scholarly journals Stability of Mini-Screws Invading the Dental Roots and Their Impact on the Paradental Tissues in Beagles

2009 ◽  
Vol 79 (2) ◽  
pp. 248-255 ◽  
Author(s):  
Yoon-Goo Kang ◽  
Ji-Young Kim ◽  
Young-Jun Lee ◽  
Kyu-Rhim Chung ◽  
Young-Guk Park

Abstract Objective: To examine the stability of mini-screws that invade a dental root by measuring the retention period/failure rate, and to illustrate their effects on paradental tissues. Materials and Methods: Three adult male beagle dogs received 48 orthodontic mini-screws. Half of the mini-screws were implanted to invade the roots, and the rest were placed in the middle of the alveolar bone. Half of the mini-screws were loaded immediately. The retention period of the mini-screws was documented. The dogs were euthanized after 8 weeks, and tissue samples were examined histologically. Results: The failure rate of the mini-screws that invaded the roots was 79.2%, and that of the mini-screws in the middle of the alveolar bone was 8.3%. The application of force had little effect on the failed mini-screws. Moderately injured roots were repaired with osteoid and/or cementoid tissues with normal periodontal ligaments, followed by recovery of the original configuration. Conclusion: Orthodontic mini-screws had a higher failure rate when placed to invade the dental roots. However, minimally damaged dental roots do not adversely affect the healing process. (Angle Orthod. 2009:79; )

Author(s):  
Brian J Smith ◽  
Stephen M Kirschner ◽  
Lon V Kendall

In cynomolgus macaques, plasma levels of sustained-release formulations of meloxicam meet or exceed efficacious concentrations for 48 to 72 h, thereby allowing less animal handling and providing more consistent efficacy than standard formulations of meloxicam. The goal of this study was to compare the pharmacokinetics of a single subcutaneous dose of a sustained-release formulation of meloxicam (Melox-SR) with those of oral (Melox-PO) and standard subcutaneous (Melox-SC) formulations dosed every 24 h for 3 consecutive days. Dogs (5 or 6 adult male Beagles) each received the following 3 treat- ments: first, Melox-SR (10 mg/mL, 0.6 mg/kg SC once), next Melox-SC (0.2 mg/kg SC once, followed by 0.1 mg/kg SC every 24 h), and finally Melox-PO (same dosage as Melox-SC), with a washout period of at least 2 wk between formulations. Blood was collected at 0 (baseline), 1, 4, 8, 12, 24, 48, and 72 h after the initial administration of each formulation for comparison of meloxicam plasma concentrations. Blood was also collected before administration and at 48 h after Melox-SR injection for CBC and chemistry analysis. Plasma concentrations (mean ± 1 SD) of Melox-SR peaked at the 1-h time point (2180 ± 359 ng/ mL), whereas those of Melox-PO (295 ± 55 ng/mL) and Melox-SC (551 ± 112 ng/mL) peaked at the 4-h time point. Melox-SR yielded significantly higher plasma concentrations than Melox-PO and Melox-SC until the 48 and 72-h time points, respec- tively. Melox-SC plasma concentrations were significantly higher than those of Melox-PO at 4, 8, 12, 24, 48 and 72 h. No lesions were noted at the Melox-SR injection sites, and Melox-SR administration was not associated with changes in the CBC and serum chemistry panels. A single 0.6-mg/kg dose of Melox-SR can yield plasma concentrations that exceed 350 ng/mL for at least 72 h in adult male dogs.


