Polymerization-Induced Self-Assembly to Produce Prodrug Nanoparticles with Reduction-Responsive Camptothecin Release and pH-Responsive Charge-Reversible Property.

Polymerization-induced self-assembly has been demonstrated to be a powerful strategy for fabricating polymeric nanoparticles in the last two decades. However, the stringent requirements for the monomers greatly limit the chemical versatility of PISA-based functional nanoparticles and expanding the monomer family of PISA is still highly desirable. Herein, a camptothecin analogue (CPTM) is first used as the monomer in PISA. Prodrug nanoparticles with reduction-responsive camptothecin release behavior are fabricated at 10% solid concentration (100 mg g-1 ). Poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA) and poly(2-(diethylamino)ethyl methacrylate) (PDEAEMA) are used as the macro RAFT agents to comediate the RAFT dispersion polymerization of CPTM in ethanol to produce the PHPMA/PDEAEMA-stabilized nanoparticles. The PDEAEMA chains become hydrophobic and are in the collapsed state at physiological pH values. In contrast, in the vicinity of an acidic tumor, the tertiary amine groups of PDEAEMA chains are rapidly protonated, leading to fast hydrophobic-hydrophilic transitions and charge reversal. Such fast charge-reversal results in enhanced cancer cell internalization of the prodrug nanoparticles, thus achieving superior anticancer efficacy.

Polymerization-Induced Self-Assembly of Functionalized Block Copolymer Nanoparticles and Their Application in Drug Delivery.

Drug delivery systems (DDS) based on functionalized polymeric nanoparticles have attracted considerable attention. Although great advances have been reported in the past decades, the fabrication efficiency and reproducibility of polymeric nanoparticles are barely satisfactory due to the intrinsic limitations of the traditional self-assembly method, which severely prevent further applications of the intelligent DDS. In the last decade, a new self-assembly method, which is usually called polymerization-induced self-assembly (PISA), has become a powerful strategy for the fabrication of the polymeric nanoparticles with bespoke morphology. The PISA strategy efficiently simplifies the fabrication of polymeric nanoparticles (combination of the polymerization and self-assembly in one pot) and allows the fabrication of polymeric nanoparticles at a relatively high concentration (up to 50 wt%), making it realistic for large-scale production of polymeric nanoparticles. In this review, the developments of PISA-based polymeric nanoparticles for drug delivery are discussed.

Cone-Beam Computed Tomography Analysis of the Prevalence, Length, and Passage of the Anterior Loop of the Mandibular Canal.

When placing implants in the anterior mandible, it is important to avoid damaging the mandibular nerve and its terminal extensions. The objective of this study was to determine the prevalence, length, and passage of the anterior loop of the mandibular canal, as well as the quantity of alveolar bone that is coronal to the canal, to help with implant placement in the anterior mandible. Cone-beam computerized tomography (CBCT) scans of 124 patients with 248 hemi-sections were evaluated. Anterior loop prevalence was determined using reconstructed panoramic and cross-sectional views; length was measured as the distance between the most mesial aspect of the mental foramen to the most mesial aspect of the anterior loop on cross-sectional views. The bucco-lingual position of the anterior loop inside the mandible and the apico-coronal dimensions of the alveolar bone above it were measured on cross-sectional views to determine the passage of the anterior loop and the bone available coronally, respectively. The effects of sex, age, side, and dentate status on the prevalence and length of the anterior loop were analyzed statistically. Prevalence of the anterior loop at the patient and hemi-section levels was 25% and 24%, respectively, and its median length was 1.63 mm (range, 0.52-3.92 mm). The anterior loop was apical to the mental foramen and mostly located within the buccal or middle one-third of the alveolar ridge, with an average height of coronal alveolar bone of 17.12 mm. Sex, age, side, and dentate status did not affect anterior loop prevalence and length. In conclusion, because of great variation, a case-by-case CBCT evaluation of the anterior loop is necessary before placing implants in the anterior mandible.

A retrospective study on molar furcation assessment via clinical detection, intraoral radiography and cone beam computed tomography.

