Robert Sader

• Goethe University Frankfurt

Childhood trauma defects in the head and neck area are challenging in many aspects for patients and surgeons. One major issue is the still incomplete growth. Bone defect fixation measures have to consider biomechanical forces due to the bone growth from both sides, the bone growth possibly influencing and working against the fixation itself and vic...

Surgical treatment is often substantially based on physical parameters like restoration of the normal anatomy. But often there is no space for functional and biopsychosocial individual-related factors, which also have a huge influence on the treatment result for the patient. Overall, in the stages of several operations with concomitant fears, a net...

The alveolar ridge undergoes a loss in volume and atrophy after tooth extraction. Understanding the wound healing and bone regeneration process after tooth extraction is a key factor in the insertion of dental implants. Therefore, the aim of the present study was to analyze the socket healing process after the extraction of upper premolars based on...

The temporomandibular joint (TMJ) is one of the most complex joints in the human body, but its biomechanics has not been as extensively researched as other body joints, leading to a fundamental gap in understanding the physiological characteristics and diagnostics of related disorders. This work introduces a measurement system that applies a precis...

Background Esthetically pleasing, bright teeth and a symmetrical dental arch are of great importance. There are only a few scientific studies that compare the evaluation of anterior restorations by experts and patients. Additionally, there are hardly any studies that deal with the weighting of esthetic parameters. Objective The current study was p...

Nonmelanoma skin cancer (NMSC) presents a significant challenge to global healthcare due to its rising incidence, prompting the search for innovative treatments to overcome the limitations of current therapies. Our study aims to explore the potential effects of the liquid blood concentrate platelet-rich fibrin (PRF) on basal cell carcinoma cells (B...

Aim In treating patients with oral squamous cell carcinoma (OSCC), therapy decisions are regularly made in interdisciplinary oncologic board meetings that rely on the synopsis of clinical examinations and structured clinical imaging modalities. In many cases, postsurgical results differed from those of the initial assessment. Therefore, this study...

Background: Three-dimensional facial scan technologies, such as stereophotogrammetry, are frequently used in oral and maxillofacial surgery, dentistry, and plastic surgery to assess patient outcomes and plan surgical procedures. Most facial scanners rely on stationary clinical systems, which provide high accuracy and reliability in generating 3D re...

Objective Assess whether horizontal ridge augmentation with guided bone regeneration (GBR) using deproteinized bovine bone mineral (DBBM), autologous bone, and a resorbable collagen membrane supports successful implant placement. Materials and Methods This open, prospective, single‐cohort, multicenter clinical study included patients with ridge de...

PURPOSE The objective of the study was to analyze the impact of cement, bonding pretreatment, and ceramic abutment material on the overall color results of CAD-CAM ceramic crowns bonded to titanium-based hybrid abutments. MATERIALS AND METHODS For single implant restoration of a maxillary lateral incisor a total of 51 CAD-CAM-fabricated monolithic...

Purpose: To retrospectively evaluate the long-term clinical, technical, biological, and esthetic outcomes of implant supported single zirconia crowns (ISCs) intraorally cemented to Ti-base hybrid-abutments up to 16 years after placement. Materials and methods: A total of 63 ISCs (Xive S, Camlog Screw Line, Replace Select TC NP, Branemark MK II,...

Background Antiresorptive therapy (AR) disrupts osseous homeostasis and can induce direct irritation over the gastrointestinal mucosa; however, its possible erosive effects on the oral epithelium have not been totally described. Among the most frequent oral erosive lesions, oral lichen planus (OLP) frequently presents as painful mucosal ulcerations...

Purpose The purpose of this systematic review was to explore and identify the factors that influence the accuracy of intraoral scanning in implant dentistry, with a specific focus on scan bodies (ISBs). Methods Following the PRISMA 2020 guidelines, this study conducted a thorough electronic search across MedLine, PubMed, and Scopus to identify rel...

