Background Cemento-osseous dysplasia is a benign fibro-osseous lesion of the tooth-bearing region of the jaws with a periodontal ligament origin. It appears predominantly in Black and Asian middle-aged females. Its importance is that it could mimic a periapical lesion in the early, translucent stage. Case presentation In this report a rare case of familial cemento-osseous dysplasia is presented: a 50-years old Caucasian woman with labial paraesthesia and radiological translucency around the roots of the mandibular incisors and the first molar teeth. The lesion around the first molar was diagnosed as periapical granuloma and a root canal treatment was carried out. The diagnosis of florid cemento-osseous dysplasia and the treatment plan based on two- and three-dimensional radiographic examinations were certified histologically after surgical removal of the lesion. We screened the family members - including the patient’s mother, daughter and son - and identified a periapical version of cemento-osseous dysplasia in the daughter. Our case highlights the difficulties of differential diagnosis of cemento-osseous dysplasia and other periapical pathologies. The inconsistencies in the present classification of cemento-osseous dysplasia are also discussed with a proposal for a different classification based on new aspects that would be very helpful in setting up a correct treatment plan. Conclusion Differentiation of endodontic and non-endodontic origin of radiolucency and distinguishing it from anatomical landmarks by appropriate clinical evaluation and using vitality testing can give an opportunity to prevent unnecessary endodontic treatment. The current categories of cemento-osseous dysplasia classification do not cover the early stage of a hereditary florid form of cemento-osseous dysplasia. Instead of anatomical location of the lesion, clinical and genetic features may be recommended as parameters of cemento-osseous dysplasia classification.

The main driver of osteoporosis is an imbalance between bone resorption and formation. The pathogenesis of osteoporosis has also been connected to genetic alterations in key osteogenic factors and dysfunction of bone marrow mesenchymal stem/stromal cells (BM-MSCs). Tks4 (encoded by the Sh3pxd2b gene) is a scaffold protein involved in podosome organization. Homozygous mutational inactivation of Sh3pxd2b causes Frank-ter Haar syndrome (FTHS), a genetic disease that affects bone tissue as well as eye, ear, and heart functions. To date, the role of Tks4 in adult bone homeostasis has not been investigated. Therefore, the aim of this study was to analyze the facial and femoral bone phenotypes of Sh3pxd2b knock-out (KO) mice using micro-CT methods. In addition to the analysis of the Sh3pxd2b -KO mice, the bone microstructure of an FTHS patient was also examined. Macro-examination of skulls from Tks4-deficient mice revealed craniofacial malformations that were very similar to symptoms of the FTHS patient. The femurs of the Sh3pxd2b -KO mice had alterations in the trabecular system and showed signs of osteoporosis, and, similarly, the FTHS patient also showed increased trabecular separation/porosity. The expression levels of the Runx2 and osteocalcin bone formation markers were reduced in the bone and bone marrow of the Sh3pxd2b -KO femurs, respectively. Our recent study demonstrated that Sh3pxd2b -KO BM-MSCs have a reduced ability to differentiate into osteoblast lineage cells; therefore, we concluded that the Tks4 scaffold protein is important for osteoblast formation, and that it likely plays a role in bone cell homeostasis.

Medication-Related Osteonecrosis of the Jaws (MRONJ) is a difficult-to-treat complication of the therapy of osteoporosis and some malignancies cured with bisphosphonates and antiresorptive drugs. The pathomechanism is unclear, but there is increasing observation that Actinomyces infection may play a role in its development and progression. The aim of our study was to demonstrate that histological examination using a validated triple staining procedure for Actinomyces bacteria strains can detect a high rate of Actinomyces infection in patient's samples with MRONJ. 112 previously hematoxylin-eosin (HE) stained samples submitted with the clinical diagnosis of MRONJ were re-evaluated histologically using an appropriate triple special staining validated for the identification of Actinomyces infection. During the first evaluation, when pathologists did not specifically look for Actinomyces, only 8.93% of the samples were reported as positive. In contrast, re-evaluation with triple staining provided a yield of 93.7% positive samples, therefore, we suggest the triple special staining to be standard in MRONJ histology evaluation. These results show that if the clinician suspects Actinomyces infection and brings this to the attention of the pathologist, it could significantly increase the number of correct diagnoses. It serves as an aid for clinicians in therapeutic success of MRONJ by selecting a long-term adequate antibiotic medication which is suitable for the elimination of actinomyces infection.

Billions of microorganisms can be found in the oral cavity, from which bacteria are the most frequent. More than 600 bacterial species can be isolated. Most of them are harmless, moreover, some species prove themselves to be specifically useful. However, in the case of a weakened immune status or inappropriate oral hygiene, they may cause many types of soft and hard tissue disorders. Caries and periodontal diseases are the most common bacterial diseases of the oral cavity. In both cases, the dental biofilm gives rise to the disorder, which is caused by the insufficient oral hygiene. Dental caries are mainly caused by cariogenic streptococci and lactobacilli. In the case of serious periodontal diseases, anaerob parodonto-pathogen microorganisms play the major role. Untreated caries may result in the necrosis of the pulp, which can cause an inflammation expanding towards the parodontium. This can be characterized as a focal infection, like the untreated periodontal pockets. Dental foci may have lots of systemic consequences such as cardiovascular diseases, diabetes, pneumonia, arthritis, preterm birth and alopecia areata. When these diseases occur, dental foci should always be considered. The professional plaque control and chlorhexidine rinsing before the proposed surgeries have an outstanding role in the prevention of ventilator-associated pneumonia. Oral cancer is multicausal; more and more researchers are analyzing the role of certain bacteria in the carcinogenesis of oral cancer. In addition to the mentioned clinical aspects, we are planning to describe the relatively rare, but diverse and diagnostically challenging bacterial soft tissue disorders in another publication. Orv Hetil. 2019; 160(19): 739–746.

High-grade B-cell lymphoma not otherwise specified is listed as a new group in the WHO 2017 statement as a subtype of aggressive, mature B-cell lymphomas with a poor prognosis. To our knowledge, no description of this genetic type of maxillary lymphoma has appeared in the literature until now; thus, our case provides valuable data on its symptoms, clinical behavior, response to treatment and survival rate. The present report describes the early diagnosis and treatment of an extremely rare histological subtype of B-cell lymphoma, a case of high-grade B-cell lymphoma not otherwise specified, localized in the maxillary sinus and mimicking signs and symptoms of periapical inflammation. After chemotherapy, the presented patient showed complete remission without relapse and systemic spread. As far as we know, this is the first reported case of this rare type of lymphoma associated with the maxillary sinus. Considering that high-grade B-cell lymphomas are aggressive tumors with rapid growth and poor prognosis, which are often misdiagnosed in the early stages as inflammatory disease, it is relevant to highlight the importance of a detailed evaluation of clinical signs and radiological findings during diagnosis, especially if they contradict each other.