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1.
Clin Implant Dent Relat Res ; 26(3): 621-630, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38556885

RESUMO

BACKGROUND: Using the sandwich osteotomy technique in the posterior mandible is delicate. This study aimed to assess the safety and the amount of bone gain using a full digital workflow versus the conventional procedure. PATIENTS AND METHODS: This split mouth study included 10 patients with bilateral vertically deficient posterior mandible. One side received conventional sandwich interpositional bone grafting (control group), while the other side received the same protocol using two patient-specific guides. The first guide (cutting guide) was used to place the osteotomies safely and accurately according to the predetermined dimensions and locations, and the second guide was used to fix the mobilized bony segment, leaving the desired gap to be filled with a particulate xenogenic bone graft. RESULTS: Full neurosensory recovery was documented at 2 months postoperative for all patients and bilaterally. After 4 months, there was a statistically significant difference in vertical bone gain between both groups (p = 0.001), measuring an average of 3.76 ± 0.72 mm in the study group and 2.69 ± 0.37 mm in the control group. No statistically significant difference was found between the planned vertical augmentation (3.85 ± 0.58 mm) and the obtained vertical bone gain (3.76 ± 0.72 mm) in the study group (p = 0.765) proving the accuracy of the guided procedure. CONCLUSION: Computer-guided sandwich interpositional grafting is predictable regarding the execution of the osteotomies and the accuracy of fixation of the transport segment.


Assuntos
Mandíbula , Osteotomia , Humanos , Masculino , Feminino , Mandíbula/cirurgia , Adulto , Osteotomia/métodos , Pessoa de Meia-Idade , Fluxo de Trabalho , Transplante Ósseo/métodos , Aumento do Rebordo Alveolar/métodos , Cirurgia Assistida por Computador/métodos
2.
Int J Implant Dent ; 9(1): 41, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37917214

RESUMO

PURPOSE: To evaluate the effectiveness of using Densah burs for lifting the maxillary sinus membrane in cases with an oblique sinus floor with a residual bone height of 4-7 mm. METHODS: The study was conducted on 16 patients, comprising 9 males and 7 females, aged 25-60 years, split into two groups of 8 each: group I with a residual bone height of 4-5.5 mm below the sinus floor and group II with a residual bone height of 5.5-7 mm. Exclusion criteria included smokers, presence of systemic or metabolic conditions that contraindicate implant placement and a local sinus pathology. The study involved the use of Densah burs, using the osseodensification concept to elevate the sinus floor, along with simultaneous dental implant placement. The integrity of the sinus membrane was verified via clinical examination and a confirmatory cone beam computed tomography scan. RESULTS: The study revealed that out of the 16 cases, one case had a sinus membrane perforation, confirmed clinically at the time of the operation. The study achieved a mean lift of 4.42 mm and a mean final seating torque of 35.5 N/cm. At the 1-year follow-up, all cases showed clinical success, with no signs of sinus pathology or complications. CONCLUSIONS: In cases with oblique sinus floors and a residual bone height of 4-7 mm in moderately atrophic posterior maxilla, the osseodensification concept proved to be a safe and effective method for performing sinus lift procedures with simultaneous implantation.


Assuntos
Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Masculino , Feminino , Humanos , Implantação Dentária Endóssea/métodos , Levantamento do Assoalho do Seio Maxilar/métodos , Estudos Prospectivos , Transplante Ósseo/métodos
3.
Vaccines (Basel) ; 11(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36851216

