scholarly journals Structural characteristics of the bone surrounding dental implants placed into the tail-suspended mice

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yuto Otsu ◽  
Satoru Matsunaga ◽  
Takehiro Furukawa ◽  
Kei Kitamura ◽  
Masaaki Kasahara ◽  
...  

Abstract Background There are many unclear points regarding local structural characteristics of the bone surrounding the implant reflecting the mechanical environment. Purpose The purpose of this study is to quantitatively evaluate bone quality surrounding implants placed into the femurs of mice in an unloading model, and to determine the influence of the mechanical environment on bone quality. Methods Twenty 12-week-old male C57BL6/NcL mice (n = 5/group) were used as experimental animals. The mice were divided into two groups: the experimental group (n = 10) which were reared by tail suspension, and the control group (n = 10) which were reared normally. An implant was placed into the femur of a tail-suspended mouse, and after the healing period, they were sacrificed and the femur was removed. After micro-CT imaging, Villanueva osteochrome bone stain was performed. It was embedded in unsaturated polyester resin. The polymerized block was sliced passing through the center of the implant body. Next, 100-μm-thick polished specimens were prepared with water-resistant abrasive paper. In addition to histological observation, morphometric evaluation of cancellous bone was performed, and the anisotropy of collagen fibers and biological apatite (BAp) crystals was analyzed. Results As a result, the femoral cortical bone thickness and new peri-implant bone mass showed low values in the tail suspension group. The uniaxial preferential orientation of BAp c-axis in the femoral long axis direction in the non-implant groups, but biaxial preferential orientation of BAp c-axis along the long axis of implant and femoral long axis direction were confirmed in new bone reconstructed by implant placement. Collagen fiber running anisotropy and orientation of BAp c-axis in the bone surrounding the implant were not significantly different due to tail suspension. Conclusions From the above results, it was clarified that bone formation occurs surrounding the implant even under extremely low load conditions, and bone microstructure and bone quality adapted to the new mechanical environment are acquired.

Author(s):  
Elçin Bedeloğlu ◽  
Mustafa Yalçın ◽  
Cenker Zeki Koyuncuoğlu

The purpose of this non-random retrospective cohort study was to evaluate the impact of prophylactic antibiotic on early outcomes including postoperative pain, swelling, bleeding and cyanosis in patients undergoing dental implant placement before prosthetic loading. Seventy-five patients (45 males, 30 females) whose dental implant placement were completed, included to the study. Patients used prophylactic antibiotics were defined as the experimental group and those who did not, were defined as the control group. The experimental group received 2 g amoxicillin + clavulanic acid 1 h preoperatively and 1 g amoxicillin + clavulanic acid twice a day for 5 days postoperatively while the control group had received no prophylactic antibiotic therapy perioperatively. Data on pain, swelling, bleeding, cyanosis, flap dehiscence, suppuration and implant failure were analyzed on postoperative days 2, 7, and 14 and week 12. No statistically significant difference was detected between the two groups with regard to pain and swelling on postoperative days 2, 7, and 14 and week 12 ( p >0.05), while the severity of pain and swelling were greater on day 2 compared to day 7 and 14 and week 12 in both groups ( p =0.001 and p <0.05, respectively). Similarly, no significant difference was found between the two groups with regard to postoperative bleeding and cyanosis. Although flap dehiscence was more severe on day 7 in the experimental group, no significant difference was found between the two groups with regard to the percentage of flap dehiscence assessed at other time points. Within limitations of the study, it has been demonstrated that antibiotic use has no effect on implant failure rates in dental implant surgery with a limited number of implants. We conclude that perioperative antibiotic use may not be required in straightforward implant placement procedures. Further randomized control clinical studies with higher numbers of patients and implants are needed to substantiate our findings.


Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 932
Author(s):  
Arkadiusz Matuszewski ◽  
Monika Łukasiewicz ◽  
Jan Niemiec ◽  
Maciej Kamaszewski ◽  
Sławomir Jaworski ◽  
...  

