scholarly journals A Comparative Analysis of the Piezoelectric Ultrasonic Appliance and Trephine Bur for Apical Location: An In Vitro Study

2021 ◽  
Vol 11 (10) ◽  
pp. 1034
Author(s):  
Esther Cáceres Madroño ◽  
Paulina Rodríguez Torres ◽  
Soraya Oussama ◽  
Álvaro Zubizarreta-Macho ◽  
María Bufalá Pérez ◽  
...  
Keyword(s):  
Study Groups ◽  
Experimental Models ◽  
Site Preparation ◽  
T Test ◽  
Entry Point ◽  
Osteotomy Site ◽  
End Point ◽  
Planning Software ◽  
Preparation Techniques

To compare and contrast the accuracy of piezoelectric ultrasonic insert (PUI) and trephine bur (TB) osteotomy site preparation techniques for apical location. (1) Material and methods: A total of 138 osteotomy site preparations were randomly distributed into one of two study groups. Group A: TB technique (n = 69) and B: PUI technique (n = 69). A preoperative cone-beam computed tomography scan and an intraoral scan were performed and uploaded to implant-planning software to plan the virtual osteotomy site preparations for apical location. Subsequently, the osteotomy site preparations were performed in the experimental models with both osteotomy site preparation techniques and a postoperative CBCT scan was performed and uploaded into the implant-planning software and matched with the virtually planned osteotomy site preparations to measure the deviation angle and horizontal deviation as captured at the coronal entry point and apical end-point between osteotomy site preparations using Student’s t-test statistical analysis. (2) Results: The paired t-test found statistically significant differences at the coronal entry-point deviations (p = 0.0104) and apical end-point deviations (p = 0.0104) between the TB and PUI study groups; however, no statistically significant differences were found in the angular deviations (p = 0.309) between the trephine bur and piezoelectric ultrasonic insert study groups. (3) Conclusions: The results showed that the TB is more accurate than the PUI for apical location.

scholarly journals Accuracy of Computer-Aided Dynamic Navigation Compared to Computer-Aided Static Procedure for Endodontic Access Cavities: An In Vitro Study

2020 ◽  
Vol 9 (1) ◽  
pp. 129 ◽  
Author(s):  
Álvaro Zubizarreta-Macho ◽  
Ana de Pedro Muñoz ◽  
Elena Riad Deglow ◽  
Rubén Agustín-Panadero ◽  
Jesús Mena Álvarez
Keyword(s):  
Navigation System ◽  
In Vitro Study ◽  
Study Groups ◽  
T Test ◽  
Anterior Teeth ◽  
Planning Software ◽  
Computer Aided ◽  
Dynamic Navigation ◽  
Group B

Purpose: To analyze the accuracy of two computer-aided navigation techniques to guide the performance of endodontic access cavities compared with the conventional access procedure. Materials and Methods: A total of 30 single-rooted anterior teeth were selected, which were randomly distributed into three study groups: Group A—guided performance of endodontic access cavities through computer-aided static navigation system (n = 10) (SN); Group B—guided performance of endodontic access cavities through computer-aided dynamic navigation system (n = 10) (DN); and Group C—manual (freehand) performance of endodontic access cavities (n = 10) (MN). The endodontic access cavities of the SN group were performed with a stereolithography template designed on 3D implant planning software, based on preoperative cone-beam computed tomography (CBCT) and a 3D extraoral surface scan, and endodontic access cavities of the DN group were planned and performed by the dynamic navigation system. After endodontic access cavities were performed, a second CBCT was done, and the degree of accuracy between the planned and performed endodontic access cavities was analyzed using therapeutic planning software and Student’s t-test. Results: Paired t-test revealed no statistically significant differences between SN and DN at the coronal (p = 0.6542), apical (p = 0.9144), or angular (p = 0.0724) level; however, statistically significant differences were observed between the two computer-aided navigation techniques and the MN group at the coronal (p < 0.0001), apical (p < 0.0001), and angular (p < 0.0001) level. Conclusion: Both computer-aided static and dynamic navigation procedures allowed accurate performance of endodontic access cavities.

scholarly journals Influence of the Digital Mock-Up and Experience on the Ability to Determine the Prosthetically Correct Dental Implant Position during Digital Planning: An In Vitro Study