RESUMO

Vaccination remains the leading control method against infectious bronchitis (IB) in poultry despite the frequently observed IB outbreaks in vaccinated flocks. Here, two vaccination regimes were evaluated against challenge with the Massachusetts (Mass) infectious bronchitis virus (IBV) strain that was linked to egg production defects in Western Canada. One vaccination strategy included live attenuated IB vaccines only, and the other used both inactivated and live attenuated IB vaccines. The two immunization programs involved priming with a monovalent live attenuated IB vaccine (Mass serotype) at day-old, followed by intervals of bivalent live attenuated IB vaccines containing the Mass and Connecticut (Conn) serotypes given to the pullets at 2-, 5-, 9-, and 14-week-old. Inactivated IB vaccine (Mass serotype) was administrated to only one group of the vaccinated birds at 14-week-old. At the peak of lay, the hens were challenged with the Mass IBV isolate (15AB-01) via the oculo-nasal route. The efficacy of the vaccines was assessed following the challenge by observing clinical signs, egg production, egg quality parameters, seroconversion, and systemic T-cell subsets (CD4+ and CD8+ cells). Moreover, the viral genome loads in the oropharyngeal (OP) and cloacal (CL) swabs were quantified at predetermined time points. At 14 days post-infection (dpi), all the hens were euthanized, and different tissues were collected for genome load quantification and histopathological examination. Post-challenge, both vaccination regimes showed protection against clinical signs and exhibited significantly higher albumen parameters, higher anti-IBV serum antibodies, and significantly lower levels of IBV genome loads in OP swabs (at 3 and 7 dpi) and trachea and cecal tonsils compared to the mock-vaccinated challenged group. However, only the birds that received live attenuated plus inactivated IB vaccines had significantly lower IBV genome loads in CL swabs at 7 dpi, as well as decreased histopathological lesion scores and IBV genome loads in magnum compared to the mock-vaccinated challenged group, suggesting a slightly better performance for using live attenuated and inactivated IB vaccines in combination. Overall, the present findings show no significant difference in protection between the two vaccination regimes against the Mass IBV challenge in laying hens.

4.
Oral Maxillofac Surg ; 27(3): 469-478, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35695945

RESUMO

PURPOSE: The present study compared the absorbable gelatin sponge as a space-filling material versus anorganic bone bovine mineral (ABBM) in maxillary sinus augmentation with simultaneous endosseous dental implant placement. METHODS: Eighteen maxillary sinus floor elevation cases were randomly allocated into two groups. The first group received ABBM, while the second group received an absorbable gelatin sponge as a space-filling material. For both groups, CBCT scans were obtained immediately postoperatively and six months later to calculate the difference in sinus floor bone gain. Osstell readings were recorded both at the time of implant placement and implant exposure with a total of twenty-three dental implant placements in relation to the eighteen elevated sinus floors. RESULTS: The mean radiographic sinus floor gain in the ABBM group was 10.2 mm (± 2.5), while in the absorbable gelatin sponge group was 5.4 mm (± 2.0), with a mean difference of 4.8, which was statistically significant (p < 0.001). The mean implant stability for the ABBM was 77.3 (± 4.9), while in the absorbable gelatin sponge group was 74.2 (± 3.0), with a mean difference of 3.1, which was statistically insignificant (p = 0.1610). CONCLUSION: The ABBM showed superior results regarding the amount of radiographic sinus floor bone gain. However, the implant stability was invariable between both groups.


Assuntos
Substitutos Ósseos , Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Humanos , Bovinos , Animais , Levantamento do Assoalho do Seio Maxilar/métodos , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia , Esponja de Gelatina Absorvível , Implantação Dentária Endóssea/métodos , Transplante Ósseo/métodos , Minerais
5.
Clin Implant Dent Relat Res ; 25(1): 77-86, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36239176

