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1.
Braz. j. biol ; 84: e257070, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1360228

RESUMO

Abstract Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.


Resumo Nanopartículas (NPs) são partículas insolúveis com diâmetro inferior a 100 nanômetros. Dois métodos principais têm sido utilizados na terapia ortodôntica para evitar a aderência microbiana ou a desmineralização do esmalte: NPs são incluídas em adesivos ortodônticos ou resinas acrílicas (fluoro-hidroxiapatita, fluorapatita, hidroxiapatita, SiO2, TiO2, prata, nanopreenchimentos) e NPs são revestidas nas superfícies de equipamentos ortodônticos, ou seja, uma camada fina de TiO2 dopado com nitrogênio nas superfícies do braquete. Embora o uso de NPs em ortodontia possa tornar acessível modernos recursos, pesquisas anteriores analisaram as características antibacterianas ou físicas por um período limitado de tempo, variando de 24 horas a várias semanas, por isso devem ser compreendidos os limites dos estudos in vitro. A eficácia de longo prazo de materiais ortodônticos com base em nanotecnologia ainda não foi confirmada de forma conclusiva, o que exige mais estudos, bem como potenciais preocupações de segurança (efeitos tóxicos) associadas ao tamanho da NP.

2.
Braz. j. oral sci ; 21: e227903, jan.-dez. 2022. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1355005

RESUMO

Aim: To evaluate the accuracy and the validity of orthodontic diagnostic measurements, as well as virtual tooth transformations using a generic open access 3D software compared to OrthoAnalyzer (3Shape) software; which was previously tested and proven for accuracy. Methods: 40 maxillary and mandibular single arch study models were duplicated and scanned using 3Shape laser scanner. The files were imported into the generic and OrthoAnalyzer software programs; where linear measurements were taken twice to investigate the accuracy of the program. To test the accuracy of the program format, they were printed, rescanned and imported into OrthAnalyzer. Finally, to investigate the accuracy of editing capabilities, linear and angular transformation procedures were performed, superimposed and printed to be rescanned and imported to OrthoAnalyzer for comparison. Results: There was no statistically significant difference between the two groups using the two software programs regarding the accuracy of the linear measurements (p>0.05). There was no statistically significant difference between the different formats among all the measurements, (p>0.05). The editing capabilities also showed no statistically significant difference (p>0.05). Conclusion: The generic 3D software (Meshmixer) was valid and accurate in cast measurements and linear and angular editing procedures. It can be used for orthodontic diagnosis and treatment planning without added costs


Assuntos
Software , Moldes Cirúrgicos , Imageamento Tridimensional , Modelos Dentários
3.
J. Health Biol. Sci. (Online) ; 10(1): 1-4, 01/jan./2022. ilus
Artigo em Inglês | LILACS | ID: biblio-1366891

RESUMO

Aim: to evaluate the internet searches for Invisalign® in Brazil and worldwide between 2018 and 2021, using the Google Trends tool. Methods: An infodemiological study was carried out. The relative search volume (RSV) for the term "invisalign" in Google platform was retrieved for each year of study, both in Brazil and worldwide, using a standard procedure. Results and Conclusion: Both in Brazil and worldwide, there was a statistically significant increase in RSV between 2018 and 2021 (all p <0.05), indicating progressively more interest in Invisalign® clear aligner on the internet.


Objetivo: avaliar as buscas na internet por Invisalign® no Brasil e no mundo entre 2018 e 2021, utilizando a ferramenta Google Trends. Métodos: Foi realizado um estudo infodemiológico. O volume relativo de busca (RSV) para o termo "invisalign" na plataforma Google foi recuperado para cada ano de estudo, tanto no Brasil quanto no mundo, utilizando um procedimento padrão. Resultados e Conclusão: Tanto no Brasil quanto no mundo, houve um aumento estatisticamente significativo do RSV entre 2018 e 2021 (todos p <0.05), indicando progressivamente mais interesse pelo alinhador transparente Invisalign® na internet.