2021 ◽  
Vol 11 (Suppl. 1) ◽  
pp. 299-302
Author(s):  
Utku Nezih Yılmaz ◽  
Fatma Eriş Derkuş

Aim: Today, dental implant applications have become the most preferred option in the treatment of tooth deficiencies. Long-term successful results in dental implant applications depend largely on the volume and quality of the hard and soft tissues in the relevant region. Insufficient soft tissues and alveolar crest resorption complicate implant applications. Grafts and additional surgical procedures are required to compensate for resorption and to provide bone augmentation. Shell technique, one of the augmentation methods used in the treatment of alveolar bone defects, is an important procedure for guided bone regeneration. The purpose of this case report is to describe the treatment of vertical and horizontal bone loss with the Shell technique using allogeneic cortical grafts. Methodology: A 58-year-old female patient without any systemic disease was admitted to our clinic with the complaint of tooth loss in the right posterior mandibular region. In the intraoral and radiological examinations, it was determined that the bone volume in the relevant region was not sufficient for dental implant. Two-stage surgical treatment was planned for the patient. First, vertical and horizontal bone defects were augmented with allogeneic cortical graft application under local anesthesia. After the healing process, dental implants were placed in the sufficient volume of the alveolar bone and the patient's treatment was completed. Conclusion: Allogeneic grafts in the treatment of alveolar crest defects; it is a good alternative to autogenous bone grafts,there is no need for a second surgical field and the resulting reduction in morbidity.   How to cite this article: Eriş Derkuş F, Yılmaz UN. Current approach to bone augmentation with allogeneic cortical graft: A case report. Int Dent Res 2021;11(Suppl.1):299-302. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.44     Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.


2019 ◽  
Author(s):  
Alexander P Young ◽  
Carmen F Landry ◽  
Daniel J Jackson ◽  
Russell C Wyeth

Reverse transcription quantitative PCR (RT-qPCR) is a robust technique for the quantification and comparison of gene expression across multiple tissues. To obtain reliable results, one or more reference genes must be employed to normalize expression measurements among treatments or tissue samples. Candidate reference genes must be validated to ensure that they are stable prior to use in qPCR experiments. The pond snail (Lymnaea stagnalis) is a common research organism, particularly in the areas of learning and memory, and is an emerging target for qPCR experimentation. However, no systematic assessment of reference genes has been performed in this animal. Therefore, the aim of our research was to identify stable reference genes to normalize gene expression data from a variety of tissues in L. stagnalis. We evaluated a panel of seven reference genes across six different tissues in L. stagnalis with RT-qPCR. The genes included: elongation factor 1-alpha (EF1α), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), beta-actin (ACTB), beta-tubulin (TUBB), ubiquitin (UBI), prenylated rab acceptor protein 1 (Rapac1), and a voltage gated potassium channel (VGKC). These genes exhibited a wide range of expression levels among tissues. The stability of each of the genes was consistent when measured by any of the standard stability assessment algorithms: geNorm, NormFinder, BestKeeper and RefFinder. Our data indicate that GAPDH and EF1α are highly stable in the tissues that we examined (central nervous system, tentacles, lips, penis, foot, mantle) as well as in pooled analyses. We do not recommend VGKC for use in RT-qPCR experiments due to its relatively low expression stability. Our results were generally congruent with those obtained from similar studies in other molluscs. Given that a minimum of two reference genes are recommended for data normalization, we suggest GAPDH and EF1α are a strong option for multi-tissue analyses of RT-qPCR data in Lymnaea stagnalis.


2021 ◽  
Vol 1 (2) ◽  
Author(s):  
Andyka Yasa I Putu Gede ◽  
I Made Jawi ◽  
I Made Muliarta

Tooth extraction is a dental treatment that is performed frequently in dentistry. This procedure will stimulate a sophisticated healing process involving a variety of biological factors although it takes a long time to complete. Three phases occur in this process i.e. the inflammatory phase, the proliferation phase, and the remodeling phase which aim to restore the tissue function. Several interventions can be used to accelerate bone formation after tooth extraction. Recently, hyaluronic acid (HA) has been commonly used in dentistry due to their essential physiological effects for the periodontal connective tissue, gingiva, and alveolar bone. Hyaluronic acidis a natural non-sulfate glycosaminoglycans compound that has high molecular weight consisting of D-glucuronic acid and N-acetylglucosamine. Hyaluronic acidis also a component of the extracellular matrix that plays an important role in morphogenesis and tissue healing. The mechanism of action of HA works in two ways, that is passive and active mechanism. The passive mechanism is depend on physical and chemical properties of HA that can change the molecular weight and concentration properties. The active mechanism of HA works by stimulating signal transduction pathway initiated by ligand binding with its receptors through autocrine or paracrine processes. The administration of HA can accelerate bone formation due to it can enhance bone morphogenetic protein (BMP) which belongs to the TGF- β superfamily that has high osteogenic capacity. The HA works through a passive mechanism that depends on its molecular weight and an active mechanism by increasing BMP activity.


