Rainer Lutz

Background and Clinical Significance: Removable partial dentures still present a relevant treatment option in an aging population. With the exception of clasps, the vast majority of attachment systems available for anchoring these restorations on natural abutments requires invasive tooth preparations causing secondary problems such as caries and abutment tooth fractures. In cases where an abutment tooth cannot be salvaged, placing an implant and connecting the existing prosthesis to this implant presents a viable solution. While a common path of insertion has been established during initial fabrication, it is almost impossible to match this with a newly placed retentive element. In the case presented, a novel ball anchor that allows for compensatory movements was used as a retentive implant abutment for salvaging a removable partial prosthesis. Case Presentation: An 83-year-old, medically compromised male patient, restored with a removable partial denture, stabilized by one abutment tooth and two clasps in the mandible, suffered from a non-restorable fracture of the abutment tooth. After tooth extraction, immediate implant placement (MT implant, AlfaGate, Bonn, Germany), closed healing of the implant for three month, then second-stage implant surgery and soft tissue healing for another four weeks, the implant was connected to a novel flexible attachment system, the REFLEX abutment (Hader Solutions, Dublin, Ireland). Shaped as a retentive ball, the REFLEX abutment allows lateral movements of the male attachment part while maintaining vertical dimensions like rigid locator-type attachments. Conclusions: The retrofitting of the novel flexible attachment under an originally telescopic-crown-retained partial denture allowed for a successful conversion of the prosthesis while preserving prosthetic fit and retention for the patient.

Background: The aim of this study is to investigate the potential link between the use of specific medications and oral adverse drug reactions. Methods: The 100 most frequently prescribed drugs in Germany in 2023 were compiled using the “PharMaAnalyst” database. According to the descriptions of adverse drug reactions (ADRs) in the patient information leaflets the ADRs were selected, analyzed and weighted with scores according to a classification system that distinguishes four groups of ADRs by frequency: ‘very common’ (4), ‘common’ (3), ‘uncommon’ (2) and ‘rare’ (1). The objective was to summarize the scores of the oral ADRs and define the ‘oral side effect score’ (OSES). Results: After accounting for duplication due to various brand names, 49 medications were reviewed. A total of 65% of the medications exhibited oral ADRs. The number of oral ADRs per medication ranged from one to seven. Xerostomia and dysgeusia were the most prevalent oral side effects, accounting for 37% of cases. Overall, 34% of side effects were classified as either ‘very common’ or ‘common’. The medication groups with the highest OSES were antidepressants, antibiotics and analgesics. Of the individual medications, azithromycin, gabapentin and pregabalin exhibited the highest OSES. Conclusions: This study provides a comprehensive overview of oral side effects associated with the 100 most frequently prescribed drugs. Patients with polypharmacy are particularly likely to experience oral side effects such as xerostomia and dysgeusia. Due to their high OSES combinations, antibiotics, analgesics or antidepressants may trigger multiple oral ADRs. It is essential that the medical community is continuously updated on pharmacological knowledge to raise awareness of oral ADRs.

Introduction: Our group has recently established the first ex vivo cadaveric models to simulate unilateral and bilateral cleft lip surgery. We have shown that these porcine snout disc models are suitable for novice cleft surgeons to understand the basic principles of cleft lip surgery and to practice the essential surgical steps. In this study we want to show that the ex vivo cleft lip models are not only suitable and helpful for residents, but also for students and experienced surgeons with and without experience in cleft surgery. Methods: Three courses were held to evaluate the ex vivo cleft lip models: One for oral and maxillofacial surgeons from German cleft centers and two courses for dental students. All operated on the unilateral and bilateral ex vivo cleft lip models using the Millard technique. Questionnaires were used to assess their subjective opinion of the ex vivo cleft lip models. Tasks for the students were carried out to objectify their learning success. Three-dimensional scans were taken and analyzed using a previously validated intraoral scanner to objectively assess the outcome. Results: The ex vivo cleft lip models are suitable for the training of students and experienced surgeons with varying levels of experience in cleft lip repair. Both models were rated as realistic in terms of tissue resemblance, surgical planning, and surgical management. In addition, the specialists rated the models as realistic overall. The models also provide students with several advantages, such as improved surgical skills and a better understanding of cleft surgery. Participants felt that the models should be made available not only to residents, but also to consultants and senior consultants and should be implicated in the dental curriculum. Conclusion: The ex vivo cleft lip models made of porcine snout discs are suitable for a wide range of users starting from students to experienced surgeons to train in cleft lip surgery. The great advantage of these models is that experienced surgeons can work with an inexpensive and readily available model to improve their skills and modify their techniques.

