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Modeling liquids/resins have been used to build up resin composite (RC) restorations, although there is a lack of information regarding their effects on the color stability of the latter. Therefore, the purpose of the present study was to evaluate the effects of the presence of modeling liquid between layers of RC and the finishing/polishing state of the material on color change in specimens exposed to red wine staining over time. Specimens were prepared by placing four increments (±0.5 mm thick) of RC (Filtek™ Z350 XT, 3M ESPE) into molds; half of which were prepared by applying modeling liquid (Scotchbond™ Multi-Purpose™ Adhesive, SBMP, 3M ESPE) between the layers of RC, whereas the other half were prepared without SBMP (control). Light-activation was performed after application of the final RC layer using a light-emitting diode (Radii, SDI) curing unit with an irradiance of 900 mW/cm 2 for 20 s. Each group was divided according to the surface finishing protocol (n = 7): nothing (non-polished) or polishing with Sof-Lex™/diamond paste (polished). Initial colors of the specimens were evaluated with a digital spectrophotometer and the CIEL * a * b * color system. The specimens were stored in wine (37°C) for 12 months, and the color measurements were reassessed after 4, 6, and 12 months of storage. Scanning electron microscopy (SEM) analysis was performed at the end. Data were analyzed using ANOVA and Tukey's test (α = 5%). The presence of SBMP resulted in lower overall color change of the RC as compared with the control. The non-polished specimens exhibited a significantly higher color change than the polished specimens. SEM images corroborated the previous findings. In summary, the use of modeling liquid between layers of RC shows potential for application to reduce or delay the staining process of RC over time. Moreover, polishing is essential to provide increased color stability of the RC restoration.

ObjectiveTo evaluate the effect of restorative strategy (fiber post vs cast post and core), coronal height (0 mm vs 2 mm) and thickness (higher than 1 mm vs lower than 1 mm) on survival rate, fracture resistance and stress distribution.Material and MethodsSeventy-two bovine teeth were cleaned and allocated in six groups (n = 12). Twenty-four teeth were sectioned at 13 mm length (no remaining coronal structure) and forty-eight were sectioned at 15 mm (2 mm remaining coronal structure). Half of the forty-eight had remaining coronal thickness lower than 1 mm and the other half had thickness higher than 1 mm. All root canals were prepared at 10 mm (luting length), fiber posts were cemented in thirty-six specimens and cast post and core in other thirty-six. All teeth were restored with metallic crowns. Specimens were submitted to 1.5 million cycles (100 N, 45°, 10 Hz at 2 mm below incisal edge) and evaluated at each 500,000 cycles to detect failures. Specimens that survived were submitted to load to fracture test. Bidimensional (Rhinoceros® 4.0) models were obteined survival data submitted to Kaplan-Meier (α=0.05) analysis and load to fracture values submitted to ANOVA and Tukey tests (α=0.05).ResultsGroups without remaining coronal structure showed survival rates lower than other groups (p=0.001). ANOVA showed higher values of load to fracture for groups with coronal thickness higher than 1 mm (p=0.0043). Finite element analysis showed better stress distribution in groups with remaining coronal structure and restored with fiber post.ConclusionSpecimens without remaining coronal structure have lower survival rates. Specimens with remaining structure lower than 1 mm and without coronal structure support the same load to fracture value independently of the restorative strategy.

Resin cements are often used for single crown cementation due to their physical properties. Self-adhesive resin cements gained widespread due to their simplified technique compared to regular resin cement. However, there is lacking clinical evidence about the long-term behavior of this material. The aim of this prospective clinical trial was to assess the survival rates of metal-ceramic crowns cemented with self-adhesive resin cement up to six years. One hundred and twenty-nine subjects received 152 metal-ceramic crowns. The cementation procedures were standardized and performed by previously trained operators. The crowns were assessed as to primary outcome (debonding) and FDI criteria. Statistical analysis was performed using Kaplan-Meier statistics and descriptive analysis. Three failures occurred (debonding), resulting in a 97.6% survival rate. FDI criteria assessment resulted in scores 1 and 2 (acceptable clinical evaluation) for all surviving crowns. The use of self-adhesive resin cement is a feasible alternative for metal-ceramic crowns cementation, achieving high and adequate survival rates.

A articulação temporomandibular (ATM) possibilita a mastigação, deglutição e a fonética, faz parte do sistema estomatognático, e é capaz de múltiplos movimentos. A DTM (disfunção temporomandibular) representa certas condições musculares e articulares na região crânio orofacial que podem causar problemas nos músculos da mastigação e na ATM e suas estruturas associadas, sendo a cefaleia e a dor orofacial alguns dos principais sintomas relatados pelos pacientes. Objetivo: analisar a relação da DTM à dor orofacial e cefaleia através de uma revisão narrativa. Métodos: para a realização deste estudo, foram feitas buscas nas bases de dados Scielo e Pubmed, utilizando as palavras chave: Dor Orofacial, Disfunção Temporomandibular, Articulação Temporomandibular, Dor de Cabeça e Cefaleia. Conclusão: a partir dos artigos analisados na presente revisão foi possível concluir que existe relação entre dor na região orofacial e cefaleia com a DTM, porém ainda não é claro o mecanismo dessa correlação, sendo necessários mais estudos para elucidar esse quadro clínico.

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Background: A cracked tooth may be challenging for dentists because it may present with varied intensities, may be asymptomatic, and may still not be clinically visible. The transilumination method can facilitate diagnosis and ensure appropriate treatment in such cases. The aim of the present article was to report a clinical case of an anterior cracked tooth with a nonesthetic class IV restoration. Clinical considerations: A 22-year-old male patient with chief complaint of esthetics of upper front tooth reported a history of dental trauma. Transilumination with a dental curing light unit was used to examine the region. The tooth 11 was diagnosed with several cracks and a nonesthetic class IV restoration. For repair, the universal adhesive system Scotchbond Universal was applied without previous acid etching, followed by the application of Filtek Z350 of color type B2 (for body) above the old restoration, taking care to slightly overlap the fracture line with the composite and to not extend the composite until the incisal margin. Subsequently, a thin layer of Filtek Z350 of color type B2 (for enamel) was applied over the bevel until the incisal margin, and the tooth shape was carved. Conclusion: This case report demonstrates simplifi ed diagnosis of an anterior cracked tooth with transilumination; following repair, the esthetic quality of the restoration was considered satisfactory and approved by the patient.