Cristina Braga Xavier

Comparative chemical study of MTA and portland cements

Portland cement has been analyzed and compared to mineral trioxide aggregate (MTA) because of their chemical similarity. The possibility of using this material as a less expensive alternative to MTA in dental practice should be considered. In view of this, the present study compared the components of a Portland cement (Votoran) to two commercial brands of MTA (Pro-Root and MTA-Angelus). Twelve specimens of each material were fabricated and examined by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) to obtain their percentage of chemical elements. The means of the chemical elements found in each material was compared by descriptive statistics. Bismuth was present only in MTA cements to provide radiopacity. In conclusion, the tested cements have similar components, which supports, as far as composition is concerned, the possible clinical use of Portland as an option to MTA.

Dentin penetrability evaluation of three different dyes in root-end cavities filled with mineral trioxide aggregate (MTA)

The purpose of this study was to evaluate the penetration of three dyes in MTA root-end fillings. In 30 single-rooted teeth, cavities for retrofilling were prepared with an ultrasound appliance and filled with MTA. The specimens were randomly assigned to three groups (n = 10) and immersed in the following solutions: 2% methylene blue (MET), 50% silver nitrate (NIT) and 0.2% rhodamine B (ROD). Two transversal slices (1 mm) of the retrofilling region were obtained and evaluated using the Image Tool 3.0 software to obtain a quantitative evaluation (in mm2) of the dye penetration around the retrofillings. Data were submitted to statistical analysis using Students t-test. The lowest degree of dye penetration was observed for the NIT group, in both slices (p < 0.05). Dye penetration was significantly larger in the ROD group when compared to the NIT group, in both slices (p < 0.05), and to the MET group, only in slice 1 (p < 0.05). Within the limitations of this study, it was concluded that the choice of dye could influence the penetration evaluation in root-end filling studies, and that the NIT had the lowest penetration capacity in the apical dentine.

CO2, Er: YAG and Nd:YAG lasers in endodontic surgery

Objectives: CO2, Er:YAG and Nd:YAG lasers have been used in endodontic surgery. This in vitro study evaluated 1% Rhodamine B dye penetration using computer-assisted morphometry (ImageTool Software®) of 108 endodontically treated human permanent canines. Material and methods: Teeth were divided into 9 groups according to the technique used: A: 90-degree apicoectomy with bur, root-end cavity preparation with ultrasound and filled with MTA; B: 90-degree apicoectomy with bur, root-end cavity prepared with ultrasound and filled with MTA, and treatment of apical surface with CO2 laser (1 W, CW/CW); C: 90-degree apicoectomy with bur, and treatment of apical surface with Nd:YAG laser (150 mJ, 10 Hz); D: 90-degree apicoectomy with bur, and treatment of apical surface with CO2 laser (1 W, CW/CW); E: apicoectomy with Er:YAG laser (400 mJ, 10 Hz), root-end cavity prepared with ultrasound and filled with MTA; F: apicoectomy with Er:YAG laser (400 mJ, 10 Hz) and treatment of apical surface with Nd:YAG laser (150 mJ, 10Hz); G: apicoectomy with CO2 laser (5W, CW/SP), root-end cavity prepared with ultrasound and filled with MTA; H: irradiation of apical end with CO2 laser (1 W, CW/CW); I: irradiation of apical end with Nd:YAG laser (150 mJ, 10 Hz). Results: Dye penetration was found in all specimens at different rates, the lowest penetration occurring in groups C (16.20%), B (17.24%) and F (17.84%). Conclusions: Groups B, C and F represent the best technical sequences to perform endodontic surgery.

Spontaneous Migration of Third Molar Following Displacement to Pterygomandibular Fossa

The accidental displacement of lower third molars or root fragments into fascial spaces is rare; when it does occur, the most affected anatomic sites are the submandibular and pterygomandibular spaces. Causes and possible complicaions are widely discussed in the literature. The position of he tooth directed toward the lingual or distal face, a thin ingual cortex, application of excessive force, inapproprite instruments, and inadequate examinations are factors hat may contribute to the occurrence of displacement. Injury to tissues, pain, swelling, lockjaw, and foreign body reaction are some of the related complications, along with the medical-legal implications. Thus, patient history and linical and imaging examinations must be rigorously evalated to establish the best planning of the surgery and void the occurrence of accidents and possible surgical omplications. The oral surgeon must be familiar with the treatment nstituted in these cases, because the surgeon is always esponsible for the resolution of the case, even when the urgeon was not the one who performed the extraction. his case report describes a lower third molar accidentally isplaced to the pterygomandibular space and discusses spects regarding the diagnosis and treatment of such acidents in light of the current literature.