Platelet-rich fibrin (PRF) is a widely used autologous blood concentrate in regenerative medicine. This study aimed to characterize the cellular composition and distribution of different PRF matrices generated by high (710 g) and low (44 g) relative centrifugal forces (RCFs) and to analyze their bioactivity on human primary osteoblasts (pOBs). PRF...

The understanding that tumor cells might evade immunity through various mutations and the potential of an augmented immune system to eliminate abnormal cells led to the idea of utilizing platelet-rich fibrin (PRF), a blood concentrate containing the body’s immune elements as an adjunctive therapy for localized tumors. This study is the first that e...

Platelet-rich fibrin (PRF) has assumed an important role in supporting tissue regeneration in different fields. To date, the standard protocol for liquid PRF requires at least 10 mL of peripheral blood. The present study aimed to analyze the composition, growth factor release, and effects on the cell proliferation of PRF samples produced using 3 mL...

Blood concentrates like platelet rich fibrin (PRF) have been established as a potential autologous source of cells and growth factors with regenerative properties in the field of dentistry and regenerative medicine. To further analyze the effect of PRF on bone tissue regeneration, this study investigated the influence of liquid PRF matrices on huma...

This study aimed to compare the effectiveness of platelet-rich fibrin clot (PRF) and conventional oroantral communication (OAC) repair techniques following tooth extractions from the maxilla. The study involved 22 patients, divided into two groups: a study group treated with PRF and a control group undergoing conventional OAC repair. The primary ou...

Background/aim The aim of this study was to analyze a population of patients who had suffered from traumatic dental injuries (TDIs) by using different patient-, trauma- and treatment-related parameters. Material and methods All dental records of patients ≥ 3 years old who had presented at the dental emergency service between Jan 1, 2009 and Dec 31...

Human dental pulp stem cells (DPSCs) exhibit multilineage differentiation capabilities and superior clonogenic and proliferative properties. However, the use of animal-derived components such as FBS raises concerns regarding the clinical application of stem-cell-based therapies. Platelet-rich fibrin (PRF) derived from human blood is rich in fibrin,...

Objectives: The consecutive case series accesses the results and experiences of ridge augmentation using an umbrella-screw (US) tenting technique. Materials and methods: 279 patients have been treated between 05/26/2015 and 08/16/2021 including horizontal and vertical ridge defects. Gender, age, smoking behavior, jaw, graft material, soft tissue t...

The concept of extraction socket healing has been severally researched and reported over the years, since tooth extraction remains one of the most common procedures performed in the dental clinic. Understanding this healing process is of utmost importance because the outcome has a direct bearing on future prosthetic rehabilitation and, by extension...

The concept of extraction socket healing has been severally researched and reported over the years, since tooth extraction remains one of the most common procedures performed in the dental clinic. Understanding this healing process is of utmost importance because the outcome has a direct bearing on future prosthetic rehabilitation and, by extension...

Narrow-diameter implants (NDIs) can be inserted instead of standard dental implants (SDIs) in sites with limited space and bone availability. The aim of this study was to evaluate the effect of implant diameter on peri-implant bone, attached mucosa, and on the associated probability of implant success and survival. The implants with progressive thr...

During the present study, an in vitro coculture bone tissue mimic based on primary osteoblasts and primary endothelial cells was used for a complex and broad evaluation of a newly developed material for applications in pediatric maxillofacial traumatology. The biomaterial was composed of PDLLA (poly(D,L-lactide)) in various combinations with calciu...

IntroductionThe aim of the study was to evaluate the accuracy of MRI and CT with regard to the detection of lymph node metastases based on the data of specific patients with OSCC who received bilateral neck dissection.Materials and methodsIn a retrospective analysis from 01/2014 to 12/2020 patients who underwent primary tumor resection and bilatera...

Objectives To investigate the extension of experimentally induced peri-implantitis lesions under various antiresorptive and antiangiogenic medications. Material and methods Fourty-eight albino rats had randomly received the following medications (dual application, n = 8 each): (1) amino-bisphosphonate (zoledronate) (Zo), (2) RANKL inhibitor (denos...