2015 ◽  
Vol 9 (1) ◽  
pp. 52-59 ◽  
Author(s):  
Akihito Kato ◽  
Hirofumi Miyaji ◽  
Ryosuke Ishizuka ◽  
Keisuke Tokunaga ◽  
Kana Inoue ◽  
...  

Objective : Biomodification of the root surface plays a major role in periodontal wound healing. Root surface modification with bone morphogenetic protein (BMP) stimulates bone and cementum-like tissue formation; however, severe ankylosis is simultaneously observed. Bio-safe collagen hydrogel scaffolds may therefore be useful for supplying periodontal ligament cells and preventing ankylosis. We examined the effects of BMP modification in conjunction with collagen hydrogel scaffold implantation on periodontal wound healing in dogs. Material and Methods: The collagen hydrogel scaffold was composed of type I collagen sponge and collagen hydrogel. One-wall infrabony defects (5 mm in depth, 3 mm in width) were surgically created in six beagle dogs. In the BMP/Col group, BMP-2 was applied to the root surface (loading dose; 1 µg/µl), and the defects were filled with collagen hydrogel scaffold. In the BMP or Col group, BMP-2 coating or scaffold implantation was performed. Histometric parameters were evaluated at 4 weeks after surgery. Results: Single use of BMP stimulated formation of alveolar bone and ankylosis. In contrast, the BMP/Col group frequently enhanced reconstruction of periodontal attachment including cementum-like tissue, periodontal ligament and alveolar bone. The amount of new periodontal ligament in the BMP/Col group was significantly greater when compared to all other groups. In addition, ankylosis was rarely observed in the BMP/Col group. Conclusion: The combination method using root surface modification with BMP and collagen hydrogel scaffold implantation facilitated the reestablishment of periodontal attachment. BMP-related ankylosis was suppressed by implantation of collagen hydrogel.


2019 ◽  
Vol 14 (1) ◽  
pp. 311-317
Author(s):  
Wei Liu ◽  
Ben Chen ◽  
Youyang Zheng ◽  
Yuehua Shi ◽  
Zhuojin Shi

AbstractPlatelet-rich plasma (PRP) has been shown to be a beneficial growth factor for bone tissue healing and is used in implantology. The aim of this study was to investigate the effects of PRP on bone defects in rabbits. Twenty rabbits were used to establish the implant bone defect model in this study. An intrabony defect (5mm × 5mm × 3mm) was created in alveolar bone in the lower jar of each rabbit. The wound was treated with PRP. The expression of platelet-derived growth factor BB (PDGFBB) was assessed by enzyme-linked immunosorbent assay (ELISA). Focal adhesion kinase (FAK) and related phosphatidylinositol 3-kinase (PI3K)/AKT (protein kinase B) levels were measured by Western blot. The results show that PRP could significantly improve the bone healing process when compared with control, and 10% PRP could markedly increase fibroblast proliferation 48-h post treatment. PDGFBB was higher in the PRP group than that in the control group. PRP treatment also could elevate the phosphorylation of FAK and PI3K/AKT, although the inhibitor of PDGFR could reverse this trend. These results suggest that PRP treatment improves the bone healing process through the FAK/PI3K/AKT pathway.


