João Caramês

Clinical efficacy of electronic apex locators: systematic review.

INTRODUCTION Apical constriction has been proposed as the most appropriate apical limit for the endodontic working length. Despite being the most used, some limitations are attributed to the radiographic method of working length determination. It lacks precision because it is based on the average position of the apical constriction. The electronic apex locators have been presented as an alternative to the odontometry performed by radiography. These devices detect the transition of the pulp to the periodontal tissue, which is anatomically very close to the apical constriction and may perform with improved accuracy. METHODS A systematic review was performed to compare the radiographic and electronic methods. Clinical studies that compared both methods were searched for on 7 electronic databases, a manual search was performed on the bibliography of articles collected on the electronic databases, and the authors were contacted to ask for references of more research not detected on the electronic and manual search. RESULTS Twenty-one articles were selected. The majority were comparative or evaluation studies, and very few clinical studies comparing both methods are available. Several methodological limitations are present on the collected articles and debated in this review. CONCLUSIONS Although the available scientific evidence base is short and at considerable risk of bias, it is still possible to conclude that the apical locator reduces the patient radiation exposure and also that the electronic method may perform better on the working length determination. At least one radiographic control should be performed to detect possible errors of the electronic devices.

An Alternative Sinus Floor Elevation Procedure: Trephine Osteotomy

Today, the sinus floor elevation procedure is not only being used on a routine basis, but clinicians are reporting high success rates. The sinus floor graft has become an important option in the treatment of the edentulous posterior maxilla, where vertical bone height is less than ideal. A review of maxillary sinus floor elevation as an integral part of restoring the posterior maxillary is discussed. The related anatomy of the area and current osteotomy techniques are reviewed. This article describes a trephine osteotomy, which is an alternative technique to the existing lateral antrostomy approach currently being used.

Postura e Disfunção Temporo-Mandibular, Controvérsias Actuais

Resumo Nos ultimos anos, varios autores tem estudado a relacao entre Disfuncao Temporomandibular (DTM) e Desordens Cervico-espinhais (DCE), com o objectivo de determinar se existe influencia reciproca entre as estruturas do sistema estomatognatico e a cadeia postural. A diversidade de opinioes sobre este tema tem dificultado a obtencao de consensos, que possam orientar o Medico Dentista na abordagem clinica do paciente com Disfuncao. Objectivo Averiguar se existe, na actualidade, consenso entre os varios autores sobre a relacao entre a DTM e as DCE. Materiais e Metodos Foram consultados artigos disponiveis no banco de dados PubMed bem como alguns livros de areas relacionadas. Resultados A maioria dos estudos demonstra que os disturbios musculares e posturais sao mais frequentes em pacientes com DTM e estabelece algum tipo de correlacao entre o tipo de oclusao, a existencia de sinais e sintomas de DTM, as dimensoes craniofaciais, a anteriorizacao da cabeca (FHP) e o desequilibrio postural, embora nem sempre consigam explicar o mecanismo subjacente, ou mesmo atribuir causalidade entre os dois tipos de disfuncao. Conclusoes Na ausencia de fortes indicios ha que tomar decisoes baseando-nos nas evidencias disponiveis, o que se traduz na necessidade de uma abordagem biomecânica glo-bal que inclui o corpo como um todo, no exame e elaboracao do plano de tratamento do paciente com desordens temporomandibulares. A coordenacao entre especialistas das varias areas, nomeadamente da Medicina Dentaria e Fisiatria deve ser procurada, de forma a proporcionar o melhor tratamento aos pacientes com disfuncao.

Prevalence of C-shaped mandibular molars in the Portuguese population evaluated by cone-beam computed tomography.

Objective: The purpose of this study was to evaluate the prevalence of first and second C-shaped mandibular molars in a Western European population of Portuguese Caucasians. Materials and Methods: Patients having both routine panoramic radiograph and presurgical cone-beam computed tomography (CBCT) exams were selected. The CBCT examination was performed at five different axial levels and the mandibular molars were classified as C-shape according to the Fan criteria. Differences between genders, age groups, left and right side, type of tooth, and root concavity side were determined. The molars were classified as nonfused roots (NFRI–II), FRI–III, or single root with single canal (SS) groups, using the panoramic radiograph. The prevalence of C-shaped anatomy was calculated to each group. Results: A total of 1783 teeth (695 first molars and 1088 second molars) from 792 patients were included in the study. The prevalence of C-shaped configurations was 0.6% and 8.5% to mandibular first and second molars, respectively. The differences between gender, teeth, and root concavity direction were considered statistically significant (P < 0.05). The FR had a significantly higher rate of C-shapes when compared to NFR (P < 0.05). Intrarater reliability was 93.6%. Conclusions: The FR radiographic appearance may be considered a predictor of this anatomy. Second mandibular molars and females had a higher incidence ratio. Apparently, the mandibular C-shaped anatomy is more common in the population of this study than that has been previously reported for the European population.