BACKGROUND: Accurate determination of bone loss at the molar furcation region by clinical detection and intraoral radiograph is challenging in many instances. Cone beam computed tomography (CBCT) is expected to open a new horizon in periodontal assessment. The purpose of this study was to compare and correlate accuracy of molar furcation assessment via clinical detection, intraoral radiography and CBCT images. METHODS: Eighty-three patients with chronic periodontitis who had existing CBCT scans were included. Furcation involvement was assessed on maxillary and mandibular first molars. Periodontal charts (modified Glickman's classification), intraoral (periapical and/or bitewing) radiographs (recorded as presence or absence) and axial CBCT reconstructions were used to evaluate furcation involvement on buccal and palatal/lingual sites. The correlation of furcation assessment by the three methods was evaluated by Pearson analysis. RESULTS: There were significant correlations (p < 0.05) between clinical detection and intraoral radiography, clinical detection and CBCT, as well as intraoral radiography and CBCT at all the measured sites (r values range between 0.230 to 0.644). CBCT generally exhibited higher correlation with clinical detection relative to intraoral radiography, especially at distal palatal side of maxillary first molar (p < 0.05). In addition, CBCT provided more accurate assessment, with bone loss measurement up to 2 decimals in millimeters, whereas clinical detection had 3 classes and the intraoral radiographs usually only detected the presence of furcation involvement in Glickman Class 2 and 3. CONCLUSIONS: This study validates that CBCT is a valuable tool in molar furcation assessment in addition to clinical detection and intraoral radiography.

Efficient Fabrication of Photosensitive Polymeric Nano-objects via an Ingenious Formulation of RAFT Dispersion Polymerization and Their Application for Drug Delivery.

An ingenious formulation of RAFT dispersion polymerization based on photosensitive monomers of 2-nitrobenzyl methacrylate (NBMA) and 7-(2-methacryloyloxy-ethoxy)-4-methyl-coumarin (CMA) is reported herein. Various morphologies, such as spherical micelle, nanoworm, lamella, and vesicle, are fabricated at up to 20% solids content. Photoinduced cleavage of the NBMA moieties and dimerization of the coumarin moieties are simultaneously triggered upon UV (365 nm) irradiation. The former endows the cores of the nano-objects with abundant carboxyl groups, resulting in the transformation of the hydrophobic cores to hydrophilic ones. The latter induces the core-cross-linking of the nano-objects, which endows the nano-objects with enhanced structural stability and prevents the nanoparticle-to-unimer disassembly. The resultant nano-objects exhibit superior structural stability and excellent performances for drug delivery, including high drug loadings, pH-stimuli release, and high-efficient endosomal escape.

Fabrication of Reductive-Responsive Prodrug Nanoparticles with Superior Structural Stability by Polymerization-Induced Self-Assembly and Functional Nanoscopic Platform for Drug Delivery.

A highly efficient strategy, polymerization-induced self-assembly (PISA) for fabrication of the polymeric drug delivery systems in cancer chemotherapy is reported. Diblock prodrug copolymer, PEG-b-P(MEO2MA-co-CPTM) was used as the macro-RAFT agent to fabricate prodrug nanoparticles through PISA. The advantages of fabricating intelligent drug delivery system via this approach are as following: (1) Simultaneous fulfillment of polymerization, self-assembly, and drug encapsulation in one-pot at relatively high concentration (100 mg/mL); (2) Almost complete monomer conversion allows direct application of the resultant prodrug nanoparticles without further purification; (3) Robust structures of the resultant prodrug nanoparticles, because the cross-linker was used as the comonomer, resulted in core-cross-linking simultaneously with the formation of the prodrug nanoparticles; (4) The drug content in the resultant prodrug nanoparticles can be accurately modulated just via adjusting the feed molar ratio of MEO2MA/CPTM in the synthesis of PEG-b-P(MEO2MA-co-CPTM). The prodrug nanoparticles with similar diameters but various drug contents were obtained using different prodrug macro-CTA. In consideration of the long-term biological toxicity, the prodrug nanoparticles with higher drug content exhibit more excellent anticancer efficiency due to that lower dosage of them are enough for effectively killing HeLa cells.

