In this study, the authors analyzed modern resin materials typically used for temporary reconstructions on implants and manufactured via 3D printing. Three broadly used resins: NextDent Denture 3D, NextDent C&B MFH Bleach, and Graphy TC-80DP were selected for analysis and compared to currently used acrylic materials and ABS-like resin. In order to achieve this, mechanical tests were conducted, starting with the static tensile test PN-EN. After the mechanical tests, analysis of the chemical composition was performed and images of the SEM microstructure were taken. Moreover, numerical simulations were conducted to create numerical models of materials and compare the accuracy with the tensile test. The parameters obtained in the computational environment enabled more than 98% correspondence between numerical and experimental charts, which constitutes an important step towards the further development of numeric methods in dentistry and prosthodontics.

Background/Objectives: The accurate and prosthetically driven placement of dental implants is crucial for long-term clinical success. While computer-aided static navigation enhances precision, the comparative accuracy of different surgical guide support types (teeth-, mucosa-, and bone-supported) under identical clinical conditions remains a critical and less explored variable. This study aimed to compare the accuracy of these three guide types. Methods: This clinical study evaluated the precision of computer-aided implant placement by comparing planned versus actual implant positions in fifty participants who received 140 implants. Discrepancies were measured in 3D using STL files in Exocad^® DentalCAD software (exocad Elefsina 3.2, Darmstadt, Germany). Results: In the maxilla, mean total deviation was 0.443 mm at the implant neck and 0.562 mm at the apex. In the mandible, deviations were higher: 0.755 mm at the neck and 0.981 mm at the apex. Teeth-supported guides demonstrated the highest accuracy. Mucosa-supported guides showed the least precision, particularly in the mandible, while bone-supported guides provided clinically acceptable results. Conclusions: Computer-aided static navigation is highly accurate for implant placement. Guide selection should be tailored to anatomical conditions, with bone-supported guides preferred for edentulous mandibles.

The rapid development of 3D printing technology has enabled its application in many fields, including dentistry. One of the key applications is temporary prosthetic restorations on dental implants, used during the osteointegration process. These restorations provide functionality and aesthetics, but their durability under oral conditions exposed to dynamic loads remains a challenge. This pilot study evaluated the thermal expansion and fatigue resistance of three commercially available photopolymer materials used in 3D printing: NextDent Denture 3D, NextDent C&B MFH Bleach, and Graphy TC-80DP. Thermal expansion and dimensional stability analyses were performed on samples subjected to cyclic heating and cooling. Fatigue tests were designed to evaluate the behaviour of the materials under repetitive mechanical loads mimicking chewing. Microscopic analyses (SEM) made it possible to identify the internal structure of the materials and their damage mechanisms. The results showed that the tested materials have a low coefficient of thermal expansion and high dimensional stability after cyclic heating and cooling. However, significant differences were observed in their mechanical properties and fatigue resistance. The best results were obtained for the Graphy TC-80DP material, while NextDent Denture 3D showed the least resistance to cyclic loading. NextDent Denture 3D exhibited the highest thermal expansion coefficient (123.6 × 10⁻⁶/K), while Graphy TC-80DP showed the lowest (83.9 × 10⁻⁶/K), ensuring better dimensional stability. Fatigue tests revealed that Graphy TC-80DP withstood up to 675,221 cycles at 51 MPa, while NextDent Denture 3D failed after 420 cycles. SEM analysis confirmed that Graphy TC-80DP maintained structural integrity longer, while NextDent Denture 3D exhibited early crack propagation. This study fills a gap in the knowledge of the behaviour of dental materials produced with 3D printing technology under real-world conditions and provides a basis for further, more advanced research to improve their properties and patient comfort.