The use of intensive selection procedure in modern broiler chicken lines has led to the development of several skeletal disorders in broiler chickens. Therefore, current research is focused on methods to improve the bone quality in birds. In ovo technology, using nanoparticles with a high specificity to bones, is a potential approach. The present study aimed to evaluate the effect of in ovo inoculation (IOI) of calcium carbonate nanoparticles (CCN) on chicken embryo development, health status, bone characteristics, and on broiler production results and bone quality. After assessing in vitro cell viability, the IOI procedure was performed with an injection of 500 μg/mL CCN. The control group was not inoculated with CCN. Hatchability, weight, and selected bone and serum parameters were measured in embryos. Part of hatchlings were reared under standard conditions until 42 days, and production results, meat quality, and bone quality of broilers were determined. CCN did not show cytotoxicity to cells and chicken embryo and positively influenced bone parameters of the embryos and of broilers later (calcification) without negatively affecting the production results. Thus, the IOI of CCN could modify the molecular responses at the stage of embryogenesis, resulting in better mineralization, and could provide a sustained effect, thereby improving bone quality in adult birds.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yi-Wen Cathy Tsai ◽  
Ren-Yeong Huang ◽  
Chia-Dan Cheng ◽  
Wan-Chien Cheng ◽  
David L. Cochran ◽  
...  

Abstract Background This study investigated the prevalence of labial bone perforation (LBP) related to the associated anatomic factors in anterior mandibular region using a virtual immediate implant placement procedure. Methods Series qualified CBCT images of 149 participants (894 teeth) were selected to analyze the assigned anatomical parameters, including concavity depth, concavity angle, torque, and deep bone thickness. Four classes of crestal and radicular dentoalveolar bone phenotypes (CRDAPs) of mandibular anterior teeth were categorized according to the thickness of dentoalveolar bone at both crestal and radicular zones. Data were adjusted for categorical (gender and CRDAP) and continuous (age, cavity angle, cavity depth, and deep bone thickness) variables using a multivariable logistic regression analysis with generalized estimating equation method. Results The overall probability of LBP after virtual implant placement was 21.6%. There is statistically significant higher prevalence of LBP at canine (28.5%) and CRDAP class II (29.2%) regions (p < 0.001). After adjusting confounding variables, CRDAP class II and class IV regions are more likely to have LBP when compared with CRDAP class I (control) regions (p < 0.01). The risk of LBP at canine site is 6.31 times more likely than at the central incisor (control) (p < 0.01). Conclusions Using a virtual immediate implant placement technique, the prevalence of LBP is significantly higher at the mandibular canine site and thin radicular dentoalveolar phenotype in the anterior mandibular region.


2021 ◽  
Vol 1 (3) ◽  
pp. 263502542199712
Author(s):  
Jordan D. Walters ◽  
Stephen F. Brockmeier

Background: This technique video reviews anatomic total shoulder arthroplasty (TSA) with a stemless humeral component using a representative case example. Indications: Stemless TSA is indicated for patients with symptomatic glenohumeral arthritis typically younger than 65 years of age. Stemless TSA may be used for other glenohumeral degenerative conditions such as avascular necrosis or posttraumatic arthropathy, provided acceptable humeral bone quality is confirmed intraoperatively using a thumb-press test. Poor bone quality is the primary contraindication. Technique Description: Preoperatively, computed tomography is typically used for planning, and intraoperative navigation through magnetic resonance imaging is also useful. The procedure’s critical elements include beach chair positioning, standard deltopectoral approach with lesser tuberosity osteotomy (LTO), freehand proximal humeral osteotomy, perpendicular proximal humeral exposure and subsequent preparation over a central guidewire, stemless implant and humeral head sizing, perpendicular glenoid exposure and implant placement, and final humeral implantation with LTO repair/fixation. A phased rehabilitation protocol includes 6-week sling immobilization to protect the subscapularis/LTO repair and return to normal activities between 3 and 6 months postoperatively. Discussion/Conclusion: Stemless TSA shows promising early and mid-term outcomes with complication rates, including humeral loosening rates, similar to standard stemmed components. Potential complications include neurovascular injury, infection, glenoid or humeral component loosening, and rotator cuff failure.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ádám László Nagy ◽  
Zsolt Tóth ◽  
Tamás Tarjányi ◽  
Nándor Tamás Práger ◽  
Zoltán Lajos Baráth

