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1.
J Dent Sci ; 19(1): 357-363, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303871

RESUMO

Background/purpose: Current 3D-printing technology has been widely used for creating dental resin restorations. This study aimed to evaluate the effect of light intensity, time, and energy post-curing on the surface color of 3D-printed resin crowns. However, the influences of post-curing parameters on the restoration after printing still need to be explored. Therefore, this project investigates the effect of post-cure conditions on resin color. Materials and methods: Specimens from single-crown (SC) and pontic (PO) specimens underwent post-curing at various light intensities (105, 210, 420, 630, and 860 mW/cm2) for 5, 10, and 15 min. Specimens were observed at three predetermined points and measured using a commercial spectrophotometer that utilizes the CIE Lab∗ color space. Subsequently, samples were analyzed for color differences (ΔE). Results: ΔE color differences in evaluated samples were influenced by the light intensity, time, and energy post-curing. SC samples showed a significant color difference (P < 0.05), with the lowest value at 5 min of 16 (860 mW/cm2), while 10 and 15 min had a difference of 4 (210 mW/cm2). PO samples exhibited a significant decrease in the color difference (P < 0.05) at 5 and 10 min of 16 (860 mW/cm2), and at 15 min of 12 (630 mW/cm2). Conclusion: The results of this study indicate that exposing a resin crown to a high light intensity results in color stability and allows shorter post-curing times.

2.
J Dent Sci ; 19(1): 542-549, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303893

RESUMO

Background/purpose: Producing tooth crowns through dental technology is a basic function of dentistry. The morphology of tooth crowns is the most important parameter for evaluating its acceptability. The procedures were divided into four steps: tooth collection, scanning skills, use of mathematical methods and software, and machine learning calculation. Materials and methods: Dental plaster rods were prepared. The effective data collected were to classify 121 teeth (15th tooth position), 342 teeth (16th tooth position), 69 teeth (21st tooth position), and 89 teeth (43rd tooth position), for a total of 621 teeth. The procedures are divided into four steps: tooth collection, scanning skills, use of mathematical methods and software, and machine learning calculation. Results: The area under the curve (AUC) value was 0, 0.5, and 0.72 in this study. The precision rate and recall rate of micro-averaging/macro-averaging were 0.75/0.73 and 0.75/0.72. If we took a newly carved tooth picture into the program, the current effectiveness of machine learning was about 70%-75% to evaluate the quality of tooth morphology. Through the calculation and analysis of the two different concepts of micro-average/macro-average and AUC, similar values could be obtained. Conclusion: This study established a set of procedures that can judge the quality of hand-carved plaster sticks and teeth, and the accuracy rate is about 70%-75%. It is expected that this process can be used to assist dental technicians in judging the pros and cons of hand-carved plaster sticks and teeth, so as to help dental technicians to learn the tooth morphology more effectively.

3.
J Stomatol Oral Maxillofac Surg ; 125(6): 101766, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38286219

RESUMO

INTRODUCTION: Indonesia is a multicultural Asian country with a high incidence of cleft. This study contextualizes how patients' sociocultural backgrounds hinder cleft management in a diverse nation. MATERIAL AND METHODS: This study involved 202 families of cleft patients attending six tertiary care hospitals in South Sulawesi between 2021 and 2022. A mixed-methods, descriptive cross-sectional study employed semi-structured interviews and focus group discussions. Thematic content analysis was done using Murdock's causal attribution of illness. Knowledge of the treatments and surgery expectations used open coding. We held medical team focus group discussions to validate education on treatments. Cleft management education was thematically analyzed based on Indonesia's Minister of Health Decree. RESULTS: Two hundred-two families and ten medical teams participated. Thematic content analysis revealed common beliefs and factors that hinder medical treatments. The participants were 109 Buginese, 57 Makassarese, 16 Durinese, 8 Luwunese, 8 Torajanese, and 4 Mandarese. 22.3 % were unaware of causation, while 29.2 % attributed it to natural causes. About half of the interviewees believed in supernatural attribution. Even though 40 % of participants knew little about the surgery, they agreed that surgery improves appearance and speech. Medical treatments are delayed due to a lack of treatment knowledge, parents' concerns about surgical safety, and beliefs about causes. DISCUSSION: Indigenous societies in South Sulawesi believe in supernatural causes of cleft. Most had incomplete surgical treatment information. An intensive educational health program about causes, treatments, medical specialists, and treatment goals is warranted to enhance patient compliance with medical treatment, ultimately leading to improved health outcomes.