Unusual growth of a nasopalatine cyst

Abstract The main goal of this work is to report the aggressive potential of the nasopalatine cyst (NPC) in the pre-maxilla, when theres invasion of the medullar spaces. Bone resorption, soft tissue swelling, and displaced root remnants were clinical and radiological signs of this long-term asymptomatic and slow progression lesion. Histopathology showed a mixture of stratified non-queratinized with pseudostratified epithelium compatible with NPC. Careful should be made when screening patients since this entity can easily go unnoticed and the slow painless progression can lead to severe hard tissue defects.

Prognosis of Indirect Composite Resin Cuspal Coverage on Endodontically Treated Premolars and Molars: An In Vivo Prospective Study

PURPOSE This prospective clinical study evaluated the success rate of indirect composite resin cuspal coverage on endodontically treated molars and premolars and the survival rate of the restored teeth. MATERIALS AND METHODS One hundred fifty endodontically treated teeth were restored with total resin cuspal coverage and randomly selected for the study. Patients were recalled after 2 to 5 years for clinical evaluation. Data were subjected to standard tests of statistical correlations using Spearman test. RESULTS Out of the 150 teeth, 84 were molars and 66 were premolars. Of these teeth, 58.7% had mesio-occlusal-distal (MOD) cavities, 20.7% had mesio-occlusal (MO), and 20.7% had occlusal-distal (OD). A build-up procedure was performed in 51.3% of the teeth, and buccal veneer composite resins were placed at the margins of 96.7% of the teeth. Out of the 150 teeth, 30 (20%) presented margin discoloration, 3 teeth (2%) had restoration reparable fractures, 2 teeth (1.3%) had restoration irreparable fractures, and 1 tooth (0.7%) exhibited secondary recurrent caries. The opposing arch that occluded with the treated teeth presented 58% natural teeth (no restoration material), 26.7% ceramic crowns, and 15.3% implant-supported ceramic crowns. Statistically significant differences (p = 0.018) between irreparable restoration fractures and the type of support material present in the opposing arch were found. CONCLUSIONS In a period of up to 5 years, the resin cuspal coverage of endodontic treated teeth had a success rate of 96%, while the tooth survival rate was 100%. The type of support material on the opposing arch may influence the longevity of the restoration of endodontically treated teeth.

Ceramic-Veneered Zirconia Frameworks in Full-Arch Implant Rehabilitations: A 6-Month to 5-Year Retrospective Cohort Study.

PURPOSE This was a retrospective cohort study designed to evaluate the clinical performance of ceramic-veneered zirconia frameworks. MATERIALS AND METHODS Patients were recruited according to defined inclusion criteria. All patients were checked every 4 months from the time of definitive rehabilitation. At the end of 2013, all patients were rescheduled and rechecked for study purposes. The restorative procedures assessment was performed by previously established methods. The primary outcomes were the survival and success rates of the prosthesis. Descriptive statistics were used for the patients demographics, implant distribution, and occurrence of complications. To study the survival and success of the prostheses, a Cox Regression analysis was used with a model constructed in a forward conditional stepwise mode. Predictive variables were included in the model, and adjusted survival curves were obtained for each outcome. RESULTS From 2008 to 2013, 75 patients were rehabilitated with 92 implant-supported, screw-retained, full-arch ceramic-veneered zirconia framework rehabilitations. The range of follow-up was between 6 months and 5 years. From the 92 full implant-supported screw-retained full-arch rehabilitations, Cox regression analysis indicated that within a 5-year time frame, the probability of framework fracture, major chipping, minor chipping, or any of the former combined to occur was 17.6%, 46.5%, 69.2%, and 90.5%, respectively. CONCLUSION Results suggest zirconia as a suitable material for framework structure in implant-supported, full-arch rehabilitations. However, it experiences a high incidence of technical complications, mainly due to ceramic chipping. Further clinical studies should aim to ascertain the effects of clinical features and manufacturing procedures on the survival rates of these prostheses.

