THE USE OF THE OPERATING MICROSCOPE IN DENTAL PRACTISE: POSTURAL ANALYSIS AND CLINICAL EVALUATION

THE USE OF OPERATING MICROSCOPE IN DENTAL PRACTISE: POSTURAL ANALYSIS AND CLINICAL EVALUATION Abstract Author: Alberto Pispero Dipartimento di Scienze Biomediche, Chirurgiche ed Odontoiatriche, Università degli Studi di Milano The study is in collaboration with Politecnico di Milano, Dipartimento di Ingegneria Elettronica, prof. Marco Marcon Study design: randomized controlled clinical trial. Setting of the clinical trial: Dental Clinic G. Vogel, via Beldiletto ASST Santi Carlo e Paolo Ospedale. Dr. Alberto Pispero, the surgeon for all the interventions; Prof. Giovanni Lodi is the head of research. PURPOSE The study investigates the effectiveness of microscope in dental practice in terms of posture improvement for the operator and clinical advantages for the patients. We carried out 4 studies: 1. Postural assessment in dentistry based on multiple markers tracking 2. The use of magnifying instrument for the extraction of lower third molar: Postural assessment 3. The use of magnifying instrument for the extraction of lower third molar: Clinical assessment 4. The influence of dental loupes on the quality of adhesive removal in orthodontic debonding: in vitro study. Background Attention and awareness towards MSDs in the dental profession has increased considerably in last years. From recent literature reviews, it is learned that prevalence of MSDs in dentists is 64-93%. Use of magnification systems improves the operator's visual capabilities, improves posture, and helps to prevent the onset of back and neck disorders. Moreover, the goal of dental treatment is to preserve tissues with minimally invasive prosthetics, conservatives and endodontics therapies, and to reconstruct periodontal soft and hard tissues performing microsurgery treatments in order to get the best aesthetic results and the least pain and complications. Over time, the degree of precision required immediately calls for magnification. METHODS Study 1: First, we conducted a study (study 1) on posture assessment to find an innovative method of postural analysis. In order to do that we worked with Politecnico of Milano. We presented a novel approach for upper limb posture assessment based on the tracking of a set of planar markers placed on the clothes of the worker. Thanks to this non-invasive approach, we were able to follow the 3D position and orientation of all the limbs involved in a specific activity during the job execution. Data will be evaluated through the index RULA (rapid upper limb assesment) to define whether there is a change in exposure to the risk of MSDs (Muskolo - skeletal - disease). Study 2: We used the method mentioned above in a randomized controlled three arms clinical trial where the surgeons performed 90 intervention. It was evaluated dentist posture during extraction of third lower molars depending on whether the operator performs the intervention by the use of surgical loupes or surgical microscope systems or performs a naked eyes surgery. Static and dynamic operator’s posture has been monitored by markers positioned on a slim fit t-shirt and high definition cameras acquired data in real time (study 2). Study 3: To evaluate whether the use magnifying system, could influence the postoperative course of a patient after extraction of a lower third molar. Each patient will be recalled for follow-up visits at 7 days. During this session will be carried out the removal of stitches and data will be recorded as follows: VAS pain and trismus, number of painkillers taken, control photographs, Posse Scale. These data were analyzed considering type of magnification and difficulty of extraction (study 3). Study 4: In order to investigate the effect of using different magnifying systems for removal of composite residues and in the prevention of iatrogenic enamel damage we conducted an in vitro study. 27 permanent extracted teeth were used, The teeth were randomized into 3 groups named. Each tooth was photographed and scanned with the intraoral scanner CS3600-Carestream before bracket placement (T0), post bracket positioning (T1), after removal of bracket (T2) and after debonding (T3). RESULTS Study 1: The analysis that we performed can be easily integrated into classical ergonomics assessment tools like RULA providing an objective methodology that does not involve an operator in a subjective interpretation of the monitored job. Study 2: From step 1 to step 8 in RULA worksheet, we put the same score in all cases, in the same way in steps 11, 13 and 14. By the use of magnification system, the operator’s posture didn’t change in terms of leg positioning or arm raising and wrist twist. We verified that despite the big range between neck bending, from 40 to 3 degrees, the final RULA score is the same for all interventions. Study 3: From the results obtained it is clear that the methods taken into consideration, the operating microscope, the surgical loupes with coaxial illumination and the naked eye, do not have a statistically significant influence on pain intensity (VAS), quality of life (PoSSe) or the number of painkillers taken by patients. The complexity of the magnifying system does not increase the duration of the operating time Study 4: There is a statistically significant difference between the procedures performed with the naked eye and those performed with surgical loupes. This result can be explained by greater attention and accuracy in removing the residual composite from the operator when using magnification systems. Microscope and surgical loupes were slower but got the best results in removal of composite remnants. Intraoral scanner that we used to evaluate the teeth surfaces does not appear useful to discriminate damage to the enamel. CONCLUSION We developed a new approach for posture assessment, precise and accurate, and we have had 3d data of the whole body, which can discriminate differences of one degree. We need long term studies conducted on many dentists (male and female) and a new method of posture data analysis to define the correlation between upper limbs posture and WMSDs accurately. We wanted to test magnification systems in fields of dentistry different from endodontics in which microscope is generally used. Even if data had no statistical significance, on the other hand microscope didn't affect the operating time. Despite common perceptions, the use of the microscope in oral surgery didn't slow down the intervention. We decided to test the microscope potential in debonding. In our research, the procedures performed without a magnification system are on average faster than those performed with the aid of a magnification. This result can be explained by greater attention and accuracy in removing the residual composite from the operator when using magnification systems. Microscope and surgical loupes were slower but got the best results in removal of composite remnants.