Ricinodendron heudelotii is a plant of the Euphorbiaceae family, used in traditional medicine to treat numerous diseases, including high blood pressure. The aim of this study is to evaluate the antioxidant and vasorelaxant effects of the aqueous extract of the stem bark of R. heudelotii. The pharmacological studies were carried out using the aqueous extract obtained by infusion. The antioxidant capacity of R. heudelotii was assessed by in vitro tests with DPPH (2,2-diphenyl-1-picryl-hydrazyl), ABTS (2,2'-azino-bis (3-ethylbenz-thiazoline-6-sulfonic acid), iron-reducing capacity (FRAP), and inhibition of nitric oxide (NO) release. In vitro studies, the aortic rings obtained from adult Wistar albino rats of both sexes were used to determine the vasorelaxant effects of the extract of R. heudelotii on the NO and prostacyclin (PGI2) pathways as well as its involvement on various potassium channels were determined on intact or naked fragments of rat aorta precontracted with phenylephrine (10-6 M) or KCl (60 mM). The aqueous extract of R. heudelotii exhibited a remarkable DPPH (EC50: 1.68 μg/mL) and ABTS (EC50: 106.30 μg/mL) and nitric oxide (53.71% inhibition at 1000 μg/mL) radical scavenging activities as well as reducing power (absorbance of 1.56 at 1000 μg/mL). The nitric oxide inhibitor, NG-nitro-L-arginine methyl ester (L-NAME), and prostacyclin inhibitor, indomethacin, significantly attenuated the vasodilatory effect of R. heudelotii. Tetraethylammonium could not inhibit the vasodilatory effect of the extract, unlike glibenclamide and barium chloride. Ricinodendron heudelotii extract possesses antioxidant properties and vasorelaxing effect linked to endothelium-related factors, and this relaxation was partially mediated mainly through the inhibition of Kir and KATP channels.
Ricinodendron heudelotii 是一种大戟科植物,在传统医学中用于治疗包括高血压在内的多种疾病。本研究旨在评估 R. heudelotii 茎皮水提取物的抗氧化和舒张血管作用。药理研究使用的是通过浸泡获得的水提取物。通过 DPPH(2,2-二苯基-1-苦基肼)、ABTS(2,2'-偶氮-双(3-乙基苯并噻唑啉-6-磺酸))、铁还原能力(FRAP)和抑制一氧化氮(NO)释放的体外测试,评估了 R. heudelotii 的抗氧化能力。体外研究采用成年 Wistar 白化大鼠(雌雄均可)的主动脉环,测定 R. heudelotii 提取物对一氧化氮和前列环素(PGI2)途径的血管舒张作用,以及在用苯肾上腺素(10-6 M)或氯化钾(60 mM)预收缩的完整或裸露大鼠主动脉片段上对各种钾通道的参与作用。R. heudelotii 的水提取物具有显著的 DPPH(EC50:1.68 μg/mL)、ABTS(EC50:106.30 μg/mL)和一氧化氮(1000 μg/mL时抑制率为 53.71%)自由基清除活性以及还原力(1000 μg/mL时吸光度为 1.56)。一氧化氮抑制剂 NG-硝基-L-精氨酸甲酯(L-NAME)和前列环素抑制剂吲哚美辛能明显减弱 R. heudelotii 的血管扩张作用。与格列本脲和氯化钡不同,四乙基铵不能抑制提取物的血管扩张作用。柘树提取物具有抗氧化特性和血管舒张作用,这与内皮相关因子有关,而这种舒张作用部分主要是通过抑制Kir和KATP通道介导的。
{"title":"Antioxidant Properties and Vasorelaxant Mechanism of Aqueous Extract <i>of Ricinodendron heudelotii</i> (Euphorbiaceae).","authors":"Jacquy Joyce Wanche Kojom, Calvin Zangueu Bogning, Edwige Laure Lappa, Christelle Stéphanie Sonfack, Augustine Nkojap Kuinze, Gisèle Etamé-Loé, Alain Bertrand Dongmo","doi":"10.1155/2024/3435974","DOIUrl":"10.1155/2024/3435974","url":null,"abstract":"<p><p><i>Ricinodendron heudelotii</i> is a plant of the Euphorbiaceae family, used in traditional medicine to treat numerous diseases, including high blood pressure. The aim of this study is to evaluate the antioxidant and vasorelaxant effects of the aqueous extract of the stem bark of <i>R. heudelotii</i>. The pharmacological studies were carried out using the aqueous extract obtained by infusion. The antioxidant capacity of <i>R. heudelotii</i> was assessed by in vitro tests with DPPH (2,2-diphenyl-1-picryl-hydrazyl), ABTS (2,2'-azino-bis (3-ethylbenz-thiazoline-6-sulfonic acid), iron-reducing capacity (FRAP), and inhibition of nitric oxide (NO) release. In vitro studies, the aortic rings obtained from adult Wistar albino rats of both sexes were used to determine the vasorelaxant effects of the extract of <i>R. heudelotii</i> on the NO and prostacyclin (PGI2) pathways as well as its involvement on various potassium channels were determined on intact or naked fragments of rat aorta precontracted with phenylephrine (10<sup>-6</sup> M) or KCl (60 mM). The aqueous extract of <i>R. heudelotii</i> exhibited a remarkable DPPH (EC<sub>50</sub>: 1.68 <i>μ</i>g/mL) and ABTS (EC<sub>50</sub>: 106.30 <i>μ</i>g/mL) and nitric oxide (53.71% inhibition at 1000 <i>μ</i>g/mL) radical scavenging activities as well as reducing power (absorbance of 1.56 at 1000 <i>μ</i>g/mL). The nitric oxide inhibitor, N<sub>G</sub>-nitro-L-arginine methyl ester (L-NAME), and prostacyclin inhibitor, indomethacin, significantly attenuated the vasodilatory effect of <i>R. heudelotii</i>. Tetraethylammonium could not inhibit the vasodilatory effect of the extract, unlike glibenclamide and barium chloride. <i>Ricinodendron heudelotii</i> extract possesses antioxidant properties and vasorelaxing effect linked to endothelium-related factors, and this relaxation was partially mediated mainly through the inhibition of K<sub>ir</sub> and K<sub>ATP</sub> channels.</p>","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11419840/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142307092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: Paracetamol, also known as acetaminophen, is categorized as an analgesic and antipyretic medication and is available as over the counter (OTC) medication. It is commonly used in conditions associated with pain and fever. There is a tendency for community to prefer using imported paracetamol tablets from Europe and United States than from Asia and Africa worrying of the quality of the products. Safety, effectiveness, and efficacy of a medicine can be guaranteed when its quality is reliable; however, there is limited data on the quality of locally manufactured paracetamol tablets, thus necessitating this study. Aim: This study is aimed at assessing the quality of paracetamol tablets 500 mg manufactured by local companies by evaluating their physical parameters, assay results, and dissolution profiles. The compliance of these tablets with the specifications outlined in the British Pharmacopoeia (BP) was analyzed. Additionally, a comparative dissolution test was conducted to assess dissolution profile for innovator product