4.
JMIR Res Protoc ; 13: e42371, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38224475

RESUMO

BACKGROUND: Biphasic calcium phosphates (BCP) may serve as off-the-shelf alternatives for iliac crest-derived autologous bone in alveolar cleft reconstructions. To add osteoinductivity to the osteoconductive BCPs to achieve similar regenerative capacity as autologous bone, a locally harvested buccal fat pad will be mechanically fractionated to generate microfragmented fat (MFAT), which has been shown to have high regenerative capacity due to high pericyte and mesenchymal stem cell content and a preserved perivascular niche. OBJECTIVE: Our primary objectives will be to assess the feasibility and safety of the BCP-MFAT combination. The secondary objective will be efficacy, which will be evaluated using radiographic imaging and histological and histomorphometric evaluation of biopsies taken 6 months postoperatively, concomitant with dental implant placement. METHODS: Eight patients with alveolar cleft (≥15 years) will be included in this prospective, nonblinded, first-in-human clinical study. MFAT will be prepared intraoperatively from the patient's own buccal fat pad. Regular blood tests and physical examinations will be conducted, and any adverse events (AEs) or serious EAs (SAEs) will be meticulously recorded. Radiographic imaging will be performed prior to surgery and at regular intervals after reconstruction of the alveolar cleft with the BCP-MFAT combination. Biopsies obtained after 6 months with a trephine drill used to prepare the implantation site will be assessed with histological and histomorphometric analyses after methylmethacrylate embedding and sectioning. RESULTS: The primary outcome parameter will be safety after 6 months' follow-up, as monitored closely using possible occurrences of SAEs based on radiographic imaging, blood tests, and physical examinations. For efficacy, radiographic imaging will be used for clinical grading of the bone construct using the Bergland scale. In addition, bone parameters such as bone volume, osteoid volume, graft volume, and number of osteoclasts will be histomorphometrically quantified. Recruitment started in November 2019, and the trial is currently in the follow-up stage. This protocol's current version is 1.0, dated September 15, 2019. CONCLUSIONS: In this first-in-human study, not only safety but also the histologically and radiographically assessed regenerative potential of the BCP-MFAT combination will be evaluated in an alveolar cleft model. When an SAE occurs, it will be concluded that the BCP-MFAT combination is not yet safe in the current setting. Regarding AEs, if they do not occur at a higher frequency than that in patients treated with standard care (autologous bone) or can be resolved by noninvasive conventional methods (eg, with analgesics or antibiotics), the BCP-MFAT combination will be considered safe. In all other cases, the BCP-MFAT combination will not yet be considered safe. TRIAL REGISTRATION: Indonesia Clinical Trial Registry INA-EW74C1N; https://tinyurl.com/28tnrr64. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/42371.

5.
J Stomatol Oral Maxillofac Surg ; 125(3): 101685, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37967616

RESUMO

BACKGROUND: Dentigerous cysts are slow-growing, asymptomatic lesions that typically form around the crowns of impacted teeth. They are not detected until they start to harm the tissues around the teeth. AIM: The present study aimed to describe surgical techniques for treating dentigerous cysts associated with ectopic teeth. CASES: Three patients with dentigerous cysts associated with ectopic teeth, their surgical approaches, and the supporting literature are presented herein. In two cases, the surgical technique used was intra-oral, and in one case was extra-oral. Under general anesthesia, dentigerous cyst enucleation and ectopic tooth removal were carried out. DISCUSSION: In the present study, the ectopic tooth cases were all linked to dentigerous cysts. Enucleation or marsupialization treatments could be used to treat dentigerous cysts. Enucleation with the removal of the impacted tooth is the preferred treatment for dentigerous cysts. CONCLUSION: To perform minimally invasive surgery, the position of the ectopic teeth, the accessibility of the surgical site, the degree of bone reduction, and the simplicity of instrumentation should all be considered.