Assuntos
Aparelhos Ortodônticos Removíveis , Ortodontia , Epidemiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-35912539

RESUMO

BACKGROUND: During the debonding phase every clinician has to take care of preserving the enamel structure and tooth temperature. The objective of this study is to analyze in vitro the increase of the pulp chamber temperature and the wearing of enamel surface, during adhesive removal after debonding. METHODS: 60 extracted human teeth were selected. An orthodontic bracket was bonded on each tooth and after bracket removal, intraoral scanner pictures were used to evaluate ARI for each tooth. 3 different burs were tested: Tungsten-carbide multiple blade, Arkansas stone and Ceramic bur. A mechanical arm controlled by a dedicated software was used to reproduce a repeatable act of composite removal. To analyze in vitro the pulp chamber temperature during the composite removal procedure, teeth were treated endodontically placing a thermocouple through the root canal from the apex. A software registered temperature changes in a continuous manner. The enamel surface of every tooth was tested after the removal of composite with an optical stereoscopic microscope. RESULTS: An association existed between maximum internal pulp chamber temperature variation and irrigation (P-value < 0.0001) and between maximum internal pulp chamber temperature variation and bur type (P-value = 0.0133), with a significantly lower temperature increase produced by the Arkansas bur. A significant difference among groups was detected for ESI and EDI assessment (P-value = 0.002, P-value = 0.010). CONCLUSIONS: Considering the initial setup, temperature variation analysis showed more conservative results using the Arkansas burs with irrigation. ESI and EDI indexes showed significant enamel surface damage using Tungsten-carbide burs.

5.
Aust Dent J ; 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35916055

RESUMO

The primary dental care clinician is in a prime position to identify deviations from normal dental development. Disturbances can affect any new erupting tooth. The objective of this narrative review is to describe several situations in which eruption disturbances can arise during the mixed dentition. It will provide an overview of the orthodontic considerations of these disturbances in addition to key summary points on interceptive management, based on the best available evidence. © 2022 Australian Dental Association.

6.
Int J Dent Hyg ; 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35924398

RESUMO

BACKGROUND: The risk of periodontal diseases development increased in patients with malocclusion undergoing orthodontic treatment. Thus, the aim of this study was to examine the efficacy of the use of adjunctive rinses with nano-Argentum to standard oral hygiene regimen in subjects wearing fixed orthodontic appliances MATERIALS AND METHODS: Eighty patients were observed for 1 year. They were divided in two groups: in test group patients were instructed to rinse with non-ionic colloidal silver solution according to protocol for 6 months as an adjunct to standard; in control group the patients followed the standard oral hygiene regimen. Index of efficiency of oral hygiene (PHPm), community periodontal index (CPI), and papillary-marginal-alveolar index (PMA) were evaluated before treatment, and after one and six months. For statistics analysis Mann-Whitney, Kruskal-Wallis tests and Pearson criterion were used. RESULTS: Baseline hygiene levels in two groups had no differences. Oral hygiene indices were significantly lower in the test group in comparison with control after 1 month (PHPm = 0.38 ± 0.18 and 1.19±0.45 respectively, p<0.01; PMA = 11.78±8.5 and 47.25±20.9 respectively, p<0.05; CPI = 0.65±0.53 and 1.53±0.77 respectively, p<0.01) and 6 months (PHPm = 0.5±0.2 and 1.2±0.4 respectively, p <0.01; PMA = 11.62±19.6 and 66.33±27.9 respectively, p<0.01; CPI = 0.63±0.73 and 1.68±0.78 respectively, p<0.01). CONCLUSIONS: The use of the test solution as an adjunct to standard oral hygiene provided a significant beneficial effect in terms of oral hygiene in patients undergoing orthodontic treatment.