and generics. Method: Five different brands from East African countries with 76 tablets from each brand were compared with the innovator product regarding weight variation, hardness, friability, assay, and dissolution test based on the BP specifications. Results and discussion: All samples of paracetamol tablets 500 mg from the local manufacturers in this study met the specifications set by the BP for physical parameters, including weight variation, friability, hardness, and disintegration tests. The weight variation test, directly related to drug content variation, demonstrated compliance within the acceptable deviation of 5%. Similarly, the assay test, which determines the concentration of the active pharmaceutical ingredient (API), confirmed that all samples complied with the acceptable concentration range of 90%-110% for paracetamol. The dissolution test, assessing the percentage release of the API within a specified time, demonstrated that at 15 min, two samples (diodol and enamol) exhibited lower concentration releases than the required 80%, indicating potential delays in their bioavailability and onset of action. Conclusion: To conclude, all samples had good quality and they can be used for their therapeutic purposes.
{"title":"Quality Evaluation of Locally Manufactured Paracetamol Tablets in East Africa.","authors":"Gerald Marisa, James Kapala, Tanga Mafuru, Raphael Matinde, Emmanuel Kimaro, Eliangiringa Kaale","doi":"10.1155/2024/9437835","DOIUrl":"10.1155/2024/9437835","url":null,"abstract":"<p><p><b>Background:</b> Paracetamol, also known as acetaminophen, is categorized as an analgesic and antipyretic medication and is available as over the counter (OTC) medication. It is commonly used in conditions associated with pain and fever. There is a tendency for community to prefer using imported paracetamol tablets from Europe and United States than from Asia and Africa worrying of the quality of the products. Safety, effectiveness, and efficacy of a medicine can be guaranteed when its quality is reliable; however, there is limited data on the quality of locally manufactured paracetamol tablets, thus necessitating this study. <b>Aim:</b> This study is aimed at assessing the quality of paracetamol tablets 500 mg manufactured by local companies by evaluating their physical parameters, assay results, and dissolution profiles. The compliance of these tablets with the specifications outlined in the British Pharmacopoeia (BP) was analyzed. Additionally, a comparative dissolution test was conducted to assess dissolution profile for innovator product and generics. <b>Method:</b> Five different brands from East African countries with 76 tablets from each brand were compared with the innovator product regarding weight variation, hardness, friability, assay, and dissolution test based on the BP specifications. <b>Results and discussion:</b> All samples of paracetamol tablets 500 mg from the local manufacturers in this study met the specifications set by the BP for physical parameters, including weight variation, friability, hardness, and disintegration tests. The weight variation test, directly related to drug content variation, demonstrated compliance within the acceptable deviation of 5%. Similarly, the assay test, which determines the concentration of the active pharmaceutical ingredient (API), confirmed that all samples complied with the acceptable concentration range of 90%-110% for paracetamol. The dissolution test, assessing the percentage release of the API within a specified time, demonstrated that at 15 min, two samples (diodol and enamol) exhibited lower concentration releases than the required 80%, indicating potential delays in their bioavailability and onset of action. <b>Conclusion:</b> To conclude, all samples had good quality and they can be used for their therapeutic purposes.</p>","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11416170/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142280151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Romial Joel Ngouénam,Ghadir Nofal,Sanjukta Patra,Bilkissou Njapndounke,Edith Marius Foko Kouam,Pierre Marie Kaktcham,François Zambou Ngoufack
This study investigated the ability of lactic acid bacteria (LAB) isolated from oranges to use fish by-products (FB) and chicken by-products (CB) as nitrogen sources alternative to yeast extract for lactic acid (LA) production in a papaya by-product medium as a carbon source. Once the fermentation agents had been isolated, they were subjected to biochemical and molecular characterization. Inexpensive nitrogen sources, precisely CB and FB, were prepared, freeze-dried, and yield evaluated. Also, before to the fermentation experiments, the Total Kjehdahl Nitrogen (TKN) of these by-products and that of the yeast extract were determined. Then, three production media differing in terms of nitrogen source were formulated from these nitrogen sources. From the 22 LAB isolated from orange, two isolates of interest (NGO25 and NGO23) were obtained; all belonging to the Lactiplantibacillus plantarum species based on 16S rRNA gene sequencing. Furthermore, the production yield powder obtained after lyophilization of 1 L of CB and FB surpernatant were, respectively, 16.6 g and 12.933 g. The TKN of different nitrogen sources powder were 71.4 ± 0.000% DM (FB), 86.145 ± 0.001% DM (CB), and 87.5 ± 0.99% DM (yeast extract). The best kinetic parameters of LA production (LA (g/L): 31.945 ± 0.078; volumetric productivity (g/L.h): 1.331 ± 0.003; LA yield (mg/g) 63.89 ± 0.156; biomass (g/L) 7.925 ± 0.035; cell growth rate (g/L.h): 0.330 ± 0.001) were recorded by Lactiplantibacillus plantarum NGO25 after 24 h of fermentation. The latter data were obtained in the production medium containing CB as nitrogen sources. In addition, this production medium cost only $0.152 to formulate, compared to yeast extract which required $1.692 to formulate. Thus, freeze-dried CB can be used as an alternative to yeast extract in large-scale production of LA.