2019 ◽  
Vol 9 (1) ◽  
pp. 48
Author(s):  
Miriam O’Connor Esteban ◽  
Elena Riad Deglow ◽  
Álvaro Zubizarreta-Macho ◽  
Sofía Hernández Montero
Keyword(s):  
Dental Implants ◽  
Dental Implant ◽  
In Vitro Study ◽  
Study Groups ◽  
T Test ◽  
Dental Surgery ◽  
Operator Experience ◽  
Planning Software ◽  
Before And After

The purpose of this study was to analyze the influence of the digital mock-up and operator experience on the dental implant planning position. A total of 200 dental implants were planned, which were distributed into two study groups: A. dental implant planning by dental surgeons with 5–10 years of experience (n = 80); and B. dental implant planning by dental surgery students without experience (n = 120). Operators were required to plan eight dental implants in the same maxillary edentulous case uploaded in 3D implant-planning software, before and after using the digital mock-up. Deviations between the dental implant planning positions before and after using the digital mock-up were analyzed at platform, apical and angular levels, and were analyzed using a 3D implant-planning software using Student’s t test. The paired t-test revealed statistically significant differences between the deviation levels of participants with 5–10 years’ experience and no experience at the platform, apical and angular levels. Digital mock-ups allow for more accurate dental implant planning regardless of the experience of the operator. Nevertheless, they are more useful for operators without dental surgery experience.

scholarly journals Influence of Drilling Technique on the Radiographic, Thermographic, and Geomorphometric Effects of Dental Implant Drills and Osteotomy Site Preparations

2020 ◽  
Vol 9 (11) ◽  
pp. 3631
Author(s):  
Lara Fraguas de San José ◽  
Filippo Maria Ruggeri ◽  
Roberta Rucco ◽  
Álvaro Zubizarreta-Macho ◽  
Jorge Alonso Pérez-Barquero ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Dental Implant ◽  
High Speed ◽  
Digital Camera ◽  
Study Groups ◽  
Site Preparation ◽  
Osteotomy Site ◽  
Study Group ◽  
Micro Computed Tomography ◽  
Drilling Technique

The aim of this comparative study is to analyze the influence of drilling technique on the radiographic, thermographic, and geomorphometric effects of dental implant drills and osteotomy site preparations. One hundred and twenty osteotomy site preparations were performed on sixty epoxy resin samples using three unused dental implant drill systems and four drilling techniques performed with a random distribution into the following study groups: Group A: drilling technique performed at 800 rpm with irrigation (n = 30); Group B: drilling technique performed at 45 rpm without irrigation (n = 30); Group C: drilling technique performed at 45 rpm with irrigation (n = 30); and Group D: drilling technique performed at 800 rpm without irrigation (n = 30). The osteotomy site preparation morphologies performed by the 4.1 mm diameter dental implant drills from each study group were analyzed and compared using a cone beam computed tomography (CBCT) scan. The termographic effects generated by the 4.1 mm diameter dental implant drills from each study group were registered using a termographic digital camera and the unused and 4.1 mm diameter dental implant drills that were used 30 times from each study group were exposed to a micro computed tomography (micro-CT) analysis to obtain a Standard Tessellation Language (STL) digital files that determined the wear comparison by geomorphometry. Statistically significant differences were observed between the thermographic and radiographic results of the study groups (p < 0.001). The effect of cooling significatively reduced the heat generation during osteotomy site preparation during high-speed drilling; furthermore, osteotomy site preparation was not affected by the wear of the dental implant drills after 30 uses, regardless of the drilling technique.

scholarly journals Influence of the Computer-Aided Static Navigation Technique and Mixed Reality Technology on the Accuracy of the Orthodontic Micro-Screws Placement. An In Vitro Study

2021 ◽  
Vol 11 (10) ◽  
pp. 964
Author(s):  
Elena Riad Deglow ◽  
Sergio Toledano Gil ◽  
Álvaro Zubizarreta-Macho ◽  
María Bufalá Pérez ◽  
Paulina Rodríguez Torres ◽  
...  
Keyword(s):  
Mixed Reality ◽  
Intraoperative Complications ◽  
In Vitro Study ◽  
Study Groups ◽  
Entry Point ◽  
Screw Placement ◽  
Freehand Technique ◽  
Computer Aided ◽  
Mr Study