7.
Int Orthod ; : 100669, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35918281

RESUMO

INTRODUCTION: The objective of the study was to compare outcomes in terms of Bleeding index (BI), Gingival Index (GI) and Orthodontic Plaque Index (OPI) with videographic and plaque disclosing tablets (PDT) versus verbal instructions in adult orthodontic patients undergoing fixed appliance treatment (FAT). MATERIALS AND METHODS: Adult orthodontic patients were recruited form outpatient orthodontic clinic who fulfilled the inclusion criteria and were randomly allocated to three groups i.e., video, PDT AND VERBAL GROUPS: Subjects who had gingivitis as assessed by the Bleeding Index (BI), Gingival Index (GI) and Orthodontic Plaque Index (OPI) were recruited. Pre- and post-interventional measurements were taken at two intervals only for BI, GI and OPI. The primary outcome was to evaluate mean change in the BI, GI and OPI in the three study groups after six weeks. A computer-generated randomization list was used to allocate subjects to one of the three study groups using a random permuted block sampling of 6 and 9 to randomize the samples. RESULTS: A total of 99 subjects were assessed for eligibility out of which 96 participants were randomized as three of the participants declined to be part of this trial. The mean change in the oral hygiene indices score were assessed and we found no statistically significant difference among the three interventional groups. Pre- and postinterventional results showed statistically significant improvement in the oral hygiene indices for video and PDT group. No statistically significant difference for age, gender and education level on oral hygiene indices. Simple linear regression showed that video group produced significantly higher mean OPI change as compared to other groups. CONCLUSIONS: Visual aids performed better than verbal instructions. Gender, age, and education level did not have a statistically significant impact on oral hygiene indices.

8.
J Periodontal Res ; 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35930702

RESUMO

BACKGROUND AND OBJECTIVES: The molecular mechanisms mediating external root resorption are poorly understood. Interleukin-33 (IL-33) expression increased remarkably in the periodontal ligament (PDL) under orthodontic loading. The IL-33-driven responses are delicately cell type- and tissue context-dependent. It is unknown how IL-33 act on osteoclastogenesis in the context of root surface. This study aimed to investigate the effect of IL-33 on osteoclastogenesis in the PDL under mechanical loading. MATERIALS AND METHODS: C57BL/6J mice were treated with injections of phosphate buffer saline (PBS) or recombinant mouse IL-33 (rmIL-33, 6 µl, 30 µg/ml), and subjected to models of orthodontic tooth movement. Tartrated resistant acid phosphates (TRAP)-positive cells and IL-33 expressions were examined in the PDL. IL-33 release from human PDL cells (hPDLCs) was detected by ELISA. Cementoblast-like (OCCM-30) cells were cultured in the presence of rmIL-33 to examine the release of osteoclast-regulatory proteins. The effects of rmIL-33 on osteoclastogenesis were examined in vitro in cultures of bone marrow macrophages (BMMs) and in BMMs-OCCM-30 cocultures. Expressions of osteoclast-specific or -related genes and proteins were investigated in BMMs-OCCM-30 cocultures treated with or without rmIL-33, in the presence or absence of granulocyte-macrophage colony-stimulating factor (GM-CSF) neutralizing antibody. RESULTS: Interleukin-33 expressions were upregulated in the PDL under orthodontic loading. Static compressive force enhanced expression and release of IL-33 from hPDLCs. Administration of rmIL-33 resulted in reduced number of TRAP-positive cells in the PDL, and inhibited osteoclast differentiation from BMMs in vitro. OCCM-30 cells had varied osteoprotegerin (OPG) / receptor activator for nuclear factor-κB ligand (RANKL) secretion and increased release of GM-CSF under rmIL-33 stimulation. Treatment with rmIL-33 in BMMs-OCCM-30 cocultures resulted in inhibited differentiation and decreased activity of osteoclasts, and these effects were partially reversed by GM-CSF neutralizing antibody. CONCLUSIONS: Interleukin-33 inhibits osteoclastogenesis in the PDL under orthodontic loading. The anti-osteoclastogenic effects were mediated partly by directly affecting osteoclast precursors and partly by cementoblast-mediated release of GM-CSF.