{"title":"Characterization of Lactic Acid Bacteria Isolated From Rotting Oranges and Use of Agropastoral Processing By-products as Carbon and Nitrogen Sources Alternative for Lactic Acid Production.","authors":"Romial Joel Ngouénam,Ghadir Nofal,Sanjukta Patra,Bilkissou Njapndounke,Edith Marius Foko Kouam,Pierre Marie Kaktcham,François Zambou Ngoufack","doi":"10.1155/2024/4264229","DOIUrl":"https://doi.org/10.1155/2024/4264229","url":null,"abstract":"This study investigated the ability of lactic acid bacteria (LAB) isolated from oranges to use fish by-products (FB) and chicken by-products (CB) as nitrogen sources alternative to yeast extract for lactic acid (LA) production in a papaya by-product medium as a carbon source. Once the fermentation agents had been isolated, they were subjected to biochemical and molecular characterization. Inexpensive nitrogen sources, precisely CB and FB, were prepared, freeze-dried, and yield evaluated. Also, before to the fermentation experiments, the Total Kjehdahl Nitrogen (TKN) of these by-products and that of the yeast extract were determined. Then, three production media differing in terms of nitrogen source were formulated from these nitrogen sources. From the 22 LAB isolated from orange, two isolates of interest (NGO25 and NGO23) were obtained; all belonging to the Lactiplantibacillus plantarum species based on 16S rRNA gene sequencing. Furthermore, the production yield powder obtained after lyophilization of 1 L of CB and FB surpernatant were, respectively, 16.6 g and 12.933 g. The TKN of different nitrogen sources powder were 71.4 ± 0.000% DM (FB), 86.145 ± 0.001% DM (CB), and 87.5 ± 0.99% DM (yeast extract). The best kinetic parameters of LA production (LA (g/L): 31.945 ± 0.078; volumetric productivity (g/L.h): 1.331 ± 0.003; LA yield (mg/g) 63.89 ± 0.156; biomass (g/L) 7.925 ± 0.035; cell growth rate (g/L.h): 0.330 ± 0.001) were recorded by Lactiplantibacillus plantarum NGO25 after 24 h of fermentation. The latter data were obtained in the production medium containing CB as nitrogen sources. In addition, this production medium cost only $0.152 to formulate, compared to yeast extract which required $1.692 to formulate. Thus, freeze-dried CB can be used as an alternative to yeast extract in large-scale production of LA.","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142254412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Study Objective: The present study is aimed at providing an assessment of the changes in burnout, job strain, isostrain, sleepiness, and fatigue levels over time and identifying factors associated with these symptoms among healthcare workers in French emergency departments (EDs). Method: We conducted a prospective, multicenter study in four EDs and an emergency medical service. Participants completed questionnaires at inclusion and at 90 days to assess burnout, job strain, isostrain, sleepiness, and fatigue. Results: A total of 211 respondents (43.5%) completed the questionnaires at inclusion. At the beginning of the study, 84 (40.8%) participants presented symptoms of burnout, 86 (43.2%) had symptoms of job strain, and 58 (29.4%) of isostrain. Forty-two (20.1%) healthcare workers presented symptoms of sleepiness, and 8 (3.8%) had symptoms of fatigue. We found that symptoms of burnout were more frequent for healthcare workers with a previous psychiatric history (55.3% vs. 39.1%, p = 0.02) and were lower among participants who had at least one dependent child (33.1% vs. 48.3%, p = 0.013). Symptoms of job strain were higher among administrative staff compared to physicians (55.6% vs. 28.7%, p = 0.01) and among healthcare workers with managerial responsibilities compared to those without (45.6% vs. 28.8%, p = 0.015). Symptoms of isostrain were higher among administrative staff (42.3%) compared to paramedics (34.1%) and physicians (19.8%, p = 0.026). Conclusion: We identified that potential factors associated with the emergence of symptoms of burnout and job strain are suggested, underlining several areas of improvement for the prevention against mental health disorders in the specific population of ED healthcare workers. Trial Registration: ClinicalTrials.gov identifier: NCT04383886.