PDGFRß+/c-kit+ pulp cells are odontoblastic progenitors capable of producing dentin-like structure in vitro and in vivo.

BACKGROUND: Successful pulp regeneration depends on identification of pulp stem cells capable of differentiation under odontoblastic lineage and producing pulp-dentinal like structure. Recent studies demonstrate that platelet-derived growth factor (PDGF) plays an important role in damage repair and tissue regeneration. The aim of this study was to identify a subpopulation of dental pulp cells responsive to PDGF and with dentin regeneration potential. METHODS: Pulp tissues were isolated from 12 freshly extracted human impacted third molars. Pulp cells were sorted by their expression of PDGFRß and stem cell marker genes via flow cytometry. For the selected cells, proliferation was analyzed by a colorimetric cell proliferation assay, differentiation was assessed by real time PCR detection the expression of odontoblast marker genes, and mineralization was evaluated by Alizarin Red S staining. GFP marked PDGFRß+/c-kit+ pulp cells were transplanted into emptied root canals of nude rat lower left incisors. Pulp-dentinal regeneration was examined by immunohistochemistry. RESULTS: PDGFRß+/c-kit+ pulp cells proliferated significantly faster than whole pulp cells. In mineralization media, PDGFRß+/c-kit+ pulp cells were able to develop under odontoblastic linage as demonstrated by a progressively increased expression of DMP1, DSPP, and osteocalcin. BMP2 seemed to enhance whereas PDGF-BB seemed to inhibit odontoblastic differentiation and mineralization of PDGFRß+/c-kit+ pulp cells. In vivo root canal transplantation study revealed globular dentin and pulp-like tissue formation by PDGFRß+/c-kit+ cells. CONCLUSIONS: PDGFRß+/c-kit+ pulp cells appear to have pulp stem cell potential capable of producing dentinal like structure in vitro and in vivo.

Cone Beam Computed Tomography of mandibular bone density in non-diabetic vs. diabetic populations.

BACKGROUND: The successful placement of dental implant largely depends on the properties of alveolar bone at the recipient site. Systemic conditions such as diabetes mellitus could impair bone quality and compromise implant treatment. However, limited information in this area exists so far. The objective of the study is to use cone beam computed tomography (CBCT) to assess mandibular bone mineral density (BMD) in diabetic and non-diabetic populations. METHODS: The patients who had CBCT scans in the school from 2011-2015 were screened, and 14 diabetic and 14 non- diabetic patients with matched age, gender, and ethnicity were recruited. BMD was measured on reconstructed CBCT sagittal views at 7 mm2 rectangular areas on 6 sites for each patient. For cortical bone, BMD was measured at the inferior border of mandible in the midline and between the first and second premolar bilaterally. For cancellous bone, BMD was measured in the midline of mandible halfway between the lingual foramen/canal and the inferior border of mandible, and at the premolar area halfway between the mandibular canal and the inferior border of mandible bilaterally. For diabetic patients, the glycosylated hemoglobin (HbAlc) values were obtained after informed consent. Statistical significant difference was set at p <0.05. The correlation between BMD and the age, gender, and HbAlc value of the patients was analyzed. An institutional IRB approval was obtained for the study. RESULTS: Diabetic patients had significantly lower cancellous BMD than non-diabetic subjects in the posterior mandibles (367 vs. 430, p<0.05). For both groups, cancellous BMD in the posterior mandible was significantly lower than that of anterior mandible. CONCLUSIONS: Diabetic patients have decreased BMD in the posterior mandible which could adversely affect implant placement at these areas.

Formation of Hexagonally Packed Hollow Hoops and Morphology Transition in RAFT Ethanol Dispersion Polymerization.

Similar to the traditional self-assembly strategy, polymerization induced self-assembly and reorganization (PISR) can produce a myriad of polymeric morphologies through morphology transitions. Besides the chain length ratio (R) of the hydrophobic to the hydrophilic blocks, the chain mobility in the intermediate nano-objects, which is a requisite for morphology transition, is a determining factor in the formation of the final morphology. Although various morphologies have been fabricated, hexagonally packed hollow hoops (HHHs) with highly ordered internal structure have not, to the best of our knowledge, been prepared by PISR. In this article, the fabrication of HHHs through morphology transition from large compound vesicles to HHHs is reported. HHHs with highly regular internal structure may have significance in theoretical research and practical applications of nanomaterials.