9.
Artigo em Inglês | MEDLINE | ID: mdl-35931615

RESUMO

INTRODUCTION: Improvement in facial esthetics is a major reason for seeking orthodontic treatment. Soft tissues responsible for esthetics show a variable response to the movement of underlying teeth during orthodontics. METHODS: The purpose of this cross-sectional study was to analyze the response of soft tissues and compare it among groups presenting with different lip thickness and competence. It was carried out on 37 patients with Class I and Class II Division 1 malocclusion who had undergone extractions of maxillary first premolars and had completed their orthodontic treatment. Data were obtained by corresponding lateral cephalometric radiographs taken before and at the end of orthodontic treatment. Association was analyzed with a Pearson correlation test. Differences among groups exhibiting varying competency and lip thickness were tested with an independent sample t test. A P value of ≤0.05 was considered statistically significant. RESULTS: Pearson correlation revealed significant associations among incisor tip retraction with lip base retraction (r = 0.68), lip base thinning (r = 0.41) and vermilion retraction (UV) (r = 0.73). Regression analysis showed a moderate increase in lip length (AB) and thickness at vermilion, which were 0.11 mm and 0.15 mm for each mm of incisor retraction at the tip, whereas stronger effects were observed for UV (0.38 mm) and lip base retraction (0.55 mm). There was significantly more lip base thinning (P = 0.03) and UV (P = 0.04) in the incompetent group compared with the competent group. The AB increased significantly in the sample with thicker lips (P = 0.01). Pearson correlation coefficient showed a strong association of lip retraction at the base and vermilion with the incisor movement at the cervical area, for competent and incompetent lips, and thicker and thinner lips. CONCLUSIONS: Lip retraction at vermilion and lip base thinning was significantly more in patients with incompetent lips, whereas the AB increased significantly more in the group with thicker lips.

10.
J Oral Rehabil ; 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35932210

RESUMO

BACKGROUND: Bone homeostasis is a dynamic process maintained by osteoblasts and osteoclasts, which may be regulated by excessive mechanical stress (EMS). OBJECTIVES: Our study aims to explore the relationship between osteogenic differentiation of BMSCs and EMS-activated osteoclast differentiation of RAW 264.7 cells in order to optimize orthodontic treatment. METHODS: We established the model of EMS in vivo and in vitro. In vivo, HE, Safranin-O staining, micro-CT, and immunofluorescence double-labeling were utilized to assess the changes in condylar, the distributions of osteoblasts, osteoclasts and MAPKs. In vitro, the effects of EMS-activated osteoclast differentiation exerting on osteogenic differentiation of BMSCs were observed by Western Blot, qRT-PCR and Alizarin Red staining. Furthermore, the role of MAPKs in this progress was explored by using inhibitors of MAPKs and co-culture supernatants. RESULTS: In vivo, EMS led to the degradation of condylar cartilage and destruction of subchondral bone, diagnosed as temporomandibular joint osteoarthritis (TMJ OA). Osteoclasts and osteoblasts were both enriched in subchondral bone, but osteoclast predominated. The expressions of p-JNK, p-ERK1/2, and p-p38 were all activated in vitro and in vivo, which were localized mainly in the Trap+ area in subchondral bone. Interestingly, only the inactivation of p-ERK1/2 in osteoclasts significantly inhibited the osteogenic differentiation of BMSCs in vitro. This revealed that p-ERK1/2 played a key role in the osteoclasts-induced osteogenic differentiation of BMSCs. CONCLUSION: Our results proved that EMS led to TMJ OA, in which up-regulated p-ERK1/2 in osteoclasts was mechanosensitive and facilitated the osteogenic differentiation of BMSCs.

11.
Artigo em Inglês | MEDLINE | ID: mdl-35936931

RESUMO

Cl III malocclusion with a significant skeletal component presents a therapeutic challenge during adolescence. This article presents the encouraging results of an individualized two-stage treatment approach adopted for successful nonsurgical correction of severe skeletal Cl III malocclusion in an adolescent girl after the onset of puberty. An orthopedic approach involving simultaneous alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocol and protraction facemask (PFM) therapy was adopted in phase 1 to correct the sagittal skeletal discrepancy. In phase 2, fixed orthodontic therapy aided by the interim use of a modified occlusal settling appliance was undertaken to obtain well-interdigitated occlusion. Meticulously planned and well-executed orthopedic and orthodontic approach, combined with good patient compliance and favorable growth pattern, helped establish well-balanced facial harmony with a proper maxillomandibular relationship and satisfactory overjet and overbite. The results remained stable during the 4-year follow-up. Alt-RAMEC-PFM therapy accompanied by fixed mechanotherapy is a viable option to treat severe skeletal Cl III malocclusion in adolescents.