RESUMO

BACKGROUND: The sandwich osteotomy technique usually requires high surgical skills and prolonged intraoperative time and had some technical drawbacks with a subsequent deficient amount of vertical bone gain. The aim of this study was to evaluate the final vertical bone gain using sandwich osteotomy with simultaneous versus delayed implant placement in the anterior maxilla. MATERIAL AND METHODS: This study included 16 patients having multiple missing maxillary anterior teeth with a vertically deficient alveolar ridge. Patients were randomly assigned into two equal groups. Both groups were treated using sandwich osteotomy with interpositional particulate bovine bone graft. In the study group (8 patients, 17 implants), the transport mobilized bone segment was fixed in position using simultaneous implant placement. Whereas in the control group (8 patients, 18 implants), micro-plates and screws were used, followed by a second-stage surgery for plates removal and delayed implant placement. Radiographic assessment included 4 months postoperative mean of vertical gain in alveolar ridge height, taken from cross-sectional cuts of cone beam CT. RESULTS: The mean vertical bone gain in the study group was 4.04 ± 0.59 mm compared to 3.86 ± 0.52 mm in the control group with no statistically significant difference (p = 0.518). The mean value of bone gain percentage in the study group was 33.02% compared to 31.75% in the control group, with no statistically significant difference (p = 0.656). CONCLUSION: The sandwich osteotomy technique with simultaneous implant placement is a reliable method for vertical ridge augmentation that eliminates the need for a secondary surgery.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Humanos , Animais , Bovinos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Aumento do Rebordo Alveolar/métodos , Estudos Transversais , Transplante Ósseo/métodos , Osteotomia/métodos , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/cirurgia , Implantação Dentária Endóssea/métodos
6.
Int J Oral Maxillofac Implants ; 38(2): 295-302, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36219140

RESUMO

PURPOSE: To assess the radiographic and histomorphometric outcomes of horizontally augmented maxillary alveolar ridges using solid nonperforated customized titanium barriers. MATERIALS AND METHODS: This case series study included patients who received guided bone regeneration treatment in the anterior maxillary esthetic zone (eight patients, 18 dental implants) using patient-specific solid titanium barriers loaded with a mix of autogenous and xenogenic particulate bone grafts. A radiographic comparison between three time periods (immediately postoperative, 4 months, and 10 months) included software-aided calibration of the linear changes in the horizontal dimensions on CBCT cross-sectional cuts after being standardized. Bone core specimens were retrieved for histomorphometric analysis by the time of implant insertion. RESULTS: Wound healing was uneventful, except for two patients who showed soft tissue breakdown that did not affect the outcome. There was a statistically significant difference between the mean horizontal bone change at the different time intervals (P < .001), with a 79.6% ± 29.2% mean area of newly formed bone. CONCLUSION: GBR using customized solid titanium barriers appears to be efficient and promising concerning the final horizontal bone gain and the quality of the augmented sites.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Humanos , Implantação Dentária Endóssea/métodos , Titânio , Aumento do Rebordo Alveolar/métodos , Estudos Transversais , Estética Dentária , Regeneração Óssea , Transplante Ósseo/métodos
7.
Genes (Basel) ; 13(9)2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36140785

RESUMO

Genetic diversity and evolution of infectious bronchitis virus (IBV) are mainly impacted by mutations in the spike 1 (S1) gene. This study focused on whole genome sequencing of an IBV isolate (IBV/Ck/Can/2558004), which represents strains highly prevalent in Canadian commercial poultry, especially concerning features related to its S1 gene and protein sequences. Based on the phylogeny of the S1 gene, IBV/Ck/Can/2558004 belongs to the GI-17 lineage. According to S1 gene and protein pairwise alignment, IBV/Ck/Can/2558004 had 99.44-99.63% and 98.88-99.25% nucleotide (nt) and deduced amino acid (aa) identities, respectively, with five Canadian Delmarva (DMV/1639) IBVs isolated in 2019, and it also shared 96.63-97.69% and 94.78-97.20% nt and aa similarities with US DMV/1639 IBVs isolated in 2011 and 2019, respectively. Further homology analysis of aa sequences showed the existence of some aa substitutions in the hypervariable regions (HVRs) of the S1 protein of IBV/Ck/Can/2558004 compared to US DMV/1639 isolates; most of these variant aa residues have been subjected to positive selection pressure. Predictive analysis of potential N-glycosylation and phosphorylation motifs showed either loss or acquisition in the S1 glycoprotein of IBV/Ck/Can/2558004 compared to S1 of US DMV/1639 IBV. Furthermore, bioinformatic analysis showed some of the aa changes within the S1 protein of IBV/Ck/Can/2558004 have been predicted to impact the function and structure of the S1 protein, potentially leading to a lower binding affinity of the S1 protein to its relevant ligand (sialic acid). In conclusion, these findings revealed that the DMV/1639 IBV isolates are under continuous evolution among Canadian poultry.