{"title":"Mental Health Consequences of the COVID-19 Outbreak Among Emergency Department Healthcare Workers.","authors":"Marion Douplat,Fabien Subtil,Anne Termoz,Laurent Jacquin,Frédéric Verbois,Veronique Potinet,Romain Hernu,Verena Landel,Stéphanie Mazza,Julien Berthiller,Julie Haesebaert,Karim Tazarourte","doi":"10.1155/2024/8871959","DOIUrl":"https://doi.org/10.1155/2024/8871959","url":null,"abstract":"Study Objective: The present study is aimed at providing an assessment of the changes in burnout, job strain, isostrain, sleepiness, and fatigue levels over time and identifying factors associated with these symptoms among healthcare workers in French emergency departments (EDs). Method: We conducted a prospective, multicenter study in four EDs and an emergency medical service. Participants completed questionnaires at inclusion and at 90 days to assess burnout, job strain, isostrain, sleepiness, and fatigue. Results: A total of 211 respondents (43.5%) completed the questionnaires at inclusion. At the beginning of the study, 84 (40.8%) participants presented symptoms of burnout, 86 (43.2%) had symptoms of job strain, and 58 (29.4%) of isostrain. Forty-two (20.1%) healthcare workers presented symptoms of sleepiness, and 8 (3.8%) had symptoms of fatigue. We found that symptoms of burnout were more frequent for healthcare workers with a previous psychiatric history (55.3% vs. 39.1%, p = 0.02) and were lower among participants who had at least one dependent child (33.1% vs. 48.3%, p = 0.013). Symptoms of job strain were higher among administrative staff compared to physicians (55.6% vs. 28.7%, p = 0.01) and among healthcare workers with managerial responsibilities compared to those without (45.6% vs. 28.8%, p = 0.015). Symptoms of isostrain were higher among administrative staff (42.3%) compared to paramedics (34.1%) and physicians (19.8%, p = 0.026). Conclusion: We identified that potential factors associated with the emergence of symptoms of burnout and job strain are suggested, underlining several areas of improvement for the prevention against mental health disorders in the specific population of ED healthcare workers. Trial Registration: ClinicalTrials.gov identifier: NCT04383886.","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142254413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Giovanni Damiani,Laura Cristina Gironi,Rosalynn R Z Conic,Massimo Del Fabbro,Paola Savoia,Marco Fiore,Wilma F Bergfeld
Background: The potential link between alopecia areata (AA) and eosinophilia is unclear, as well as its clinical manifestations in these patients' subsets. Methods: This is a monocentric retrospective observational study in which clinical and laboratory data were summarized and evaluated the AA subset with concurrent eosinophilia. Results: In a sample of 205 AA patients, 38 (18.5%) were classified as AA with eosinophilia. Interestingly, this subset of patients had a statistically higher prevalence of atopia and nail abnormalities (p < 0.05) than AA without eosinophilia. AA patients with eosinophilia had a 3.70 higher odds of more severe hair loss versus age- and gender-matched AA without eosinophilia. Conclusions: AA patients with eosinophilia had distinctive clinical and laboratory characteristics, so future studies may potentially explore the use of IL-5 inhibitors.
背景:斑秃(AA)与嗜酸性粒细胞增多症之间的潜在联系及其在这些患者亚群中的临床表现尚不清楚。研究方法这是一项单中心回顾性观察研究,对临床和实验室数据进行了总结,并对同时患有嗜酸性粒细胞增多症的 AA 亚组进行了评估。研究结果在 205 例 AA 患者中,有 38 例(18.5%)被归类为嗜酸性粒细胞增多的 AA 患者。有趣的是,与无嗜酸性粒细胞增多症的 AA 患者相比,该组患者的近视率和指甲异常率在统计学上更高(P < 0.05)。与无嗜酸性粒细胞增多症的年龄和性别匹配的 AA 患者相比,有嗜酸性粒细胞增多症的 AA 患者出现更严重脱发的几率要高出 3.70 倍。结论:嗜酸性粒细胞增多症 AA 患者具有独特的临床和实验室特征,因此未来的研究可能会探讨 IL-5 抑制剂的使用。
{"title":"Concurrent Eosinophilia Increases the Prevalence of Nail Abnormalities and Severity of Hair Loss in Patients With Alopecia Areata.","authors":"Giovanni Damiani,Laura Cristina Gironi,Rosalynn R Z Conic,Massimo Del Fabbro,Paola Savoia,Marco Fiore,Wilma F Bergfeld","doi":"10.1155/2024/5596647","DOIUrl":"https://doi.org/10.1155/2024/5596647","url":null,"abstract":"Background: The potential link between alopecia areata (AA) and eosinophilia is unclear, as well as its clinical manifestations in these patients' subsets. Methods: This is a monocentric retrospective observational study in which clinical and laboratory data were summarized and evaluated the AA subset with concurrent eosinophilia. Results: In a sample of 205 AA patients, 38 (18.5%) were classified as AA with eosinophilia. Interestingly, this subset of patients had a statistically higher prevalence of atopia and nail abnormalities (p < 0.05) than AA without eosinophilia. AA patients with eosinophilia had a 3.70 higher odds of more severe hair loss versus age- and gender-matched AA without eosinophilia. Conclusions: AA patients with eosinophilia had distinctive clinical and laboratory characteristics, so future studies may potentially explore the use of IL-5 inhibitors.","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142254414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joyce R C Dos S Siqueira,Rita M M Rodriguez,Nathalia de C Ramos,Marco A Bottino,João P M Tribst
Background: Over the past decade, 3D printing technology has revolutionized various fields, including dentistry. Provisional restorations play a crucial role in prosthetic rehabilitation, necessitating the evaluation of their bond strength with different provisional cement agents. Aims: This study is aimed at assessing the immediate and long-term bond strength of 3D-printed dental crowns using three provisional cement agents. Materials and Methods: Provisional crowns (N = 36) were manufactured using 3D modeling software and cemented in dentin analogues (G10 Nema resin). After the crowns' fabrication, they were randomly divided into three groups (n = 12) for cementation with Relyx Temp 3M ESPE, Provicol-VOCO, and Meron-VOCO. Tensile strength tests were conducted using a universal testing machine, with half of the specimens subjected to 2000 thermal cycles before testing. Finite element analysis was employed to assess tensile stress distribution. Results: Statistical analysis (two-way ANOVA and Tukey's test at a 95% confidence level) revealed significant effects of cement type (p = 0.006) and thermal aging (p = 0.001) on bond strength. Glass ionomer cement exhibited the highest immediate resistance, while all types of cement were adversely affected by thermal aging, resulting in decreased bond strength. Conclusion: Thermal aging significantly alters the properties of 3D printing resin and affects the bond strength of provisional cement with 3D-printed crowns. Despite the adverse effects of thermal aging, glass ionomer cement demonstrated the highest immediate resistance. Clinicians should carefully consider these findings when selecting provisional cements for 3D-printed crowns.