Differences on the Root and Root Canal Morphologies between Asian and White Ethnic Groups Analyzed by Cone-beam Computed Tomography

Introduction: Populations from different geographic regions and ethnic backgrounds may present differences in dental morphology. The aim of this study was to compare the differences in root and root canal configurations on Asian and white subpopulations using cone‐beam computed tomographic imaging. Methods: Information from Asian and white patients was retrieved from 2 cone‐beam computed tomographic imaging databases in China and Western Europe. Two calibrated observers collected data regarding the number of roots and Vertucci root canal system configuration for all groups of teeth. A total of 15,655 teeth were analyzed. The z test for independent groups was used to analyze differences between the groups. The significance level was considered at a P value < .05. Reliability tests were performed between observers. Results: Differences were noted in the number of roots per tooth in 6 groups of teeth. The Asian group showed a higher prevalence of single‐root configurations in maxillary first premolars (83.2%) and mandibular second molars (45.4%) when compared with whites with 48.7% and 14.3%, respectively. Moreover, 3‐rooted configurations in mandibular first molars were more common in Asians (25.9%) compared with whites (2.6%). Seventeen of the 20 analyzed roots had a higher prevalence of Vertucci type I configuration in Asians. Maxillary first molars with second mesiobuccal root canals were more commonly found in whites than in Asians (71.3% and 58.4%, respectively). A similar situation was found in maxillary second molars. Conclusions: The Asian ethnic group presented a higher prevalence of Vertucci type I configuration, whereas the white group displayed a higher number of multiple root canal system morphologies. A clinician should be aware of these differences when treating patients from these ethnic groups.

Very Large Inflammatory Odontogenic Cyst with Origin on a Single Long Time Traumatized Lower Incisor.

One of the consequences of traumatic injuries is the chance of aseptic pulp necrosis to occur which in time may became infected and give origin to periapical pathosis. Although the apical granulomas and cysts are a common condition, there appearance as an extremely large radiolucent image is a rare finding. Differential diagnosis with other radiographic-like pathologies, such as keratocystic odontogenic tumour or unicystic ameloblastoma, is mandatory. The purpose of this paper is to report a very large radicular cyst caused by a single mandibular incisor traumatized long back, in a 60-year-old male. Medical and clinical histories were obtained, radiographic and cone beam CT examinations performed and an initial incisional biopsy was done. The final decision was to perform a surgical enucleation of a lesion, 51.4 mm in length. The enucleated tissue biopsy analysis was able to render the diagnosis as an inflammatory odontogenic cyst. A 2 year follow-up showed complete bone recovery.

Bioactivity of novel functionally structured titanium-ceramic composites in contact with human osteoblasts: Bioactivity of functionally structured titanium-ceramic composites

The aim of this study was to analyze the osteogenic cell behavior on the surface of novel functionally graded titanium-based composites containing bioactive ceramics. Titanium grade V discs (8 × 3 mm) embedding gradual content of hydroxyapatite (TiAlV-HA) or beta-tricalcium phosphate (TiAlV-βTCP) were produced by hot-pressing technique. Titanium-ceramic composite discs and Ti grade V (control group) were placed in contact with human osteoblast culture assays. The morphology and adhesion of osteoblasts were inspected by field emission guns scanning electron microscopy (FEGSEM) while cell viability was assessed by fluorometric method. Alkaline phosphatase (ALP) activity and fluorescent microscopic analyses were used to evaluate mineralization on the test and control discs. FEGSEM images showed cells adhered to Ti6Al4V-ceramic and Ti6Al4V surfaces over a period of 24 h, and therefore, an intense proliferation of osteoblasts and spreading cells was noticed for 7 days. Cell viability increased with time on all the surfaces although TiAlV-βTCP revealed significant higher percentage of cell viability than that recorded for TiAlV-HA (p < 0.01). TiAlV-βTCP also showed the highest hydrophilic character. ALP levels increased on the Ti6Al4V-ceramic surfaces when compared to the control group. Also, a qualitative analysis of mineralization evidenced an increase in mineral content on TiAlV-HA or TiAlV-βTCP groups. Novel functionally graded composites based on Ti grade V and hydroxyapatite or βTCP showed a higher bioactivity in presence of osteoblasts than that recorded on Ti grade V. Also, such functionally graded materials can prevent risks of failures by detachment of bioactive ceramic materials during implant placement.