Surgical and Orthodontic Treatment of Severely Intruded Permanent Incisors: A Case Report

Traumatic dental intrusion is a serious injury and results in significant damage to the periodontal ligament, dentin-pulp complex, and alveolar bone. This article presents a case of severe intrusion of the two upper permanent central incisors where the treatment option was the combination of the surgical and orthodontic technique. The difficulty of accessing the crowns of these teeth to bond the brackets was solved by lifting a full thickness flap. To disengage the teeth from the alveolus, a careful dislocation motion was performed. After suturing the flap, a removable orthodontic appliance was installed and an extrusive force was applied for 8 weeks. After 10 weeks, the endodontic treatment was performed and the crowns were restored. The 10-year clinical control showed normal mobility. Radiographically, minor losses of the cervical alveolar cortical bone and integrity of the periodontal ligament were observed.Keywords: Dental Trauma; Intrusive Luxation; Orthodontic Extrusio

Evaluation of an experimental rat model for comparative studies of bleaching agents

Dental materials in general are tested in different animal models prior to the clinical use in humans, except for bleaching agents. Objectives To evaluate an experimental rat model for comparative studies of bleaching agents, by investigating the influence of different concentrations and application times of H2O2 gel in the pulp tissue during in-office bleaching of rats’ vital teeth. Material and Methods The right and left maxillary molars of 50 Wistar rats were bleached with 20% and 35% H2O2 gels, respectively, for 5, 10, 15, 30, or 45 min (n=10 rats/group). Ten animals were untreated (control). The rats were killed after 2 or 30 days, and the maxillae were examined by light microscopy. Inflammation was evaluated through histomorphometric analysis with inflammatory cell count in the coronal and radicular thirds of the pulp. Fibroblasts were also counted. Scores were attributed to odontoblastic layer and vascular changes. Tertiary dentin area and pulp chamber central area were measured histomorphometrically. Data were compared by analysis of variance and Kruskal-Wallis test (

Evaluation of an experimental rat model for comparative studies of bleaching agents

ABSTRACT Dental materials, in general, are tested in different animal models prior to their clinical use in humans, except for bleaching agents. Objectives To evaluate an experimental rat model for comparative studies of bleaching agents by investigating the influence of different concentrations and application times of H2O2 gel in the pulp tissue during in-office bleaching of rats’ vital teeth. Material and methods The right and left maxillary molars of 50 Wistar rats were bleached with 20% and 35% H2O2 gels, respectively, for 5, 10, 15, 30, or 45 min (n=10 rats/group). Ten animals (control) were untreated. The rats were killed after 2 or 30 days, and the maxillae were examined by light microscopy. Inflammation was evaluated by histomorphometric analysis with inflammatory cell counting in the coronal and radicular thirds of the pulp. The counting of fibroblasts was also performed. Scores were attributed to the odontoblastic layer and to vascular changes. The tertiary dentin area and the pulp chamber central area were histomorphometrically measured. Data were compared by the analysis of variance and the Kruskal-Wallis test (

Neurosensory analysis of tooth sensitivity during at-home dental bleaching: a randomized clinical trial

Objective: The objective of this study was to evaluate dental sensitivity using visual analogue scale, a Computerized Visual Analogue Scale (CoVAS) and a neurosensory analyzer (TSA II) during at-home bleaching with 10% carbamide peroxide, with and without potassium oxalate. Materials and Methods:Power Bleaching 10% containing potassium oxalate was used on one maxillary hemi-arch of the 25 volunteers, and Opalescence 10% was used on the opposite hemi-arch. Bleaching agents were used daily for 3 weeks. Analysis was performed before treatment, 24 hours later, 7, 14, and 21 days after the start of the treatment, and 7 days after its conclusion. The spontaneous tooth sensitivity was evaluated using the visual analogue scale and the sensitivity caused by a continuous 0°C stimulus was analyzed using CoVAS. The cold sensation threshold was also analyzed using the TSA II. The temperatures obtained were statistically analyzed using ANOVA and Tukey's test (α=5%). Results: The data obtained with the other methods were also analyzed. 24 hours, 7 and 14 days before the beginning of the treatment, over 20% of the teeth presented spontaneous sensitivity, the normal condition was restored after the end of the treatment. Regarding the cold sensation temperatures, both products sensitized the teeth (p<0.05) and no differences were detected between the products in each period (p>0.05). In addition, when they were compared using CoVAS, Power Bleaching caused the highest levels of sensitivity in all study periods, with the exception of the 14th day of treatment. Conclusion: We concluded that the bleaching treatment sensitized the teeth and the product with potassium oxalate was not able to modulate tooth sensitivity

Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

Inter-relação do comprimento dos prolongamentos resinosos (tags) e da espessura da camada híbrida de adesão, com a resistência de união de sistemas adesivos ao tecido dentinário