Treatment for a cleft lip can result in significant functional and aesthetic changes to the nasolabial region. Although three-dimensional (3D) measurements are the gold standard for evaluating cleft surgery, most short- and long-term evaluations still rely on subjective assessment or the measurement of patient photographs. To our knowledge, this work establishes the first baseline and reference group for the nasolabial region in children aged 3 to 9 months without cleft lip or palate. This group can be used for future evaluations, such as those of surgical outcomes or NAM therapy, via 3D anthropometric measurement. Data was collected cross-sectionally from 25 children aged 3 to 9 months using a validated intraoral scanner (Trios 4, 3Shape). Scans were analysed according to 3D anthropometric criteria by metrically accurate measurements of distances, surface curves and angles using 3D inspection software (GOM Inspect, Co. Zeiss, Jena, Germany). Results are presented as reference database combined with a step-by-step guide on the measurement methodology. For easy application all data are additionally presented in the form of formulae in which clinical data can be inserted. Based on the data from healthy children, we propose a new classification of alar base types ranging from 1 to 3. Unlike conventional assessment methods, surface curves and other 3D anthropometric tools provide a highly accurate and objective quantification of the anatomy of the nasolabial region and thus serve as a foundation for future clinical research on cleft lip surgery. Alar base type classification may influence future surgical approaches to cleft lip surgery.

Background: In order to successfully perform orthodontic mini-implant procedures successfully for the subsequent anchoring of orthodontic appliances, it is crucial to know the palatal bone thickness. This is usually assessed using two-dimensional radiographs. The purpose of this study was to use a three-dimensional digital imaging measurement method to provide information on palatal bone volume and bone thickness and to make recommendations on the optimal and safe insertion site and angle for palatal mini-implants. Methods: For this observational, cross-section study, pre-existing cone beam computed tomography scans of 184 patients were converted into 3D Standard Tessellation Language (STL) models of the maxilla. The area between the canine and the first molar was divided into 6 regions of interest (ROIs), three on the left side of the palate and three on the right side. The bone thickness of the palate was analyzed volumetrically and linearly while simulating different mini-implant insertion angles of 0°, 10°, 20° and 30° degrees relative to the palatal surface. Results: Among the ROIs, the greatest mean bone thickness was observed in the region of the first premolars with a mean distance (MD) of 10.44 ± 2.53 mm and decreased from anterior to posterior (MD: 3.44 ± 1.16 mm). The highest volume (Vol) values were also measured in the anterior palatal region (Vol: 1127.26 ± 483.91 mm³), while there was also a decrease in the posterior region (Vol: 394.36 ± 180.22 mm³). Regarding the simulated palatal mini-implant insertion sites, the greatest bone thickness was found in the anterior region, at the level of the canines with an angle of 0° (MD: 12.25 ± 3.75 mm). In the more posterior region, at the level between the first and second premolars, the greatest bone thickness was observed at an angle of 30° (MD: 7.93 ± 3.81 mm). Gender differences were found. Conclusion: This clinical study showed that the paramedian region at the level of the first premolar is the safest site for orthodontic mini-implant placement as evaluated by three-dimensional measurements. The results showed that implant insertion angle, gender and age are important aspects to consider when planning and inserting orthodontic palatal mini-implants. Trial registration: N.a.