背景:在过去的十年中,3D 打印技术给包括牙科在内的各个领域带来了革命性的变化。临时修复体在修复过程中起着至关重要的作用,因此有必要对其与不同临时粘接剂的粘接强度进行评估。目的:本研究旨在评估使用三种临时粘接剂的 3D 打印牙冠的即刻和长期粘接强度。材料和方法:使用三维建模软件制作临时牙冠(N = 36),并与牙本质类似物(G10 Nema 树脂)粘接。牙冠制作完成后,随机分为三组(n = 12),分别使用 Relyx Temp 3M ESPE、Provicol-VOCO 和 Meron-VOCO进行粘接。使用万能试验机进行拉伸强度测试,其中一半试样在测试前进行了 2000 次热循环。采用有限元分析评估拉伸应力分布。结果统计分析(95% 置信度下的双向方差分析和 Tukey 检验)显示,水泥类型(p = 0.006)和热老化(p = 0.001)对粘接强度有显著影响。玻璃离子聚合物水门汀表现出最高的即刻耐受性,而所有类型的水门汀都受到热老化的不利影响,导致粘结强度下降。结论:热老化会明显改变 3D 打印树脂的特性,并影响临时粘接剂与 3D 打印牙冠的粘接强度。尽管热老化会产生不利影响,但玻璃离子聚合物水泥的即刻耐受性最高。临床医生在为 3D 打印牙冠选择临时粘接剂时应仔细考虑这些发现。
{"title":"Immediate and Long-Term Pull-Out Bond Strength of 3D-Printed Provisional Crowns.","authors":"Joyce R C Dos S Siqueira,Rita M M Rodriguez,Nathalia de C Ramos,Marco A Bottino,João P M Tribst","doi":"10.1155/2024/7205011","DOIUrl":"https://doi.org/10.1155/2024/7205011","url":null,"abstract":"Background: Over the past decade, 3D printing technology has revolutionized various fields, including dentistry. Provisional restorations play a crucial role in prosthetic rehabilitation, necessitating the evaluation of their bond strength with different provisional cement agents. Aims: This study is aimed at assessing the immediate and long-term bond strength of 3D-printed dental crowns using three provisional cement agents. Materials and Methods: Provisional crowns (N = 36) were manufactured using 3D modeling software and cemented in dentin analogues (G10 Nema resin). After the crowns' fabrication, they were randomly divided into three groups (n = 12) for cementation with Relyx Temp 3M ESPE, Provicol-VOCO, and Meron-VOCO. Tensile strength tests were conducted using a universal testing machine, with half of the specimens subjected to 2000 thermal cycles before testing. Finite element analysis was employed to assess tensile stress distribution. Results: Statistical analysis (two-way ANOVA and Tukey's test at a 95% confidence level) revealed significant effects of cement type (p = 0.006) and thermal aging (p = 0.001) on bond strength. Glass ionomer cement exhibited the highest immediate resistance, while all types of cement were adversely affected by thermal aging, resulting in decreased bond strength. Conclusion: Thermal aging significantly alters the properties of 3D printing resin and affects the bond strength of provisional cement with 3D-printed crowns. Despite the adverse effects of thermal aging, glass ionomer cement demonstrated the highest immediate resistance. Clinicians should carefully consider these findings when selecting provisional cements for 3D-printed crowns.","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: The precision of postoperative prostate cancer radiotherapy is significantly influenced by setup errors and alterations in bladder morphology. Utilizing daily cone beam computed tomography (CBCT) imaging allows for the correction of setup errors. However, this naturally leads to the question of the issue of peripheral dose and workload. Thus, a zero-dose, noninvasive technique to reproduce the bladder volume and improve patient setup accuracy was needed. Purpose: The aim of this study is to investigate if the setup method by combining Optical Surface Management System (OSMS) and BladderScan can improve the accuracy of setup and accurately reproduce the bladder volume during radiotherapy of postoperative prostate cancer and to guide CTV-PTV margins for clinic. Method: The experimental group consisted of 15 postoperative prostate cancer patients who utilized a setup method that combined OSMS and BladderScan. This group recorded 103 setup errors, verified by CBCT. The control group comprised 25 patients, among whom 114 setup errors were recorded using the conventional setup method involving skin markers; additionally, patients in this group also exhibited spontaneous urinary suppression. The errors including lateral (Lat), longitudinal (Lng), vertical directions (Vrt), Pitch, Yaw, and Roll were analyzed between the two methods. The Dice similarity coefficient (DSC) and volume differences of the bladder between CBCT and planning CT were compared as the bladder concordance indicators. Results: The errors in the experimental group at Vrt, Lat, and Lng were 0.17 ± 0.12, 0.22 ± 0.17, and 0.18 ± 0.12 cm, and the control group were 0.25 ± 0.15, 0.31 ± 0.21, 0.34 ± 0.22 cm. The rotation errors of Pitch, Roll, and Yaw in the experimental group were 0.18 ± 0.12°, 0.11 ± 0.1°, and 0.18 ± 0.13°, and in the control group, they were 0.96 ± 0.89°, 1.01 ± 0.86°, and 1.02 ± 0.84°. The DSC and volume differences were 92.52 ± 1.65% and 39.99 ± 28.75 cm3 in the patients with BladderScan, and in the control group, they were 62.98 ± 22.33%, 273.89 ± 190.62 cm3. The P < 0.01 of the above performance indicators indicates that the difference is statistically significant. Conclusion: The accuracy of the setup method by combining OSMS and BladderScan was validated by CBCT in our study. The method in our study can improve the setup accuracy during radiotherapy of postoperative prostate cancer compared to the conventional setup method.
