Constantinus Politis

• MD,DDS,MHA,MM,EBOMFS,PhD
• Professor (Full) at Universitair Ziekenhuis Leuven

This study aims to evaluate and compare the usability and performance of mixed reality (MR) technology versus conventional methods for preoperative planning of patient-specific reconstruction plates for orbital fractures. A crossover study design was used to compare MR technology with conventional three-dimensional (3D) printing approaches in the p...

Condylar resorption is a feared complication of orthognathic surgery. This study investigated condylar resorption in a cohort of 200 patients This allowed for a powerful update on incidence and risk factors. 9.5% of patients developed resorption. These patients had on average, 17% volume loss with 3.9 mm ramal height loss and 3.1 mm posterior mandi...

Background: Mandibular condyle fractures in pediatric patients can lead to crippling sequelae such as ankylosis, pain and facial deformity if not managed properly. However, there is no consensus on the best approach for treating these fractures in children. Objective: This study aimed to describe the management of mandibular condyle fractures in gr...

Background/aim Paediatric maxillozygomatic complex (MZC) fractures are uncommon, and there is a scarcity of data regarding their surgical treatment. The aim of this study was to analyse choices and outcomes of open reduction and internal fixation (ORIF) for MZC fractures among 14 maxillofacial centers around the world. Materials and Methods This m...

The conventional method to reconstruct the bone level for orbital defects, which is based on mirroring and manual adaptation, is time-consuming and the accuracy highly depends on the expertise of the clinical engineer. The aim of this study is to propose and evaluate an automated reconstruction method utilizing a Gaussian process morphable model (G...

The purpose of this study was to report root remodeling/resorption percentages of maxillary teeth following the different maxillary osteotomies; i.e. one-piece, two-pieces, three-pieces Le Fort I, surgically assisted rapid palatal expansion (SARPE). The possibility of relationships between root remodeling and various patient- and/or treatment-relat...

Three-dimensional soft tissue simulation has become a popular tool in the process of virtual orthognathic surgery planning and patient–surgeon communication. To apply 3D soft tissue simulation software in routine clinical practice, both qualitative and quantitative validation of its accuracy are required. The objective of this study was to systemat...

Purpose The training and preferences of surgeons influence the type of surgical treatment for mandibular fractures. This multicentre prospective study analyzed the current treatment strategies and outcomes for mandibular fractures with open reduction and internal fixation (ORIF). Material and Methods This prospective study included patients aged ≥...

There are several treatment options to treat a class II dentofacial deformity with a pronounced chin. A total subapical osteotomy is one of these options. This type of osteotomy was refined to total subapical and ramus (TSAR) osteotomy. In this technical note, a detailed and schematic presentation of the TSAR osteotomy is presented step by step....

Objectives The present study aims to quantitatively assess secondary alveolar bone graft (SABG) resorption in unilateral cleft lip, alveolus and palate (UCLAP) patients in a 2–3 year longitudinal follow‐up setting by using a validated 3D protocol. Furthermore, the potential relation of SABG resorption with maxillary canine position and a number of...

Objectives: To provide a critical update identifying the knowledge gaps and controversies in medication-related osteonecrosis of the jaw (MRONJ) within the Belgian healthcare context and outline opportunities for improvement and research in these areas. Methods: A literature review was performed to identify guidelines from international clinical so...

Objectives MR neurography has the ability to detect and depict peripheral nerve injuries. This study evaluated the potential of MR neurography in the diagnosis of post-traumatic trigeminal neuropathy. Methods Forty-one participants prospectively underwent MR neurography of the lingual and inferior alveolar nerves using a 3D TSE STIR black-blood...

The aim of this study was to assess the morphological characteristics of the coronoid process (CP) and define coronoid hyperplasia (CH) using cadaveric mandibles of a Caucasian population. A sample of 151 adult dry cadaveric mandibles (302 CPs) was acquired. Three distances were measured, which included the width, height, and length of CP. The surf...

This chapter is focused on radiobiological aspects at the molecular, cellular, and tissue level which are relevant for the clinical use of ionizing radiation (IR) in cancer therapy. For radiation oncology, it is critical to find a balance, i.e., the therapeutic window, between the probability of tumor control and the probability of side effects cau...

Background Optimization of dental cone beam computed tomography (CBCT) imaging is still in a preliminary stage and should be addressed using task‐based methods. Dedicated models containing relevant clinical tasks for image quality studies have yet to be developed. Purpose To present a methodology to develop and validate a virtual adult anthropomor...