Assuntos
Infecções por Coronavirus , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Aminoácidos/genética , Animais , Canadá , Galinhas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Genótipo , Glicoproteínas/genética , Vírus da Bronquite Infecciosa/genética , Ligantes , Ácido N-Acetilneuramínico , Nucleotídeos , Aves Domésticas
8.
Expert Rev Gastroenterol Hepatol ; 16(3): 217-233, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35184616

RESUMO

INTRODUCTION: Gastro-esophageal reflux disease (GERD) is a common gastrointestinal disorder that occurs when backflow of the gastric contents into the esophagus results in troublesome symptoms. Though GERD has been extensively studied in Western populations, literature on the management of GERD in patients in Africa and Middle East (AME) is scarce. AREAS COVERED: In this review, we provide an overview of the management of mild-to-moderate GERD in AME. Here we focus on the efficacy and safety of currently available treatments for GERD to help physicians and community pharmacists appropriately manage patients with mild-to-moderate GERD in the primary healthcare setting, detailing specific situations and patient scenarios that are relevant to the region, including management of GERD during Ramadan and post-bariatric surgery. EXPERT OPINION: Under-appreciation of the burden of GERD in the region has resulted in a lack of consensus on management. Barriers that currently prevent the adoption of treatment guidelines in the primary healthcare setting may include lack of availability of local guidelines and referral systems, a paucity of region-specific research, and dogmatic adherence to traditional practice. By increasing awareness, strengthening knowledge, and by more effective utilization of resources, physicians and pharmacists could optimize GERD management strategies to better support patients.


Assuntos
Gastroenterologistas , Refluxo Gastroesofágico , África/epidemiologia , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/terapia , Humanos , Oriente Médio
9.
Oral Maxillofac Surg ; 26(2): 299-309, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34328575

RESUMO

BACKGROUND: This study aims to prospect the soft and hard tissue changes after augmentation of two different local mandibular contour defects using polyetheretherketone (PEEK) patient-specific onlay implants. METHODS: Six patients with disfiguring local mandibular deformities were included in this study (five males and one female) and received seven PEEK patient-specific implants (PSI), virtually designed and surgically settled to augment seven mandibular defects, three deficient chins, and four mandibular angels. The analysis of the soft and hard tissue changes utilized the superimposition of the preoperative and the 6-month postoperative sagittal and coronal CT views, after standardizing the radiographic interpretation. RESULTS: The soft tissue gain for the chin was 6.8 mm ± 0.98 with a 45.8% increase versus 4.42 mm ± 0.41 with a 22.9% increase for the angle. The difference in the soft tissue gain between the two groups was statistically significant (P = 0.0001). Comparing the soft tissue gain to the planned implant thickness, the percentage of the soft tissue gain for the chin recorded 109.2% versus 65.57% for the angle. The difference between the two groups was also statistically significant (P < 0.0001). CONCLUSION: PEEK patient-specific onlay implants represented an efficient and straightforward modality to augment local mandibular contour deformities with favorable esthetic outcomes; the total soft tissue profile gain of the chin region markedly exceeded that of the mandibular angle.


Assuntos
Implantes Dentários , Benzofenonas , Estética Dentária , Feminino , Humanos , Cetonas , Masculino , Polietilenoglicóis , Polímeros
10.
Clin Implant Dent Relat Res ; 23(6): 842-850, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34609058

