Comparison of the recurrence rate of different surgical techniques for oral mucocele: A systematic review and Meta-Analysis

Background: There are different surgical techniques to remove Oral mucoceles, including conventional surgery with scalpel, removal of the lesion with CO2 laser, and micro marsupialization. The present systematic review was conducted with the aim of comparing the recurrence rate of different surgical techniques for treatment of the oral mucoceles. Material and Methods: An electronic search for randomized controlled trials published in English until September 2022 related to different surgical methods for the treatment of oral mucocele was performed in Medline/PubMed, Web of Science, Scopus, Embase and Cochrane databases. A random-effects meta-analysis was conducted to compare the recurrence rate of different techniques. Results: Among 1204 papers initially identified, after the removal of duplicate articles and screening of the titles and abstracts, fourteen full-text articles were reviewed. Seven articles comparing the recurrence rate of oral mucocele in different surgical techniques were found. Seven studies were included in qualitative studies, and five articles were included in the meta-analysis. The risk of mucocele recurrence in the micro-marsupialization technique was 1.30 times that of the surgical excision with scalpel technique, which was not statistically significant. The risk of mucocele recurrence in the CO2 Laser Vaporization technique was 0.60 times that of the Surgical Excision with Scalpel technique, which was not statistically significant. Conclusions: The results of this systematic review showed that there is no significant difference between the recurrence rate of surgical excision, CO2 laser and marsupialization techniques for the treatment of oral mucoceles. Although more randomized clinical trials are needed for definitive results. (AU)

Optimal adaptive interval type-2 fuzzy fractional-order backstepping sliding mode control method for some classes of nonlinear systems.

In this research, a novel adaptive interval type-2 fuzzy fractional-order backstepping sliding mode control (AIT2FFOBSMC) method is presented for some classes of nonlinear fully-actuated and under-actuated mechanical systems with uncertainty. The AIT2FFOBSMC method exploits the advantages of backstepping and sliding mode methods to improve the performance of closed-loop control systems by lowering the tracking error and increasing robustness. To mitigate chattering and the tracking error, a fractional sliding surface is designed. In addition to the fractional sliding surface, an adaptive interval type-2 fuzzy compensator is used to estimate the uncertainty and perturbation of the nonlinear system in order to further reduce chattering caused by switching term as well as to enhance the perturbation rejection. In order to achieve an optimal performance, the multi-tracker optimization algorithm (MTOA) is used. Finally, a number of simulations and experimental tests are carried out to examine the performance of the AIT2FFOBSMC method.

Optimal interval type-2 fuzzy fractional order super twisting algorithm: A second order sliding mode controller for fully-actuated and under-actuated nonlinear systems.

In this paper, a novel interval type-2 fuzzy fractional order super twisting algorithm (IT2FFOSTA) which is essentially a second order sliding mode controller is presented. The proposed IT2FFOSTA enhances fractional order super twisting algorithm (FOSTA) by taking advantage of an interval type-2 fuzzy fractional order sliding surface (IT2FFOSS) for some classes of fully-actuated and under-actuated nonlinear systems in presence of uncertainty. The FOSTA significantly reduces the amount of chattering and the IT2FFOSS results in decreasing the tracking error, control effort, and chattering level. In order to control under-actuated systems, a hierarchical sliding surface is employed. The multi-tracker optimization algorithm is utilized to adjust the controller's parameters; this leads to an optimal performance for the IT2FFOSTA. To examine the performance of the IT2FFOSTA, some simulation and experimental tests on three examples of different classes of fully-actuated and under-actuated systems, including ball and plate, inverted pendulum, and ball and beam systems are carried out. The simulation and experimental results demonstrate the superiority of the IT2FFOSTA in reducing the amount of chattering, tracking error, and control effort compared to those of the other control methods.

Simulation and experimental control of a 3-RPR parallel robot using optimal fuzzy controller and fast on/off solenoid valves based on the PWM wave.

In this paper, a robust optimal fuzzy controller based on the Pulse Width Modulation (PWM) technique is proposed to control a laboratory parallel robot using inexpensive on/off solenoid valves. The controller coefficients are determined using Modified Cuckoo Optimization Algorithm. The objective function of this method is considered such that the results show the position tracking by the robot with less force and more efficiency. Regarding the results of experimental tests, the control strategy with on/off valves indicates good performance such that the maximum value of RMS of error for a circular path with increasing force on the system is 3.1mm. Furthermore, the results show the superiority of the optimal fuzzy controller compared with optimal PID controller in tracking paths with different conditions and uncertainties.