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Imaging Science in Dentistry Jun 2024Preoperative identification of the intraosseous posterior superior alveolar artery (PSAA) is critical when planning sinus surgery. This study was conducted to determine...
PURPOSE
Preoperative identification of the intraosseous posterior superior alveolar artery (PSAA) is critical when planning sinus surgery. This study was conducted to determine the distance between the cementoenamel junction and the PSAA, as well as to identify factors influencing the detection of the PSAA on cone-beam computed tomography (CBCT).
MATERIALS AND METHODS
In total, 254 CBCT scans of maxillary sinuses, acquired with 2 different scanners, were examined to identify the PSAA. The distance from the cementoenamel junction (CEJ) to the PSAA was recorded at each maxillary posterior tooth position. Binomial logistic regression and multiple linear regression were employed to evaluate the effects of scanner type, CBCT parameters, sex, and age on PSAA detection and CEJ-PSAA distance, respectively. -values less than 0.05 were considered to indicate statistical significance.
RESULTS
The mean CEJ-PSAA distances at the second molar, first molar, second premolar, and first premolar positions were 17.0±4.0 mm, 21.8±4.1 mm, 19.5±4.7 mm, and 19.9±4.9 mm for scanner 1, respectively, and 17.3±3.5 mm, 16.9±4.3 mm, 18.5±4.1 mm, and 18.4±4.3 mm for scanner 2. No independent variable significantly influenced PSAA detection. However, tooth position (b=-0.67, <0.05) and scanner type (b=-1.3, <0.05) were significant predictors of CEJ-PSAA distance.
CONCLUSION
CBCT-based estimates of CEJ-PSAA distance were comparable to those obtained in previous studies involving cadavers, CT, and CBCT. The type of CBCT scanner may slightly influence this measurement. No independent variable significantly impacted PSAA detection.
PubMed: 38948184
DOI: 10.5624/isd.20230160 -
ACS Omega Jun 2024This study aimed to investigate heterogeneous catalytic filaments of calcium oxide (CaO) for fused deposition modeling three-dimensional (3D) printers. The CaO catalysts...
This study aimed to investigate heterogeneous catalytic filaments of calcium oxide (CaO) for fused deposition modeling three-dimensional (3D) printers. The CaO catalysts were blended with acrylonitrile butadiene styrene (ABS) plastic to form catalytic filaments. A single-screw filament extruder was used to prepare the filaments, following which their mechanical properties, thermal properties, morphology, catalytic characteristics in biodiesel production, and reusability were evaluated. In accordance with the results, a maximum CaO catalyst content of 15 wt % was recommended to be blended in the ABS pellet. The hardness and compressive strength of these catalytic filaments were shown to be improved. Subsequently, the catalytic filaments with the highest CaO content (15 wt %) were used to produce methyl ester from pretreated sludge palm oil through the transesterification process. To determine the recommended conditions for achieving the highest purity of methyl ester in biodiesel, the process parameters were optimized. A methyl ester purity of 96.58 wt % and a biodiesel yield of 79.7 wt % could be achieved under the recommended conditions of a 9.0:1 methanol to oil molar ratio, 75.0 wt % catalytic filament loading, and 4.0 h reaction time. Furthermore, the reusability of the 15 wt % CaO catalytic filaments was evaluated in a batch process with multiple transesterification cycles. The results indicated that the purity of methyl ester dropped to 95.0 wt % only after the fourth cycle. The method used in this study for preparing and characterizing CaO catalytic filaments can potentially serve as a novel approach for constructing biodiesel reactors using 3D printing technology.
PubMed: 38947778
DOI: 10.1021/acsomega.4c03063 -
Cureus May 2024Dental anatomy exhibits considerable variation with the presence of additional canals being a common occurrence. The upper second molar typically presents with three...