RESUMO

BACKGROUND: Sandwich osteotomy technique (Inlay bone grafting) is considered as a highly reliable procedure for vertical bone augmentation in the maxillary anterior esthetic zone. The aim of this study was to compare vertical bone gain and palatal tipping using computer-guided inlay technique versus the conventional technique. MATERIAL AND METHODS: This was a randomized clinical trial including 12 patients who were randomly divided into two groups: sandwich osteotomy with simultaneous implant placement at the anterior maxillary esthetic zone (six patients) using patient-specific guides (PSGs) in the study group versus conventional technique (six patients). In the control group, free-hand sandwich osteotomy was done, while in the study group all the procedures were performed with two sequential PSGs with cutting slits, guiding holes, and implant sleeves. Radiographic assessment included measurements of linear changes in the vertical dimensions of the labial plate of bone and palatal tipping on cross-sectional cuts of cone-beam computed tomography using special software. RESULTS: All the procedures were uneventful except one case of the study group showed a cracked bony segment that did not affect the final outcome. Radiographic results showed comparable bone gain in both groups with no statistical significance difference (study group 4.4 mm, control group 3.9 mm). To the contrary, the computer-guided approach significantly reduced the palatal tipping to 0.4 mm compared to 2.1 mm in the conventional group, and there was a statistically significant difference between the two groups (p-value <0.001). CONCLUSION: Sandwich osteotomy using PSGs appears to be efficient and showed promising results regarding improving the palatal tipping compared to the free-hand technique.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Transplante Ósseo , Computadores , Estudos Transversais , Implantação Dentária Endóssea , Estética Dentária , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Osteotomia , Projetos Piloto
11.
Vet World ; 14(8): 2131-2141, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34566331

RESUMO

BACKGROUND AND AIM: Highly pathogenic avian influenza H5N8 virus of clade 2.3.4.4 was newly emerged to Egypt and firstly detected in carcasses of wild birds in November 2016. This study assessed the protection efficacy and virus shedding reduction of three different inactivated avian influenza (AI) H5 (H5N1, H5N2, and H5N3) commercial vaccines against challenge with two newly emerging highly pathogenic AI virus H5N8 Egyptian isolates in specific-pathogen-free (SPF) chicks. MATERIALS AND METHODS: 10-day-old SPF chicks (n=260) were divided into 20 groups (n=13). Groups 1-5 were vaccinated through the subcutaneous route (S/C) with 0.5 mL of H5N1 vaccine, Groups 6-10 were vaccinated (S/C) with 0.5 mL of H5N2 vaccine, and Groups 11-15 were vaccinated (S/C) with 0.5 mL of H5N3 vaccine. Positive control groups (16-19) were challenged at 25 and 31 days old (2 and 3 weeks post-vaccination [PV]) using H5N8 clade 2.3.4.4 A/duck/Egypt/F13666A/2017(H5N8) and H5N8 clade 2.3.4.4 A/chicken/Egypt/18FL6/2018(H5N8). Group 20 was left non-vaccinated as a control. All vaccinated groups were divided and challenged with both viruses at 25 and 31 days of age. The viral challenge dose was 0.1 mL of 106 EID50/0.1 mL titer/chick, and it was administered oronasally. All chicks were kept in isolators for 14 days after each challenge. Sera samples were collected weekly and at 2 weeks post-challenge (PC) to detect a humoral immune response. PC mortalities were recorded daily for 10 days to calculate the protection percentages. Tracheal swabs were collected from the challenged chicks in different groups at 3, 5, 7, and 10 days PC. Kidneys and spleens were collected at 3, 5, 7, and 10 days PC and kept in formalin for histopathological examination to assess lesions and severity scores. Tracheal swabs were inoculated in 10-day-old SPF embryonated chicken eggs for virus titration and to calculate shedding levels. RESULTS: All studied vaccines displayed 70-100% protection within 10 days PC. Hemagglutination inhibition results from sera samples revealed antibody titers ranging from 0.6 to 5.4 log2 starting at 1-week PV with the highest titers at 4 weeks PV. Challenged SPF chickens exhibited a notable reduction in virus shedding, with an average of 1.5-2 log10, compared to control birds. Various histopathological lesions with different scores were detected. CONCLUSION: Our findings suggest that the inadequate virus shedding reduction and protection efficacy of studied vaccines were variable and that the type of vaccine to be used under field conditions should be reconsidered. Study of the variability between the Egyptian old emerged AI (AIV) 2017 H5N8 strains and the new emerging AIV 2018 H5N8 is required to achieve optimal protection and limit the current economic losses.