Objective Tumor resection and reconstruction in patients with oral squamous cell carcinoma often involves free flaps followed by radiation therapy. Volume loss of free flaps is common following transplantation and radiation therapy. Therefore, this study investigates the volume loss of free radial forearm flaps in the field of craniomaxillofacial s...

Purpose Oropharyngeal dysphagia is one of the most common postoperative consequences in head and neck cancer patients. Above all, these patients often suffer from aspiration and limitations of oral intake. However, no reliable dysphagia screening is available for this target group. This study aimed to develop and validate a screening, FraMaDySc, ba...

Purpose: To assess the clinical performance of a two-piece zirconia implant system (PURE Ceramic Implants, Straumann, Basel, Switzerland) in the maxilla after a follow-up period of more than 1 year. Materials and methods: A total of 19 patients in three centres received 24 single-tooth implants in the maxilla. The implants were restored after a...

Background: The ongoing changes in learning and education towards digitalisation have been rapidly accelerated by the COVID-19 pandemic. Especially in dental education where contact to the oral cavity is an integral part of training the chosen digital examination methods and training formats must undergo high requirements to full fill the goal of...

Systematic evaluations regarding the influence of PRF in ridge sealing are still lacking. To the best of our knowledge, this is the first systemic randomized, controlled, clinical approach dealing with the potential of a systematic applied solid PRF on soft tissue socket healing of molar and premolar extraction sockets with evaluation for up to 90...

Purpose: Computer-aided design and manufacturing (CAD-CAM) of implant abutments has been shown to result in surface contamination from site-specific milling and fabrication processes. If not removed, these contaminants can have a potentially adverse effect and may trigger inflammatory responses of the peri-implant tissues. The aim of the present s...

Zusammenfassung Hintergrund Patienten mit einem Kopf-Hals-Tumor besitzen ein hohes Risiko, peri- bzw. posttherapeutisch eine Mangelernährung zu entwickeln, die den onkologischen Therapieerfolg entscheidend beeinflussen kann. Prätherapeutisch ist hierüber wenig bekannt. Daher ist das Ziel der vorliegenden Studie die prätherapeutische systematische E...

Objective Tumor resection and reconstruction in patients with oral squamous cell carcinoma often involves free flaps followed by radiation therapy. Volume loss of free flaps is common following transplantation and radiation therapy. Therefore, this study investigates the volume loss of free radial forearm flaps in the field of craniomaxillo- facial...

Introduction: Treatment of extended defects after tumor resection in oral, maxillofacial, and facial surgery (craniomaxillofacial) is usually performed by free microvascular flaps. Evaluation of flap survival is crucial, especially in the first hours after insertion and connection. For flap evaluation various invasive and noninvasive methods have b...

Introduction: Treatment of extended defects after tumor resection in oral, maxillofacial, and facial surgery (craniomaxillofacial) is usually performed by free microvascular flaps. Evaluation of flap survival is crucial, especially in the first hours after insertion and connection. For flap evaluation various invasive and noninvasive methods have...

AimThe primary aim of this study was to analyze frequency and characteristics of combined facial and peripheral trauma with consecutive hospitalization and treatment.Materials and methodsThe study included all patients with concomitant orthopedic-traumatolgical (OT) and craniomaxillofacial (CMF) injuries admitted to our level I trauma center in 201...

The combination of histological and biomolecular analyses provides deep understanding of different biological processes and is of high interest for basic and applied research. However, the available analytical methods are still limited, especially when considering bone samples. This study compared different fixation media to identify a sufficient a...

Objectives: To assess the literature on (i) the relevance of the presence of a minimum dimension of keratinized peri-implant mucosa (KPIM) to maintain the health and stability of peri-implant tissues, and; (ii) the surgical interventions and grafting materials used for augmenting the dimensions of the KPIM when there is a minimal amount or absence...

