Evaluation of Effectiveness of Cement Removal From Implant-Retained Crowns Using a Proposed "Circular Crisscross" Flossing Technique

Extruded cement during dental implant crown cementation may cause peri-implant diseases if not removed adequately. The purpose of this study was to evaluate the efficiency of removal of cement after cementation of implant crowns using an experimental circular crisscross flossing technique (CCFT) flossing technique, compared to the conventional "C"-shape flossing technique (CSFT). Twenty-four patients rendered 29 experimental and 29 control crowns. Prefabricated abutments were secured to the implant such that the margins were at least 1 mm subgingivally. The abutments were scanned using computer-aided design/computer-aided manufacturing technology and Emax crowns were fabricated in duplicates. Each crown was cemented individually and excess cement was removed using the CSFT and the CCFT techniques. After completion of cementation was completed, the screw access holes were accessed and the crown was unscrewed along with the abutment. The samples were disinfected using 70% ethanol for 10 minutes. Crowns were divided into 4 parts using a marker to facilitate measurement data collection. Vertical and horizontal measurements were made for extruded cement for each control and experimental groups by means of a digital microscope. One-hundred and seventeen measurements were made for each group. Mann-Whitney test was applied to verify statistical significance between the groups. The CCFT showed a highly statistically significant result (104.8 ± 13.66, P < .0001) for cement removal compared with the CSFT (291.8 ± 21.96, P < .0001). The vertical measurements of the extruded cement showed a median of 231.1 μm (IQR = 112.79-398.39) and 43.62 μm (IQR = 0-180.21) for the control and the experimental flossing techniques, respectively. The horizontal measurements of the extruded cement showed a median of 987.1 μm (IQR = 476.7-1,933.58) and 139.2 μm (IQR = 0-858.28) for the control and the experimental flossing techniques, respectively. The CCFT showed highly statistically significant less cement after implant crowns cementation when compared with the CSFT.