Abstract Background In this research the biomechanical properties of a bone model was examined. Porcine ribs are used as experimental model. The objective of this research was to investigate and compare the biomechanical properties of the bone model before and after implant placement. Methods The bone samples were divided in three groups, Group 1 where ALL-ON-FOUR protocol was used during pre-drilling and placing the implants, Group 2 where ALL-ON-FOUR protocol was used during pre-drilling, and implants were not placed, and Group 3 consisting of intact bones served as a control group. Static and dynamic loading was applied for examining the model samples. Kruskal–Wallis statistical test and as a post-hoc test Mann–Whitney U test was performed to analyze experimental results. Results According to the results of the static loading, there was no significant difference between the implanted and original ribs, however, the toughness values of the bones decreased largely on account of predrilling the bones. The analysis of dynamic fatigue measurements by Kruskal–Wallis test showed significant differences between the intact and predrilled bones. Conclusion The pre-drilled bone was much weaker in both static and dynamic tests than the natural or implanted specimens. According to the results of the dynamic tests and after a certain loading cycle the implanted samples behaved the same way as the control samples, which suggests that implantation have stabilized the skeletal bone structure.


Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1394
Author(s):  
Yong Sang Cho ◽  
So-Jung Gwak ◽  
Young-Sam Cho

In this study, we investigated the dual-pore kagome-structure design of a 3D-printed scaffold with enhanced in vitro cell response and compared the mechanical properties with 3D-printed scaffolds with conventional or offset patterns. The compressive modulus of the 3D-printed scaffold with the proposed design was found to resemble that of the 3D-printed scaffold with a conventional pattern at similar pore sizes despite higher porosity. Furthermore, the compressive modulus of the proposed scaffold surpassed that of the 3D-printed scaffold with conventional and offset patterns at similar porosities owing to the structural characteristics of the kagome structure. Regarding the in vitro cell response, cell adhesion, cell growth, and ALP concentration of the proposed scaffold for 14 days was superior to those of the control group scaffolds. Consequently, we found that the mechanical properties and in vitro cell response of the 3D-printed scaffold could be improved by kagome and dual-pore structures through DfAM. Moreover, we revealed that the dual-pore structure is effective for the in vitro cell response compared to the structures possessing conventional and offset patterns.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Ana Carolina Lupepsa ◽  
Paula Vargas-Sanchez ◽  
Marcella Goetz Moro ◽  
Leomar Emanuel Almeida Mecca ◽  
Marcela Claudino ◽  
...  

Abstract Background Several drugs are capable of promoting changes in bone metabolism. The aim of this study was to evaluate the effect of long-term low-dose aspirin (LDA) therapy on implant osseointegration. Methods Male Wistar rats were divided into 4 groups (n = 8/group) according to oral gavage solution received prior (42 days) to the implant surgery on the tibia. The control group was treated with saline solution for 7 (CG-7) and 28 (CG-28) days. The use of low-dose aspirin was performed in AG groups (6.75 mg/kg of aspirin) for 7 (AG-7) and 28 (AG-28) days. After experimental periods, histomorphometric evaluation of bone-to-implant contact (BIC) and the bone area between threads (BABT) was performed. Results Reduced BIC values were detected in AG-7 (62.8% ± 17.1) group compared to AG-28 (91.9% ± 5.4), CG-7 (82.7% ± 15.2), and CG-28 (89.9% ± 9.7). BABT evaluation revealed lower values in AG-7 (70.9% ± 15.2) compared to AG-28 (95.4% ± 3.7) and CG-28 (87.1% ± 10.2) groups. Conclusions The treatment with low doses of aspirin promoted a discrete inhibitory effect in the early stages (7 days) of repair after implant placement, specifically in the bone deposition. However, these effects were not detected in the late stages (28 days), considering BIC and BABT parameters.