12.
Vet World ; 14(6): 1677-1681, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34316218

RESUMO

BACKGROUND AND AIM: Avian influenza (AI), which is one of the major respiratory diseases of poultry, and Escherichia coli (E. coli) have caused major economic losses around the world, including in Egypt. Therefore, in this study, we aimed to produce a vaccine from E. coli O157 and AI H5N1 formulated with Montanide ISA70 for the protection of poultry against both diseases. MATERIALS AND METHODS: We divided one hundred 3-week-old chicks into four groups: Group 1 was vaccinated with prepared inactivated AI H5N1formulated with Montanide ISA70, Group 2 was vaccinated with inactivated E. coli formulated with Montanide ISA70, Group 3 was vaccinated with combined E. coli and AI H5N1 formulated with Montanide ISA70, and Group 4 was an unvaccinated control group. We measured the immune response using the HI (hemagglutination inhibition) test, enzyme-linked immunosorbent assay (ELISA), and the challenge test. RESULTS: We found the three vaccines to be safe and sterile during all periods of examination and observation. The HI test showed that Group 1 exhibited specific antibody titers of 2.3 log2, 4.3 log2, 7.5 log2, 7.8 log2, 8 log2, and 8.1 log2 from week 2 to week 7, respectively, post-vaccination. Group 3 exhibited antibody titers of 3.3 log2, 5.8 log2, 7.8 log2, 8 log2, 8.3 log2, and 8.3 log2 from week 2 to week 7, respectively, post-vaccination. The immune response in both groups reached a high titer at week 6. The combined inactivated E. coli and AI H5N1 vaccine generated a higher immune response than the inactivated AI H5N1 vaccine, and a significant difference exists between the two groups. For Groups 2 and 3, the ELISA antibody titer exhibited its lowest value, 1996.5 and 2036.7, respectively, at week 1 post-vaccination; whereas, both groups exhibited the highest titers, 2227.7 (for Group 2) and 2287.3 (for Group 3), in week 3 post-booster. The ELISA for the combined inactivated E. coli and AI H5N1 vaccine had a higher titer than did the inactivated E. coli vaccine, and a significant difference exists between the two groups. Moreover, the protection rate was higher in Group 3, with 100% for E. coli and 90% for the AI H5N1 vaccine. CONCLUSION: Our findings demonstrate that producing a combined vaccine using E. coli and AI H5N1 formulated with Montanide ISA70 is recommended for protection against both diseases.

13.
Clin Implant Dent Relat Res ; 23(4): 555-561, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34105231

RESUMO

BACKGROUND: Ridge splitting technique is considered one of the successful horizontal bone augmentation procedures especially for the maxillary bone, the aim of this study was to compare marginal bone loss using a novel ridge splitting protocol versus the conventional technique. MATERIAL & METHODS: This was a randomized clinical trial including 20 patients who were randomly assigned to ridge splitting with simultaneous implant placement at the anterior maxillary aesthetic zone (10 patients, 29 dental implant) using patient specific guides (PSGs) or conventional technique (10 patients, 29 dental implant). In the control group free hand ridge splitting was done, while in the study group all the splitting and drilling procedures were done through specific slits and sleeves at the patient specific guides. Radiographic Assessment included measurements of linear changes in the vertical dimensions of the labial plate of bone on cross sectional cuts of computed tomography (CBCT) using mimics software. RESULTS: Wound healing was uneventful for all the patients except one patient in the control group that showed bad split and another showed buccal fenestration. The study group showed lower bone loss (1.38 ± 0.61 mm) compared to the control group (2.42 ± 0.63 mm), with statistical significance difference (P value = 0.001). The loss percentage also was higher in the study group (10.99 ± 4.76%) compared to the control group (19.12 ± 4.53%), and there was statistical significance difference between the two groups (P value = 0.001). CONCLUSION: Ridge splitting using PSGs appear to be efficient and promising than the free hand technique.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Transplante Ósseo , Computadores , Estudos Transversais , Implantação Dentária Endóssea , Estética Dentária , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia
14.
Sensors (Basel) ; 21(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670542