O objetivo deste estudo foi analisar a correlação da espessura da camada híbrida de adesão e do comprimento dos prolongamentos resinosos (tags), com a resistência de união em tecido dentinário hígido, de um sistema adesivo convencional e de outro autocondicionante. Após a realização “in vivo” dos procedimentos restauradores, os dentes foram extraídos e seccionados no sentido mésio/distal. Em uma secção dental foi realizada a análise microscópica dos prolongamentos resinosos e da camada híbrida de adesão. Para tanto, os espécimes foram descalcificados, incluídos em parafina e cortados a uma espessura de 6 μm. Os cortes foram corados pelo método Brown e Brenn, para posterior análise e mensuração em microscópio óptico comum Axiophot Zeiss em 1000× (Carl Zeiss Company - DSM-940 A, Oberkochen, Baden- Württemberg, Germany). O remanescente dental foi acoplado à cortadeira metalográfica ISOMET 1000 (Buehler, Lake Bluff, IL, USA), de forma a permitir a realização de secções transversais, destinados ao teste de microtração (Instron modelo 4411 - Instron Inc., Canton, MA, EUA), sendo tracionados a 0,5 mm/min até sua ruptura. A superfície fraturada foi classificada segundo o padrão de fratura após análise sob lupa estereoscópica Stemi SV 11 (Carl Zeiss Company - DSM-940 A, Oberkochen, Baden-Württemberg, Germany) em aumento de 40×. Os valores obtidos no teste de microtração, na análise dos tags e da camada híbrida correspondentes a cada espécime e grupo de estudo, foram submetidos à análise estatística, com a realização do teste de Correlação de Pearson, não sendo verificada correlação entre os valores de resistência de união e a espessura da camada híbrida e comprimento dos tags resinosos em nenhum dos sistemas adesivos estudados.The purpose of this study was to evaluate the possibility of the correlation between the hybrid layer thickness, the resin tag length, and the resin bond strength of a conventional and a self-etching adhesive system into sound dentin tissue. After “in vivo” restorative procedures were performed, each specimen was extracted and sectioned in a mesiodistal direction. One of the dental sections was then analyzed on a light microscope where the hybrid layer thickness and resin tag length were measured. For this experiment, the specimens were decalcified, embedded in paraffin and serially sectioned at a thickness of 6 μm. The sections were subsequently stained using Brown and Brenn stain for posterior analysis and for the measurement of the hybrid layer thickness and the resin tag length on a Zeiss Axiophot light microscope at 1000× magnification (Carl Zeiss Company - DSM-940 A, Oberkochen, Baden- Württemberg, Germany). The other section was mounted onto a metallographic cutter ISOMET 1000 (Buehler, Lake Bluff, IL, USA) and was sectioned. A microtensile test was subsequently performed (Instron modelo 4411 - Instron Inc., Canton, MA, USA) with a crosshead speed of 0.5 mm/min. The fractured surfaces were analyzed and the fracture pattern was characterized using a stereoscopic magnifying glass Stemi SV 11 at a 40× magnification (Carl Zeiss Company - DSM-940 A, Oberkochen, Baden- Württemberg, Germany). The results were subjected to Pearson Correlation Test and verified that the hybrid layer thickness and the resin tag length did not correlate with the bond strength of the adhesives systems

Teste sensorial quantitativo no estudo da sensibilidade dentária decorrente de tratamentos clareadores

Depois de reconhecido como uma terapia esteticamente eficaz, o clareamento dental tem sido comumente procurado pela maioria dos pacientes na busca por um sorriso mais harmonioso e agradável. No entanto, o surgimento da sensibilidade dentária em decorrência do uso de peróxidos faz com que muito pacientes tornem-se insatisfeitos com o tratamento clareador. Neste contexto, estudos relacionados a essa sintomatologia são frequentes, porém, baseados em metodologias limitadas e imprecisas. Por isso, torna-se necessário empregar um método recente no campo odontológico a fim de enriquecer cientificamente as análises de sensibilidade dentária. Objetivos: Assim, o presente estudo objetivou analisar e quantificar a ocorrência de sensibilidade dentária por meio do Teste Sensorial Quantitativo (QST) com a utilização de um equipamento de análise neurosensorial em diferentes momentos do tratamento clareador e mesmo após o uso de dessensibilizantes. Além disso, relacionar o limiar de sensação dos pacientes com tal ocorrência para que se estabeleça um protocolo de indicação individual adequado. Materiais e Métodos: Inicialmente, sessenta voluntários foram divididos em 4 grupos de acordo com o limiar de sensação da pele (baixo - GI e GIII e alto - GII e GIV), classificado por meio do QST, e o tratamento clareador (peróxido de hidrogênio - GI e GII e placebo - GIII e GIV). A sensibilidade dental mensurada por meio do QST, em 10 tempos de estudo. Como estudo complementar, foi realizada a segunda etapa desta pesquisa, onde os dez pacientes restantes receberam o tratamento clareador com peróxido de hidrogênio a 35% (Whiteness HP Maxx) e após a sessão clareadora foi realizada a aplicação de um dessensibilizante tópico no hemiarco esquerdo da maxila. No hemiarco direito foi aplicada uma solução salina a temperatura ambiente (controle). O QST foi realizado...After being considered as an esthetically efficient technique, dental bleaching has been frequently sought by patients that look forward to a harmonious and pleasant smile. Nevertheless, dental sensitivity due to the use of peroxides makes patients become very unsatisfied with the bleaching treatment. In this context, studies related to this issue are very common, but based on limited and inaccurate methodologies. Therefore, we improved a recent method in dentistry in order to contribute to the enrichment of these scientific analyses. Objectives: Hence, the present study aimed to perform a Quantitative Sensory Testing (QST), using a neurosensory analyzer to verify and quantify the occurrence of dental sensitivity, in different periods of evaluation, during bleaching treatment and after the use of a desensitizer agent. Additionally, we related the patients' sensation threshold with this occurrence in order to establish an appropriate personal protocol statement. Materials and Methods: Seventy volunteers were criteriously selected and sixty from them were divided into 4 study groups according to the skin cold sensation threshold (low - GI and GIII and high - GII and GIV), obtained using QST, and the bleaching treatment (hydrogen peroxide - GI and GII and placebo - GIII e GIV). After the classification according to the skin cold sensation threshold, bleaching treatment was performed and dental cold sensation threshold was measured using QST in 10 different times. As a complementary study, we conducted the second part of this research. Ten patients underwent bleaching treatment using 35% hydrogen peroxide (Whiteness HP Maxx). After the bleaching session, a topical desensitizer was applied to the teeth of the left maxillary hemi-arch. A saline solution at ...Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP