Comparing Torque Loss in Standard Implants and Short Implants with Increased Vertical Cantilever Abutments: an In Vitro Study / Comparação da perda de torque em implantes padrão e implantes curtos com pilares cantilever verticais aumentados (in vitro)

Objectives: With regard to the prevalence of abutment screw loosening (SL) and bone height reduction, particularly in the posterior regions of the jaws, as well as the contradictory issue of applying short implants instead of surgeries, along with all preparations associated with longer implants, the present study aimed to compare the amount of torque loss in short implants with increased vertical cantilever abutments and standard ones. Material and Methods: In this experimental study, a total number of 20 implants (MegaGen Implant Co., Ltd, South Korea) with 4.5 mm diameter including 10 short implants (7 mm) and 10 standard ones (10 mm) were utilized. Using a surveyor, fixtures were perpendicularly mounted in 13×34 mm resin for short implants and 19×34 mm resin for standard ones. The abutments of the same height but different cuff heights (2.5 mm for the standard implants and 5.5 mm for the short ones) were then tightened with 30 N.cm, via a digital torque meter. To compensate the settling effect, the abutment screw was re-tightened with 30 N.cm after 10 min. Upon applying 500,000 cycles at 75 N.cm and 1 Hz along the longitudinal axis on each sample, blind reverse torque value (RTV) was measured with a digital torque meter. The data were finally analyzed using Student's t-test. Results:Both groups experienced torque loss, but there was no statistically significant difference between the case and control groups in terms of abutment SL (p = 0451). Conclusion: Short implants seem to be a good mechanical alternative in emergencies with respect to torque loss and abutment SL. (AU)

Objetivos: Considerando a prevalência de afrouxamento de parafuso dos pilares, redução da altura óssea especialmente nas regiões posteriores, a questão contraditória da aplicação de implantes curtos em vez de cirurgias e todos os preparos associados a implantes mais longos, este estudo buscou comparar implantes curtos com pilares cantilever verticais aumentados e implantes padrão na quantidade de perda de torque. Material e métodos: Neste estudo experimental, foram utilizados 20 implantes (Megagen, Coreia do Sul) com diâmetro de 4,5 mm, incluindo 10 implantes curtos (7 mm) e 10 implantes padrão (10 mm). A fixação foi realizada perpendicularmente em uma resina 13 × 34 mm para implantes curtos e uma resina 19 × 34 mm para implantes padrão, usando um topógrafo. Os pilares da mesma altura, mas com diferentes comprimentos de manguito (2,5 mm para os implantes padrão e 5,5 mm para os implantes curtos) foram apertados com 30 N, utilizando um torquímetro digital. Para compensar o efeito de sedimentação, o parafuso do pilar foi reapertado com 30 N após 10 min. Depois de aplicar 500.000 ciclos a 75 N e 1 Hz ao longo do eixo longitudinal em cada amostra, o valor de torque reverso cego foi medido com um medidor de torque digital. Os dados foram analisados pelo teste t de Student. Resultados: Todos os grupos tiveram perda de torque, mas não houve diferença estatisticamente significativa entre os grupos caso e controle em termos de afrouxamento do parafuso do pilar (p = 0451). Conclusão: Os implantes curtos parecem ser uma boa alternativa mecânica em emergências em termos de perda de torque e afrouxamento do parafuso do pilar. (AU)

Material in Maxillofacial Prosthodontics - A Review

As there is an increase in the rate of oral cancer, the surge for the various maxillofacial materials is increasing as well. Materials used for rehabilitation of congenital or acquired defects of patients should fulfil the requirements such as function, longevity, and aesthetics. Defects of face which may be congenital or acquired makes the condition of the affected person very disastrous mentally, physically as well as emotionally. Patient wants facial rehabilitation for a healthy happy life. To provide rehabilitation of these patients, re-evaluation of materials used in the field of maxillofacial prosthesis seems essential. Maxillofacial material should best suit the ideal selection criteria to satisfy the functionality, biocompatibility, aesthetics as well as durability. While the new materials have exhibited many desirable properties, there are also many insufficiencies involved in it. This article presents a systemic review of the evolution, current trends, and future requirements in maxillofacial materials for ensuring psychological well-being.In the recent years, a dramatic increase in the demand for prosthetic rehabilitation of patients with facial defects is seen. Increasing awareness of cancer is resulting in earlier diagnosis and treatment. Unfortunately, many of the surgical techniques are extensive and thus leave large defects that compromise not only function and aesthetics, but also psychosocial status of the patient. These problems require prompt rehabilitation with surgery or prosthetics.1 However, surgical reconstruction is often contraindicated in the presence of large defects or in high-risk patients. Prosthesis offers the advantage of quick, reversible and medically uncomplicated rehabilitation. In addition, the restoration may be readily removed to allow evaluation of the health of the underlying tissues. Historically, many types of materials have been used. Wood, wax metals, vulcanite and many types of plastics have been used as rigid materials while flexible ones like gelatin glycerine mixtures, latex and elastic plastics have also found some usefulness.2Presently, materials used for the maxillofacial prosthesis are vinyl plastics, polyurethane, silicone rubber and acrylic types.

A real-world study of paritaprevir/ritonavir-ombitasvir combined with dasabuvir in the treatment of genotype 1b chronic hepatitis C / 中华肝脏病杂志

Objective@#To recognize the efficacy and safety of paritaprevir/ritonavir-ombitasvir combined with dasabuvir (OBV/PTV/RTV+DSV) in the treatment of genotype 1b chronic hepatitis C.@*Methods@#Patients with genotype 1b chronic hepatitis C who were admitted to the People's Hospital of Henan Province, Huashan Hospital of Shanghai and the Fifth Medical Center of the General Hospital of the People's Liberation Army of China between November 2017 to August 2018 were enlisted. All patients received OBV/PTV/RTV+DSV antiviral therapy. HCV RNA levels were measured at baseline, weeks 1, 2, 3, 4, 8, 12, and 24, then 12 weeks, and 24 weeks after completion of treatment; patients’ comorbidity, concomitant medications, and clinical adverse events were recorded.@*Results@#108 patients were enrolled in the study, with an average age of 49.1 years, 44 patients were male (40.8%), 96.3% (104/108) were newly diagnosed, and four patients had previous treatment history, of whom three were treated with IFN and one with IFN + DAA. Ninety-eight cases completed 12 weeks treatment and 89 cases were in follow up for 12 weeks, after discontinuation of the drug. Overall, 89 cases (100%) achieved SVR12.One patient treated with PR and DAA had HCV RNA level of 869175 IU/mL at 4 weeks of treatment, which was significantly higher than the baseline HCV RNA level (301776IU/ML), and was judged as failure of treatment; and follow-up was discontinued. Of all enrolled patients, 19 (17.6%) had underlying diseases and 15 (13.9%) had combined medications. During treatment, adverse events (AE) occurred in 11 patients (10.1%). The main adverse events were pruritus and elevated bilirubin.@*Conclusion@#Combined antiviral therapy (OBV/PTV/RTV+DSV) of 12 weeks are highly effective with good safety profile in the treatment of Chinese patients with genotype 1b chronic hepatitis C.