12.
Artigo em Inglês | MEDLINE | ID: mdl-35936932

RESUMO

Background. The use of sports and energy drinks has drastically increased in the adolescent population. This population often is in orthodontic treatment, and the use of such drinks with poor oral hygiene promotes the development of white spot lesions (WSLs). Quantifying the degree of the lesion has been limited in the past. The hypothesis was that the Canary Caries Detection System could be used to quantify the degree of WSLs caused by different commercial beverages. Methods. A total of 105 extracted human premolars were divided into seven groups (n=15). Each group was tested in one of six beverages or a phosphate-buffered solution (control). The teeth were exposed to its beverage three times a day for 15 minutes for 28 days. Canary numbers and ambient light and fluorescent photographs were collected at baseline (T0 ) and on days 14 (T1 ) and 28 (T2 ). Results. The paired t test and one-way ANOVA found that T0 to T1 measurements were statistically significant (P<0.0015) and that T0 to T2 measurements were statistically significant (P<0.0001). Visually, the ambient light photographs and fluorescent photographs from T0 to T1 and T1 to T2 correlated with the increase in Canary numbers. Conclusion. This in vitro study revealed a statistically significant increase in the T0 to T1 Canary numbers and a statistically significant increase from T0 to T2 Canary numbers for all the test beverages. Changes in Canary numbers indicated significant changes in mineral density (i.e., demineralization) and development of WSLs on enamel after exposure to sports and energy beverages.

13.
Artigo em Inglês | MEDLINE | ID: mdl-35936939

RESUMO

Background. This study aimed to evaluate the visual facial perception in response to scars associated with repaired cleft lip (CL) on a male adolescent patient, as assessed via eye-tracking. Methods. Index of orthodontic treatment need (IOTN) malocclusions, grades 1, 5, and 8 were added to the frontal view facial image of an adolescent male model showing asymmetries of the nose and upper lip after CL surgery using the software Photoshop CS5® software. The eye movements of 91 laypeople observers were tracked by an Eye Tribe infrared sensor connected to OGAMA© software. A Kruskal-Wallis test was used to identify differences in total fixation time and time until the first fixation for the areas of interest. A visual analog scale (VAS) of attractiveness was also used in the study. Statistical analysis was performed adopting a significance level of P<0.05. Results. The area of interest (AOI) were found to be the mouth and teeth, which were more focused on gazed at than any other area, regardless of the grade of IOTN. For observers of different ages, there were significant differences in the time until the first fixation on the scar of the repaired CL region for IOTN grade 1 (P=0.007). Images showing IOTN grade 1 repaired CL regions received the highest VAS scores. The older the age, the greater the tendency to give a higher VAS score for the same malocclusion. Conclusion. The presence of a CL scar on the upper lip did not attract the eye of laypeople observers of different ages, regardless of the degree of malocclusion in the non-smile image. The age of the observers did influence the perception of attractiveness, with older observers giving higher scores than younger ones. As the severity of the malocclusion increased, they were found to be less attractive.

14.
Front Dent ; 19: 7, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937146

RESUMO

Objectives: Use of miniscrews has become very common in orthodontic treatment of patients. Following tissue manipulation during miniscrew placement, bacteremia may occur, which is important in patients susceptible to infective endocarditis. This study aimed to investigate the possibility of bacteremia following orthodontic miniscrew placement. Materials and Methods: The present quasi-experimental study was conducted on 30 orthodontic patients, including 11 males (36.7%) and 19 females (63.3%) with a mean age of 23.67±4.87 years, who required miniscrew placement in their treatment plan. Two blood samples were taken from the patients for aerobic and anaerobic cultures right before and 30-60 seconds after miniscrew placement. To investigate the presence of bacteremia, the blood samples were incubated in an automated blood culture machine for five days. The standard biological methods were used for the positive sample(s) to identify the type of bacteria. Data analysis was performed using the McNemar test. Results: The blood samples of 29 patients were negative for the bacteria before and after miniscrew placement. Blood sample of one patient was positive for aerobic and anaerobic bacteria after miniscrew placement. However, bacteremia was negative in the initial (preplacement) blood samples for both aerobes and anaerobes. Conclusion: Miniscrew placement in orthodontic patients was not associated with bacteremia.