Aim: To evaluate the influence of the width of keratinized tissue (KT) on the prevalence of peri-implant diseases, and soft- and hard-tissue stability. Materials and methods: Clinical studies reporting on the prevalence of peri-implant diseases (primary outcome), plaque index (PI), modified plaque index (mPI), bleeding index (mBI), bleeding on p...

Introduction Tumor resection combined with neck dissection (ND) or radiotherapy are established methods for the treatment of patients with oral squamous cell carcinoma (OSCC). However, the extent of ND can lead to postoperative complications. Therefore, for the first time, this study aims to identify lymph node involvement in OSCC performed in a bi...

Purpose To retrospectively compare the high-angled sagittal split osteotomy (HOO) and the bilateral sagittal split osteotomy (BSSO) for the correction of skeletal dysgnathias regarding intra- and postoperative complications. Methods The electronic medical records of all patients treated with an orthognathic surgery at the Department for Oral, Maxi...

Zusammenfassung Hintergrund Patienten mit einem Kopf-Hals-Tumor besitzen ein hohes Risiko, peri- bzw. posttherapeutisch eine Mangelernährung zu entwickeln, die den onkologischen Therapieerfolg entscheidend beeinflussen kann. Prätherapeutisch ist hierüber wenig bekannt. Daher ist das Ziel der vorliegenden Studie die prätherapeutische systematische E...

Objective The aim of this study was to retrospectively review the midface and orbital floor fractures treated at our institution with regard to epidemiological aspects, surgical treatment options and postoperative complications and discuss this data with the current literature. Study design One thousand five hundred and ninety-four patients with m...

Objectives: To assess and compare the efficacy and safety of autogenous tooth roots (TRs) and autogenous bone blocks (ABs) for combined vertical and horizontal alveolar ridge augmentation and two-stage implant placement. Materials and methods: A total of 28 patients in need of implant therapy and vertical ridge augmentation were allocated to par...

Objectives There is no information today about the impact of abutment type on the crestal bone stability. This retrospective study was aimed to evaluate the crestal bone levels (CBL) and failures of implants with prefabricated and customized abutments after the long term.Materials and methodsThe mesial and distal CBL around dental implants with pre...

Zusammenfassung Hintergrund Sowohl der Schluck- als auch der Ernährungsstatus bei Kopf-Hals-Tumor(KHT)-Patienten nach einer onkologischen Therapie sind gut untersucht. Prätherapeutisch werden sie aber selten thematisiert, obwohl diese den Erfolg einer onkologischen Therapie nachhaltig beeinflussen können. Ziel der Arbeit Ziel dieser Arbeit ist di...

Objectives A conometric concept was recently introduced in which conical implant abutments hold the matching crown copings by friction alone, eliminating the need for cement or screws. The aim of this in vitro study was to assess the presence of microgap formation and bacterial leakage at the Acuris conometric restorative interface of three differe...

Esthetic complications in implant dentistry have become a significant consideration for patients and practitioners. This review presents an appraisal on the current knowledge of the physiological peri‐implant soft‐tissue dimensions and factors that may compromise peri‐implant tissue esthetics. Factors such as papilla fill adjacent to the implant an...

Evaporation of phosphate species during thermal treatment (> 400°C) of calcium phosphates leads to the formation of an alkaline layer on their surface. The aim of this study was to evaluate the hypothe- sis that the biological response of thermally treated calcium phosphates is modified by the presence of such an alkaline layer on their surface. Fo...

Introduction: The diagnosis and therapy of oral squamous cell carcinoma (OSCC) in Germany is according to guidelines and relies on interdisciplinary board meetings. Standard examination techniques are computed tomography (CT) and magnet resonance imaging (MRI). These technologies are used as objective tools for serial presentation in an oncologic...

Background The treatment of carious lesions is one of the most fundamental competencies in daily dental practice. However, many commercially available training models lack in reality regarding the simulation of pathologies such as carious lesions. 3D printed models could provide a more realistic simulation. This study provides an exemplary descript...