RESUMO

Several high-speed wireless systems use Orthogonal Frequency Division Multiplexing (OFDM) due to its advantages. 5G has adopted OFDM and is expected to be considered beyond 5G (B5G). Meanwhile, OFDM has a high Peak-to-Average Power Ratio (PAPR) problem. Hybridization between two PAPR reduction techniques gains the two techniques' advantages. Hybrid precoding-companding techniques are attractive as they require small computational complexity to achieve high PAPR reduction gain. Many precoding-companding techniques were introduced to increasing the PAPR reduction gain. However, reducing Bit Error Rate (BER) and out-of-band (OOB) radiation are more significant than increasing PAPR reduction gain. This paper proposes a new precoding-companding technique to better reduce the BER and OOB radiation than previous precoding-companding techniques. Results showed that the proposed technique outperforms all previous precoding-companding techniques in BER enhancement and OOB radiation reduction. The proposed technique reduces the Error Vector Magnitude (EVM) by 15 dB compared with 10 dB for the best previous technique. Additionally, the proposed technique increases high power amplifier efficiency (HPA) by 11.4%, while the best previous technique increased HPA efficiency by 9.8%. Moreover, our proposal achieves PAPR reduction gain better than the most known powerful PAPR reduction technique with a 99% reduction in required computational complexity.

15.
Oral Maxillofac Surg ; 25(2): 263-269, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33231752

RESUMO

PURPOSE: This study aims to compare the quality of free autogenous bone grafts harvested from two different mandibular donor sites, used as onlay shells to augment horizontally and vertically deficient anterior maxillary alveolar ridges. METHODS: Fourteen patients with edentulous and atrophic anterior maxillae are randomly allocated into two groups. Seven symphyseal chin (group I) and seven retromolar (group II) mandibular bone grafts were harvested and fashioned to construct buccal and palatal frameworks, fixed in place with mini-screws, followed by compacting the inter-positional gaps with an equal particulate mix of xenograft and autogenous cancellous particulates. Six months later, 42 core biopsies, three from each patient, 21 for each study group, were retrieved before the implants' insertion and subjected to histomorphometric bone area percent analysis. RESULTS: The bone area percent of the newly formed bone augmented with the chin shells was 52.53 ± 1.68% versus 47.97 ± 1.83% for the retromolar grafts. The mean area percent difference between both groups was statistically significant (p = 0.0004). CONCLUSION: A higher bone quality and more volumetric stability were associated with the symphyseal cortical shells. CLINICAL TRIAL REGISTRATION: The study was registered on www.clinicaltrials.gov (#: NCT03607006) in July 2018 by Ola Alaa El Morsy.


Assuntos
Aumento do Rebordo Alveolar , Processo Alveolar/cirurgia , Transplante Ósseo , Implantação Dentária Endóssea , Humanos , Mandíbula/cirurgia , Maxila/cirurgia
16.
Nucleic Acids Res ; 49(4): e19, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33095878

RESUMO

RNA structure formation in vivo happens co-transcriptionally while the transcript is being made. The corresponding co-transcriptional folding pathway typically involves transient RNA structure features that are not part of the final, functional RNA structure. These transient features can play important functional roles of their own and also influence the formation of the final RNA structure in vivo. We here present CoBold, a computational method for identifying different functional classes of transient RNA structure features that can either aid or hinder the formation of a known reference RNA structure. Our method takes as input either a single RNA or a corresponding multiple-sequence alignment as well as a known reference RNA secondary structure and identifies different classes of transient RNA structure features that could aid or prevent the formation of the given RNA structure. We make CoBold available via a web-server which includes dedicated data visualisation.