6.
Cleft Palate Craniofac J ; : 10556656231209823, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37899714

RESUMO

OBJECTIVE: This article examines and summarizes the published epidemiological literature on cross-cultural variations. Particular emphasis was put on addressing cross-cultural beliefs on the causes, management, and attitude toward cleft lip and/or cleft palate. A healthcare provider's awareness of these cross-cultural attitudes and beliefs is vital for promoting effective collaboration with patients' families and ensuring a favorable medical outcome. DESIGN: Systematic review. SETTING: Not applicable. PARTICIPANTS: Patients with cleft lip and/or cleft palate, their families, their communities, and healthcare providers. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Not applicable. RESULTS: All relevant and eligible studies were identified using PubMed and Google Scholar databases. The cultural belief was categorized and measured using Murdock's Theories of Illness. The study was reported in compliance with PRISMA guidelines. The quality of the selected studies was evaluated in accordance with the Critical Appraisal Skills Programme criteria (CASP). Fourteen articles covering thirteen countries on four continents met the inclusion criteria. In diverse communities, cleft lip and/or cleft palate was attributed to natural (infection, medication, improper diet, smoke, or radiation) or supernatural (God, eclipse, ancestral spirit, and curse) causes. Reported consequences include stigmatization, inappropriate treatments, leaving patients untreated, and infanticide. CONCLUSION: Cultural beliefs are the main cause of misconceptions surrounding a cleft lip and/or cleft palate. There is also a need for public health care providers' intervention to educate society about the natural causes and ease of management, thereby increasing opportunities for patients substantially.

7.
Cleft Palate Craniofac J ; : 10556656231199648, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37654054

RESUMO

Cases of severe bilateral Tessier 4 cleft with unilateral Tessier 3 cleft and additional involvement of the amniotic band syndrome are rarer. This case reports a very rare case of ABS with severe facial cleft. Postoperative progress was satisfactory and the patient achieved functional recovery. The patient underwent several miner reconstructive surgeries and appropriate surgical treatment is necessary to restore the patient's social life.

8.
Polymers (Basel) ; 15(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37571117

RESUMO

The present study was conducted to manipulate various biomaterials to find potential hydrogel formulations through three-dimensional (3D) bioprinting fabrication for tissue repair, reconstruction, or regeneration. The hydrogels were prepared using sodium alginate and gelatin combined with different concentrations of Pluronic F127 (6% (3 g), 8% (4 g), and 10% (5 g)) and were marked as AGF-6%, AGF-8%, and AGF-10%, respectively. The properties of the hydrogels were investigated using a contact angle goniometer, rheometer, and 3D bioprinter. In addition, the osteoblast-like cell line (MG-63) was used to evaluate the cell viability including hydrogels before and after 3D bioprinting. It was found that the ratio of contact angle was lowest at AGF-6%, and the rheological results were higher for all samples of AGF-6%, AGF-8%, and AGF-10% compared with the control sample. The printability indicated that the AGF-6% hydrogel possessed great potential in creating a cell scaffold with shape integrity. Moreover, the live/dead assay also presented the highest numbers of live cells before printing compared with after printing. However, the number of live cells on day 7 was higher than on day 1 before and after printing (** p < 0.01). Therefore, the combination of AGF-6% could be developed as a biofunctional hydrogel formulation for potential tissue regeneration applications.

9.
J Dent Sci ; 18(3): 1227-1234, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37404638

RESUMO

Background/purpose: Immediate implant placement in the mandibular anterior tooth region requires a thorough understanding of the alveolar bone anatomy for determining the ideal implant position and preventing labial bone perforation. The anatomical characteristics of the jaws are closely related to the sagittal root position (SRP) and labial concavity of the alveolar bone. This study evaluated SRP, labial concavity, and labial bone perforation in the mandibular anterior tooth region. Materials and methods: Cone-beam computed tomography images of 116 participants (696 teeth) were uploaded to medical imaging software. SRP classification, labial concavity of the alveolar bone, and labial bone perforation were analyzed. A t-test was performed to compare measurements between the central and lateral incisors, central incisors and canines, and lateral incisors and canines. Results: The results revealed that the frequency of SRP Class I (88.20%) was the highest, and that of SRP Class III was the lowest (0.53%). Central incisors had the highest mean labial concavity (144.5°), followed by the canines (143.9°) and lateral incisors (143.3°), and the differences were significant between any two of the tooth groups (all P < 0.05). The frequency distribution of labial bone perforation was the highest in central incisors (69.9%), followed by the canines (40.5%) and lateral incisors (10.8%). Conclusion: The majority of mandibular anterior teeth had SRP Class I, with Class III being the least prevalent. Central incisors had the highest mean alveolar bone concavity angle and the most frequent labial bone perforations.

