Periodontist Dr. Rokas Borusevičius: “I Was Often Motivated by the Fact That We Were Walking Terra Incognita”
Dr. Rokas Borusevičius
“Most of my days are devoted to caring for patients, helping to prevent or treat various dental, oral or gum diseases like periodontal and oral mucosa, restoring lost tissue, and carrying out dental implants. The rest of my time is dedicated to research work with the DIGITORR research team. Sometimes I give lectures at professional oral health training events, and from the spring semester, I hope to join the team of lecturers at the Institute of Dentistry of the Faculty of Medicine at Vilnius University,” said periodontist, Dr. Rokas Borusevičius. The researcher, who is interested in the historical heritage of Klaipėda-Memelis and Lithuania Minor, also collects pre-war artefacts related to medicine and this region. He is an enthusiast of authentic jazz music and culture, and dances – teaching others to dance in his free time. And this year, he has successfully defended his PhD dissertation in Dentistry at the Faculty of Medicine. We talked to Dr. R. Borusevičius about his dissertation research entitled, The Accuracy of Navigation Methods for Dental Implants and the Biocompatibility of Materials Used for Emergency Prostheses.
More accurate and safer dental implant techniques
Technological advances have had a major impact on dental science and clinical practice as we know it today: innovations such as scanners and volumetric computed tomography have allowed dentists to transfer a large part of a patient’s 3D anatomical data onto a computer. “This personalised copy of the face, teeth and jaws on a computer – a digital ‘version’ of the patient – has become an everyday tool for dentists during prosthodontic treatment,” explained Dr. R. Borusevičius. According to the doctor, the possibility to plan treatment and predict the final outcome on the computer is particularly important in the case of dental implants. “Today, it is common practice that when a patient loses a tooth, the prosthesis is placed on a dental implant: in the place of the lost tooth, an implant, made of a biocompatible material, is threaded into the jawbone, which functions as an artificial tooth root. This “root” is then topped with a crown – the visible part of the tooth that is needed for chewing.”
The doctor went on to describe how, all these components can be evaluated on the basis of computer data – to predict the location of the crown of the future tooth, to assess the adjacent anatomical structures that may be susceptible to damage (the nerve canal, the nasal floor, the floor of the paranasal sinus, the roots of the adjacent teeth, and so on), and to choose the exact position for the implant in the jaw. Then, the position of the implant as planned on the computer can be transferred to the patient’s mouth using various technologies. One of them is a 3D-printed template-aligner (a static surgical guide), which is positioned in the patient’s mouth during implant placement. “This template-aligner allows the dentist to guide the instruments precisely into the planned position. Another, newer technology is dynamic navigation, which tracks and transmits information about the position of the instruments in the jaw onto a computer screen in real time. It’s like road navigation on a smartphone. Research shows that these technologies significantly reduce human “free hand” error. In this way, these techniques provide a more precise and safer treatment for the patient,” said Dr. R. Borusevičius, who studied static and dynamic guided implantation techniques as part of his thesis.
Clinical simulations and collaboration with the Life Sciences Center
“I simulated different clinical situations based on human mandibular models, evaluated the impact of various related factors on the accuracy of the two technologies, and then compared them with each other. The dental implants were threaded into the models according to a digitally generated plan, then the resulting implant position was scanned and compared with the original plan on a computer, measuring five different types of errors. The study analysed a total of four different clinical situations (from a single missing tooth to a situation where all the teeth were lost), and compared not only the accuracy of the technology itself, but also the influence of implant position, different implant designs and the reference objects used”, said Dr. R. Borusevičius as he described the study. According to Dr. R. Borusevičius, the long-term success of such precise positioning of a dental implant in the jaw depends not only on the response of the bone tissue cells, which has been widely discussed in the scientific literature, but also on the response of the gum cells. “The gums form a protective barrier that envelops the implant crown that emerges from them. This protects the implant surface, the bone and other deeper tissues from bacteria or other harmful agents. The strength of the barrier is not only determined by the gums, but also by the properties of the surface of the implant component material, to which the gum cells adhere.”
