Physical and Mechanical Evaluation of Five Suture Materials on Three Knot Configurations: An in Vitro Study.

The aim of this study was to evaluate and compare the mechanical properties of five suture materials on three knot configurations when subjected to different physical conditions. Five 5-0 (silk, polyamide 6/66, polyglycolic acid, glycolide-e-caprolactone copolymer, polytetrafluoroethylene) suture materials were used. Ten samples per group of each material were used. Three knot configurations were compared A.2=1=1 (forward⁻forward⁻reverse), B.2=1=1 (forward⁻reverse⁻forward), C.1=2=1 (forward⁻forward⁻reverse). Mechanical properties (failure load, elongation, knot slippage/breakage) were measured using a universal testing machine. Samples were immersed in three different pH concentrations (4,7,9) at room temperature for 7 and 14 days. For the thermal cycle process, sutures were immersed in two water tanks at different temperatures (5 and 55 °C). Elongation and failure load were directly dependent on the suture material. Polyglycolic acid followed by glycolide-e-caprolactone copolymer showed the most knot failure load, while polytetrafluoroethylene showed the lowest (P < 0.001). Physical conditions had no effect on knot failure load (P = 0.494). Statistically significant differences were observed between knot configurations (P = 0.008). Additionally, individual assessment of suture material showed statistically significant results for combinations of particular knot configurations. Physical conditions, such as pH concentration and thermal cycle process, have no influence on suture mechanical properties. However, knot failure load depends on the suture material and knot configuration used. Consequently, specific suturing protocols might be recommended to obtain higher results of knot security.

The effect of an 810-nm diode laser on postoperative pain and tissue response after modified Widman flap surgery: a pilot study in humans.

BACKGROUND: The purpose of this single-masked pilot clinical study is to compare the tissue response and postoperative pain after the use of a diode laser (810 nm) (DL) as an adjunct to modified Widman flap (MWF) surgery to that of MWF alone. METHODS: Thirteen patients with generalized severe chronic periodontitis completed the study. Control sites were randomly selected to receive an MWF and the contralateral test sites an MWF in conjunction with a DL. The study tooth/site was treated plus any additional teeth in the quadrant in which the site was located, if needed. Randomization was done using a coin flip. The DL was used to de-epithelialize the inner part of the periodontal flap and photo-biostimulate the surgical area. Pain scale assessment (PS), pain medication consumption (PM), tissue edema (TE), and tissue color (TC) were evaluated 1 week after surgery. RESULTS: Statistically significant differences were seen for TE (P = 0.041), PM (P <0.001), and PS (P <0.001) favoring test sites. TC did not show a statistically significant difference (P = 0.9766). Patients rated the first surgical treatment (test or control; random assignment to first treatment) performed as more painful than the second (P <0.002). CONCLUSION: The use of an 810-nm diode laser provided additional benefits to MWF surgery in terms of less edema and postoperative pain.

In vitro evaluation of the root surface microtopography following the use of two polishing systems by Confocal Microscopy (CFM) and Scanning Electron Microscope (SEM).

OBJECTIVES: To compare and evaluate the root surface roughness after using two polishing instruments for root planing. MATERIALS AND METHODS: This comparative study was carried out on a sample of ten extracted human teeth with twenty interproximal root surfaces. Control group 1 and 2: (n=20 root surface): Gracey Curettes, 15 vertical strokes. Test group 1 (n=10): control group 1 + Termination Diamond Curettes (TDC), 15 strokes. Test group 2 (n=10): control group 2 + Termination Diamond Burs -15 µm (TDB), with irrigation for 15 seconds at 3000 rpm. The root surface was planed with the polishing instruments and test measurements were obtained with Confocal Microscopy (CFM) and Scanning Electron Microscope (SEM). The primary outcome variable was surface roughness (Ra). RESULTS: CFM showed that the TDC, mean changes in surface roughness (Ra) were reduced by 0.11 ± 0.14 (p-value = 0.000), and the TDB, Ra: were reduced by 0.27 ± 0.86 (p-value = 0.037). Non-statistically significant differences were observed in Ra (p-value = 0.581) between the two polishing instruments. SEM showed that the Group 2 showed a generally rougher surface with more parallel grooves than Group 1. CONCLUSION: There are no statistically significant differences between these two polishing systems, although TDB seems to reduce the surface roughness more than the TDC after being treated with Gracey Curettes.