15.
Front Dent ; 19: 5, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937155

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the effect of saliva contamination on shear bond strength (SBS) of orthodontic brackets bonded by a self-adhering composite compared with a conventional adhesive. MATERIALS AND METHODS: This in vitro, experimental study investigated 40 human premolars. The teeth were randomly divided into four groups based on the adhesive type and bonding condition: (I) Vertise Flow composite without saliva contamination (VF), (II) Vertise Flow composite with saliva contamination (VF/S), (III) Transbond XT composite without saliva contamination (TXT), and (IV) Transbond XT composite with saliva contamination (TXT/S). After the preparation step, brackets were bonded to the buccal surface of the teeth, and samples were mounted in acrylic blocks, incubated at 37°C for 24 hours, and underwent thermocycling between 5- 55°C. Next, the SBS was measured by a universal testing machine. Data were analyzed by ANOVA and Tukey's test. P<0.05 was considered statistically significant. RESULTS: ANOVA showed a significant difference in SBS among the groups (P<0.001). The highest SBS was achieved in the TXT group (26.63±9.09 MPa), followed by TXT/S (13.69±4.23 MPa), VF/S (3.68±1.49 MPa), and VF (3.04±1.73 MPa). CONCLUSION: Saliva contamination did not have a significant effect on SBS of brackets bonded with Vertise Flow. However, it did not provide acceptable bond strength for orthodontic bracket bonding in the clinical setting.

16.
Natl J Maxillofac Surg ; 13(1): 147-152, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35911814

RESUMO

Impacted maxillary canine is frequently encountered in clinical practice. Being the cornerstone of the dentition, orthodontic traction of impacted canine is always desirable in order to achieve successful functional occlusion. The aim of this case series is to illustrate different methods employed for orthodontic traction of maxillary impacted canine.

17.
Photodiagnosis Photodyn Ther ; : 103051, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35932962

RESUMO

BACKGROUND: The present study evaluated the physico-mechanical and antimicrobial properties of ultrasound waves-activated modified-resin glass ionomer containing nanosonosensitizers such as nano-curcumin (n-Cur), nano-emodin (n-Emo), and nano-quercetin (n-Qct) against Streptococcus mutans biofilm on the surface of modified-resin glass ionomer bonded orthodontic bands. MATERIALS AND METHODS: A total of 50 human molar teeth were used in this study. The shear bond strength (SBS), adhesive remnant index (ARI), setting time, and fluoride release of modified orthodontics cement containing different concentrations of n-Cur, n-Emo, and n-Qct (0, 2, 5, and 10%) were measured. The antimicrobial effectiveness was assessed against S. mutans by the biofilm inhibition test, and the Log10 colony-forming unit (CFU)/mL was evaluated. RESULTS: SBS and setting time of modified glass ionomer decreased compared with the control group. 5% n-Emo, 2% n-Qct, and 5% n-Cur were the highest concentrations that had an insignificant difference in comparison with Transbond XT (P=0.647, 0.819, and 0.292, respectively). The groups were not significantly different in terms of ARI score (P>0.05). The highest and lowest setting time belonged to the control and 5% n-Emo groups, respectively; this difference in setting time was significant (P<0.05). Ultrasound waves and 0.2% CHX significantly reduced S. mutans biofilms compared with the control group (P<0.001), and minimum S. mutans colony count was shown in 0.2% CHX and 5% n-Emo groups. The addition of nanosonosensitizers to the glass ionomer did not compromise the fluoride release of the glass ionomer. CONCLUSION: It could be concluded that resin-modified glass ionomer containing ultrasound waves-activated 5% n-Emo reduces S. mutans biofilm around orthodontic bands with no adverse effect on SBS, ARI, and its application in the clinic.