Assuntos
RNA/química , Análise de Sequência de RNA/métodos , Regiões 5' não Traduzidas , Biologia Computacional/métodos , Evolução Molecular , Conformação de Ácido Nucleico , Dobramento de RNA , RNA Catalítico/química , Riboswitch , Alinhamento de Sequência , Software , Transcrição Gênica
17.
Nucleic Acids Res ; 48(18): e105, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32976561

RESUMO

Interactions between biological entities are key to understanding their potential functional roles. Three fields of research have recently made particular progress: the investigation of transRNA-RNA and RNA-DNA transcriptome interactions and of trans DNA-DNA genome interactions. We now have both experimental and computational methods for examining these interactions in vivo and on a transcriptome- and genome-wide scale, respectively. Often, key insights can be gained by visually inspecting figures that manage to combine different sources of evidence and quantitative information. We here present R-chie, a web server and R package for visualizing cis and transRNA-RNA, RNA-DNA and DNA-DNA interactions. For this, we have completely revised and significantly extended an earlier version of R-chie (1) which was initially introduced for visualizing RNA secondary structure features. The new R-chie offers a range of unique features for visualizing cis and transRNA-RNA, RNA-DNA and DNA-DNA interactions. Particularly note-worthy features include the ability to incorporate evolutionary information, e.g. multiple-sequence alignments, to compare two alternative sets of information and to incorporate detailed, quantitative information. R-chie is readily available via a web server as well as a corresponding R package called R4RNA which can be used to run the software locally.


Assuntos
DNA/química , RNA/química , Software , Humanos , Internet , Conformação de Ácido Nucleico , Alinhamento de Sequência , Transcriptoma
18.
J Craniomaxillofac Surg ; 48(8): 719-723, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32713801

RESUMO

Reconstruction of mandibular discontinuity defects remains a challenge for maxillofacial surgeons. Despite vascularized free flaps representing the current gold standard for managing such defects, the search continues for other less morbid yet predictable interventions. This study aimed at reviving the idea of alloplastic mandibular endoprosthesis as a treatment modality for reconstruction of segmental mandibular defects following eradication of benign tumors. To reconstruct their segmental mandibular defects, this case series compiled seven patients who received patient-specific titanium implant (PSI) with osseointegrated components and were designed to receive a restoration for dental rehabilitation. The recruited patient population was followed-up for a period of 3-5 years. Three of the seven PSIs failed due to extensive intraoral mucosal dehiscence or persistent extraoral fistulae. Patients with the 4 surviving PSIs enjoyed good results in terms of occlusion, masticatory function, mouth opening as well as pleasing facial esthetics. The described technique represents a viable less morbid alternative to the standard bone grafting techniques for mandibular reconstruction in carefully selected patients. Further studies are needed to modify the PSI design and surface treatment for better outcomes.


Assuntos
Implantes Dentários , Neoplasias Mandibulares , Reconstrução Mandibular , Transplante Ósseo , Estética Dentária , Humanos , Mandíbula
19.
Oral Maxillofac Surg ; 24(4): 411-415, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32556619

RESUMO

PURPOSE: Various procedures have been adopted for eminence augmentation for treatment of recurrent temporomandibular joint dislocation. The aim of this study is to assess maximal incisal opening (MIO) using a custom-made titanium implant versus inlay autogenous augmentation from the patient's chin for more stable condylar movements. METHODS: Ten patients were treated in this study (20 joints) five patients with bilateral patient-specific titanium onlay implant and five for autogenous inlay grafting technique; each implant in the study group was virtually designed using a specific software and milled from titanium grade V blocks, then fixed with mini screws at the lateral aspect of the zygomatic arch while in the control group, autogenous corticocancellous bone block was harvested from the chin and wedged at the created defect of the eminence to increase its height. RESULTS: The follow-up period ranged from 6 months to 1 year to access the maximal incisal opening (MIO). The mean preoperative maximal incisal opening was 47.8 mm and that of the postoperative was 33.2 mm in the study group and 35.4 mm in the control group, respectively. One patient reported postoperative slight unilateral edema and pain that gradually diminishes after 1 month postoperative. CONCLUSION: No statistical difference between both groups p value 0.3.


Assuntos
Restaurações Intracoronárias , Titânio , Transplante Ósseo , Humanos , Articulação Temporomandibular , Zigoma
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