Dental anatomy exhibits considerable variation with the presence of additional canals being a common occurrence. The upper second molar typically presents with three canals and three roots; however, variations such as the existence of an extra canal or a root can pose challenges during endodontic treatment. Maxillary molar is characterized by an additional canal located within the palatal root, often exhibiting complex configurations and variations in morphology. Access refinement is critical to gaining adequate visibility and facilitating instrumentation. Meticulous exploration of the pulp chamber floor and careful examination of radiographs from different angles are essential for accurate diagnosis. Careful negotiation and cleaning of the extra canal with appropriate files and irrigants are essential to remove pulp tissue and debris effectively. Furthermore, obturation of the canal space with biocompatible materials is crucial to ensure a three-dimensional seal and prevent bacterial ingress. Clinically, the inability to detect and treat the extra palatal canal can lead to persistent infection, incomplete debridement, and compromised treatment outcomes. This case report delves into the significance of this anatomical variation, diagnostic modalities, and effective management strategies.
PubMed: 38947704
DOI: 10.7759/cureus.61266 -
Cureus May 2024In this case report, we describe a 19-year-old man who underwent an autotransplantation of a lower third molar into the extracted region of his upper central incisors....
In this case report, we describe a 19-year-old man who underwent an autotransplantation of a lower third molar into the extracted region of his upper central incisors. Due to trauma, the patient's upper right and left central incisors had been extracted. He visited our clinic and requested to perform autotransplantation of his own teeth into the upper central incisor part because he wanted to use his natural teeth. So, we decided to extract his lower right third molar and autotransplant it into the extraction part of the upper central incisors. Immediately after extraction of the lower right third molar, the tooth was autotransplanted into the upper anterior region using a 3D-printed resin replica of the donor tooth and artificial sockets of the recipient site. Then, the root canal treatment was performed, and a temporary crown was set. Next, orthodontic treatment was done to flatten the curve of Spee. After completing the orthodontic treatment, a final prosthodontic restoration was set on the autotransplanted tooth. Four years later, the autotransplanted tooth remained stable with a healthy periodontium. This case demonstrates that if a patient has a request to use their natural teeth, autotransplantation of a wisdom tooth into the anterior region can be a useful method to replace the missing teeth.
PubMed: 38947626
DOI: 10.7759/cureus.61327 -
Cureus May 2024Odontogenic cervicofacial infections are still an ongoing problem, requiring immediate hospital admittance and management. The aim of this study is to reflect the...
INTRODUCTION
Odontogenic cervicofacial infections are still an ongoing problem, requiring immediate hospital admittance and management. The aim of this study is to reflect the number of patients with cervicofacial infections who were admitted during the coronavirus disease 2019 (COVID-19) pandemic period in a single, point of reference center in Northern Greece as well as analyze the quantitative and qualitative parameters of patient characteristics and management data.
METHODS
This was a retrospective cohort study that included all the patients with cervicofacial infections who were admitted to our unit during the COVID-19 pandemic, specifically between 2020 and 2021. For comparative reasons, patients admitted with cervicofacial infections between 2019 and 2020 (pre-COVID period) were analyzed.
RESULTS
In total, 341 patients fulfilled the criteria for this study. Specifically, the number of admitted patients was 151 in the pre-COVID era instead of 190 patients in the pandemic. The mean age of the patients was 45.3 years, with a slight male predominance (54.7% males to 45.3%). The mean duration of hospitalization was 2.5 days in the pre-COVID period instead of 3.42 days in the pandemic. Interestingly, in the pandemic, eight times more patients were admitted to the ICU post-operatively, in contrast to the pre-COVID period (23 vs 3 patients). Also in the COVID period, almost 54.9% of the patients presented with fever and 49.6% with trismus. Moreover, the submandibular space involvement was the most common space of infection in both COVID and pre-COVID groups with (58.9% and 49.7%) respectively. In one-third of all cases, a post-extraction infection of a third molar was the main cause of abscess.
CONCLUSION
Cervicofacial infections during the COVID-19 pandemic appeared with more severe symptoms and resulted in an increased number of patients who needed admittance to the intensive care unit, in contrast to the pre-COVID era. Also, the mean length of stay was increased for a day at the same period. This study could be used as an example for further research, in case of similar pandemic situations in the future.
PubMed: 38947612
DOI: 10.7759/cureus.61333 -
Cureus May 2024To analyze the effects of the maxillary second molar and third molar eruption stages on the distalization of first molars with a modified palatal anchorage plate (MPAP)...