10.
Sci Rep ; 13(1): 8445, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231111

RESUMO

Multiple treatment approaches have been undertaken to reduce the incidence of recurrence in solid/multicystic ameloblastoma (SMA), both conservative and radical. A network meta-analysis (NMA) was conducted to assess and compare the effectiveness of these various treatment approaches concurrently. This study was reported based on the Preferred Reporting Items for Systematic Reviews for Network Meta-Analysis (PRISMA-NMA) statement. PubMed (MEDLINE), ScienceDirect, Scopus, and Web of Science were searched until August 10, 2021. The NMA was conducted using the STATA program. Of 1153 records identified in the search, seven observational studies with 180 patients were included. Six different treatment approaches were identified. Segmental resection ranked highest for reducing the recurrence rate with the highest SUCRA score (77.7), followed by curettage with cryotherapy (66.9) and marginal resection (49.3). Network inconsistencies and publication bias appeared to be absent. According to the Confidence in Network Meta-Analysis (CINeMa) method, the evidence's certainty was low for all comparisons due to imprecision and within-study bias. In conclusion, this study is the first NMA in the field of ameloblastoma. Segmental resection seemed to be the most effective treatment approach for minimizing recurrence in SMA patients. Nevertheless, weak certainty of evidence makes that the results must be regarded with caution.


Assuntos
Ameloblastoma , Humanos , Metanálise em Rede , Ameloblastoma/cirurgia , Resultado do Tratamento , Viés
11.
Cleft Palate Craniofac J ; : 10556656231175278, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37203174

RESUMO

This study aimed to analyze the efficacy of stem cell-based tissue engineering for the treatment of alveolar cleft (AC) and cleft palate (CP) defects in animal models.Systematic review and meta-analysis.Preclinical studies on alveolar cleft repair in maxillofacial practice.Electronic search was performed using PubMed, Embase, and Cochrane databases. Pre-clinical studies, where stem cell-based tissue engineering was used in the reconstruction of AC and CP in animal models were included. Quality of the selected articles was evaluated using SYRCLE (SYstematic Review Centre for Laboratory animal Experimentation).Review of alveolar cleft bone augmentation interventions in preclinical models.Outcome parameters registered were new bone formation (NBF) and/or bone mineral density (BMD).Thirteen large and twelve small animal studies on AC (21) and CP (4) reconstructions were included. Studies had an unclear-to-high risk of bias. Bone marrow mesenchymal stem cells were the most widely used cell source. Meta-analyses for AC indicated non-significant benefits in favor of: (1) scaffold + cells over scaffold-only (NBF P = .13); and (2) scaffold + cells over empty control (NBF P = .66; BMD P = .31). Interestingly, dog studies using regenerative grafts showed similar to superior bone formation compared to autografts. Meta analysis for the CP group was not possible.AC and CP reconstructions are enhanced by addition of osteogenic cells to biomaterials. Directions and estimates of treatment effect are useful to predict therapeutic efficacy and guide future clinical trials of bone tissue engineering.

12.
Cleft Palate Craniofac J ; : 10556656231171210, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37097837

RESUMO

OBJECTIVE: To evaluate the outcomes of Secondary Alveolar Bone Grafting (SABG) in patients treated either in daycare or with multiple day hospitalization (MDH) in relation to costs and complication rates. DESIGN: Retrospective comparative cohort study. SETTING: The data was collected from two settings: Postoperative daycare or MDH after oral cleft surgery in an Academic Medical Center in The Netherlands. PATIENTS: Data of 137 patients with unilateral Cleft lip, alveolus, and palate (CLAP) treated between 2006-2018 were evaluated. Registered clinical variables: age, gender, cleft subtype, bone donor site, type of hospitalization, length of stay, additional surgery, complications, surgeons, and costs. INTERVENTIONS: Closure of the alveolar cleft with/without closure of the anterior palate. MAIN OUTCOME MEASURES: Univariate analyses. RESULTS: Of the 137 patients, 46.7% were treated in MDH, and 53.3% in daycare. Total costs for daycare were significantly lower (P < .001). All patients treated in daycare received mandibular symphysis bone, whereas in MDH, 46.9% received iliac crest bone instead. Bone donor site was associated with postoperative care type. Complication rates were slightly but not significantly higher in daycare (26%) vs. MDH (14.1%) (P = .09). Most were Grade I (minor) according to Clavien Dindo classification. CONCLUSIONS: Daycare after alveolar cleft surgery is about as safe as MDH, but significantly cheaper.