To analyze the effect of a computer-aided static navigation technique and mixed reality technology on the accuracy of orthodontic micro-screw placement. Material and methods: Two hundred and seven orthodontic micro-screws were placed using either a computer-aided static navigation technique (NAV), a mixed reality device (MR), or a conventional freehand technique (FHT). Accuracy across different dental sectors was also analyzed. CBCT and intraoral scans were taken both prior to and following orthodontic micro-screw placement. The deviation angle and horizontal deviation were then analyzed; these measurements were taken at the coronal entry point and apical endpoint between the planned and performed orthodontic micro-screws. In addition, any complications resulting from micro-screw placement, such as spot perforations, were also analyzed across all dental sectors. Results: The statistical analysis showed significant differences between study groups with regard to the coronal entry-point (p < 0.001). The NAV study group showed statistically significant differences from the FHT (p < 0.001) and MR study groups (p < 0.001) at the apical end-point (p < 0.001), and the FHT group found significant differences from the angular deviations of the NAV (p < 0.001) and MR study groups deviations (p = 0.0011). Different dental sectors also differed significantly. (p < 0.001) Additionally, twelve root perforations were observed in the FHT group, while there were no root perforations in the NAV group. Conclusions: Computer-aided static navigation technique enable more accurate orthodontic micro-screw placement and fewer intraoperative complications when compared with the mixed reality technology and conventional freehand techniques.

scholarly journals Influence of the Computer-Aided Static Navigation Technique on the Accuracy of the Orthodontic Micro-Screws Placement: An In Vitro Study

2021 ◽  
Vol 10 (18) ◽  
pp. 4127
Author(s):  
Paulina Rodríguez Torres ◽  
Sergio Toledano Gil ◽  
Álvaro Zubizarreta-Macho ◽  
María Bufalá Pérez ◽  
Elena Riad Deglow ◽  
...  
Keyword(s):  
Intraoperative Complications ◽  
In Vitro Study ◽  
Study Groups ◽  
Entry Point ◽  
Screw Placement ◽  
Study Group ◽  
Freehand Technique ◽  
Computer Aided ◽  
Group A

To analyze the influence of the computer-aided static navigation technique on the accuracy of placement of orthodontic micro-screws. One hundred and thirty-eight orthodontic micro-screws were randomly assigned to the following study groups: Group A. orthodontic micro-screw placement using a computer-aided static navigation technique (n = 69); B. orthodontic micro-screw placement using the conventional freehand technique (n = 69). In addition, the accuracy in the canine–premolar, premolar and molar sectors was analyzed in each study group. Cone-beam computed tomography and intraoral scans were taken both prior and subsequent to orthodontic micro-screw placement. The images were then uploaded using a 3D implant planning software, where the deviation and horizontal angles were analyzed using a multivariate linear model. These measurements were taken at the coronal entry point and apical endpoint between the planned orthodontic micro-screws. In addition, any complications resulting from micro-screw placement, such as spot perforations, were also analyzed in all dental sectors. The statistical analysis showed significant differences between the two study groups with regard to the coronal entry-point, apical end-point (p < 0.001) and angular deviations (p < 0.001) between the computer-aided static navigation technique and freehand technique study groups. Moreover, statistically significant differences were showed between the different dental sectors (p < 0.001). Additionally, twelve root perforations were observed at the conventional free hand technique study group while there were no root perforations in the computer-aided static navigation technique study group. The results showed that the computer-aided static navigation technique enables a more accurate orthodontic micro-screw placement with less intraoperative complications when compared with the conventional freehand technique.

scholarly journals Peri-Implant Bone Damage Procured by Piezoelectric and Conventional Implant Site Preparation: An In Vitro Comparison

2020 ◽  
Vol 10 (24) ◽  
pp. 8909
Author(s):  
Alberto Rebaudi ◽  
Federico Rebaudi ◽  
Fabrizio Barberis ◽  
Gilberto Sammartino ◽  
Gaetano Marenzi
Keyword(s):  
Cortical Bone ◽  
Cancellous Bone ◽  
Site Preparation ◽  
Bone Surface ◽  
Bone Trauma ◽  
Bone Damage ◽  
Fresh Bone ◽  
Implant Site Preparation ◽  
Preparation Techniques