The establishment of immunotherapy applying immune checkpoint inhibitors (ICI) has provided an important new option for the treatment of solid malignant diseases. However, different tumor entities show dramatically different responses to this therapy. BCC responds worse to anti-PD-1 ICIs as compared to cSCC. Differential immune checkpoint expression could explain this discrepancy and, therefore, the aim of this study was to analyze activating and inhibitory immune checkpoints in cSCC and BCC tissues. Tissue microarrays of the invasive front as well as the tumor core of BCC and cSCC samples were used to evaluate PD-1, PD-L1, CD28, and CD86 expression and their topographic distribution profiles by chromogenic immunohistochemistry. QuPath was used to determine the labeling index. The expression of PD-1, PD-L1, and CD28 was significantly higher in both the tumor core and the invasive front of cSCC samples as compared to BCC (p < 0.001). In addition, the ratios of PD-L1/CD86 (p < 0.001) and CD28/CD86 (p < 0.001) were significantly higher in cSCC. The invasive front of both tumor entities showed higher expression levels of all immune markers compared to the tumor core in both tumor entities. The significantly higher expression of PD-1, PD-L1, and CD28 in cSCC, along with the predominance of the inhibitory ligand PD-L1 as compared to the activating CD86 in cSCC, provide a potential explanation for the better objective response rates to anti-PD-1 immunotherapy as compared to BCC. Furthermore, the predominant site of interaction between the immune system and the tumor was within the invasive front in both tumor types.

Die radiologische Bildgebung ist in der modernen Zahnmedizin, Oralchirurgie und Mund-, Kiefer- und Gesichtschirurgie ein unverzichtbares Instrument zur Diagnose, Therapieplanung und Verlaufskontrolle einer Vielzahl von Zahn- und Kiefererkrankungen. Radiologische bildgebende Verfahren ermöglichen dem Behandler eine nicht invasive Zahn- und Kieferdiagnostik, die ihm helfen kann, Erkrankungen der Zähne, des Zahnhalteapparates und des Kiefers frühzeitig zu erkennen und Behandlungen effektiv zu planen. Der vorliegende Artikel soll dem Behandler neben einem groben Überblick über die derzeit verfügbaren Verfahren eine Handlungsempfehlung für einen sinnvollen Einsatz der bildgebenden Verfahren geben und damit auch eine optimale Behandlung der Patienten ermöglichen. Article published online: 22 August 2024 © 2024. Thieme. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

In oral squamous cell carcinoma (OSCC) tissues, an immunotolerant situation triggered by immune checkpoints (ICPs) can be observed. Immune checkpoint inhibitors (ICIs) against the PD1/PD-L axis are used with impressive success. However, the response rate is low and the development of acquired resistance to ICI treatment can be observed. Therefore, new treatment strategies especially involving immunological combination therapies need to be developed. The novel negative immune checkpoint BTLA has been suggested as a potential biomarker and target for antibody-based immunotherapy. Moreover, improved response rates could be displayed for tumor patients when antibodies directed against BTLA were used in combination with anti-PD1/PD-L1 therapies. The aim of the study was to check whether the immune checkpoint BTLA is overexpressed in OSCC tissues compared to healthy oral mucosa (NOM) and could be a potential diagnostic biomarker and immunological target in OSCC. In addition, correlation analyses with the expression of other checkpoints should clarify more precisely whether combination therapies are potentially useful for the treatment of OSCC. A total of 207 tissue samples divided into 2 groups were included in the study. The test group comprised 102 tissue samples of OSCC. Oral mucosal tissue from 105 healthy volunteers (NOM) served as the control group. The expression of two isoforms of BTLA (BTLA-1/2), as well as PD1, PD-L1/2 and CD96 was analyzed by RT-qPCR. Additionally, BTLA and CD96 proteins were detected by IHC. Expression levels were compared between the two groups, the relative differences were calculated, and statistical relevance was determined. Furthermore, the expression rates of the immune checkpoints were correlated to each other. BTLA expression was significantly increased in OSCC compared to NOM (pBTLA_1 = 0.003; pBTLA_2 = 0.0001, pIHC = 0.003). The expression of PD1, its ligands PD-L1 and PD-L2, as well as CD96, were also significantly increased in OSCC (p ≤ 0.001). There was a strong positive correlation between BTLA expression and that of the other checkpoints (p < 0.001; ρ ≥ 0.5). BTLA is overexpressed in OSCC and appears to be a relevant local immune checkpoint in OSCC. Thus, antibodies directed against BTLA could be potential candidates for immunotherapies, especially in combination with ICI against the PD1/PD-L axis and CD96.