Objective: Ergonomics in dental practice plays a crucial role in maintaining professional health, as prolonged static postures and repetitive movements significantly increase the risk of work-related musculoskeletal disorders among dental professionals. Understanding ergonomic risk factors and their impact on musculoskeletal health is essential for identifying vulnerable groups and developing effective preventive strategies in dental practice. Aim: The aim of this study was to assess the occurrence of musculoskeletal pain as a manifestation of work-related musculoskeletal disorders among dentists and to analyze its association with demographic characteristics, work habits, and dental specialization. Materials and Methods: This cross-sectional study included 130 dentists from various dental specialties. Data were collected using a structured questionnaire addressing demographic variables, work habits, ergonomic conditions, and the presence of musculoskeletal pain. Descriptive statistical methods were applied, and chi-square tests were used to analyze associations between categorical variables, with statistical significance set at p < 0.05. Results: The results indicated that the majority of participants experienced work-related musculoskeletal disorders, with prevalence increasing with age and length of professional experience. Occupational factors such as prolonged sitting or standing, improper working posture, lack of ergonomic chairs, and insufficient physical activity were significantly associated with the occurrence of work-related musculoskeletal disorders (p < 0.05). A statistically significant association was also observed between dental specialty and the presence of work-related musculoskeletal disorders (χ²(9) = 25.83; p < 0.01). The highest prevalence was reported among specialists in prosthodontics, pediatric dentistry, orthodontics, and endodontics, while lower prevalence was observed among oral surgeons, general dental practitioners, and periodontists. Conclusion: These findings emphasize the importance of implementing ergonomic interventions, regular physical activity, and preventive strategies in dental practice to reduce the occupational risk of work-related musculoskeletal disorders.

Introduction: The main purpose of root canal filling materials is to provide an apical sealing that prevents the movement of bacteria and the diffusion of their metabolic products from the root canal system to periapical tissue. The aim of this study was to evaluate the apical sealing ability of mineral trioxide aggregate’s (MTA), epoxy resin, and zinc oxide eugenol- based sealer with single cone obturation techniques using the dye extraction leakage method. Methods: Seventy-five extracted human single-rooted teeth were instrumented using the crown-down technique with the Mtwo rotary file system to file 25/6. The teeth were randomly divided into five experimental groups (n = 15); Group 1 obturated with AH plus, Group 2 obturated with MTA BIOSEAL, Group 3 obturated with Endoseal, Group 4 positive control (POS CTRL) root canals are processed but not obturated, and negative control- apex of teeth completely covered with nail varnish, canals are not treated or obturated. In the first three groups, the single cone obturation technique with gutta-percha 25/6 was used. Apical microleakage was assessed with the dye extraction method, where the absorbance of 2% methylene blue was measured using a spectrophotometer. Results: The mean dye concentration values were MTA 22.79, AH plus 31.16, Endoseal 36.67, POS CTRL 280.15, negative control 9.01. Analysis of variance and pairwise comparisons indicated a significant difference in apical microleakage between the investigated groups (F = 3448, p < 0.001). The MTA BIOSEAL showed significantly less apical microleakage than the AH plus and Endoseal. The AH plus showed less apical microleakage than the Endoseal, although there was no significant difference between these two sealers. Conclusion: With the limitation of the study, it was concluded that MTA sealers show statistically less apical leakage than AH Plus and Endoseal.

Herbal medicine has long been essential in preventing and treating oral health issues, dating back to prehistoric times. Over the centuries, different cultures have developed advanced herbal remedies for conditions such as toothaches, gingivitis, oral ulcers, and bad breath. Recent research highlights the therapeutic benefits of plants like sage, aloe vera, miswak, clove, neem, chamomile, and mint, many of which are now incorporated into modern oral care products. The combination of ancient wisdom with contemporary scientific research reinforces the ongoing role of phytotherapy in modern dental practice.

(1) Background: This study evaluates the effect of a conventional/low-voltage light-curing protocol (LV protocol) (10 s with 1340 mW/cm2) and high-voltage light-curing protocol (HV protocol) (3 s with 3440 mW/cm2) on the microhardness (MH) of dental resin-based composites (RBCs). Five resin composites were tested: conventional Evetric (EVT), Tetric Prime (TP), Tetric Evo Flow (TEF), bulk-fill Tetric Power Fill (PFL), and Tetric Power Flow (PFW). (2) Materials and Methods: Two tested composites (PFW and PFL) were designed for high-intensity light curing. The samples were made in the laboratory in specially designed cylindrical molds; diameter = 6 mm and height = 2 or 4 mm, depending on the type of composite. Initial MH was measured on the top and bottom surfaces of composite specimens 24 h after light curing using a digital microhardness tester (QNESS 60 M EVO, ATM Qness GmbH, Mammelzen, Germany). The correlation between the filler content (wt%, vol%) and the MH of the RBCs was tested. For the calculation of depth-dependent curing effectiveness, the bottom/top ratio for initial MH was used. (3) Conclusions: MH of RBCs is more dependent on material composition than on light-curing protocol. Filler wt% has a greater influence on MH values compared to filler vol%. The bottom/top ratio showed values over 80% for bulk composites, while for conventional sculptable composites, borderline or suboptimal values were measured for both curing protocols.

