progression from gingivitis to periodontitis.
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    Differential profiles of soluble and cellular toll like receptor (TLR)-2 and 4 in chronic periodontitis
    (PLOS, 2018-12-20) AlQallaf, Hawra; Hamada, Yusuke; Blanchard, Steven; Shin, Daniel; Gregory, Richard; Srinivasan, Mythily; Periodontology, School of Dentistry
    Chronic periodontitis is a common inflammatory disease initiated by a complex microbial biofilm and mediated by the host response causing destruction of the supporting tissues of the teeth. Host recognition of pathogens is mediated by toll-like receptors (TLRs) that bind conserved molecular patterns shared by large groups of microorganisms. The oral epithelial cells respond to most periodontopathic bacteria via TLR-2 and TLR-4. In addition to the membrane-associated receptors, soluble forms of TLR-2 (sTLR-2) and TLR-4 (sTLR-4) have been identified and are thought to play a regulatory role by binding microbial ligands. sTLR-2 has been shown to arise from ectodomain shedding of the extracellular domain of the membrane receptor and sTLR-4 is thought to be an alternate spliced form. Many studies have previously reported the presence of elevated numbers of viable exfoliated epithelial cells in the saliva of patients with chronic periodontitis. The objective of this study was to investigate the potential value of salivary sTLR-2 and sTLR-4 together with the paired epithelial cell-associated TLR-2/4 mRNA as diagnostic markers for chronic periodontitis. Unstimulated whole saliva was collected after obtaining informed consent from 40 individuals with either periodontitis or gingivitis. The sTLR-2 and sTLR4 in saliva was measured by enzyme-linked immunosorbent assay. The TLR-2 and TLR-4 transcript in the epithelial cells in saliva was measured by real time polymerase chain reaction. While levels of sTLR-2 exhibited an inverse correlation, sTLR-4 positively correlated with clinical parameters in the gingivitis cohort. Interestingly, both correlations were lost in the periodontitis cohort indicating a dysregulated host response. On the other hand, while the sTLR-2 and the paired epithelial cell associated TLR-2 mRNA exhibited a direct correlation (r2 = 0.62), that of sTLR4 and TLR-4 mRNA exhibited an inverse correlation (r2 = 0.53) in the periodontitis cohort. Collectively, assessments of salivary sTLR2 and sTLR4 together with the respective transcripts in the epithelial cells could provide clinically relevant markers of disease progression from gingivitis to periodontitis.
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    Effects of IL-34 and anti-IL-34 neutralizing mAb on alveolar bone loss in a ligature-induced model of periodontitis
    (Wiley, 2023-10-30) Duarte, Carolina; Yamada, Chiaki; Ngala, Bidii; Garcia, Christopher; Akkaoui, Juliet; Birsa, Maxim; Ho, Anny; Nusbaum, Amilia; AlQallaf, Hawra; John, Vanchit; Movila, Alexandru; Periodontology, School of Dentistry
    Macrophage colony-stimulating factor (M-CSF) and interleukin-34 (IL-34) are ligands for the colony-stimulating factor-1 receptor (CSF-1r) expressed on the surface of monocyte/macrophage lineage cells. The importance of coordinated signaling between M-CSF/receptor activator of the nuclear factor kappa-Β ligand (RANKL) in physiological and pathological bone remodeling and alveolar bone loss in response to oral bacterial colonization is well established. However, our knowledge about the IL-34/RANKL signaling in periodontal bone loss remains limited. Recently published cohort studies have demonstrated that the expression patterns of IL-34 are dramatically elevated in gingival crevicular fluid collected from patients with periodontitis. Therefore, the present study aims to evaluate the effects of IL-34 on osteoclastogenesis in vitro and in experimental ligature-mediated model of periodontitis using male mice. Our initial in vitro study demonstrated increased RANKL-induced osteoclastogenesis of IL-34-primed osteoclast precursors (OCPs) compared to M-CSF-primed OCPs. Using an experimental model of ligature-mediated periodontitis, we further demonstrated elevated expression of IL-34 in periodontal lesions. In contrast, M-CSF levels were dramatically reduced in these periodontal lesions. Furthermore, local injections of mouse recombinant IL-34 protein significantly elevated cathepsin K activity, increased the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts and promoted alveolar bone loss in periodontitis lesions. In contrast, anti-IL-34 neutralizing monoclonal antibody significantly reduced the level of alveolar bone loss and the number of TRAP-positive osteoclasts in periodontitis lesions. No beneficial effects of locally injected anti-M-CSF neutralizing antibody were observed in periodontal lesions. This study illustrates the role of IL-34 in promoting alveolar bone loss in periodontal lesions and proposes the potential of anti-IL34 monoclonal antibody (mAb)-based therapeutic regimens to suppress alveolar bone loss in periodontitis lesions.