13.
J Chin Med Assoc ; 86(6): 565-570, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37071771

RESUMO

BACKGROUND: The anatomical characteristics of the maxillary labial alveolar bone play a crucial role in the treatment planning of immediate implant placement. The sagittal root position (SRP) and alveolar bone concavity are closely related to anatomical characteristics in determining the ideal implant position. This study evaluated the SRP and labial alveolar bone concavity in the maxillary anterior teeth area. METHODS: Cone-beam computed tomography images of 120 samples involving 720 teeth were uploaded to the medical imaging software. The SRP was classified as Class I, II, III, or IV, and the concavity of labial alveolar bone was measured. A T test was performed to compare measurements between the central and lateral incisors, between the central incisors and canines, and between the lateral incisors and canine. RESULTS: The majority of the SRPs of the maxillary anterior teeth were class I (engaging the labial cortical plate) with frequencies of 98.3%, 85.8%, and 81.7% for the canines, lateral incisors, and central incisors, respectively. In terms of concavity of labial alveolar bone in maxillary tooth area, canines also had the largest mean value (139.5°), followed by lateral incisors, whereas central incisors has the smallest mean value (131.7°). The results of the T test revealed a significant difference ( p < 0.001) in labial alveolar bone concavity between central and lateral incisors, between central incisors and canines, and between lateral incisors and canines. CONCLUSION: Most maxillary anterior teeth were classified as Class I SRP, Class III SRP was the least prevalent, and the concavity of the labial alveolar bone significantly differed between the central and lateral incisors, between the central incisors and canines, and between the lateral incisors and canines. In addition, the canines had the highest mean alveolar bone concavity angle, indicating that less concavity in the canines area.


Assuntos
Processo Alveolar , Incisivo , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/cirurgia , Incisivo/diagnóstico por imagem , Incisivo/cirurgia , Tomografia Computadorizada de Feixe Cônico , Maxila/diagnóstico por imagem
15.
Oral Maxillofac Surg ; 27(3): 479-487, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35715707

RESUMO

INTRODUCTION: Odontoma is the most commonly diagnosed odontogenic tumor of the oral cavity. The objective of the present study was to assess the demographic variables, patterns, diagnostic features, and management issues of odontomas treated at several European departments of maxillofacial and oral surgery. MATERIALS AND METHODS: This study was conducted at 8 European departments of oral surgery between January 1, 2004, and December 31, 2018. Only patients with odontomas were included. The following data were recorded for each patient: gender, age, comorbidities, site, size of odontomas, radiographic features, type of odontoma, treatment of odontomas, treatment of associated teeth, complications, and recurrence. RESULTS: A total of 127 patients (70 male and 57 female patients) with odontomas were included. The mean age was 22 years; 71 odontomas were found in the mandible, whereas 56 in the maxilla. In the mandible, the most frequently involved subsite was the parasymphysis, while in the maxilla, the most common subsite was the upper incisor region. The mean size of included odontomas was 15.3 mm. On the whole, 62 complex odontomas, 50 compound odontomas, and 15 mixed-type odontomas were observed. Complete excision of the odontomas was performed in 121 patients. In 24 patients, the extraction of deciduous teeth was performed, and in 43 patients, one or more permanent teeth were removed. Finally, in 9 patients, a partial excision of the odontoma was performed. Recurrence was observed in 4 cases out of 127 patients. CONCLUSIONS: Dental practitioners should be aware of the distinct clinical and radiographic features of odontoma in order to perform an appropriate and early diagnosis. Conventional radiography, such as panoramic radiograph, is often sufficient technique for a diagnosis after clinical suspicion or for an incidental diagnosis to prevent later complications, such as impaction or failure of eruption of teeth.


Assuntos
Odontoma , Dente Impactado , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Odontoma/diagnóstico por imagem , Odontoma/epidemiologia , Odontólogos , Papel Profissional , Dente Impactado/cirurgia , Maxila
16.
Heliyon ; 8(9): e10810, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36200020

RESUMO

Tetanus is an acute and vaccine-preventable disease caused by anaerobic bacteria, Clostridium tetani. This bacterium can enter the human body via a deep wound, burn injury or medical procedure; however, certain cases also originate from odontogenic infection. In the present study, a tetanus infection associated with dental origin in a 44-year-old man is reported. The case was complicated by lockjaw and difficulty swallowing that worsened over a few days, followed by a generalized spasm. Furthermore, a literature review was performed, in which six reported cases of tetanus, presumed to be of dental or oral origin, were identified between 2011and 2021. General practitioners, especially dentists, should be aware of tetanus associated with odontogenic origin even without a history of an external penetrating wound or other medical procedures:.