Background To evaluate peri-implant tissue dimensions following implantoplasty and/or regenerative therapy of advanced ligature-induced peri-implantitis in dogs. Material and methods At all defect sites ( n = 6 dogs, n = 48 implants), the intrabony component was filled with a particulate bovine-derived natural bone mineral (NBM). The supracrestal...

Objectives To assess the influence of antiresorptive/antiangiogenic therapy on the spreading of peri-implant infections in the pharyngeal region. Material and methods This analysis was based on tissue biopsies obtained from a total of twenty-five albino rats having either received (1) amino-bisphosphonate (Zoledronate) (Zo) ( n =4), (2) RANKL inhi...

Purpose To address the focused question: in patients with freshly extracted teeth, what is the efficacy of platelet-rich fibrin (PRF) in the prevention of pain and the regeneration of soft tissue and bone compared to the respective control without PRF treatment? Methods After an electronic data search in PubMed database, the Web of Knowledge of Th...

Due to the coronavirus pandemia, dental schools are facing a change onto virtual solutions. Teledentistry has proven to be an opportunity to bridge this gap. This study aims to assess the feasibility and acceptance of a virtual dental examination. It took place during the final maxillofacial examination. Study participants were dental students and...

Platelet rich fibrin (PRF) is an autologous blood concentrate, that supports tissue regeneration. The effect of the centrifuge rotor angle in the fabrication of PRF is still not fully elucidated. The hypothesis of this study is: When applying the same g-force {relative centrifugal force (RCF)} and centrifugation time, PRF components and bioactivity...

Multinucleated giant cells (MNGCs) are frequently observed in the implantation areas of different biomaterials. The main aim of the present study was to analyze the long-term polarization pattern of the pro- and anti-inflammatory phenotypes of macrophages and MNGCs for 180 days to better understand their role in the success or failure of biomateria...

Purpose: The objective of this investigation was to assess the extent of mucosal discoloration caused by different CAD/CAM abutment materials and to determine the influence of mucosa thickness on the subsequent color, with a particular focus on titanium nitride. Materials and methods: In a pig maxilla, a trapdoor-shaped mucosa flap was prepared...

Zusammenfassung Hintergrund Dysphagie bildet eine häufige postoperative Funktionsbeeinträchtigung bei Kopf-Hals-Tumorpatienten. Diese kann in Aspiration bzw. Penetration sowie Oralisierungseinschränkung resultieren und ist dadurch häufig versorgungsrelevant. In dieser Studie wurden die Prävalenz einer postoperativen Dysphagie und der Zusammenhang z...

Sulfated glycosaminoglycans (sGAG) show interaction with biological mediator proteins. Although collagen-based biomaterials are widely used in clinics, their combination with high-sulfated hyaluronan (sHA3) is unexplored. This study aims to functionalize a collagen-based scaffold (Mucograft®) with sHA3 via electrostatic (sHA3/PBS) or covalent bindi...

Background The high-oblique sagittal osteotomy (HOSO) is an alternative to a bilateral sagittal split osteotomy (BSSO). Due to its novelty, there are no long-term studies which have focused on describing the incidence and type of complications encountered in the post-operative follow-up. The aim of this retrospective study is to analyze patients op...

Introduction: E-Scooters are trending as an individual transport vehicle with electric drive in Germany. But there is less data about the frequency, demographic details and possible injuries and therapy needs in context with E-scooter accidents. Therefore, the primary aim of this study was to analyze the frequency and the characteristics of facial...

Objectives: To immunohistochemically characterize and correlate macrophage M1/M2 polarization status with disease severity at peri-implantitis sites. Materials and methods: A total of twenty patients (n = 20 implants) diagnosed with peri-implantitis (i.e., bleeding on probing with or without suppuration, probing depths ≥ 6 mm, and radiographic m...

COVER ILLUSTRATION: The cover image is based on the Original Article Assessment of soft and hard tissue dimensions following different treatment approaches of ligature‐induced peri‐implantitis defects by Ausra Ramanauskaite et al., https://doi.org/10.1111/clr.13709.