Effect of Second and Third Molar Eruption Stages on First Molar and Maxillary Arch Distalization With Modified Palatal Anchorage Plate and Beneslider: A 3D Finite Element Analysis.
AIM
To analyze the effects of the maxillary second molar and third molar eruption stages on the distalization of first molars with a modified palatal anchorage plate (MPAP) and Beneslider using three-dimensional (3D) finite element analysis.
MATERIALS AND METHOD
Six finite element models (FEMs) of individual maxillary molar distalization and six FEM models of en-masse maxillary arch distalization (EMAD) at different stages of the maxillary molar eruption were created from cone-beam computed tomography (CBCT) images of the maxillary complex, and 3D displacements of the maxillary first and second molars were evaluated with MPAP and Beneslider.
RESULTS
On individual molar distalization, Beneslider showed first molar distal translation during the second and third molar follicular stages, while MPAP showed distal tipping of the first molar. With EMAD, either of the appliances showed distal tipping of the first molars. There was palatal rolling and extrusion of the first molars. The second molar showed buccal drifting with intrusion, and the incisors showed palatal displacement along with extrusion.
CONCLUSIONS
Second and third molar eruption stages had no adverse influence on first molar and en-masse maxillary arch distalization. Beneslider showed distal translation of the first molar, while distal tipping was seen with MPAP.
PubMed: 38947589
DOI: 10.7759/cureus.61403 -
Chemistry, An Asian Journal Jun 2024Photoinduced 3D printing via photocontrolled reversible-deactivation radical polymerization (photoRDRP) techniques has emerged as a robust technique for creating...
Photoinduced 3D printing via photocontrolled reversible-deactivation radical polymerization (photoRDRP) techniques has emerged as a robust technique for creating polymeric materials. However, methods for precisely adjusting the mechanical properties of these materials remain limited. In this study, we present a facile approach for adjusting the mechanical properties of 3D-printed objects by adjusting the polymer dispersity within a Norrish type I photoinitiated reversible addition-fragmentation chain transfer (NTI-RAFT) polymerization-based 3D printing process. We investigated the effects of varying the concentrations and molar ratios of trithiocarbonate (BTPA) and xanthate (EXEP) on the mechanical properties of the printed materials. Our findings demonstrate that increased concentrations of RAFT agents or higher proportions of the more active BTPA lead to a decrease in Young's modulus and glass transition temperatures, along with an increase in elongation at break, which can be attributed to the enhanced homogeneity of the polymer network. Using a commercial LCD printer, the NTI-RAFT-based 3D printing system effectively produced materials with tailored mechanical properties, highlighting its potential for practical applications.
PubMed: 38946109
DOI: 10.1002/asia.202400648 -
Journal of Oleo Science 2024The objectives were to optimize the reaction conditions for C10:0 incorporation into grapeseed (GS) oil, characterize the structured lipid (SL) product, and study the...
The objectives were to optimize the reaction conditions for C10:0 incorporation into grapeseed (GS) oil, characterize the structured lipid (SL) product, and study the changes in antioxidant activity of the SL. Taguchi method was used to optimize C10:0 incorporation by combining parameters in a total of 9 experiments. Lipozyme RM IM (Rhizomucor miehei immobilized lipase) and Lipozyme 435 (Candida antarctica recombinant immobilized lipase) were used as biocatalysts for the acidolysis reactions. C10:0 incorporation and triacylglycerol (TAG) species of the SL were analyzed to determine optimal conditions and enzyme type that gave higher incorporation. The optimal conditions were the same for both enzymes as follows: substrate molar ratio 1:3 (GS oil: C10:0), enzyme load 5% (w/w) of substrates, temperature 65℃, and time 12 h. HPLC analysis of SL gave MLM-type TAG species of 11.51±0.11 mol% and 12.68±0.34 mol% for Lipozyme RM IM and Lipozyme 435, respectively. GC analysis indicated that C10:0 incorporated at the sn-1,3 positions of the SL were 46.03±0.55 mol% and 47.28±1.22 mol%, respectively, for Lipozyme RM IM and Lipozyme 435. However, the total C10:0 incorporated into TAG species with Lipozyme RM IM was significantly higher (60.08±0.04 mol%) compared to 50.78±0.44 mol% for Lipozyme 435. Scaled-up (300 g) acidolysis reaction and characterization were done on SL synthesized using Lipozyme RM IM. SL reaction product was purified using short path distillation and fully characterized in terms of lipid classes, tocopherol, thermal behavior, and oxidative stability. The yield of purified scaled-up SL after short path distillation (SPD) was 72.96 wt%. The antioxidant in SL was reduced after SPD due to loss of tocopherols. This MLM-type-SL synthesized within 12 h using Lipozyme RM IM had a high content of C10:0 and may have functional and health benefits.