Objectives: To investigate whether variations in head positioning may influence the reproducibility of cone-beam CT (CBCT) three-dimensional (3D) segmented models of the mandibular condyle. Methods: Five fresh frozen cadaver heads were scanned in four different positions: reference position (RP) and a set of three tilted alternative head position...

Purpose The sphenoid bone (SB) extracranial ligaments (ECRLs) are the pterygoalar and pterygospinous ligaments (PTAL and PTSL) that are located at the SB lateral pterygoid plate, and inferior to the foramen ovale (FO). Their ossification may affect the mandibular nerve’s distribution. The intracranial ligaments’ (ICRLs) ossification (the caroticocl...

Depending on the diagnostic modality, the classification of vascular anomalies varies and so does the nomenclature. The ‘International Society for the Study of Vascular Anomalies’ (ISSVA) is the most widely accepted classification in the literature and is mainly based on the radiologic and clinical presentation. The aim of this article is to review...

Introduction: This study aims to compare the surgical and clinical complications, and the dental implant survival rate after maxillary sinus floor augmentation using demineralized freeze-dried bone allografts (DFDBA) versus bovine derived xenografts. Material and methods: A retrospective study enrolled 107 patients (52 males and 55 females, mean...

Background For patients with a maxillary transversal deficiency (MTD), various treatment options are available, partly based on the practitioner’s experience. This study aimed to determine a cut-off age for decision making between surgically assisted rapid palatal expansion (SARPE) over orthodontic rapid palatal expansion (ORPE) based on skeletal m...

Aims: The aim of this presentation is to discuss associations between aetiologies, fracture types, and neurological complications. Additionally, treatment methods in relation to the recovery time will be discussed. Materials and Methods: Medical files and radiological files of 272 patients with unilateral and bilateral ZMC fractures were reviewed,...

The aim was to present expert-based guidelines on the management of trigeminal nerve injuries. A two-round multidisciplinary Delphi study was conducted amongst international trigeminal nerve injury experts with a set of statements and three summary flowcharts using a nine-point Likert scale (1 = strongly disagree; 9 = strongly agree). An item was d...

Quantitative sensory testing (QST) is a valuable tool in the assessment of orofacial somatosensory function and dysfunction. QST is a method where thermal and mechanical stimuli are applied to the area of interest in a noninvasive way. The QST technique can detect patterns of loss of sensation that may happen in case of hypoesthesia, hypoalgesia, a...

Objectives: Dentists and oral surgeons often face difficulties distinguishing between radicular cysts and periapical granulomas on panoramic imaging. Radicular cysts require surgical removal while root canal treatment is the first-line treatment for periapical granulomas. Therefore, an automated tool to aid clinical decision making is needed. Met...

Autoimmune diseases result from the immune system attacking native cells and tissues due to the recognition of "self" antigens as foreign antigens. This group of disorders is associated with an increased risk of complications after surgical interventions, as the immune system may cause tissue destruction. The study aimed to investigate the risk of...

Pleomorphic adenomas present as a slow-growing, well-defined, painless nodular masses. Histopathological examination is necessary when a hard mass is found in the lip. Long follow-up is important because late malignant conversion is possible.

A 6-year-old girl presented with a grossly expansive lesion of the left lower jaw. Radiological investigations revealed a large mixed radiolucent/radio-opaque lesion of the left mandible extending into the ramus. Correlation of biopsy and imaging results lead to the diagnosis of an expansile form of focal cemento-osseous dysplasia. Surgical enuclea...

Purpose: Intraoperative stabilisation of bony fragments with maxillo-mandibular fixation (MMF) is an essential step in the surgical treatment of mandibular fractures that are treated with open reduction and internal fixation (ORIF). The MMF can be performed with or without wire-based methods, rigid or manual MMF, respectively. The aim of this stud...

Objective: We analyzed the complication rates and outcomes in patients with gastrointestinal disorders who had undergone maxillofacial surgery. Study design: We retrospectively analyzed 289 patients with inflammatory bowel disease (IBD), 142 with gastroesophageal reflux disease (GERD), and 42 with celiac disease (452 total) who had undergone ora...

The aim of this study was to better characterize head and neck solitary fibrous tumors (SFTs) and to evaluate surgical treatment. This retrospective study included patients who presented with head and neck SFTs. Clinical, radiological, and histological information and data regarding the treatments performed were collected. The risk of locoregional...

Purpose: To propose diffuse osteomyelitis as risk indicator for peri-implantitis following the loss of several dental implants in patients that present with highly sclerotic bone areas. Materials and methods: A total of six "nightmare cases"-three of which were treated at the Department of Periodontology of the University Hospitals of the Cathol...