Background: The conventional drill technique is the most commonly used for the implant site preparation of the desired diameter and length. Ultrasonic implant site preparation (UISP) can also be used to perform an implant site preparation of the desired dimensions. Methods: Implant sites were prepared in fresh bone ribs with two different implant site preparation techniques: implant surgical drills and piezoelectric tips. Samples were analyzed with scanning electron microscopy (SEM) for evaluating the peri-implant bone damage. Result: In the surgical drills group, the cortical bone surface showed several cracks and the bone vascular canals were hidden by a dense smear layer. Cancellous bone showed large irregularities and trabecular fractures. The piezoelectric group showed a clean and smooth cortical bone surface with opened bone vascular canals; the cancellous bone presented a regular morphology, and the trabecular spaces, clearly visible, were free of debris. Conclusions: Ultrasonic implant site preparation showed cleaner bone surfaces and lower bone trauma compared with the preparation using implant surgical drills.

scholarly journals Novel Digital Technique to Analyze the Influence of the Operator Experience on the Accuracy of the Orthodontic Micro-Screws Placement

2021 ◽  
Vol 11 (1) ◽  
pp. 400
Author(s):  
María Bufalá Pérez ◽  
Miriam O’Connor Esteban ◽  
Álvaro Zubizarreta-Macho ◽  
Elena Riad Deglow ◽  
Sofía Hernández Montero ◽  
...  
Keyword(s):  
Intraoperative Complications ◽  
Study Groups ◽  
T Test ◽  
Entry Point ◽  
Study Group ◽  
Years Of Experience ◽  
Digital Technique ◽  
Operator Experience ◽  
Before And After ◽  
Paired T Test

To analyze the influence of the operator experience on the accuracy of orthodontic self-tapping micro-screws placement, a total of 60 orthodontic self-tapping micro-screws were randomly distributed into two study groups: Group A. Orthodontic micro-screws placement by an orthodontist with 10 years of experience (n = 30); and B. Orthodontic micro-screws placement by an orthodontist student without experience (n = 30). Cone-beam computed tomography scans and intraoral scans were performed before and after the orthodontic self-tapping micro-screws placement and uploaded in 3D implant-planning software to analyze the deviation angle and the horizontal deviation measured at the coronal entry point and apical endpoint between orthodontic micro-screws planned and performed. In addition, intraoperative complications such as root perforations after orthodontic self-tapping micro-screws placement and fracture of the orthodontic self-tapping micro-screws during their placement were also analyzed. The paired t-test revealed statistically significant differences at the apical endpoint (p = 0.004) of planned and performed orthodontic self-tapping micro-screws between the orthodontist with 10 years of experience and the orthodontist student without experience. However, the paired t-test revealed no statistically significant differences at the coronal entry point (p = 0.220) and angular deviations (p = 0.602) of planned and performed orthodontic self-tapping micro-screws between the orthodontist with 10 years of experience and the orthodontic student without experience. Furthermore, five root perforations were observed in the no experience study group and three orthodontic self-tapping micro-screws were fractured in each study group. In conclusion, the results show that the greater experience of the operator influences the accuracy of orthodontic micro-screws placement, resulting in less intraoperative complications.

SEM Evaluation of Fluoride Pretreatment Effects on Acid-Etching of Caries-Like Enamel Lesions In Vitro

1981 ◽  
Vol 39 ◽  
pp. 474-475
Author(s):  
M. John Hicks
Keyword(s):  
Dental Enamel ◽  
Preventive Measure ◽  
Acid Etching ◽  
Distilled Water ◽  
Adhesive Resin ◽  
Fluoride Treatment ◽  
Treatment Groups ◽  
Pretreatment Effects ◽  
Preparation Techniques