Background: Complex implant reconstructions in patients with residual dentition due to periodontitis is a challenging task in many aspects. Methods: This study shows a full digital workflow combining 3D printing, guided implant placement, intraoral scanning and welding with immediate loading and digital smile design. An analog impression was taken to validate the passive fit of final restorations. The whole treatment plan was divided into three stages. The first stage included an intraoral scan of baseline dentition, and then the extraction of all teeth was performed, implanting four temporary implants and providing the patient with removable temporary prosthesis. The second stage was to scan the removable temporaries, implanting 10 implants and multi-unit abutments (MUA), and create a rigid construction via the intraoral welding of titanium bar and by fixing it to the 3D-printed temporary reconstructions (designed with DSD) as a form of immediate loading. The third stage included the scanning of screw-retained temporary reconstructions, then scanning from the MUA level and creating final reconstruction. Results: The presented workflow enabled the delivery of some sort of restoration to the patient at every moment of the treatment and to sustain the required esthetic effect with decent comfort of use even in the early stages. Conclusions: A full digital workflow is a reliable treatment method even in complex cases.

Background: The following case report presents the treatment of a patient with severe maxillary atrophy and failing residual dentition. The patient has been diagnosed with stage IV grade C periodontitis, making this case challenging from the very beginning. Methods: The treatment plan was based on collecting and merging digital data: CBCT, a face scan, and an intraoral scan. Due to the advancement of the periodontal disease, the treatment was divided into three stages. The entire process was conducted in a digital manner, based on the concept of prosthetically driven implantology. Additionally, all prosthetic temporaries were planned via digital smile design. Stage I included extracting the residual dentition, placing four implants in the mandible, and the delivery of a 3D-printed upper removable denture. Stage II included placing two zygomatic implants, two anchored piriform rims, and one midline implant. Both arches were immediately loaded with the intraoral welding of abutments screwed to multiunit abutments and 3D-printed shells. Subsequently, in stage III, two milled ceramic superstructures combined with a titanium milled bar were delivered as a final screw-retained restoration with the application of scan flags (horizontal scan bodies) for intraoral scanning. Results: The aforementioned technologies can all be implemented and merged into one complex treatment plan combining high predictability, successful esthetics, and a reliable and accurate end result. Even though the concept of scan flags is relatively new, this case shows its potential and merit. Conclusions: This case represents the power of the digital approach as a helpful tool in the recreation of functional and esthetic smiles in compromised conditions in periodontal patients.

Cel pracy: Celem pracy było określenie zmian czynności elektrycznej mięśni żucia u osób przyjmujących substancje psychoaktywne.Metoda: Badanie Elektromiograficzne zostało przeprowadzone za pomocą urządzenia Zebris EMG-8 Bluetooth (Zebris Medical GmbH, Niemcy). Elektrody zostały umieszczone na brzuścach mięśni żwaczy, a następnie pacjent wykonywał ruchy: lateralnie prawo/lewo, protruzyjny, zwarcie zębów, rejestracja w spoczynku oraz MVC. Następnie elektrody były umieszczane na przednich częściach m. skroniowych, a wszystkie ruchy powtórzone.Wyniki: Mięśnie w spoczynku Wzmożona aktywność elektryczna została zaobserwowana u pacjentów z grupy A w stosunku do grupy kontrolnej oprócz mięśnia żwacza po stronie prawej (RM). Ruch protruzyjny Wystąpiła wzmożona aktywność EMG wszystkich mięśni grupy A oprócz RM, lecz istotność statystyczna wystąpiła tylko dla mięśni skroniowych. Laterotruzja w prawą stronę Obie grupy pacjentów wykazały większą aktywność elektromiograficzną (A>O oprócz LM, w grupie O RM niższe nieznacznie od grupy kontrolnej) zgodną ze wzorcem skurczu dla laterotruzji. Laterotruzja w lewą stronę Podczas tego ruchu obie grupy pacjentów wykazały większą aktywność elektromiograficzną (A>O, w grupie O RM nieznacznie niższe od grupy kontrolnej) zgodną ze wzorcem skurczu dla laterotruzji.Wnioski: 1. Podczas ruchów żuchwy, w zapisie EMG stwierdzono wzmożoną czynność elektryczną mięśni żwaczy i przednich brzuśców mięśni skroniowych u osób uzależnionych od alkoholu, w porównaniu do grupy kontrolnej. 2. Podczas ruchów żuchwy, w zapisie EMG nie stwierdzono istotnej statystycznie różnicy w napięciu mięśni żwaczy i przednich brzuśców mięśni skroniowych u osób uzależnionych od opiatów, w porównaniu do grupy kontrolnej.