Comparative Evaluation of the Repair Bond Strength of Dental Resin Composite after Sodium Bicarbonate or Aluminum Oxide Air-Abrasion.

The dental prophylactic cleaning of a damaged resin-based composite (RBC) restoration with sodium bicarbonate can change the surface characteristics and influence the repair bond strength. The purpose of this study was to compare the effect of sodium bicarbonate (SB) and aluminum oxide (AO) surface treatments on the microtensile bond strength (µTBS) of repaired, aged RBC. Bar specimens were prepared from microhybrid RBC and aged in deionized water for 8 weeks. Different surface treatments (AO air-abrasion; SB air-polishing), as well as cleaning (phosphoric acid, PA; ethylene-diamine-tetraacetic-acid, EDTA) and adhesive applications (single bottle etch-and-rinse, ER; universal adhesive, UA), were used prior to the application of the repair RBC. Not aged and aged but not surface treated RBCs were used as positive and negative controls, respectively. The repaired blocks were cut into sticks using a precision grinding machine. The specimens were tested for tensile fracture and the µTBS values were calculated. Surface characteristics were assessed using scanning electron microscopy. AO-PA-UA (62.6 MPa) showed a 20% increase in µTBS compared to the NC (50.2 MPa), which proved to be the most significant. This was followed by SB-EDTA-UA (58.9 MPa) with an increase of 15%. In addition to AO-PA-UA, SB-EDTA-UA could also be a viable alternative in the RBC repair protocol.

Endoscopic removal of a dental implant displaced into the maxillary sinus: A case presentation and a review of the literature / Arcüregbe diszlokált fogimplantátum eltávolítása endoszkópos ellenorzéssel: Esetismertetés a szakirodalom tükrében

Összefoglaló. Az utóbbi idoben egyre gyakoribbá vált fogászati implantáció egyik nem kívánt szövodménye az arcüregbe került implantátum, amely a maxilla molaris, esetenként praemolaris régiójának implantációjakor fordulhat elo. Ennek oka lehet a kúpsugaras komputertomográfia nélküli, azaz nem megfelelo tervezés, fennálló arcüreggyulladás és -ventilációs probléma, kevés, puha csont, a fúrási vagy implantátumbehelyezési sebészi gyakorlat hiánya, észre nem vett membránperforáció arcüreg-csontfeltöltés esetén. Esetünkben implantáció elott a beteg szájsebész orvosa kúpsugaras komputertomográfia alapján sinusventilációs zavart és arcüreggyulladást véleményezett. Az arcüreggyulladás funkcionális endoszkópos sinussebészeti mutéttel történo kezelését és gyógyulását követoen két lépésben, eloször arcüreg-csontfeltöltést, majd 6 hónappal késobb implantációt végeztek. 4 hónap panasz- és tünetmentes gyógyulást követoen az implantátumfeltárás elott derült fény az arcüregbe került implantátumra, amelyet funkcionális endoszkópos sinussebészeti eljárással, transnasalis (Lothrop) és intraoralis behatolás kombinációjával távolítottunk el. Az implantátumok arcüregbe kerülésének gyakorisága továbbra is ismeretlen, a szakirodalomban kb. 70 közölt esetrol tudunk; a leggyakrabban egy-egy implantátummal kapcsolatban születnek cikkek, ami az összes beültetett implantátum számához képest elenyészo. Az arcüregben lévo szabad implantátum arcüreggyulladást okoz, eltávolítása szükséges, kötelezo. A sinus hátsó részében elhelyezkedo implantátum esetén elsosorban funkcionális endoszkópos sinussebészeti eljárás javasolt. Az elso recessusban lévo implantátum eltávolítására a legjobbnak a praelacrimalis recessusból végzett korszeru behatolás tunik. Tradicionális transoralis/Luc-Caldwell-féle behatolást a friss sinuslift utáni gyulladt csontexcochleatio esetén javasolunk, illetve ha fennálló oroantralis fistulát is zárnunk kell. Orv Hetil. 2022; 163(13): 527-531. Summary. Accidental implant displacement into the maxillary sinus is often due to inappropriate surgical planning or technique, unrecognised sinus disease, failure to recognise low residual bone quality and quantity during implant-supported maxillary molars and premolars rehabilitation. Secondary implant migration can be attributed to the risk of failing osteointegration due to unnoticed sinus membrane rupture during surgery, incomplete soft tissue closure over the implant's site, preexistent sinus ventilation problems. In this study, we present the case of a patient with a symptomless preexistent sinus infection, which had been treated with functional endoscopic sinus surgery. After the healing period, the following two-stage procedures were performed: 1) maxillary sinus bone augmentation, 2) 6 months later dental implant placement, based on a routine orthopantomogram. At the end of the 4-month planned healing period, the implant displacement was noticed in the sinus cavity. The implant was removed with a combination of endoscopic surgery, transnasal and transoral Luc-Caldwell approach. The possible reasons for displaced implant into the sinus cavity, the treatment decision tree and lessons we learned, updated by the international literature, are discussed. Our recommendation for displaced implant removal is primarily transnasal under general anaesthesia. In the case of the implant in the anterior recess of the maxillary sinus, the functional endoscopic sinus surgery through the prelacrimal recess approach seems to be the preferred approach. A transoral approach should be the chosen method in the case of present oro-anthral fistulae or recent sinus bone graft, when the infected graft should also be removed. Orv Hetil. 2022; 163(13): 527-533.

Effectivity of near-peer teaching in training of basic surgical skills - a randomized controlled trial.

BACKGROUND: Near-peer teaching (NPT) is a special way of teaching where the tutor is one or more academic years ahead of the person being tutored. The literature agrees on the benefits of the method, but there are only a few publications examining its effectiveness using objective methods. The aim of our study was to examine the effectiveness of NPT in the training of basic surgical skills. METHODS: We included 60 volunteer students who participated in a 20 × 45 min long surgical skills course. Based on the results of a pre-course test, we randomly divided the students into six equal groups. All groups completed the same curriculum, with three groups being assisted by a NPT tutor. After the course, they completed the same test as at the beginning. The exams were recorded on anonymized videos and were blindly evaluated. The students' satisfaction was monitored using a self-administered online anonymous questionnaire. Statistical analysis was performed using the Mann-Whitney and Wilcoxon tests. RESULTS: Overall, student performance improved with completion of the course (from 119.86 to 153.55 points, p <  0.01). In groups where a NPT tutor assisted, students achieved a significantly better score (37.20 vs. 30.18 points improvement, p = 0.036). The difference was prominent in surgical knotting tasks (14.73 vs. 9.30 points improvement, p <  0.01). In cases of suturing (15.90 vs. 15.46 points) and laparoscopy (7.00 vs. 4.98 points), the presence of the NPT tutor did not significantly affect development. Based on student feedback, although students positively assessed the presence of NPT, it did not significantly improve students' overall satisfaction since it was already 4,82 on a scale of 5 in the control group. CONCLUSIONS: Overall, involving a NPT tutor had a positive impact on student development. An outstanding difference was observed in connection with knotting techniques.