Telma Martins de Araújo

Ancoragem esquelética em Ortodontia com miniimplantes

Temporary anchorage devices, such as mini-implants, have been widely used over the last few years. These devices are very important where anchorage is a major factor for the successful outcome of orthodontic treatment. The authors will comment on the broader aspects of orthodontic treatment with application of mini-implants, choice of implant sites, discussing their indications, surgical procedures, post-surgical oral hygiene care and the most frequent complications.

Laser-Induced Alveolar Bone Changes During Orthodontic Movement: A Histological Study on Rodents

OBJECTIVE The aim of this study was to assess by light microscopy changes in alveolar bone during orthodontic movement in rats. BACKGROUND Orthodontic movement causes both removal and deposition of bone tissue. The use of laser phototherapy (LPT) is considered an enhancement factor for bone repair. METHODS Thirty Wistar rats were divided into two groups (n = 15) and subdivided according to animal death (7,13, and 19 days). Half of the animals in each group were treated with LPT during orthodontic movement. After animal death, specimens were processed and underwent histological and semi-quantitative analyses (HE and Sirius red). RESULTS LPT-irradiated specimens showed significantly higher numbers of osteoclasts when compared with controls at both 7 (p = 0.015) and 19 (p = 0.007) days, as well as significant increases in the number of osteoblasts (p = 0.015) between days 7 and 13. The amount of collagen matrix was significantly reduced between days 7 and 13 at both pressure and tension sites in controls (p = 0.015) but not in LPT-treated animals. LPT-treated subjects showed significantly greater deposition of collagen matrix at the pressure site at both the thirteenth (p = 0.007) and nineteenth days (p = 0.001). At the tension site, a significant increase in the amount of collagen matrix was observed in non-irradiated specimens (p = 0.048) between days 7 and 19. CONCLUSIONS LPT caused significant histological changes in the alveolar bone during induced tooth movement, including alterations in the number of both osteoclasts and osteoblasts and in collagen deposition in both pressure and tension areas.

Benefits of the use of the CO2 laser in orthodontics

Esthetics is an important factor for patients seeking orthodontic treatment, and not always is the orthodontist able to make adjustments on the gingival contour, and this aspect is neglected. Many orthodontists are familiar with the name laser. However, there is a lack of information regarding their application on the orthodontic practice. There are several options for the use of CO2 lasers on surgical procedures of interest to orthodontists, especially on soft tissues. There is no evidence that the use of the CO2 laser has any side effect or contraindication on surgical procedures. This paper reports a series of surgical procedures carried out on orthodontic patients. It is concluded that the carbon dioxide laser not only allows surgeons to enhance current surgical options for treatment but also have contributed to the evolution of a variety of new procedures that are now commonplace in oral surgery, and its use shows several benefits for the orthodontic patient.

Avaliação da radiografia cefalométrica lateral como meio de diagnóstico da hipertrofia de adenoide

INTRODUCTION: One of the most usual causes of mouth breathing is adenoids hypertrophy with reduction of the nasopharyngeal space. The most precise diagnostic methods are magnetic resonance and nasal endoscopy, because they make possible a three dimension image of the nasopharynx. However, in Dentistry, cephalometric radiography is the method used in the majority of cases. That is why it is so important the evaluation of the efficacy of this diagnostic method. AIM: The aim of this paper is to determine the efficacy of the lateral cephalometric radiography in diagnosing adenoids hypertrophy, comparing this method to the nasal endoscopy. METHODS: Thirty patients (7 to 12 years), with no history of otolaryngological surgery, were evaluated. All of them were submitted to a nasal endoscopy and a lateral cephalometric radiography. In the endoscopic exams it was registered the percentage of nasopharyngeal obstruction and in the radiographic exams it was registered the minor nasopharyngeal dimension. RESULTS: The results of the exams showed a strong correlation with each other (r = - 0.793, p-value < 0.01). After that, reliability tests to the radiographic diagnose were performed, assuming that 75% (endoscopic exams) and 5mm (radiographic exams) were the limit values to the determination of the diagnose of severe adenoids hypertrophy. The radiographic exam showed a sensibility of 75%, specificity of 86.3%, positive predictive value of 66.7%, negative predictive value of 90.4% and an exactness of 83.3%. Therefore, lateral cephalometric radiography is an efficient method of adenoids hypertrophy diagnose. It was proved by the strong correlation of its results with the results of the nasal endoscopy, that is considered a method of excellence for diagnosing this condition.