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    Evaluation of the accuracy of the soft tissue thickness measurements with three different methodologies: an in-vitro study
    (Wiley, 2022) Ferry, Katherine; AlQallaf, Hawra; Blanchard, Steven; Dutra, Vinicius; Lin, Wie-Shao; Hamada, Yusuke; Prosthodontics, School of Dentistry
    Background Soft tissue thickness (STT) influences esthetics, peri-implant, and periodontal health. Non-invasive methods of STT evaluation include cone-beam computed tomography (CBCT) with Digital Imaging and Communications in Medicine (DICOM) files and registration of DICOM files with an intraoral scan or Standard Tessellation Language (STL) files. This study compares three methodologies: bone sounding, DICOM data alone, and DICOM and STL registration to absolute histomorphologic values. Materials and Methods Five human maxillas, including teeth #s 6-11, provided 90 sites for analysis. For standardization, reference grooves were placed at the cervical margin and the long axis of each tooth. Direct measurements with a no. 25 K-file were completed at the facial soft tissues at 3.00, 5.00, and 7.00 mm from the apical marginal reference. Indirect measures were performed with implant planning software. Histological measurements were rendered with imaging software. One-way analysis of variance (ANOVA) was used to compare the three techniques for the differences from histologic measurements (α = .05). Results Seventy-two sites were included for final analysis. The overall mean histological STT (mSTT) was 0.73 ± 0.31 mm. Bone sounding overestimated mSTT, 0.22 ± 0.20mm (p<.001); whereas, DICOM alone underestimated mSTT, -0.23 ± 0.19 mm (p<.001). DICOM and STL registration had non-statistically significant differences, -0.04 ± 0.21mm (p = .429). Intraclass correlation coefficient (ICC) of DICOM and STL registration achieved the highest agreement with histology (ICC: 0.74). Conclusions DICOM and STL file registration had the highest agreement with histological STT supporting the use of DICOM and STL registration for the evaluation of soft tissue thickness.
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    Race to the Moon or the Bottom? Applications, Performance, and Ethical Considerations of Artificial Intelligence in Prosthodontics and Implant Dentistry
    (MDPI, 2024-12-27) Alfaraj, Amal; Nagai, Toshiki; AlQallaf, Hawra; Lin, Wei-Shao; Prosthodontics, School of Dentistry
    Objectives: This review aims to explore the applications of artificial intelligence (AI) in prosthodontics and implant dentistry, focusing on its performance outcomes and associated ethical concerns. Materials and Methods: Following the PRISMA guidelines, a search was conducted across databases such as PubMed, Medline, Web of Science, and Scopus. Studies published between January 2022 and May 2024, in English, were considered. The Population (P) included patients or extracted teeth with AI applications in prosthodontics and implant dentistry; the Intervention (I) was AI-based tools; the Comparison (C) was traditional methods, and the Outcome (O) involved AI performance outcomes and ethical considerations. The Newcastle-Ottawa Scale was used to assess the quality and risk of bias in the studies. Results: Out of 3420 initially identified articles, 18 met the inclusion criteria for AI applications in prosthodontics and implant dentistry. The review highlighted AI's significant role in improving diagnostic accuracy, treatment planning, and prosthesis design. AI models demonstrated high accuracy in classifying dental implants and predicting implant outcomes, although limitations were noted in data diversity and model generalizability. Regarding ethical issues, five studies identified concerns such as data privacy, system bias, and the potential replacement of human roles by AI. While patients generally viewed AI positively, dental professionals expressed hesitancy due to a lack of familiarity and regulatory guidelines, highlighting the need for better education and ethical frameworks. Conclusions: AI has the potential to revolutionize prosthodontics and implant dentistry by enhancing treatment accuracy and efficiency. However, there is a pressing need to address ethical issues through comprehensive training and the development of regulatory frameworks. Future research should focus on broadening AI applications and addressing the identified ethical concerns.
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    Using an existing surgical template as an aid for a virtual interocclusal record
    (Elsevier, 2020-09) Lin, Wei-Shao; AlQallaf, Hawra; Morton, Dean; Prosthodontics, School of Dentistry
    A satisfactory complete denture can be duplicated with acrylic resin to preserve the information on the patient’s occlusal vertical dimension, occlusal relationship, and tooth arrangement during preoperative planning for dental implant treatment.1 The duplicated denture can be used as a radiographic template, surgical template, and occlusally adapted custom tray.2 A dual scan protocol with the existing complete denture and additively manufactured surgical template (in the shape of a duplicated denture) is commonly used in contemporary static computer-aided implant surgery (s-CAIS). Occlusion with the opposing arch is often needed to properly position these surgical templates before the s-CAIS.3 As these surgical templates are designed and manufactured from the 3D volumetric data of the existing denture, preserving the interocclusal relationship, this technique allows the clinicians to use the surgical template as an aid to obtain a virtual interocclusal record during intraoral scanning. The acquired intraoral scan and virtual interocclusal record can be used for fabricating a computer-aided design and computer-aided manufacturing (CAD-CAM) implant prosthesis.