{"title":"Optical Surface Management System and BladderScan for Patient Setup During Radiotherapy of Postoperative Prostate Cancer.","authors":"Hao Chen,Yandong Liu,Songbin Qin,Guanghui Gan","doi":"10.1155/2024/3573796","DOIUrl":"https://doi.org/10.1155/2024/3573796","url":null,"abstract":"Background: The precision of postoperative prostate cancer radiotherapy is significantly influenced by setup errors and alterations in bladder morphology. Utilizing daily cone beam computed tomography (CBCT) imaging allows for the correction of setup errors. However, this naturally leads to the question of the issue of peripheral dose and workload. Thus, a zero-dose, noninvasive technique to reproduce the bladder volume and improve patient setup accuracy was needed. Purpose: The aim of this study is to investigate if the setup method by combining Optical Surface Management System (OSMS) and BladderScan can improve the accuracy of setup and accurately reproduce the bladder volume during radiotherapy of postoperative prostate cancer and to guide CTV-PTV margins for clinic. Method: The experimental group consisted of 15 postoperative prostate cancer patients who utilized a setup method that combined OSMS and BladderScan. This group recorded 103 setup errors, verified by CBCT. The control group comprised 25 patients, among whom 114 setup errors were recorded using the conventional setup method involving skin markers; additionally, patients in this group also exhibited spontaneous urinary suppression. The errors including lateral (Lat), longitudinal (Lng), vertical directions (Vrt), Pitch, Yaw, and Roll were analyzed between the two methods. The Dice similarity coefficient (DSC) and volume differences of the bladder between CBCT and planning CT were compared as the bladder concordance indicators. Results: The errors in the experimental group at Vrt, Lat, and Lng were 0.17 ± 0.12, 0.22 ± 0.17, and 0.18 ± 0.12 cm, and the control group were 0.25 ± 0.15, 0.31 ± 0.21, 0.34 ± 0.22 cm. The rotation errors of Pitch, Roll, and Yaw in the experimental group were 0.18 ± 0.12°, 0.11 ± 0.1°, and 0.18 ± 0.13°, and in the control group, they were 0.96 ± 0.89°, 1.01 ± 0.86°, and 1.02 ± 0.84°. The DSC and volume differences were 92.52 ± 1.65% and 39.99 ± 28.75 cm3 in the patients with BladderScan, and in the control group, they were 62.98 ± 22.33%, 273.89 ± 190.62 cm3. The P < 0.01 of the above performance indicators indicates that the difference is statistically significant. Conclusion: The accuracy of the setup method by combining OSMS and BladderScan was validated by CBCT in our study. The method in our study can improve the setup accuracy during radiotherapy of postoperative prostate cancer compared to the conventional setup method.","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-02eCollection Date: 2024-01-01DOI: 10.1155/2024/1833140
Bashiru Babatunde Jimah, Benjamin Dabo Sarkodie, Asare Kwaku Offei, Ewurama Andam Idun, Dorothea Anim, Edmund Brakohiapa, Benard Ohene Botwe
Objectives: The radiographic assessment of the head is a crucial part of headache care. A computed tomography (CT) scan enables a more detailed analysis of the condition and more focused care. This study examined head CT scans to determine what kinds of anomalies were present in patients with headaches as their primary complaint. Methods: We evaluated 4 years' worth of CT scan data from head exams conducted at two diagnostic facilities in Ghana's western and central regions. We examined data on 477 patients with a headache as their primary complaint between January 2017 and December 2020. We employed chi-square and Fisher's exact tests (where applicable) to compare head CT diagnoses between age groups, gender, headache subtypes, and brain lesion subgroups. Results: There were 53.5% (n = 255) females and 46.5% (n = 222) males in the study. The average age of patients was 38.67 ± 17.23 years, with an annual rate of abnormal CT diagnoses ranging from 35.9% in 2017 to 45.4% in 2022. Abnormal head CT diagnoses are strongly correlated with age groups and patient gender (p = 0.011 and p = 0.009, respectively). Of the 202 patients, 15.3% and 24.3% were classified as intracranial lesions and extracranial lesions, respectively. Maxillary sinusitis affected nearly 60% of the patients, while tumors and hemorrhages affected 25.2% and 11.9%, respectively. Conclusions: A CT scan of the head is essential to detect abnormalities in nearly 50% of patients suffering from various degrees of headache. Sinusitis, brain tumors, and hemorrhage were common lesions detected. It is crucial to create local standard operating procedures to promote better utilization of this type of imaging service, particularly among patients who have been diagnosed with headaches.