Together with a team of biochemists from the Vilnius University Life Sciences Center, Dr. R. Borusevičius investigated the proliferation of primary cultures of human gingival fibroblasts on the surfaces of 11 different materials used in prosthetics. Of these, five were polymeric materials, including the innovative, less studied polymers (PEEK, PEKK) and 3D-printed polymers (PMMA). Five ceramic materials and titanium surfaces were also investigated. “The surfaces of these materials were polished in accordance with the manufacturers’ standard recommendations for prosthetic teeth and implants. The average surface roughness and hydrophilicity of each material was assessed. These were known from previous research, to be important surface characteristics related to cell response. The proliferation of human gingival fibroblasts was assessed by measuring their viability using MMT photocolorimetry after 24, 48 and 72 hours of incubation. The possibility of activating the surfaces of zirconia ceramic materials with ultraviolet radiation was also evaluated to facilitate cellular response,” explained the researcher. Overall, the thesis research involved the evaluation of digital technologies for the precise positioning of implants in bone and the most favourable prosthetic material for human gingival cells.
The main challenges? Poorly signposted paths
“Although digital technologies are developing very quickly, in the medical field they often take the form of “closed” commercial products. This is, of course, quite normal. However, for my thesis, I needed to find ways to integrate digital technologies, to compare them in a uniform protocol,” said Dr. R. Borusevičius. He explained how he had to “bump” into a number of dead ends before he was able to find the correct solutions. In the human gum cell part of the study, various methods had to be tested before it became clear which ones would go on to shape the results of the research and “make it into” the final dissertation. “I have often been motivated by the fact that we are walking terra incognita, exploring a topic in dentistry that is at the “cutting edge” of our focus and innovation. The desire to continue and move forward was especially strengthened when new publications, from colleagues abroad, on very similar research topics appeared in the PubMed database. I was also strongly motivated by the fact that I was working with the first ever dynamic navigation device (Navident) in Lithuania, which at that time was only available in a few dozen clinics in Europe,” said Dr. R. Borusevičius. The doctor is convinced that the success of any research depends to a large extent on the interdisciplinary, innovation and practical applicability of the results, the dissemination of the research and its results among fellow scientists and practitioners in Lithuania and abroad, as well as its dissemination and communication to the public who are not directly aware of the research.
Grateful for an inspiring environment
“I have been involved in the Student Scientific Society since the first year of my studies. I was lucky enough to get involved early in the research being developed at the Institute of Dentistry of Vilnius University’s Faculty of Medicine. Student research activities allowed me to meet Professor Vygandas Rutkūnas, thanks to whom I discovered my interest in dentistry. The topic of my dissertation research took shape and crystalised during both my undergraduate and residency studies. The topics of digital dentistry and innovative technologies, as well as the biological response of gingival cells, have always been of great interest to me and very applicable in practice,” said Dr. R. Borusevičius.
The doctor believes that every doctor is also a scientist: “When treating patients, it is essential to know the principles of science and evidence-based medicine and dentistry. You need to be able to read, understand, analyse and evaluate research. During my studies at the Institute of Dentistry, I have had no shortage of inspiring people who are not only excellent specialists in their field, but also scientists and lecturers. The most inspiring, were Prof. Vygandas Rutkūnas, Prof. Vytautė Pečiulienė, Prof. Vilma Brukienė, Dr. Arūnas Rimkevičius, Assoc. Prof. Rūta Rastenienė, Assoc. Prof. Saulius Drukteinis, Assoc. Prof. Linas Zaleckas, and Assoc. Prof. Ieva Gendvilienė. I think that the university’s Institute of Dentistry is really very rich with its bright and inspiring academic community. I am glad to have had the opportunity to grow and learn alongside great role models who have instilled in me the most important academic values.”
Dr. R. Borusevičius was also happy to have had the opportunity to work in an interdisciplinary environment – together with the team from the Biological Models Department at the Institute of Biochemistry of the Life Sciences Center of Vilnius University (Dr. Virginija Bukelskienė, Dr. Daiva Baltriukienė), the Anatomy, Histology and Anthropology Department at the Faculty of Medicine (Assoc. Prof. Arūnas Barkus), and the VU Centre for Laser Studies (Dr. Domas Paipulas). “The ability to understand the methods and research in related scientific fields has contributed significantly to my growth as a scientist and professional, and as a person,” concluded Dr. R. Borusevičius at the end of the interview.