2012 ◽  
Vol 87 (6) ◽  
pp. 851-855
Author(s):  
Patrícia Luciana Batista Domingos ◽  
Agostinho Gonçalves Viana ◽  
Carlos Alberto de Carvalho Fraga ◽  
Paulo Rogério Ferreti Bonan

BACKGROUND: Leishmaniases are zoonoses considered a public health problem, representing a complex group of diseases with a broad clinical spectrum and epidemiological diversity. Leishmaniasis is caused by several species of protozoa of the genus Leishmania. The evolution of the pathology and the resolution of the leishmaniasis are dependent mainly on the Leishmania species involved, although the cytokine profile plays an important role in the development of the immune response. OBJECTIVES: The purpose of our study was to evaluate the immune response of patients affected by lesions of cutaneous leishmaniasis by immunostaining of the OX40, CD20, IFN-γ and IL-4 proteins. METHODS: The tissue samples were collected from indolent skin ulcers confirmed as cutaneous leishmaniasis of 41 patients aged between six and 90 years. The lesions were submitted to OX40, CD20, INF-γ and IL-4 immunolabeling. RESULTS: We observed a statistically significant higher expression of IFN-γ compared with IL-4 (p=0.009). Besides, OX40 had higher expression when compared with CD20 (p<0.001). CONCLUSION: The present study indicates that the immune response in lesions of cutaneous leishmaniasis is associated with a healing process, which can be explained by the higher expression of IFN-γ when compared with IL4 protein levels.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Ahmad Jabir Rahyussalim ◽  
Aldo Fransiskus Marsetio ◽  
Ifran Saleh ◽  
Tri Kurniawati ◽  
Yudan Whulanza

Today, orthopaedics is still in search for the most reliable biomaterial for prosthesis. The biomaterial needs to have good longevity and other supporting properties in order to maintain low implant failure. An ideal metallic biomaterial should be biocompatible, has similar elastic modulus to that of bone, has excellent resistance to fatigue, corrosion, aseptic loosening, and wear, and has good bone-bonding ability. The success of an implant depends on many factors. Good osseointegration is one of the factors required to reduce the rate of loosening of implants and in order to increase the chance of osseointegration, high stability of implants and early healing process encouragement are needed.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4110-4110
Author(s):  
Maria Elvira P. Correa ◽  
Oslei P. Almeida ◽  
Danyel Peres ◽  
Marcelo C. Alves ◽  
Fernando F. Costa ◽  
...  

Abstract The beneficial aspects of fibrin sealants for soft tissues are well documented, but studies of their direct influence on bone healing and their effectiveness in augmenting bone graft healing have produced conflicting results. The aim of this study was to evaluate the influence of fibrin sealants (FS) in the alveolar bone healing process during a period of up to 28 days. Seventy-five Wistar rats were submitted to a superior incisor extraction after intramuscular anesthesia (kentamine chloridrate 10% – 10mg/kg and tiazina chloridrate-5mg/kg). The rats were divided into tree different groups and the sealants were introduced into the alveolar bone. The first group (25) received human homemade fibrin glue, the second group (25) FS associated to factor XIII and aprotinin (Beriplast; Aventis-Beringher) and the third group (25) was the control. Animals were sacrificed by prolonged diethyl inhalation on days 7, 14 and 28 after surgery. Animal craniums were dissected and submitted to a decalcification, and preparated for H&E light microscopy. The morphometric study was performed by means of an interactive computerized image analysis system KS400 (Zeiss, Jena). New bone formation was carefully delimited in four different alveolar regions (apical, two middle areas and cervical) of each specimen. The data were statistically analyzed using multiple regression, ANOVA and Tukey test. Results showed that the amount of alveolar bone formation (μm) in the control group and commercial sealant was statistically similar. However, alveolus receiving homemade sealant presented less amount of new bone formation comparing to commercial sealant and control group (p=0.0034) (figure 1). The present study demonstrated that homemade fibrin sealant delays osteogenic formation. Commercial sealant did not improve alveolar repair however, the amount of new bone formation was slightly higher comparing to the control, probably due to the factor XIII present in this sealant. Figure Figure


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