Modified radical mastectomy: A pilot clinical trial comparing the use of conventional electric scalpel and harmonic scalpel

Background: The aim of this study was to compare the rates of local postoperative complications among women undergoing modified radical mastectomy with an electric scalpel (ES) or a harmonic scalpel (HS). It is thought that HS use has less postoperative complications, mainly seroma formation. Methods: This study was a prospective non-randomised clinical trial (NCT01391988) among consecutive patients, performed in parallel. Patients underwent modified radical mastectomy using an HS or ES. We analysed the following operative variables: time, blood loss and seroma volume drainage. Postoperative complications, including seroma, flap necrosis, haematoma and infection were evaluated on the 7th and 14th days. Results: Forty-six patients underwent a MRM with ES and 49 with HS; no differences were observed between the groups. The rate of local complications was 29% in the HS group and 52% in the ES group (p=0.024). The rates of seroma (16.3% versus 28.3%; p=0.161), necrosis (4.1% vs. 21.7%; p=0.013; OR=0.15), haematoma (2.0% vs. 8.7%; p=0.195) and infection (2.0% vs. 6.5%; p=0.351) were lower in the HS group. Adding the findings of all comparative studies using HSs in MRM to the seroma rates in the current study, the seroma rate, expressed as a categorical variable, did not decrease with HS. Seroma was present in 60/219 cases using an HS and in 69/239 cases utilising an ES (p=0.72). Based on a multivariate analysis, HS decreased the risk of skin necrosis (p=0.015). Conclusions: HSs do not decrease the seroma rate. However, this method may be useful in skin sparing mastectomy because it decreases skin flap necrosis. © 2013 Surgical Associates Ltd.

Physicochemical and mechanical properties of zirconium oxide and niobium oxide modified Portland cement-based experimental endodontic sealers

Aim: To evaluate the physicochemical and mechanical properties of Portland cement-based experimental sealers (ES) with different radiopacifying agents (zirconium oxide and niobium oxide micro- and nanoparticles) in comparison with the following conventional sealers: AH Plus, MTA Fillapex and Sealapex. Methodology: The materials were tested for setting time, compressive strength, flow, film thickness, radiopacity, solubility, dimensional stability and formaldehyde release. Data were subjected to anova and Tukey tests (P < 0.05). Results: MTA Fillapex had the shortest setting time and lowest compressive strength values (P < 0.05) compared with the other materials. The ES had flow values similar to the conventional materials, but higher film thickness (P < 0.05) and lower radiopacity (P < 0.05). Similarly to AH Plus, the ES were associated with dimensional expansion (P > 0.05) and lower solubility when compared with MTA Fillapex and Sealapex (P < 0.05). None of the endodontic sealers evaluated released formaldehyde after mixing. Conclusion: With the exception of radiopacity, the Portland cement-based experimental endodontic sealers presented physicochemical properties according to the specifications no 57 ANSI/ADA (ADA Professional Product Review, 2008) and ISO 6876 (Dentistry - Root Canal Sealing Materials, 2012, British Standards Institution, London, UK). The sealers had setting times and flow ability that was adequate for clinical use, satisfactory compressive strength and low solubility. Additional studies should be carried out with the purpose of decreasing the film thickness and to determine the ideal ratio of radiopacifying agents in Portland cement-based root canal sealers. © 2013 International Endodontic Journal.