Anterior maxilla alveolar ridge dimension and morphology measurement by cone beam computerized tomography (CBCT) for immediate implant treatment planning.

BACKGROUND: Implants have been widely used to restore missing teeth. Limited information on applied anatomy at the anterior maxilla compromises the clinical outcome for implant placement in this region. In the current study, Cone Beam Computerized Tomography (CBCT) was used to measure alveolar ridge and buccal undercut dimension at the anterior maxilla to help develop treatment planning for immediate implant placement. METHODS: CBCT scans were screened to include 51 subjects with full dentition at right maxilla. Measurements were taken at the cross sectional views in the middle of the maxillary right central incisor, lateral incisor, and canine regions. Alveolar height was measured from the alveolar crest to floor of nasal fossa. Alveolar width was measured from the buccal to palatal cortical plate at the coronal, middle, and apical third of the distance from the alveolar crest to floor of the nasal fossa. Buccal undercut location was measured from where the buccal cortical plate started dipping to a line extending at the alveolar crest that was perpendicular to the long axis of the alveolar ridge. The buccal undercut depth was measured from the deepest point of the undercut at the buccal plate to a line tangent to the buccal plate paralleling the long axis of ridge. RESULTS: Alveolar width increased from coronal to apical direction for each tooth. Mean alveolar widths (mm) were: central incisor, 9.55; lateral incisor, 8.30; canine, 9.62. The lateral incisor had a significantly smaller alveolar width than the other anterior teeth. No significant difference in ridge height was noted among the teeth. Undercut locations from the alveolar crest (mm) were: central incisor, 5.84; lateral incisor, 3.59; canine, 5.11. Undercut depths (mm) were: central incisor, 0.76; lateral incisor, 0.87; canine, 0.73. The percentages of teeth with buccal undercuts were: central incisor, 41%, lateral incisor, 77%, and canine 33%. Male demonstrate significant larger ridge width compared with females for all three teeth. CONCLUSIONS: At anterior maxilla, the lateral incisor has the thinnest alveolar bone, and most frequently exhibits a buccal undercut which is the closest to alveolar ridge compared with other maxillary anterior teeth.

Porphyromonas gingivalis infection increases osteoclastic bone resorption and osteoblastic bone formation in a periodontitis mouse model.

BACKGROUND: Porphyromonas gingivalis has been shown to invade osteoblasts and inhibit their differentiation and mineralization in vitro. However, it is unclear if P. gingivalis can invade osteoblasts in vivo and how this would affect alveolar osteoblast/osteoclast dynamics. This study aims to answer these questions using a periodontitis mouse model under repetitive P. gingivalis inoculations. METHODS: For 3-month-old BALB/cByJ female mice, 10(9) CFU of P. gingivalis were inoculated onto the gingival margin of maxillary molars 4 times at 2-day intervals. After 2 weeks, another 4 inoculations at 2-day intervals were applied. Calcein was injected 7 and 2 days before sacrificing animals to label the newly formed bone. Four weeks after final inoculation, mice were sacrificed and maxilla collected. Immunohistochemistry, micro-CT, and bone histomorphometry were performed on the specimens. Sham infection with only vehicle was the control. RESULTS: P. gingivalis was found to invade gingival epithelia, periodontal ligament fibroblasts, and alveolar osteoblasts. Micro-CT showed alveolar bone resorption and significant reduction of bone mineral density and content in the infected mice compared to the controls. Bone histomorphometry showed a decrease in osteoblasts, an increase in osteoclasts and bone resorption, and a surprisingly increased osteoblastic bone formation in the infected mice compared to the controls. CONCLUSIONS: P. gingivalis invades alveolar osteoblasts in the periodontitis mouse model and cause alveolar bone loss. Although P. gingivalis appears to suppress osteoblast pool and enhance osteoclastic bone resorption, the bone formation capacity is temporarily elevated in the infected mice, possibly via some anti-microbial compensational mechanisms.