Acid-etching of enamel surfaces has been performed routinely to bond adhesive resin materials to sound dental enamel as a caries-preventive measure. The effect of fluoride pretreatment on acid-etching of enamel has been reported to produce inconsistent and unsatisfactory etching patterns. The failure to obtain an adequate etch has been postulated to be due to fluoride precipitation products deposited on the enamel surface. The purpose of this study was to evaluate the effects of fluoride pretreatment on acid-etching of carieslike lesions of human dental enamel.Caries-like lesions of enamel were created in vitro on human molar and premolar teeth. The teeth were divided into two fluoride treatment groups. The specimens were exposed for 4 minutes to either a 2% Sodium Fluoride (NaF) solution or a 10% Stannous Fluoride (SnF2) solution. The specimens were then washed in deionized-distilled water. Each tooth was sectioned into four test regions. This was carried out to compare the effects of various time exposures (0 to 2 minutes) and differing concentrations (10 to 60% w/w) of phosphoric acid (H3PO4) on etching of caries-like lesions. Standard preparation techniques for SEM were performed on the specimens.

Neutralization of a Low Molecular Weight Heparin (LHN-1) and Conventional Heparin by Protamine Sulfate in Rats

1986 ◽  
Vol 56 (03) ◽  
pp. 318-322 ◽  
Author(s):  
V Diness ◽  
P B Østergaard
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight Heparin ◽  
Thrombus Formation ◽  
Experimental Models ◽  
Protamine Sulfate ◽  
Low Molecular Weight ◽  
Antithrombotic Effect ◽  
Higher Doses

SummaryThe neutralization of a low molecular weight heparin (LHN-1) and conventional heparin (CH) by protamine sulfate has been studied in vitro and in vivo. In vitro, the APTT activity of CH was completely neutralized in parallel with the anti-Xa activity. The APTT activity of LHN-1 was almost completely neutralized in a way similar to the APTT activity of CH, whereas the anti-Xa activity of LHN-1 was only partially neutralized.In vivo, CH 3 mg/kg and LHN-1 7.2 mg/kg was given intravenously in rats. The APTT and anti-Xa activities, after neutralization by protamine sulfate in vivo, were similar to the results in vitro. In CH treated rats no haemorrhagic effect in the rat tail bleeding test and no antithrombotic effect in the rat stasis model was found at a protamine sulfate to heparin ratio of about 1, which neutralized APTT and anti-Xa activities. In LHN-1 treated rats the haemorrhagic effect was neutralized when APTT was close to normal whereas higher doses of protamine sulfate were required for neutralization of the antithrombotic effect. This probably reflects the fact that in most experimental models higher doses of heparin are needed to induce bleeding than to prevent thrombus formation. Our results demonstrate that even if complete neutralization of APTT and anti-Xa activities were not seen in LHN-1 treated rats, the in vivo effects of LHN-1 could be neutralized as efficiently as those of conventional heparin. The large fall in blood pressure caused by high doses of protamine sulfate alone was prevented by the prior injection of LHN-1.

Antimicrobial peptides for the treatment of pulmonary tuberculosis, allies or foes?

2018 ◽  
Vol 24 (10) ◽  
pp. 1138-1147
Author(s):  
Bruno Rivas-Santiago ◽  
Flor Torres-Juarez
Keyword(s):  
Pulmonary Tuberculosis ◽  
Antimicrobial Peptides ◽  
Experimental Models ◽  
New Drugs ◽  
World Health ◽  
Public Health Issue ◽  
Health Organization ◽  
Drug Resistant Strains

Tuberculosis is an ancient disease that has become a serious public health issue in recent years, although increasing incidence has been controlled, deaths caused by Mycobacterium tuberculosis have been accentuated due to the emerging of multi-drug resistant strains and the comorbidity with diabetes mellitus and HIV. This situation is threatening the goals of World Health Organization (WHO) to eradicate tuberculosis in 2035. WHO has called for the creation of new drugs as an alternative for the treatment of pulmonary tuberculosis, among the plausible molecules that can be used are the Antimicrobial Peptides (AMPs). These peptides have demonstrated remarkable efficacy to kill mycobacteria in vitro and in vivo in experimental models, nevertheless, these peptides not only have antimicrobial activity but also have a wide variety of functions such as angiogenesis, wound healing, immunomodulation and other well-described roles into the human physiology. Therapeutic strategies for tuberculosis using AMPs must be well thought prior to their clinical use; evaluating comorbidities, family history and risk factors to other diseases, since the wide function of AMPs, they could lead to collateral undesirable effects.

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