Background The correct performance of a structured facial examination presents a fundamental clinical skill to detect facial pathologies. However, many students are not adequately prepared in this basic clinical skill. Many argue that the traditional ‘See One, Do One’ approach is not sufficient to fully master a clinical skill. ‘Mental Training’ ha...

Objectives The aim of the present study was to characterize the cellular reaction to a xenogeneic resorbable collagen membrane of porcine origin using a subcutaneous implantation model in Wistar rats over 30 days.Materials and methodsEx vivo, liquid platelet-rich fibrin (PRF), a leukocyte and platelet-rich cell suspension, was used to evaluate the...

Objectives To evaluate the prevalence of peri‐implant health, peri‐implant mucositis or peri‐implantitis for subcrestally placed implants (1‐3 mm) on the short‐, medium‐ and long‐term. Material & Methods Two hundred patients were enrolled in this cross‐sectional study that were treated and screened during regular maintenance visits at one universi...

Introduction: Resorbable synthetic scaffolds are promising for different indications, especially in the context of bone regeneration. However, they require additional biological components to enhance their osteogenic potential. In addition to different cell types, autologous blood-derived matrices offer many advantages to enhance the regenerative c...

Objectives To evaluate peri‐implant tissue dimensions following non‐surgical (NS) and surgical therapy (S) employing different decontamination protocols of advanced ligature‐induced peri‐implantitis in dogs. Material & Methods Peri‐implantitis defects (n=5 dogs, n=30 implants) were randomly and equally allocated in a split‐mouth design to NS or S...

Purpose: To assess the prevalence of peri-implant diseases (ie, peri-implant mucositis and peri-implantitis) in patients rehabilitated with full-arch, implant-supported restorations. Materials and methods: A search protocol was developed to answer the following focus question: What is the prevalence of peri-implant diseases in edentulous patient...

The tasks of Working Groups 1 to 6 at the 4th Consensus Meeting of the Oral Reconstruction Foundation were to elucidate clinical recommendations for implant-supported full-arch rehabilitations in edentulous patients. Six systematic/narrative reviews were prepared to address the following subtopics: (1) the influence of medical and geriatric factors...

Zur Augmentation atrophierter Kieferkämme wurden über die Jahre eine Vielzahl an Operationstechniken vorgestellt. Gemeinsames Ziel aller vorgestellten Methoden war es, ein ausreichendes Knochenvolumen für eine prothetisch orientierte Implantatposition zu generieren. Für keine dieser Methoden lag ausreiche Evidenz vor, einer anderen Technik überlege...

Evaporation of phosphate species during thermal treatment (> 400 °C) of calcium phosphates leads to the formation of an alkaline layer on their surface. The aim of this study was to evaluate the hypothesis that the biological response of thermally treated calcium phosphates is modified by the presence of such an alkaline layer on their surface. For...

Abstract Background The feedback given to students plays an important role in their efficiency related to learning practical skills. In the present study, diverse feedback modalities have been investigated. Our hypothesis is that individualized and unsupervised video feedback can produce a similar learning experience as performing practical skills...

Objective To assess the influence of biphasic calcium phosphate materials with different surface topographies on bone formation and osseointegration of titanium implants in standardized alveolar ridge defects. Materials and methods Standardized alveolar ridge defects (6 × 6 mm) were created in the mandible of 8 minipigs and filled with three bipha...

Aim This computational study aimed to evaluate the influence of the angle of the osteotomy when performing a high oblique sagittal osteotomy over the distribution of stress to the osteosynthesis plates and mandibular segments. Material and methods: For this purpose, a finite element analysis of different combinations was carried out based on the os...

In vitro tissue engineered cell culture models are an essential instrument to investigate physiological and pathophysiological wound healing mechanisms and to evaluate new beneficial wound dressing materials and therapeutics to identify possible drug targets and to improve regeneration processes in non-healing and chronic wounds. In this study, the...