[Modification by wheat germ agglutinin delays the ocular elimination of liposome].

The purpose of this study is to explore the feasibility of wheat germ agglutinin (WGA) modified liposome as a vehicle for ophthalmic administration. Liposome loaded with 5-carboxyfluorescein (FAM) was prepared by lipid film hydration method. WGA was thiolated and then conjugated to the surface of the liposome via polyethylene glycol linker to constitute the WGA-modified and FAM-loaded liposome (WGA-LS/FAM). The amount of thiol groups on each WGA molecule was determined, and the bioactivity of WGA was estimated after it was modified to the surface of liposome. The physical and chemical features of the WGA-modified liposome were characterized and the ocular bioadhesive performance was evaluated in rats. The result showed that each thiolated WGA molecule was conjugated with 1.32 thiol groups. WGA-LS/FAM had a mean size of (97.40 +/- 1.39) nm, with a polydispersity index of 0.23 +/- 0.01. The entrapment efficacy of FAM was about (2.95 +/- 0.21)%, and only 4% of FAM leaked out of the liposome in 24 h. Erythrocyte agglutination test indicated that after modification WGA preserved the binding activity to glycoprotein. The in vivo ocular elimination of WGA-LS/FAM fitted first-order kinetics, and the elimination rate was significantly slower than that of the unmodified liposome, demonstrating WGA-modified liposome is bioadhesive and suitable for ophthalmic administration.

Classification of mandibular molar furcation involvement in periapical radiographs by deep learning.

Purpose: The purpose of this study was to classify mandibular molar furcation involvement (FI) in periapical radiographs using a deep learning algorithm. Materials and Methods: Full mouth series taken at East Carolina University School of Dental Medicine from 2011-2023 were screened. Diagnostic-quality mandibular premolar and molar periapical radiographs with healthy or FI mandibular molars were included. The radiographs were cropped into individual molar images, annotated as " healthy" or " FI," and divided into training, validation, and testing datasets. The images were preprocessed by PyTorch transformations. ResNet-18, a convolutional neural network model, was refined using the PyTorch deep learning framework for the specific imaging classification task. CrossEntropyLoss and the AdamW optimizer were employed for loss function training and optimizing the learning rate, respectively. The images were loaded by PyTorch DataLoader for efficiency. The performance of ResNet-18 algorithm was evaluated with multiple metrics, including training and validation losses, confusion matrix, accuracy, sensitivity, specificity, the receiver operating characteristic (ROC) curve, and the area under the ROC curve. Results: After adequate training, ResNet-18 classified healthy vs. FI molars in the testing set with an accuracy of 96.47%, indicating its suitability for image classification. Conclusion: The deep learning algorithm developed in this study was shown to be promising for classifying mandibular molar FI. It could serve as a valuable supplemental tool for detecting and managing periodontal diseases.

Integrin α5ß1-fimbriae binding and actin rearrangement are essential for Porphyromonas gingivalis invasion of osteoblasts and subsequent activation of the JNK pathway.

BACKGROUND: Chronic periodontitis is an infectious disease of the periodontium, which includes the gingival epithelium, periodontal ligament and alveolar bone. The signature clinical feature of periodontitis is resorption of alveolar bone and subsequent tooth loss. The Gram-negative oral anaerobe, Porphyromonas gingivalis, is strongly associated with periodontitis, and it has been shown previously that P. gingivalis is capable of invading osteoblasts in a dose- and time-dependent manner resulting in inhibition of osteoblast differentiation and mineralization in vitro. It is not yet clear which receptors and cytoskeletal components mediate the invasive process, nor how the signaling pathways and viability of osteoblasts are affected by bacterial internalization. This study aimed to investigate these issues using an in vitro model system involving the inoculation of P. gingivalis ATCC 33277 into primary osteoblast cultures. RESULTS: It was found that binding between P. gingivalis fimbriae and integrin α5ß1 on osteoblasts, and subsequent peripheral condensation of actin, are essential for entry of P. gingivalis into osteoblasts. The JNK pathway was activated in invaded osteoblasts, and apoptosis was induced by repeated infections. CONCLUSIONS: These observations indicate that P. gingivalis manipulates osteoblast function to promote its initial intracellular persistence by prolonging the host cell life span prior to its intercellular dissemination via host cell lysis. The identification of molecules critical to the interaction between P. gingivalis and osteoblasts will facilitate the development of new therapeutic strategies for the prevention of periodontal bone loss.

