Sample and study design
swelling, Lindemann stainless steel
TEMPOROMANDIBULAR JOINT DISORDER, IMPACTED TEETH, BLIND
A randomized, split-mouth, single-blind study was conducted on patients referred at the Oral Surgery Unit of the School of Dentistry of the University of Messina, ranging between 18 and 40 years of age and requiring lower third molars extraction. Study protocol was based on an already validated operative scheme [Sample size was calculated using the data derived from a preliminary analysis on 10 subjects previously conducted by the authors in order to estimate the considered main outcome (swelling) variation. Values obtained from the preliminary analysis and used to perform the sample size calculation of R group and P group were 1.62 and 1.38 respectively, with a shared standard deviation (σ) of 0.28; power analysis was performed setting α = 0.5 and 0.8 power level. A sample size of 22 subjects was therefore obtained.Twenty-two patients were recruited during an 8 months period according to the following criteria: good general health conditions; no clinical evidence of major facial asymmetry; presence of bilateral and symmetrical impacted third molars (according to the classifications of Winter and Pell and Gregory); no use of medication that would influence or alter wound healing; no temporomandibular joint disorder history; no smoking.The patients were included in the study after the registration of personal and clinical data and the collection of TC scan of the teeth to be extracted.The local Ethical Committee of Messina approved the study protocol (ID 01–2020, on 04/27/2020), in accordance with the Helsinki declarations. The study was registered on ClinicalTrials.gov (ID: NCT05488028).Patients had given their consent to treatment and were informed that their data would be used for statistical analyses related to this study; informed consent was obtained from all participants.Randomization was conducted with a table of casual numbers by an investigator who was not part of the study and who was blind to the identity of the procedures.All patients were enrolled in two groups, P group included all the surgeries carried out with piezoelectric technique, while operations carried out with the bur were assigned to R group.All patients underwent a 3-d facial scan before the surgical teeth removal using Bellus 3D Dental Pro (Bellus 3D, Inc. 1901 S. Bascom Ave. Suite 1300 Campbell, CA 95,008 USA).Bellus 3D Dental Pro is a dental app for iOS devices that uses the integrated to scan and reproduce the face of a subject with a 3-dimensional render in less than 15 s. The facial scan can be subsequently exported in various formats, such as STL.For each patient, the impacted teeth were extracted in two different phases, separated by a 30-day time interval. All procedures were performed by a single experienced oral surgeon.The study involved three time points:• reference scan (T0), face scan before surgery, at time 0;• target scans (T1) and (T2), respectively at 3 and 7 days, after each surgery, both with rotating and piezoelectric instrumentation for a total of 5 scans.The Esacrom Piezosurgery device (Esacrom electronics and medical devices, Imola, Italy) was used for ultrasonic osteotomies according to the manufacturer's instructions using a specific insert for osteotomies (ES07WT).The Lindemann stainless steel bur (shank diameter 2.35 mm; length 44 mm) mounted on a high-speed straight surgical handpiece was used for osteotomies with conventional technique.