{"title":"Computed Tomography Findings of Patients Presenting With Headache: 4-Year Retrospective Two-Center Study in Central and Western Regions of Ghana.","authors":"Bashiru Babatunde Jimah, Benjamin Dabo Sarkodie, Asare Kwaku Offei, Ewurama Andam Idun, Dorothea Anim, Edmund Brakohiapa, Benard Ohene Botwe","doi":"10.1155/2024/1833140","DOIUrl":"10.1155/2024/1833140","url":null,"abstract":"<p><p><b>Objectives:</b> The radiographic assessment of the head is a crucial part of headache care. A computed tomography (CT) scan enables a more detailed analysis of the condition and more focused care. This study examined head CT scans to determine what kinds of anomalies were present in patients with headaches as their primary complaint. <b>Methods:</b> We evaluated 4 years' worth of CT scan data from head exams conducted at two diagnostic facilities in Ghana's western and central regions. We examined data on 477 patients with a headache as their primary complaint between January 2017 and December 2020. We employed chi-square and Fisher's exact tests (where applicable) to compare head CT diagnoses between age groups, gender, headache subtypes, and brain lesion subgroups. <b>Results:</b> There were 53.5% (<i>n</i> = 255) females and 46.5% (<i>n</i> = 222) males in the study. The average age of patients was 38.67 ± 17.23 years, with an annual rate of abnormal CT diagnoses ranging from 35.9% in 2017 to 45.4% in 2022. Abnormal head CT diagnoses are strongly correlated with age groups and patient gender (<i>p</i> = 0.011 and <i>p</i> = 0.009, respectively). Of the 202 patients, 15.3% and 24.3% were classified as intracranial lesions and extracranial lesions, respectively. Maxillary sinusitis affected nearly 60% of the patients, while tumors and hemorrhages affected 25.2% and 11.9%, respectively. <b>Conclusions:</b> A CT scan of the head is essential to detect abnormalities in nearly 50% of patients suffering from various degrees of headache. Sinusitis, brain tumors, and hemorrhage were common lesions detected. It is crucial to create local standard operating procedures to promote better utilization of this type of imaging service, particularly among patients who have been diagnosed with headaches.</p>","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11383647/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142280150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-30eCollection Date: 2024-01-01DOI: 10.1155/2024/1906797
Courage Edem Ketor, Charles Kwaku Benneh, Emmanuel Sarkodie, Juliet Ama Anaglo, Adelaide Mensah, Samuel Owusu Somuah, Selorm Akakpo, Eric Woode
Background: Analysing data on adverse drug reactions (ADRs) in health facilities is an essential step to help develop effective strategies to reduce their incidence. The objective was to analyse spontaneous ADR reports sent to the Ghanaian Food and Drugs Authority (FDA) by two reporting health facilities over 5 years. Methods: Data from duplicate spontaneous ADR reports sent to the FDA (Ghana) from 2014 to 2018 were extracted. The relationship between independent variables such as age, sex, and source of drugs and ADR outcomes was assessed with either chi-square or a Cramer's V test for association where appropriate. Results: Type A reactions (65.2%) were the most prevalent of the ADRs, followed by Type B (34.1%), with the majority (80%) of patients affected recovering fully. The majority of Type A reactions (54.1%) occurred in the clinic, while the majority of Type B reactions (43.5%) occurred in the hospital. The skin and central nervous system (CNS) were the most affected (70.8%) organs. A higher incidence of CNS and skin-related ADRs was recorded in patients older than 30 (RR = 1.28 (1.07-1.53)). Also, females were more likely to experience a CNS-related ADR. The seriousness of the ADR was found to be significantly associated with the (1) type of prescriber, (2) whether the drug was prescribed, or (3) whether the drug regimen prescribed was appropriate. Even though, in 86% of cases, the offending drug was withdrawn within the first 5 days, it exceeded 20 days in about 6% of cases. The record of allergy status in a patient's folder and the source of the drug were significantly associated with the chance that the offending drug was withdrawn. However, recording ADRs did not influence whether the offending drug was stopped. Conclusion: Most of the ADRs experienced by patients could be avoided if the current systems are improved to prevent the rechallenge of offending drugs. Efforts to improve and update patient medication records and steps to ensure continuity of care are essential in preventing these adverse drug events.
{"title":"Analysis of Spontaneously Reported Adverse Drug Events: Towards Developing Systems for Preventability.","authors":"Courage Edem Ketor, Charles Kwaku Benneh, Emmanuel Sarkodie, Juliet Ama Anaglo, Adelaide Mensah, Samuel Owusu Somuah, Selorm Akakpo, Eric Woode","doi":"10.1155/2024/1906797","DOIUrl":"10.1155/2024/1906797","url":null,"abstract":"<p><p><b>Background:</b> Analysing data on adverse drug reactions (ADRs) in health facilities is an essential step to help develop effective strategies to reduce their incidence. The objective was to analyse spontaneous ADR reports sent to the Ghanaian Food and Drugs Authority (FDA) by two reporting health facilities over 5 years. <b>Methods:</b> Data from duplicate spontaneous ADR reports sent to the FDA (Ghana) from 2014 to 2018 were extracted. The relationship between independent variables such as age, sex, and source of drugs and ADR outcomes was assessed with either chi-square or a Cramer's V test for association where appropriate. <b>Results:</b> Type A reactions (65.2%) were the most prevalent of the ADRs, followed by Type B (34.1%), with the majority (80%) of patients affected recovering fully. The majority of Type A reactions (54.1%) occurred in the clinic, while the majority of Type B reactions (43.5%) occurred in the hospital. The skin and central nervous system (CNS) were the most affected (70.8%) organs. A higher incidence of CNS and skin-related ADRs was recorded in patients older than 30 (RR = 1.28 (1.07-1.53)). Also, females were more likely to experience a CNS-related ADR. The seriousness of the ADR was found to be significantly associated with the (1) type of prescriber, (2) whether the drug was prescribed, or (3) whether the drug regimen prescribed was appropriate. Even though, in 86% of cases, the offending drug was withdrawn within the first 5 days, it exceeded 20 days in about 6% of cases. The record of allergy status in a patient's folder and the source of the drug were significantly associated with the chance that the offending drug was withdrawn. However, recording ADRs did not influence whether the offending drug was stopped. <b>Conclusion:</b> Most of the ADRs experienced by patients could be avoided if the current systems are improved to prevent the rechallenge of offending drugs. Efforts to improve and update patient medication records and steps to ensure continuity of care are essential in preventing these adverse drug events.