17.
J Clin Exp Dent ; 14(8): e608-e614, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36046168

RESUMO

Background: Surgical procedures including palatoplasty have a risk for complications. The aim of this study was to investigate the intraoperative and early postoperative blood loss using the buccal fat pad (BFP) during cleft lip and/or cleft palate (CL/P) surgery. Material and Methods: This prospective study included a total of 109 patients with cleft palate (CP) during a three-month period of treatment at Hasanuddin University Dental Hospital (permanent center) and charity trips in rural parts of Eastern Indonesia. All patients were treated with DOZ Furlow technique combined with BFP graft. Before and after surgery, the total amount of intraoperative blood loss was calculated by measuring the weight differences of the gauze swabs that were used to control the surgical bleeding followed by a complete blood count at three days postoperatively. Results: The difference in the amount of blood loss based on age categories in charity groups was found to be significant (P<0.05). Overall, we found that high body weight and operation time significantly contributed to increased blood loss (P<0.05). Conclusions: Weight and operative time can contribute to more blood loss during palatoplasty. Key words:Buccal fat pad, complication, cleft lip, cleft palate, palatoplasty.

18.
Polymers (Basel) ; 14(7)2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35406340

RESUMO

In this study, we designed and fabricated transmission parts for a flapping-wing micro-aerial vehicle (FW-MAV), which was fabricated by precision injection molding, and analyzed its warpage phenomena. First, a numerical simulation (Moldflow) was used to analyze the runner balance and temperature, pressure, and stress distributions of the base, gears, and linkage of the transmission structures in an FW-MAV. These data were then applied to fabricate a steel mold for an FW-MAV. Various process parameters (i.e., injection temperature, mold temperature, injection pressure, and packing time) for manufacturing transmission parts for the FW-MAV by precision injection molding were compared. The Taguchi method was employed to determine causes of warpage in the transmission parts. The experimental results revealed that the causes of warpage in the transmission parts were, in order of importance, the mold temperature, injection pressure, packing time, and injection temperature. After the transmission parts were assembled on the FW-MAV, experiments revealed that the MAV could achieve a flight time of 180 s. Mass production of the FW-MAV by precision injection molding could potentially produce substantial savings in time, manpower, and cost.

19.
Biomed Rep ; 16(5): 35, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35386105

RESUMO

The present study aimed to assess the incidence of the vitamin D receptor (VDR) gene polymorphism TaqI in patients with periodontitis, and the potential association of this polymorphism with the severity of the disease. This was a case-controlled study, which included 162 adults divided into two groups as follows: Case group (81 patients diagnosed with periodontitis) and control group (81 patients without periodontitis). Venous blood was obtained from each sample from which DNA was extracted. The gene polymorphism was determined using restricted fragment length polymorphism-PCR and DNA sequencing to identify endonuclease restrictions in exon 9 (TaqI). The data were analyzed using an independent samples t-test. VDR gene polymorphisms were detected in periodontitis cases with TT (86.4%), Tt (12.4%) and tt (1.2%) genotypes. DNA sequencing confirmed a change in the sequence of the VDR gene nucleotides in patients with periodontitis. The data indicated that the severity of periodontal tissue damage may be influenced by changes in the nucleotide sequence.

20.
J Clin Exp Dent ; 14(3): e247-e253, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35317299

RESUMO

Background: Diagnosis of jaw cysts is challenging in general dental practice, and most cases are incidentally discovered through routine dental radiography. The aim of this study was to examine the epidemiology and treatment of odontogenic and non-odontogenic cysts to better understand the status of these lesions in populations in South Sulawesi, Indonesia. Material and Methods: This retrospective study was conducted on patients treated at four different hospitals in Makassar between January 2011 and June 2017. Patients diagnosed as having odontogenic or non-odontogenic cysts were included in the study. Information on variables such as sex, age, histopathological, and anatomical distributions was collected. Statistical analyses were performed using an independent T-test and the Pearson chi-square test (p< 0.05). Results: A total of 173 samples were collected, of which only 60 were histopathologically analyzed. The patients' mean age was 30.3 years. The cysts occurred more frequently in women and in the anterior maxilla, followed by the posterior mandible. The radicular cyst was the most prevalent type, followed by the dentigerous cyst. Most cysts were treated with enucleation. Of the patients, 72.8% were followed up, of whom 3.2% had a recurrence and only 19.1% had complaints of clinical symptoms. Conclusions: Our findings indicate that odontogenic and non-odontogenic cysts widely vary in terms of incidence, with some exhibiting a predilection for specific ages and sites and specific sex. Knowledge of these factors could be useful for both clinicians and pathologists in the diagnosis and choice of the appropriate treatment plan. Key words:Cyst, epidemiology, odontogenic, non-odontogenic, treatment.

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