Extracolonic manifestations of Gardner syndrome: A case report.

Gardner syndrome has head and neck manifestations that may be recognized during dental visits. Features such as multiple gnathic osteomas, impacted supernumerary teeth, and multiple foci of idiopathic osteosclerosis can be easily identified on dental radiographs, prompting the clinician to refer the patient for further investigation. A dental examination and routine radiographs play a vital role in revealing the extracolonic presentation of Gardner syndrome, which facilitates timely screening and detection of colorectal cancer and other malignancies associated with this condition. This report discusses the case of a 50-year-old Caucasian man who presented with a hard swelling of the left angle of the mandible and was diagnosed with Gardner syndrome based on abnormal findings from an oral examination, dental imaging, and medical and family history.

[Poly(arginine)8 enhanced intestinal absorption of insulin-loaded nanoparticles].

The purpose of this study is to investigate the feasibility of poly(arginine)8 (R8) modified poly(lactic-co-glycolic acid) (PLGA) nanoparticles as a carrier for the oral delivery of insulin. Insulin-loaded PLGA nanoparticle (INS-NP) was prepared by a double emulsion-solvent evaporation method, and R8 was subsequently conjugated to the surface of the INS-NP via polyethylene glycol bridge (R8-INS-NP). The physical and chemical features of the nanoparticles were characterized, and insulin release was determined in vitro. The pharmacokinetics and pharmacodynamics were evaluated by in situ absorption study with the intestinal loop of rats. The blood glucose level was determined by glucose oxidize method and the serum insulin concentration was determined by radioimmunoassay (RIA). The mean diameter of INS-NP was (179.0 +/- 5.2) nm and the polydispersity index was 0.152 +/- 0.042, while the entrapment efficiency was (29.10 +/- 2.59) %. The in vitro release behavior of insulin showed an initial burst effect followed by a stage of slow release. After administrating 10 U x kg(-1) insulin to rats, R8-INS-NPs decreased the plasma glucose level much lower than INS-NPs, meanwhile, D-form R8 substantially enhanced intestinal absorption of insulin much more than L-form R8. Compared to subcutaneous injection, the relative bioavailabilities of insulin were 0.52%, 4.78%, 8.39%, and the pharmacological bioavailabilities were 2.07%, 3.90%, 8.24%, separately. The R8-modified nanoparticles promoted the intestinal absorption of insulin, which might be a potential approach for oral delivery of peptide, protein and even other hydrophilic macromolecules in the future.

Comparison of technique errors of intraoral radiographs taken on film v photostimulable phosphor (PSP) plates.

OBJECTIVE: The objective of this study was to compare the technical errors of intraoral radiographs exposed on film v photostimulable phosphor (PSP) plates. METHODS: The intraoral radiographic images exposed on phantoms from preclinical practical exams of dental and dental hygiene students were used. Each exam consisted of 10 designated periapical and bitewing views. A total of 107 film sets and 122 PSP sets were evaluated for technique errors, including placement, elongation, foreshortening, overlapping, cone cut, receptor bending, density, mounting, dot in apical area, and others. Some errors were further subcategorized as minor, major, or remake depending on the severity. The percentages of radiographs with various errors were compared between film and PSP by the Fisher's Exact Test. RESULTS: Compared with film, there was significantly less PSP foreshortening, elongation, and bending errors, but significantly more placement and overlapping errors. Using a wrong sized receptor due to the similarity of the color of the package sleeves is a unique PSP error. CONCLUSIONS: Optimum image quality is attainable with PSP plates as well as film. When switching from film to a PSP digital environment, more emphasis is necessary for placing the PSP plates, especially those with excessive packet edge, and then correcting the corresponding angulation for the beam alignment. Better design for improving intraoral visibility and easy identification of different sized PSP will improve the clinician's technical performance with this receptor.