Tooth Movement After Infrared Laser Phototherapy: Clinical Study in Rodents

OBJECTIVES The aim of this research was to investigate the influence of low-power laser on tooth movement in rats. BACKGROUND Tooth movement is closely related to the process of bone remodeling. The biologic result, with the application of a force to the tooth, is bone absorption on the pressure side and neoformation on the traction side of the alveolar bone. The laser photobiomodulation is capable of providing an increase in cellular metabolism, blood flow, and lymphatic drainage. METHODS Thirty young-adult male Wistar rats weighing between 250 and 300 g were divided into two groups, control and experimental, containing 15 animals each. The animals received orthodontic devices calibrated to release a force of 40 g/F, with the purpose of moving the first upper molar mesially. Low-intensity laser, wavelength 790 nm, was used in the experimental group; the dose was 4.5 J/cm(2) per point, mesial and distal, on the palatal side, 11 J/cm(2) on the buccal side, and this procedure was repeated every 48 h, totaling nine applications. The active movement was clinically evaluated after 7, 13, and 19 days. RESULTS AND CONCLUSION The results showed no statistically significant difference, p = 0.079 (T0-T7), p = 0.597 (T7-T13), and p = 0.550 (T13-T19) between the laser and control groups on the amount of tooth movement in the different times evaluated. It may be concluded that laser phototherapy, with the parameters in the present study, did not significantly increase the amount of tooth displacement during induced orthodontic movement in rodents.

Effect of Laser Phototherapy on the Hyalinization Following Orthodontic Tooth Movement in Rats

OBJECTIVE We aimed to assess histologic changes after the use of laser phototherapy (LPT) during induced tooth movement with 40 g/F on young adult male rats. BACKGROUND DATA Hyalinization is a sterile necrosis at the pressure zone of the periodontal ligament observed during the initial stages of the orthodontic movement, and extensive hyaline areas might cause an important delay in the tooth movement. The use of LPT is considered an enhancement factor for bone repair, as it stimulates microcirculation as well as the cellular metabolism. MATERIALS AND METHODS Thirty animals were divided into two groups (n=15), named according to the time of animal death (7, 13, and 19 days). Half of the animals in each group were subjected to irradiation with infrared (IR) laser (λ790 nm, round shaped beam, 40 mW, continuous wave (CW), diameter=2 mm (0.0314 cm(2)), 1.273 W/cm(2), time=2×112 sec+1×275 sec (total time 499 sec), 2×142.6/4.48 J+1×350/11 J, 635.2 J/cm(2)/20 J/ session), during orthodontic movement, the other half were used as nonirradiated controls. After animal death, specimens were sectioned, processed, and stained with hematoxylin and eosin (HE) and Sirius Red, and were used for semi-quantitative histologic analysis by light microscopy. Data were statistically analyzed. RESULTS We demonstrated that LPT positively affected an important aspect of dental movement; the hyalinization. In the present study, we found a significant reduced expression of hyalinization after 19 days. On irradiated subjects, hyalinization was increased at day 7 with significant reduction at day 13. CONCLUSIONS It is possible to conclude that the use of laser light caused histologic alterations during the orthodontic movement characterized by increased formation of areas of hyalinization at early stages, and late reduction when compared to nonirradiated animals.