Topics: Lipase; Enzymes, Immobilized; Rhizomucor; Antioxidants; Decanoic Acids; Triglycerides; Plant Oils; Biocatalysis; Temperature; Time Factors; Basidiomycota
PubMed: 38945926
DOI: 10.5650/jos.ess23212 -
Dental Materials Journal Jun 2024Laboratory evidence has shown that 45S5 bioglass can help in dental remineralization, so its incorporation into resin-modified glass ionomer cement (RMGIC) has been...
Laboratory evidence has shown that 45S5 bioglass can help in dental remineralization, so its incorporation into resin-modified glass ionomer cement (RMGIC) has been studied. This randomized clinical trial aimed to determine the efficacy of RMGIC enriched with 10% 45S5 bioglass (RMGIC/45S5) in preventing the progression of moderate caries lesions. Sixty-six permanent molars with moderate caries lesions, were randomly sealed with RMGIC or RMGIC/45S5. After 1, 3-6 months, patients' oral health, material behavior, and caries evolution were evaluated. Chi-square and Fisher's exact test was employed. After one month, the RMGIC showed higher total retention and better clinical performance compared to RMGIC/45S5, both showed a predominance of sealed teeth or without caries progression. After 6 months, no materials retention, quality and caries progression difference was observed for both materials. Short-term clinical follow-up reveals worse retention and quality of RMGIC/45S5, only after 6 months no clinical/microscopic differences are observed between the materials.
PubMed: 38945864
DOI: 10.4012/dmj.2023-261 -
International Dental Journal Jun 2024The study aimed to investigate caries incidence and its associate factors among kindergarten children in Hong Kong.
OBJECTIVE
The study aimed to investigate caries incidence and its associate factors among kindergarten children in Hong Kong.
METHOD
This 30-month prospective study recruited 3- to 4-year-old children when they started their kindergarten study. A self-administered parental questionnaire survey was used to collect the children's social demographic information and their oral health-related habits. Child's caries experience was recorded using the decayed, missing, and filled tooth (dmft) index and the visible plaque index (VPI) was used to measure their oral hygiene status. A final examination was performed after 30 months when they were in the final year of kindergarten. Data were analysed using the zero-inflated negative binomial (ZINB) regression model.
RESULTS
This study examined 660 children at baseline and 501 children at the final examination (dropout 24%). At baseline, the caries prevalence among 501 children was 23%, with mean (SD) dmft scores of 0.7 (1.8). At the final examination, caries prevalence increased to 41%, with mean (SD) dmft scores of 1.6 (2.8). The 30-month incidence rate was 34%, and the mean (SD) number of new carious teeth developed was 0.9 (1.7). Lower first molars exhibited the highest caries increment rate (11%), followed by upper second molars (9%) and upper central incisors (9%). ZINB regression analysis revealed associations among caries incidence and family income, baseline dmft, and baseline VPI (P < .05).
CONCLUSIONS
One third of Hong Kong kindergarten children developed new caries. Low family income, prior caries experience and poor oral hygiene were the significant factors associated with their caries incidence.
CLINICAL RELEVANCE
Many children developed new caries during their kindergarten years, with their caries experience more than doubling. Preventive measures, including oral health education and reinforcing oral hygiene practice in kindergarten, are essential to reduce their caries incidence, particularly for children with low family income, caries experience and poor oral hygiene.
PubMed: 38945801
DOI: 10.1016/j.identj.2024.05.015