Correlation Analysis between Airway Volume and Risk of Sleep Apnea/Periodontitis.

Objectives: Sleep apnea and periodontitis have high incidences in general population. They share common risk factors such as obesity, smoking, and aging. As cone-beam computed tomography becomes popular in dentistry, airway analysis is very accessible to dentists. However, not many studies have investigated the correlations between airway volume and risk of sleep apnea and periodontitis. The purpose of this retrospective study was to investigate the association between airway volume and the occurrence of sleep apnea and periodontitis. Material and Methods: Overall, 258 patients were enrolled (male: 118, female: 140, age from 13 to 88). axiUm® was used to collect demographical/physical information and the status of sleep apnea and periodontitis. Invivo™ software was utilized to measure airway dimensions. One-way ANOVA followed by Tukey's HSD post-hoc test and Pearson analysis were run to determine statistical difference in airway volumes among patients with various demographic and health status, and association of airway dimensions with their sleep apnea and periodontal conditions. Results: Sleep apnea patients had significantly higher body weight, body mass index, and significantly smaller airway compared to non-apnea patients (P < 0.05). Old age, male, and diabetes were found to be positively correlated with sleep apnea. No association between airway dimension and periodontal status was identified. Conclusions: Patients with high body mass index are at higher risk of developing constricted airway and sleep apnea. There appears to be no association between restricted airway and occurrence of periodontitis. Cone-beam computed tomography plays a critical role in identifying narrow airway and necessitating proper referral.

Comparison of CBCT Prescriptions among Different Campuses of East Carolina University School of Dental Medicine.

Objectives: East Carolina University School of Dental Medicine (ECU SoDM) has established a unique education model that delivers the dental curriculum through student rotations at community service learning centers (CSLCs) in underserved areas across North Carolina in their senior year. The objective of the study is to analyze the patient composition and CBCT prescription patterns at the main campus (Ross Hall) and eight CSLCs, to determine if students have comparable training at various sites. Methods: CBCTs taken at ECU SoDM in 2017-2021 were evaluated. One-way analysis of variance and the Wilcoxon Rank Sum Test were used to determine any differences in demographics, Medicaid coverage, and scan indications at various sites. Results: A total of 1444 patients were included, with an age range of 4-90 years old; male 685, female 758; 1130 non-Hispanic/Latino, 71 Hispanic/Latino. For races, Caucasian 1106, African-American 156, American Indian/Alaskan Native 32, Asian 18, mixed 13, other 73. For Medicaid, there are 75 with and 1369 without coverage. Ross Hall has the largest amount of patients at 537, followed by Davidson 218, Brunswick 189, and Lillington 169, with Elizabeth City being the least with 45 patients. The top four reasons for taking CBCTs were implants, endodontics, oral pathology, and 3rd molar assessment. There was no significant difference in the indications for CBCTs or Medicaid coverage, among various sites. Conclusions: The demographics, Medicaid coverage and CBCT prescription patterns were comparable among various sites. There was a site-related difference in the amount of scans taken, warranting the necessity to monitor CSLC rotation selections to ensure a consistent learning experience.

Evaluation of radiation exposure with Tru-Align intraoral rectangular collimation system using OSL dosimeters.

A pilot study to compare radiation exposure with the Tru-Align rectangular collimation system to round collimation exposures was undertaken. Radiation exposure at various points within the cross sections of the collimators and entrance, intraoral and exit dose measurements were measured using InLight OSL dosimeters. Overall dose reduction with the use of the rectangular collimation system was estimated by taking into account the ratios of collimator openings and the average radiation exposure at the measurement points. Use of the Tru-Align system resulted in an average radiation exposure within the perimeter of the projected outline of the rectangular collimator of 36.1 mR, compared to 148.5 mR with the round collimator. Our calculations indicate a dose reduction by a factor of approximately 3.2 in the case of the Tru-Align system compared to round collimation. The Tru-Align system was easy to use, but in some situations failed to allow Xray coverage of the entire surface of the image receptor, leading to cone cuts.