PurposeOdontogenic keratocysts (OKCs) have high recurrence rates. We aimed to identify recurrence patterns in OKCs and the onset of second primary OKCs in non-syndromic and syndromic patients.Material and Methods Patients with OKCs reporting to our department from 1998 to 2021 (23 years) were retrospectively evaluated using demographic, clinical (a...

Introduction Quantitative sensory testing (QST) is a valuable tool in the assessment of orofacial somatosensory dysfunction. Normal values have already been recorded for some parts of the face and mouth, but not for the complete innervation area of the trigeminal nerve. The aim of this pilot study is to inform a large-scale clinical trial generatin...

The odontogenic keratocyst (OKC) is a common cystic lesion in the jaw. Its management, however, is highly debated with no consensus on the best treatment option. Clinicians base their approach on treatment efficacy and associated morbidity. Management often consists of enucleation with peripheral ostectomy and adjunctive therapy to prevent recurren...

Ameloblastomas are benign, mostly intra-osseous, tumours originating from ectodermal odontogenic epithelium and display extracellular matrix remodelling. We determined whether fibroblast activation protein-alpha (FAP-alpha), a collagenolytic enzyme and lysyl oxidase (LOX), a collagen cross-linker were differentially regulated in ameloblastoma subty...

The risk of insertion trauma in cochlear implantation is determined by the interplay between individual cochlear anatomy and electrode insertion mechanics. Whereas patient anatomy cannot be changed, new surgical techniques, devices for cochlear monitoring, drugs, and electrode array designs are continuously being developed and tested, to optimize t...

Biocompatibility and osteoconductivity of porous scaffolds can be improved through coating technique by creating micro- and nanostructures on the surfaces. In this study, a biomimetic approach was used to construct a bone morphogenetic protein-2 (BMP-2) integrated calcium phosphate (CaP) coating on the surface of porous titanium scaffolds. In vitro...

This study investigated the incidence, risk factors, and outcome of medication-related osteonecrosis of the jaw after dental extractions in patients receiving antiresorptive agents for osteoporosis or bone metastases. 240 patients with a median drug exposure of 43 months were retrospectively studied. The incidence of MRONJ after dental extraction i...

De mon dzo rg kan en moet effici ënter 13 CONSULLEEUW De Complexite it de r Incompetente Ken nis en Kunde 14 CONSULPRAKTIJK Duurzaam heid: "Gewoon stap voo r stap beginnen " 19 CONSULINFO Agenda VBT 20 CONSULPRAKTIJK CONSULEVENEMENT 'Als je denkt HiJh71, dan is de grens bereikt' VBT-co ngres over Pij n en Tra uma 27 CONSULBEELD Molar Tooth Sign 31...

Objectives Our aim was to determine the accuracy of the three-dimensional (3D) virtual planning and stability of LeFort I osteotomy in cleft lip and/or palate patients (CLP) using a validated 3D method. Materials and methods Eight patients with a history of cleft lip/palate treated with LeFort I osteotomy for maxillary hypoplasia between January 2...

With the advent of biodegradable osteosynthesis material, titanium osteosynthesis for ORIF in pediatric maxillofacial trauma is not as indisputable as before. The aim of this study was to conduct a scoping review to assess the indications, complications of ORIF with titanium osteosynthesis material in pediatric maxillofacial trauma. A systematic se...

Radiation doses in dentomaxillofacial imaging are typically very low. However, diagnostic and follow-up protocols in orthognathic surgery result in a patient-specific risk in effective dose. Estimating the cancer risks from these exposures remains abstract for many maxillofacial surgeons. In this study, 40 orthognathic patients were randomly sample...

Peripheral facial nerve palsy (PFP) is a rare occurrence after dental extraction. Early onset PFP after the procedure can be caused by trauma and/or local anesthesia, whereas delayed onset PFP has more speculative etiologies. The latter has a certain affiliation to Bell's palsy and is therefore primordially treated with corticosteroids and long-ter...

Background: Lack of evidence exists related to the incidence of postoperative complications in asthmatic patients following orthognathic surgery. The present study aimed to assess the incidence and risk factors of postoperative complications in asthmatic patients following orthognathic surgery. Material and methods: A retrospective cohort study...

Many different disciplines are involved in the diagnosis and treatment of vascular anomalies. Although clear communication is paramount in a multidisciplinary approach, different classification systems and nomenclatures are still used today. The ‘International Society for the Study of Vascular Anomalies’ (ISSVA) is the classification most accepted...

Most commonly used orthognathic surgery procedures have been used for more than 50 years following a typical planning protocol. The main aim of these procedures is to displace the maxilla or mandible (mono-maxillary approach) or both (bimaxillary approach) into another position to correct maxillofacial deformities. The planning process for bimaxill...