Estudo comparativo entre traçados cefalométricos manual e digital, através do programa Dolphin Imaging em telerradiografias laterais

OBJECTIVE: The purpose of this study was to compare angular and linear cephalometric measurements obtained through manual and digital cephalometric tracings using Dolphin Imaging® 11.0 software with lateral cephalometric radiographs. METHODS: The sample consisted of 50 lateral cephalometric radiographs. One properly calibrated examiner performed 50 manual and 50 digital cephalometric tracings using eight angular measurements (FMA, IMPA, SNA, SNB, ANB, 1.NA, 1.NB, Y-Axis) and six linear measurements (1-NA, 1-NB, Co-Gn, Co-A, E Line-Lower lip and LAFH). Results were assessed using Students t-test. RESULTS: The results showed no statistically significant differences in any of the assessed measurements (p> 0.05). CONCLUSIONS: Conventional and computerized methods showed consistency in all angular and linear measurements. The computer program Dolphin Imaging® 11.0 can be used reliably as an aid in diagnosing, planning, monitoring and evaluating orthodontic treatment both in clinical and research settings

Reliability of digital orthodontic setups

OBJECTIVE To evaluate the reliability of digital orthodontic setup technology by comparing it with manual setups and models cast at the end of orthodontic treatment. MATERIALS AND METHODS Initial models, manual setups, and final models of 20 patients were used. The initial and final models, as well as the manual setups, were scanned using a 3Shape R-700 scanner, while the digital setups were fabricated based on the initial models using 3Shape OrthoAnalyzer software. Evaluation of the models based on the manual setup, digital setup, and final models of each patient was performed using the following linear measurements: intercanine widths, intermolar widths, and length of the upper and lower dental arches. RESULTS The results disclosed that none of the measures assessed through the manual setup, digital setup, and final models showed statistically significant differences (P > .05). CONCLUSIONS Based on these findings, it can be inferred that digital setups are as effective and accurate as manual setups and constitute a tool for diagnosing and treatment planning that can be reliably reproduced in orthodontic treatments.

Coleta e cultura de células-tronco obtidas da polpa de dentes decíduos: técnica e relato de caso clínico

INTRODUCTION: Stem cells (SCs) are capable of inducing tissue regeneration and are, therefore, potentially therapeutic. Similarly to bone marrow and umbilical cords, dental pulp is one of the available sources of SCs. The fact that these cells are easily accessible and that deciduous teeth are not vital organs, and are normally discarded after exfoliation, make them particularly attractive for use in safety and viability tests. OBJECTIVE: To describe the collection, isolation and culture of SCs obtained from the pulp of deciduous teeth as well as their characterization by flow cytometry, and the induction of differentiation into osteogenic and adipogenic lineages. METHODS: SCs were obtained in a relatively straightforward manner and showed good proliferative capacity, even from a small amount of pulp tissue. RESULTS: Analysis by flow cytometry confirmed the characteristics of mesenchymal SCs with low expression of CD34 and CD45 antigens, which are markers for hematopoietic cells, and high levels of expression of CD105, CD166, CD90 and CD73 antigens, which are markers for mesenchymal SCs. Cell plasticity was confirmed by identifying calcium deposits in cultures that received osteogenic medium, and intracellular lipid accumulation in adipogenic cultures that received adipogenic medium. CONCLUSIONS: SCs collected from deciduous teeth show promising potential for application in tissue regeneration. Therefore, it is important that knowledge about the existence and characteristics of this source of stem cells be disseminated among dentists and that the technique, its limitations and possible indications are highlighted and discussed.

Gingival esthetics: an orthodontic and periodontal approach

INTRODUCTION: Currently, peoples esthetic requirements and expectations have increased substantially. Therefore, dentists have been seeking ways to provide excellent treatment results which, consequently, increasingly require a well organized transdisciplinary approach. The link between orthodontics and periodontics became evident from the moment professionals began to understand the biology of tooth movement. As regards smile esthetics, however, such cooperation is now essential. OBJECTIVE: To show clinically how and when orthodontists and periodontists should work jointly to enhance smile esthetics based on the display and harmony of the gingival contour.