Orthognathic surgery in a patient with von Willebrand disease: case report

Aim: This study aims to report the perioperative management of a patient with von Willebrand disease (vWd) who underwent orthognathic surgery. The report follows the guidelines of the Case Report Guidelines (CARE) and focuses on the steps taken to prevent bleeding during the surgical procedure. Methods: A 39-year-old female patient with skeletal Class III was treated with maxillary advancement and mandibular setback. Despite normal test results for ristocetin cofactor activity, measures were taken to prevent bleeding, including atraumatic surgical techniques, use of antifibrinolytic medication, induced hypotension during anesthesia, and preparation of blood products for transfusion during trans and postoperative periods if needed. In the end, these measures were not required. Results: The patient did not experience any bleeding during the surgical procedure or postoperative period, demonstrating the effectiveness of the measures taken to manage their blood dyscrasia. Two years after the surgery, the patient had satisfactory aesthetic and functional results and no evidence of relapse. Conclusion: Thus, this case report demonstrates that vWd does not prevent largescale oral and maxillofacial surgeries such as orthognathic surgery as long as proper precautions are taken pre-, intraand postoperatively

Avaliação do efeito da termociclagem na estabilidade de cor e rugosidade superficial de duas resinas compostas comerciais / Evaluation of thermocycling effect on color stability and surface roughness of two commercial resin composite

Objetivo: Avaliar o efeito do envelhecimento térmico por termociclagem na estabilidade de cor e rugosidade superficial de duas resinas compostas, avaliar grau de conversão (GC), sorção (SO), solubilidade (SL) e microdureza. Material e método: Foram confeccionados 10 espécimes (6 mm x 1 mm) para cada resina: Filtek Z350 XT (Z350XT) e Estelite Sigma Quick (ES). Foram avaliados: GC, utilizando um espectrofotômetro no infravermelho, SO e SL. A avaliação da microdureza Vickers (MV) e densidade de ligações cruzadas foi realizada antes e após a imersão em etanol por 24 h. A rugosidade superficial e a estabilidade de cor (CIEDE2000) foram avaliadas antes e após envelhecimento térmico por 2000 ciclos, alternando 30 s a 5°, 37° e 55° C. A estabilidade de cor e translucidez foram avaliadas com um espectrofotômetro. Os dados foram submetidos ao teste t (α=0,05). Resultados: ES apresentou resultados de GC maiores (62,5% ± 3,7) que Z350XT (48,7% ± 6,9) (p=0,004). Ambas resinas apresentaram resultados de SO e SL similares. A MV final da ES diminuiu 13% com relação a inicial (p=0,115). Z350XT apresentou diminuição de 17% (p=0,004). ES apresentou aumento de 115% na rugosidade superficial após a termociclagem (p=0,001), enquanto a Z350XT apresentou diminuição de 35% (p=0,299). ES apresentou menor alteração de cor (0,280 ± 0,093), quando comparada a Z350XT (0,549 ± 0,183). A translucidez foi similar para ambos materiais (ES=30,80; Z350XT=30,35). Conclusão: A termociclagem influenciou na alteração de cor e rugosidade superficial das resinas compostas, demonstrando que podem ser alteradas pela degradação na matriz polimérica.

Objective: To evaluate the thermocycling effect on color stability and surface roughness of two resin composites and also evaluate the degree of conversion (GC), sorption (SO), solubility (SL) and microhardness. Material and method: 10 specimens (6 mm x 1 mm) were made for each resin: Filtek Z350 XT (Z350XT) and Estelite Sigma Quick (ES). The following were evaluated: GC, using an infrared spectroscopy, SO and SL. Vickers microhardness (MV) and cross-link density evaluation was performed before and after immersion in ethanol for 24 hours. Surface roughness and color stability (CIEDE2000) were evaluated before and after thermal aging for 2000 cycles, alternating between 30 s at 5°, 37° and 55° C. Color stability and translucency were assessed with a spectrophotometer. Data were submitted to t test (α= 0.05). Results: ES presented higher GC results (62.5% ± 3.7) than Z350XT (48.7% ± 6.9) (p= 0.004). Both resins showed similar SO and SL results. The final MV of ES decreased 13% in relation to the initial (p= 0.115). Z350XT decreased by 17% (p= 0.004). ES showed a 115% increase in surface roughness after thermocycling (p= 0.001), while the Z350XT showed a 35% decrease (p= 0.299). ES showed less color change (0.280 ± 0.093) when compared to Z350XT (0.549 ± 0.183). The translucency was similar for both materials (ES= 30.80; Z350XT= 30.35). Conclusion: Thermocycling influenced the change in color stability and surface roughness of composite resins, demonstrating that they may be altered by degradation in the polymer matrix.

Long-term bonding efficacy of adhesives containing benzodioxioles as alternative co-initiators

Abstract This study evaluated the three-year lifespan of the bond to dentin of experimental self-etch adhesives containing benzodioxole derivatives - 1,3-benzodioxole (BDO) and piperonyl alcohol (PA) - as co-initiator alternative to amines. Adhesive resins were formulated using Bis-GMA, TEGDMA, HEMA, camphorquinone and different co-initiators: BDO, PA or ethyl 4-dimethylamino benzoate (EDAB - amine). An experimental self-etch primer was used to complete the two-step, self-etch adhesive system. Clearfil SE Bond (CSE) was used as commercial reference. Bond strength to human dentin was assessed by microtensile bond strength (µTBS) test, and failure mode was classified. Morphology of the dentin bonding interface was assessed via scanning electron microscopy (SEM). Irrespective of the dental adhesives evaluated, µTBS was higher after 24 hours compared with that after 1.5 and 3 years (p ≤ 0.001). However, adhesives with BDO and PA as co-initiators showed significantly higher bond strength than the bonding resin with EDAB (p ≤ 0.002), independent of the time evaluated. The commercial adhesive CSE showed similar bond strength compared with the other groups (p ≥ 0.05). Mixed failures were mainly observed after 24 hours, while adhesive failures were more frequently observed after 1.5 and 3 years. No notable differences in homogeneity and continuity along the bonded interfaces were detected among the materials in the SEM analysis. In conclusion, benzodioxole derivatives are feasible alternative co-initiators to tertiary amine in camphorquinone-based self-etching dental adhesive formulations.

Adhesion strategy and early bond strengths of glass-fiber posts luted into root canals

This study investigated the effect of coinitiator solutions and self-adhesive resin cement on the early retention of glass-fiber posts. Cylindrical glass-fiber posts were luted into 40 incisor roots with different adhesion strategies (n = 10): SB2, Single Bond 2 + conventional resin cement (RelyX ARC); AP, Scotchbond Multipurpose Plus (SBMP) activator + primer + ARC; APC, SBMP activator + primer + catalyst + ARC; and UNI, self-adhesive cement (RelyX Unicem). Pull-out bond strength results at 10 min after cementation showed APC > UNI > SB2 = AP (P < 0.05). The adhesion strategy significantly affected early bonding to root canals.