Objectives: To report on zygomatic implant (ZI) survival rate and associated complications through a longitudinal retrospective cohort assessment. Material and methods: A total of 940 ZIs (rough: 781, machined: 159; immediate loading: 454, delayed loading: 486) and 451 standard implants (rough: 195, machined: 256; immediate loading: 58, delayed...

Purpose To estimate the prevalence of the sphenoidal emissary foramina (SEF), and the effect of possible moderators on it. Methods A systematic online literature search was conducted. The pooled prevalence with 95% confidence intervals was estimated. Outlier and influential analyses were performed. The presence of small-study effect and publicatio...

Purpose Implant-supported prosthetic rehabilitation in the resorbed maxilla is a great challenge. The aim of this study was to determine the survival rate of conventional anterior implants placed in combination with zygomatic implants according to the Brånemark technique, and to identify risk factors for implant failure. Methods We collected data...

Introduction: The goal of mandibular fracture treatment is to restore static and dynamic occlusal functions. Open reduction and internal fixation (ORIF) of these fractures can be associated with an intraoperative and/or postoperative maxillo-mandibular fixation (MMF). The aim of this study was to analyse the use of perioperative MMF and its effect...

Purpose This study aimed to investigate the performance of novice versus experienced practitioners for placing dental implant using freehand, static guided and dynamic navigation approaches. Methods A total of 72 implants were placed in 36 simulation models. Three experienced and three novice practitioners were recruited for performing the osteoto...

Objective: The purpose of this study was to describe the complications following orthognathic surgery in patients with rheumatic diseases and to evaluate rheumatic disease as a possible risk factor. Methods: A retrospective cohort study was conducted during a 6-year period. The sample consisted of rheumatic and healthy patients who underwent ort...

Machine learning risk prediction of mortality for patients undergoing surgery with perioperative SARS-CoV-2: the COVIDSurg mortality score

'Stomatologie en MKA'wordt in Vlaanderen ingekort tot'MKA'wat staat voor mond-, kaak- en aangezichtschirurgie. Meteen is duidelijk dat deze medische discipline zich specialiseert in de behandeling van een bepaalde regio van het menselijk lichaam. Een stand van zaken van dit vakgebied.

Background: While sexuality and intimacy are suggested to contribute to quality of life (QoL), it is striking that the sexual problems of head and neck cancer patients have not been adequately studied. Objectives: Our aim was to prospectively assess the impact of head and neck cancer and its treatment on sexuality and intimacy. Material and met...

Objective : Three-dimensional (3D) quantitative assessment of external root resorption (ERR) following combined orthodontic-orthognathic surgical treatment is vital for ensuring an optimal long-term tooth prognosis. In this era, lack of evidence exists applying automated 3D approaches for assessing ERR. Therefore, this study aimed to validate a pro...

Additive manufacturing offers a revolutionary pathway for customising patient-specific metal implants. However, clinical practice calls for balanced material properties besides a patient-matched geometry, including good biocompatibility, low elastic modulus, good material strength and enhanced wear resistance. This study demonstrates an in-situ mic...

Een gecarieerde 4 7 diep geïmpacteerd AUTEURS PROF. DR. CONSTANTINUS POLITIS EN DR. RUXANDRA COROPCIUC, DIENST MKA UZ LEUVEN Een 36-jarige patiënte met pijn ter hoogte van een gecarieerde, maar geïmpacteerde 47 wordt verwezen voor een extractie. De pati-ente brengt een rx opg mee zodat er 'geen nieuwe nodig is' (figuur 1). De huidige terugbetalings...

Additive manufacturing has received tremendous attention in the manufacturing and materials industry in the past three decades. Zirconia-based advanced ceramics have been the subject of substantial interest related to structural and functional ceramics. NanoParticle Jetting (NPJ), a novel material jetting process for selectively depositing nanopart...

The application of three dimensional (3D) printed patient specific cutting guide for biopsy of a mandibular lesion closely positioned to the mandibular canal is presented. To prevent inferior alveolar nerve damage, the cutting site of the bone window was virtually planned and then the cutting guide was 3D printed. This guide enabled intra-operative...

Objectives Non-neoplastic salivary gland diseases are rare in children. This paper aims to present the spectrum of encountered non-neoplastic salivary gland diseases at a tertiary center by describing the demographics, clinical characteristics, and outcomes in this patient population. Methods A review of electronic medical records was performed fr...