</p>","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11379512/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142153119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Purpose: Dental reconstruction for patients diagnosed with severe mandibular bone atrophy using common dental implants is a challenging process. In such cases, surgeons may encounter challenges such as insufficient available bone, soft tissue, damage to the inferior alveolar nerve, and even the risk of bone fracture. In this study, a new design concept of mandibular patient-specific implants for severely atrophic ridges followed by finite element evaluation was presented to investigate the mechanical functionality of the concept. Method: The implant is comprised of two modular parts including an inferior border cover and a horseshoe-shaped structure. This horseshoe segment fits into the cover and is then screwed to it using two screws on each side. A 1 mm deflection was applied to a reference point located between the two anterior posts to extract the resulting Von Mises stress distribution in each part and the reaction force on the reference point which corresponds to the chewing force that the patient must apply to deform the horseshoe. This 1 mm gap is a design consideration and critical distance that horseshoe contacts the gingiva and disturbs the alveolar nerve. Results: The results revealed that load was transmitted from the horseshoe to the cover, and there were no stress contours on the body of the mandible. However, stress concentration was observed in screw locations in the mandible, the amount of which was decreased by increasing the number of used screws. In horseshoe, stress concentration values were around 350 MPa, and the measured reaction force on the reference point was just under 200 N. Conclusion: The finite element analysis results showed that this concept would be functional as the minimum load would be transmitted to the mandibular ridge, and since the patients diagnosed with atrophic ridge are not able to apply load to an amount near 200 N, the horseshoe would not contact the gingiva. Also, it is concluded that increasing the number of bone screw fixations would decrease the risk of long-term screw loosening.
目的:使用普通牙科种植体对被诊断为下颌骨严重萎缩的患者进行牙科重建是一个具有挑战性的过程。在这种情况下,外科医生可能会遇到可用骨量不足、软组织、下牙槽神经损伤甚至骨裂风险等挑战。本研究提出了一种针对严重萎缩牙脊的下颌特定患者种植体的新设计理念,并对其进行了有限元评估,以研究该理念的机械功能。方法:该种植体由两个模块组成,包括一个下缘盖和一个马蹄形结构。该马蹄形部分与下缘盖相吻合,然后通过两侧的两个螺钉将其拧紧。在位于两个前柱之间的参考点上施加 1 毫米的偏差,以提取每个部分的 Von Mises 应力分布以及参考点上的反作用力,该反作用力相当于患者必须施加的咀嚼力才能使马蹄形发生变形。这 1 毫米的间隙是设计时考虑的因素,也是马蹄铁接触牙龈和干扰牙槽神经的关键距离。结果结果显示,负荷从马蹄形传递到盖板,下颌骨体上没有应力轮廓。然而,在下颌骨的螺钉位置观察到了应力集中,随着使用螺钉数量的增加,应力集中的程度有所降低。在马蹄形部位,应力集中值约为 350 兆帕,在参考点测得的反作用力略低于 200 牛。结论有限元分析结果表明,这一概念是可行的,因为最小的负荷将传递到下颌嵴,而且由于被诊断为萎缩性嵴的患者无法施加接近 200 N 的负荷,马蹄形不会接触到牙龈。此外,结论是增加骨螺钉固定的次数可降低长期螺钉松动的风险。
{"title":"Finite Element Assessment of a Novel Patient-Specific Mandibular Implant for Severely Atrophic Ridge.","authors":"Alireza Parhiz, Reza Nourishirazi, Amirali Asadi, Morad Karimpour","doi":"10.1155/2024/9735427","DOIUrl":"10.1155/2024/9735427","url":null,"abstract":"<p><p><b>Purpose:</b> Dental reconstruction for patients diagnosed with severe mandibular bone atrophy using common dental implants is a challenging process. In such cases, surgeons may encounter challenges such as insufficient available bone, soft tissue, damage to the inferior alveolar nerve, and even the risk of bone fracture. In this study, a new design concept of mandibular patient-specific implants for severely atrophic ridges followed by finite element evaluation was presented to investigate the mechanical functionality of the concept. <b>Method:</b> The implant is comprised of two modular parts including an inferior border cover and a horseshoe-shaped structure. This horseshoe segment fits into the cover and is then screwed to it using two screws on each side. A 1 mm deflection was applied to a reference point located between the two anterior posts to extract the resulting Von Mises stress distribution in each part and the reaction force on the reference point which corresponds to the chewing force that the patient must apply to deform the horseshoe. This 1 mm gap is a design consideration and critical distance that horseshoe contacts the gingiva and disturbs the alveolar nerve. <b>Results:</b> The results revealed that load was transmitted from the horseshoe to the cover, and there were no stress contours on the body of the mandible. However, stress concentration was observed in screw locations in the mandible, the amount of which was decreased by increasing the number of used screws. In horseshoe, stress concentration values were around 350 MPa, and the measured reaction force on the reference point was just under 200 N. <b>Conclusion:</b> The finite element analysis results showed that this concept would be functional as the minimum load would be transmitted to the mandibular ridge, and since the patients diagnosed with atrophic ridge are not able to apply load to an amount near 200 N, the horseshoe would not contact the gingiva. Also, it is concluded that increasing the number of bone screw fixations would decrease the risk of long-term screw loosening.</p>","PeriodicalId":9007,"journal":{"name":"BioMed Research International","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11377113/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142139229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}