18.
Stem Cell Res Ther ; 13(1): 401, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35932080

RESUMO

INTRODUCTION: The basis of orthodontic tooth movement (OTM) is the reconstruction of periodontal tissue under stress. Increasing the speed of OTM has always been the focus of attention. OBJECTIVES: Periodontal ligament stem cells (PDLSCs) are direct effector cells of mechanical force, but the mechanism by which PDLSCs sense mechanical stimuli is unclear. METHODS: Human PDLSCs (hPDLSCs) were analyzed in the presence or absence of force loading with the Flexcell loading system in vitro. Then, periodontal tissues were analyzed after mechanical stimulation in vivo. In addition, cells in a confined microenvironment were analyzed to observe changes in the cytoskeleton and migration. Finally, TRPC6-/- mice were used to further verify the effect of TRPC6. After force application, the OTM distance, bone marrow density (BMD), TRPC6 and COL1 expression, and TRAP staining were evaluated in periodontal tissues. RESULTS: RNA sequencing (RNA-seq) and western blot analyses revealed that TRPC6 was important during mechanical force application to hPDLSCs. Appropriate mechanical force application also induced TRPC6 activation in the OTM model and the confined microenvironment. Under a slightly confined microenvironment, treatment with the TRPC6 inhibitor SKF96365 and TRPC6 knockout decreased the migration speed of hPDLSCs and mouse bone marrow mesenchymal stem cells (mBMSCs). In addition, TRPC6-/- mice showed lower OTM distances and reduced osteogenic and osteoclastic differentiation. CONCLUSION: In summary, TRPC6 activation in PDLSCs mediated by appropriate mechanical force application contributes to periodontal tissue reconstruction. PDLSCs modulate periodontal tissue remodeling under appropriate mechanical stimulation through TRPC6; however, under excessive stress, alveolar bone and tooth roots are readily absorbed. Under this condition, environmental factors play a leading role, and the regulatory effect of TRPC6 is not obvious.

19.
Biochem Biophys Res Commun ; 624: 16-22, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35932574

RESUMO

Rab GTPases, the largest group of small monomeric GTPases, have been shown to participate in membrane trafficking involving many cellular processes. However, their roles during osteoblastic differentiation remain to be elucidated. In this study, we investigated Rab GTPase involvement in osteoblastic differentiation. Protein levels of a series of Rabs (Rab4, Rab5, Rab7, Rab9a, Rab11a/b, and Rab27) were increased during osteoblastic differentiation of MC3T3-E1 cells, and the Rab11a/b levels were particularly pronounced in the presence of Rho-associated coiled-coil-containing protein kinase (ROCK) inhibitor, an activator of osteoblastogenesis. We subsequently investigated the functional contribution of Rab11a and Rab11b during osteoblastic differentiation. The alkaline phosphatase (ALP) levels were reduced by Rab11b depletion but not by Rab11a depletion. Because our result suggested that Rab11a and Rab11b could be regulated downstream of Runx2 (Runt-related transcription factor 2), a key transcription factor for osteoblastic differentiation, we investigated the effects of the double knockdown of Runx2 and Rab11a or Rab11b on osteoblastic phenotypes. The double knockdown significantly reduced ALP activity as well as collagen deposition compared with single Runx2 knockdown. Furthermore, the Rab11a and Rab11b response to mechanical stress in vivo was investigated using a mouse orthodontic tooth movement model. Rab11a and Rab11b expression was enhanced in the periodontal ligament, where bone formation is activated by tensile stress. This study shows that Rab11a and Rab11b are regulated downstream of Runx2 in osteoblastic differentiation, and their expressions are also controlled by tensile stress.

20.
Am J Orthod Dentofacial Orthop ; 162(2): 257-263, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35933158

RESUMO

INTRODUCTION: Accurate landmark identification is a prerequisite for accurate and reliable biomedical image analysis. Orthodontic study models are valuable tools for diagnosis, treatment planning, and maintaining complete records. The purpose of this study was to evaluate the reliability and validity of a software program (Align Technology, Inc) as a tool for automatic landmark location. METHODS: Using digital intraoral scans of 10 dental arches, 4 calibrated human judges independently located cusp tips and interproximal contacts. The same landmarks were automatically identified by the software. Intraclass correlation coefficient (Cronbach α), absolute mean errors, and regression analysis were calculated. In addition, Bland-Altman 95% confidence limits were also applied to the data to graphically display agreement on landmark identification between the human judges and the software. RESULTS: The intraclass correlation coefficient between the software and the human judges' average for the x-, y-, and z-coordinates for all landmarks was excellent, at 1.0, 1.0, and 0.98, respectively. The regression analysis and Bland-Altman plots show no systematic errors for agreement on landmark identification between the human judges and the software. CONCLUSIONS: Landmark location was nearly identical between the software and the human judges, making the methods interchangeable.

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