Abstract Objectives  The aim of the study was to analyze the occurrence of stress on teeth with abfraction lesions restored with six different restorative materials, and by introducing the tensile strength parameters to calculate the safety factor of the material under the load (ratio between the strength of the material and the maximum stress). Materials and Methods  Three-dimensional models of the mandibular premolar are created from a microcomputed tomography images. An abfraction lesion is modeled on the tooth. The stress of the dental tissues and six restorative materials under functional and nonfunctional occlusal loading of 200 (N) are analyzed by finite element method. Statistical Analysis  CTAn program 1.10 and ANSYS Workbench (version 14.0) were used for analysis. Results are presented in von Mises stress. Results  Oblique loads caused ≈ four times higher stress in restorative materials than the axial ones. It is noticeable that high values of von Mises stress are measured at the bottom of the sharp lesion, even up to 240 MPa, that are significantly reduced after the restoration. The highest stresses at the restorative material are present at the lower (gingival) margin of the restoration. The highest stresses under both types of loads are measured in nanohybrid composite (Tetric EvoCeram, Ivoclar Vivadent). The lowest values of the stress are measured in the flowable composite (Tetric Flow, Ivoclar Vivadent), but at the same time, the highest value of the stress is measured in the surrounding dental tissues on the tooth restored with the flowable composite. The microhybrid composite (Herculite XR, Kerr), with the highest safety factor, is the material that best withstands the stresses it is exposed to. The obtained safety factor did not exceed the critical limit, except for the glass ionomer cement, with the safety factor lower than 1. Conclusion  The type of tooth loading has the greatest influence on the intensity of stress. The value of the obtained stresses in the restorative material and dental tissues differ due to the different mechanical properties of the materials. Restoration of noncarious lesions significantly reduces extremely high stress values at their bottom.

OBJECTIVE The aim of this paper was to analyze the distribution of stress and deformation on the mandibular first premolar under two types of loading (axial and para-axial load of 200 N) using the FEM computer method. MATERIALS AND METHOD For this research a µCT scan of the first mandibular premolar was used, and the method used in this research was FEM analysis under two types of loading. RESULTS The values of the von Mises stress measured in the cervical part of an intact tooth under axial load were up to 12 MPa, and under paraaxial load over 50 MPa. The values of the stress measured on the bottom of the noncarious lesion are very high ≈ 240 Mpa. Stress values in the cervical part of the intact tooth are higher in the zone of the sub-surface enamel. The deformation values of the tooth under para-axial loading were ≈ 10 times higher than the value of the deformation under axial load. The greatest deformations were seen in the area of the tooth crown. CONCLUSIONS Occlusal loading leads to significant stress in the cervical part of teeth. The values of the measured stress are greater under the action of paraxial load. The values of stress in abfraction lesions measured under a paraxial load are extremely high. Exposing the lesion to further stress will lead to its deepening. The total deformation of the entire tooth under paraxial load was ≈ 10 times higher compared to the deformation value of the tooth under axial load.

Adresa za dopisivanje Alma Dozic ACTA, Academic Center for Dentistry in Amsterdam Department of Dental Materials Gustav Mahlerlaan 3004 1081 LA Amsterdam, Netherland a.dozic@acta.nl Sažetak Ljudski zubi građeni su od organskih i anorganskih tkivnih komponenata sličnih kostima. Može se pretpostaviti da strukturalna promjena boje zuba u različitim prirodnim uvjetima može poslužiti u forenzičnoj tafonomiji kao, na primjer, u slučaju kad se potvrđuje okoliš i uvjeti ukopa te vrijeme provedeno nakon smrti (PMI-a). Danas se uočavaju i vrlo male promjene u nijansi zuba zahvaljajući dobro razvijenim dentalnim spekrtofotometrima. Poznato je da zubi, ako su izloženi utjecaju zraka, brzo dehidriraju, ali stupanj i način tih promjena u vremenskom intervalu dosad nije objektivno izmjeren. Svrha istraživanja: Svrha ovog istraživanja bila je odrediti stupanj i obrazac promjene boja zuba izloženih određeno vrijeme trima različitim uvjetima. Materijal i postupci: Za istraživanje su odabrani impaktirani treći kutnjaci zato što do tada nisu bili izloženi okolišnim uvjetima. Njihove vrijednosti CIE L*a*b* nakon ekspozicije u suhim uvjetima, natrijevu kloridu (NaCl) i umjetnoj slini (kontrola) izmjerio je iskusni stručnjak dentalnim spektrofotometrom u razmacima od 1 sat, 24 sata, 1 tjedan, 3 tjedna, 5 tjedana i 7 tjedana. Rezultati: Vrijednosti koordinata za L*-lightness (svjetlost) i b*-blue-yellow (plavo-žutu boju) bile su znatno povišene u suhim uvjetima (p < ,001 za svjetlost i p ≤ ,050 za boju), a koordinate za a*-green-red (zeleno-crveno) nisu pokazale statistički značajan pomak. Izloženost ekstrahiranih trećih kutnjaka suhim uvjetima prouzročila je veliko povećanje kordinata L* i b* prema svjetlijem i žućem dijelu, u usporedbi s izloženošću zuba umjetnoj slini i natrijevu kloridu, u svim testiranim uvjetima koordinata a* pokazala se kao vrlo promjenljiva. Zaključak: Izloženost ekstrahiranih impaktiranih umnjaka suhim uvjetima uzrokovala je znatno uzastopno povećanje vrijednosti L* i b* u usporedbi s izloženošću zuba natrijevu kloridu i umjetnoj slini. Ključne riječi forenzička stomatologija; smrt; vlaga; zub; odontometrija; kolorimetrija 1 ACTA – Stomatološki akademski centar u Amsterdamu, Zavod za dentalne materijale, Amsterdam, Nizozemska ACTA, Academic Center for Dentistry in Amsterdam, Department of Dental Materials, Amsterdam, Netherland 2 Stomatološki fakultet Sveučilišta u Sarajevu, BiH Faculty of Dentistry, University of Sarajevo, Bosnia and Herzegovina 3 Zavod za sudsku medicinu i kriminalistiku Medicinskog fakulteta Sveučilišta u Rijeci, Hrvatska Department of Forensic Medicine and Criminalistics, Rijeka University School of Medicine, Croatia