Since the outbreak of COVID-19 pandemic, maintaining safety in dental operations has challenged health care providers and policy makers. Studies on dental aerosols often focus on bacterial viability or particle size measurements inside dental offices during and after dental procedures, which limits their conclusions to specific cases. Fundamental u...

Aim The present aim was to estimate direct health care costs of patients suffering from post-traumatic trigeminal neuropathy (PTTN) and to compare the use of health care services, medications, and costs between temporary and persistent (>3 months) PTTN cohorts. Methods A pre-existing clinical dataset of PTTN patients visiting a tertiary orofacial...

Objective This systematic review aims to investigate the effect of virtual planning on the treatment of zygomaticomaxillary complex (ZMC) traumatology followed by intraoperative navigation. Furthermore, clinical outcomes following intraoperative navigation surgery or conventional surgery will be compared. Materials and methods A systematic literat...

Treatment of mandibular coronoid process hyperplasia (MCPH) has been described and explored in the literature. This systematic review aims to provide a comprehensive overview of the surgical and non-surgical treatment options for MCPH in pediatric and adult populations. Three databases were searched for treatment of MCPH patients (MEDLINE, Embase,...

Temperature-responsive hydrogels exhibit great potentials to encapsulate cells for 3D bioprinting and tissue engineering applications; however, cell aggregation and the hydrogel stiffness determine cell fate and limit its application. Here, we developed a new temperature-responsive hydrogel with interpenetrating polymer networks using poly (N-isopr...

The potential impact of systemic comorbidities has not yet been thoroughly explored in orthognathic surgery. Therefore, the following scoping review was conducted to accumulate evidence on the possible impact of systemic comorbidities on the orthognathic surgery complications. PubMed, Embase, Cochrane, and Web of Science databases were searched up...

Objective: Firstly, this review aims to analyse the recent literature about three-dimensional (3D) diagnostic imaging in complex and compound odontomas and compare it to two-dimensional (2D) imaging. Panoramic radiographs help to evaluate the vertical position of odontomas, and occlusal radiographs are used to evaluate the proximity to adjacent tee...

Aim This study aims to explore the prevalence of Iatrogenic retroposition of the lips sequel (IRLS) after bicuspid extraction, associated dentofacial characteristics and the effectiveness of surgical treatment. Material and methods: Patients with bicuspid extraction as part of an orthodontic treatment plan were retrospectively included. IRLS was i...

Introduction: The aim of this study was to examine the potential influence of antithrombotics on leukocyte- and platelet-rich fibrin (L-PRF) membranes. Methods: Tensile tests and cell counts were performed with L-PRF membranes originating from patients on anticoagulants and antiplatelets versus patients not taking antithrombotics. Results: For...

Aim The aim of the study was to assess the 5-year cumulative survival rate of implant-based dental rehabilitation following maxillofacial reconstruction with a vascularized bone flap and to investigate the potential risk factors which might influence the survival rate. Materials and methods A retrospective cohort study was designed. Inclusion crit...

Infection after maxillofacial trauma remains an important complication, with a significant socio-economic impact. While consensus exists that systemic antibiotic prophylaxis reduces the risk of infection in the management of maxillofacial fractures, the type, and duration remain controversial. Therefore, the purpose of this scoping review was to pr...

Objective This systematic review was performed to assess the potential influence of orthognathic surgery on root resorption (RR). Material and Methods An electronic search was conducted using PubMed, Web of Science, Cochrane Central and Embase for articles published up to April 2022. Following inclusion and exclusion criteria, a total of six artic...

Purpose To review the experience with orthognathic surgery in patients with systemic diseases, syndromic conditions or an oncological history at a tertiary center. Methods All patients who had undergone orthognathic surgery and all patients who were considered for orthognathic surgery between January 2013 and August 2020 at a tertiary center were...

Lack of evidence exists related to the three-dimensional (3D) pharyngeal airway space (PAS) changes at follow-up after isolated bilateral sagittal split osteotomy (BSSO) advancement surgery. The present study assessed the 3D PAS changes following isolated mandibular advancement at a follow-up period of 1 year. A total of 120 patients (40 males, 80...

Objective To investigate volumetric and circumferential pharyngeal airway space (PAS) changes and stability over time as evaluated with cone beam computed tomography (CBCT) before and after orthognathic surgery 2 years postoperatively.Materials and methodsOne hundred twenty-eight patients underwent bimaxillary orthognathic surgery at the Department...

Background Comorbidities influence treatment outcome of oral squamous cell carcinoma (OSCC). This study compared the predictive performance of six comorbidity scales for overall survival after surgery for OSCC. Methods We retrospectively analyzed OSCC patients, surgically treated at an academic center in Belgium between January 01, 2000 and Januar...