2021 ◽  
pp. 29-30
Author(s):  
Deepika Sharma ◽  
Tarun Gaur ◽  
Karunakaran Keshav

With the advancement in the dental implant treatment, many new innovative improvements have been developed in the designs and components of implants. These improvements helps to handle the compromising situations where sometimes the good treatment option can become more challenging. One of the such grueling condition is implant placement in the anterior maxilla where dentist has to fulll both aesthetic and functional demand. Many aesthetic failures of implant have been reported in the literature in the anterior maxilla. One of them is placing implant in sites with deciency of facial bone thickness which sometimes resulted in malposition of implant. This case report discusses about the prosthodontic correction of malpositioned implant in the anterior maxilla by using castable abutment. The use of castable abutment is concluded as successful treatment option for complex misaligned and malposed single dental implant.


2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Corina Marilena Cristache

Despite numerous advantages over multislice computed tomography (MSCT), including a lower radiation dose to the patient, shorter acquisition times, affordable cost, and sometimes greater detail with isotropic voxels used in reconstruction, allowing precise measurements, cone beam computed tomography (CBCT) is still controversial regarding bone quality evaluation. This paper presents a brief review of the literature on accuracy and reliability of bone quality assessment with CBCT and a case report with step-by-step predictable treatment planning in esthetic zone, based on CBCT scans which enabled the clinician to evaluate, depending on bone volume and quality, whether immediate restoration with CAD-CAM manufactured temporary crown and flapless surgery may be a treatment option.


2020 ◽  
Vol 99 (4) ◽  
pp. 402-409 ◽  
Author(s):  
G. Avila-Ortiz ◽  
M. Gubler ◽  
M. Romero-Bustillos ◽  
C.L. Nicholas ◽  
M.B. Zimmerman ◽  
...  

Alveolar ridge preservation (ARP) therapy is indicated to attenuate the physiologic resorptive events that occur as a consequence of tooth extraction with the purpose of facilitating tooth replacement therapy. This randomized controlled trial was primarily aimed at testing the efficacy of ARP as compared with unassisted socket healing. A secondary objective was to evaluate the effect that local phenotypic factors play in the volumetric reduction of the alveolar bone. A total of 53 subjects completed the study. Subjects were randomized into either the control group, which involved only tooth extraction (EXT n = 27), or the experimental group, which received ARP using a combination of socket grafting with a particulate bone allograft and socket sealing with a nonabsorbable membrane (dPTFE) following tooth extraction (ARP n = 26). A set of clinical, linear, volumetric, implant-related, and patient-reported outcomes were assessed during a 14-wk healing period. All linear bone assessments (horizontal, midbuccal, and midlingual reduction) revealed that ARP is superior to EXT. Likewise, volumetric bone resorption was significantly higher in the control group (mean ± SD: EXT = −15.83% ± 4.48%, ARP = −8.36% ± 3.81%, P < 0.0001). Linear regression analyses revealed that baseline buccal bone thickness is a strong predictor of alveolar bone resorption in both groups. Interestingly, no significant differences in terms of soft tissue contour change were observed between groups. Additional bone augmentation to facilitate implant placement in a prosthetically acceptable position was deemed necessary in 48.1% of the EXT sites and only 11.5% of the ARP sites ( P < 0.004). Assessment of perceived postoperative discomfort at each follow-up visit revealed a progressive decrease over time, which was comparable between groups. Although some extent of alveolar ridge remodeling occurred in both groups, ARP therapy was superior to EXT as it was more efficacious in the maintenance of alveolar bone and reduced the estimated need for additional bone augmentation at the time of implant placement (ClinicalTrials.gov NCT01794806).


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