Oral and maxillofacial rehabilitation of a patient suffering from intraosseous adenoid cystic carcinoma

O tratamento das neoplasias em regiao de cabeca e pescoco pode deixar sequelas que afetam a qualidade de vida do paciente durante e apos o tratamento. A comunicacao buconasosinusal decorrente da resseccao cirurgica parcial ou total do palato traz ao paciente alteracoes na funcao mastigatoria, estetica, fonetica e de degluticao o que pode levar a um isolamento social do individuo. Em vista disso, a atuacao do cirurgiao dentista junto a equipe multiprofissional de atendimento ao paciente oncologico se faz fundamental, podendo contribuir no diagnostico, auxiliar no manejo de complicacoes do tratamento quimioterapico/radioterapico, e na reabilitacao bucomaxilofacial, sendo esta uma alternativa para melhorar a qualidade de vida do paciente, pois visa restabelecer as funcoes alteradas em decorrencia do procedimento cirurgico. O presente estudo relata o caso de uma paciente portadora de carcinoma adenoide cistico na maxila submetida a maxilectomia parcial, deixando como sequela a comunicacao buconasosinusal. O acompanhamento odontologico foi realizado no Hospital Escola da Universidade Federal de Pelotas no pre-operatorio, durante e apos o tratamento. No momento a paciente esta reabilitada com uma protese obturadora em acompanhamento pela equipe de odontologia e pelo cirurgiao de cabeca e pescoco.

Therapeutic Approach to Pulp Canal Calcification as Sequelae of Dental Avulsion

Tooth avulsion represents the most complicated dental injury, and the classic treatment is tooth replantation. The most common sequelae are pulp canal calcification (PCC) and pulp necrosis. The presence of pulp necrosis after PCC is reported in up to 30% of the cases and is a challenge due to the difficulty of endodontic treatment. This case report describes the surgical treatment of a replanted tooth presenting PCC and periapical pathology eight years after the trauma. An endodontic surgery was performed to remove the apical granuloma, to prepare the apical root, and to seal the apical region with an endodontic cement. In a three-year follow-up, there was an absence of inflammatory signs and symptoms or apical lesion. This report shows the importance of close follow-up after dentoalveolar injuries. After the initial dental trauma and its consequences to pulpal tissues, the executed procedures allowed a favourable outcome.

Management of an uncomplicated crown fracture by reattaching the fractured fragment-Case report

Coronal fractures of the anterior teeth are common sequelae of traumatic dental injuries. Reattachment of fractured tooth fragments using dental adhesive techniques offers some advantages, including restoration of the function, esthetics, shape, texture, and brightness of the surface. The present report describes a clinical case of reattachment with a 4-year clinical and radiographic follow up in a permanent maxillary central incisor with an uncomplicated crown fracture. Fragment reattachment is a conservative procedure, preserving esthetics and functionality, and it can provide an immediate positive emotional response from the patient.

Preoperative evaluation of third molar root characteristics: Correlation between clinical and radiographic findings

Purpose: In this study, periapical and panoramic radiographic tests were compared to the clinical examination (after extraction, gold standard) to verify their accuracy in identifying number of roots, root morphology, and presence of root dilaceration in impacted third molars. Methods: In total, 98 third molars were extracted (50 maxillary, 48 mandibular). Three dental surgeons and one radiologist were calibrated to analyze the root characteristics before (radiography) and after extraction. Agreement between clinical and radiographic findings was analyzed with weighted kappa (κ) statistics. Correlation between radiographic and clinical data was assessed using Spearman correlation test. A 5% significance level was set for all analyses. Results: Upper teeth with single/fused roots and lower teeth with two roots were predominant. Higher agreement and correlation for number of roots and root morphology was observed for periapical (κ=0.258–0.612; R2=0.463–0.612; P<0.001) compared with panoramic exam (κ=0.164–0.365; R2=0.175–0.417; P<0.01), and for lower compared with upper teeth. For lower teeth, convergent/parallel roots were predominant in the clinical analysis, while divergent roots were predominant in the imaging tests. For root dilaceration, poor agreement (κ=0.199–0.273) and low correlation (R2=0.185–0.306) was observed for either radiographic examinations. Conclusion: The accuracy of radiographic examinations in identifying the root characteristics of impacted third molars was generally low. Compared with the panoramic test, periapical radiography had better agreement and higher correlation with the clinical findings for all root features.

Multidisciplinary approach in the immediate replantation of a maxillary central incisor - A six and a half year follow-up

This report proposes a discussion of the various peculiarities of a tooth 21 replantation in a 9-year-old patient and describes different treatment facets and a 6-year follow-up of the case. The splint was maintained for a 3-month period. After a 1΍ year therapy with calcium hydroxide to control inflammatory resorption, the final canal obturation was performed 18 months after trauma with mineral trioxide aggregate. Two years after replantation, the orthodontic treatment had been initiated and 5 years after avulsion, whitening of tooth 21 was also done. Clinical and radiographic follow-up at regular intervals revealed that the treated tooth was still functional, showing normal mobility, resorption stabilization, and normal appearance of the bone tissue and lamina dura, testifying the treatment has been so far successful. The possibility of submitting avulsed teeth to other dental treatments once, there is close professional monitoring by controlling the risks and benefits of each therapy, as well as the patient′s cooperation, extra-oral time, and storage media for transport to the dentist among other details is emphasized.

Utilização de ultra-som em cirurgia parendodôntica

O avanco tecnologico incrementou os indices de sucesso de procedimentos odontologicos. Em cirurgia parendodontica, retropontas ultra-sonicas proporcionam uma retrocavidade de qualidade superior e permitem uma apicectomia em 90 graus, removendo maior quantidade de tecido contaminado. Os autores realizaram uma revisao de literatura da tecnica in vitro e in vivo; procederam a analise de retrocavidades feitas com broca e retroponta ultra-sonica, com auxilio de macrofotografias digitais e Microscopia Eletronica de Varredura.