Shan Gao has served at Journal of Oral Pathology and Medicine (JOPM) for 20 years, and currently as Associate Editor of JOMP, Beijing, China. After he finished his 8 year education in Stomatology for both bachelor and master degrees, he started 10 years of clinic practice in Endodontics and Oral Medicine in China, followed by 12 years basic research work in Molecular Biology, including 3 years for a PhD degree in Denmark and 10 years industry experience in a leading RNAi therapeutic company in China. During those years of experience, he built up a close relationship with Oral Pathology and Oral Medicine. It is great opportunity to introduce his story together with JOPM, accompanying with his personal research experience, at the moment of the 50th Anniversary of JOPM.

The oral cavity is a complex ecosystem accommodating various microorganisms (e.g., bacteria and fungi). Various factors, such as diet change and poor oral hygiene, can change the composition of oral microbiota, resulting in the dysbiosis of the oral micro-environment and the emergence of pathogenic microorganisms, and consequently, oral infectious diseases. Systemic administration is frequently used for drug delivery in the treatment of diseases and is associated with the problems, such as drug resistance and dysbiosis. To overcome these challenges, oral drug delivery systems (DDS) have received considerable attention. In this literature review, the related articles are identified, and their findings, in terms of current therapeutic challenges and the applications of DDSs, especially nanoscopic DDSs, for the treatment of oral infectious diseases are highlighted. DDSs are also discussed in terms of structures and therapeutic agents (e.g., antibiotics, antifungals, antiviral, and ions) that they deliver. In addition, strategies (e.g., theranostics, hydrogel, microparticle, strips/fibers, and pH-sensitive nanoparticles), which can improve the treatment outcome of these diseases, are highlighted.

Oral squamous cell carcinoma (OSCC) is prevalent around the world and is associated with poor prognosis. OSCC is typically diagnosed from tissue biopsy sections by pathologists who rely on their empirical experience. Deep learning models may improve the accuracy and speed of image classification, thus reducing human error and workload. Here we developed a custom-made deep learning model to assist pathologists in detecting OSCC from histopathology images. We collected and analyzed a total of 2,025 images, among which 1,925 images were included in the training set and 100 images were included in the testing set. Our model was able to automatically evaluate these images and arrive at a diagnosis with a sensitivity of 0.98, specificity of 0.92, positive predictive value of 0.924, negative predictive value of 0.978, and F1 score of 0.951. Using a subset of 100 images, we examined whether our model could improve the diagnostic performance of junior and senior pathologists. We found that junior pathologists were able to delineate OSCC in these images 6.26 min faster when assisted by the model than when working alone. When the clinicians were assisted by the model, their average F1 score improved from 0.9221 to 0.9566 in the case of junior pathologists and from 0.9361 to 0.9463 in the case of senior pathologists. Our findings indicate that deep learning can improve the accuracy and speed of OSCC diagnosis from histopathology images.

OBJECTIVE: The presentation-assimilation-discussion (PAD) class is a novel teaching method in which half the class time is allocated for the instructor\'s presentation and the other half for student\'s assimilation and discussion. This study evaluates and compares the teaching outcomes of the PAD class and traditional lecture-based method in oral pathology courses in School of Stomatology, Kunming Medical University.
METHODS: The experimental and control groups included 88 undergraduates from Class 2017 and 72 undergraduates from Class 2016, respectively. The PAD method was applied on the experimental group in 2019, whereas the traditional lecture-based method was applied on the control group in 2018. The two groups\' teaching outcomes were compared using final theory tests, biopsy diagnostic tests, and questionnaires. The Mann-Whitney U-test and independent-sample t-test were adopted for statistical analysis.
RESULTS: In five multiple-choice questions examining the same knowledge point from final theory tests, the distribution of the final scores showed a statistically significant difference between the two groups (p < 0.05). In the biopsy diagnostic tests, the experimental group scored higher than the control group (p < 0.05). In the questionnaires, there was no statistically significant difference for the \"enhancing knowledge mastery\" item (p > 0.05). However, the experimental group showed significant superiority in the remaining nine items (p < 0.05). [Correction added on August 30, 2021, after first online publication: The data value p was corrected in the last sentence of result section.] CONCLUSIONS: Compared with the traditional lecture-based teaching, the PAD class stimulated a passion for learning among students and results in improved teaching outcomes. Therefore, the application of PAD class in oral pathology teaching should be recommended.

Implant dentistry has become a popular restorative option in clinical practice. Titanium and titanium alloys (TTA) are the gold standard for endo-osseus dental implants production, thanks to their biocompatibility, resistance to corrosion and mechanical properties. The characteristics of the TTA implant surface seem to be particularly relevant in the early phase of osseointegration. Furthermore, the microstructure of implant surface can largely influence the bone remodelling at the level of the bone-implant surface. Recently, research has stated on the long-term of both survival and success rates of osseointegrated implants and mainly on biomechanical aspects, such as load distribution and biochemical and histological processes at the bone-implant interface. This short review reports recent knowledge on chemical and mechanical properties, biological aspects, innovations in preventing peri-implantitis, describing clinical applications and recent improvements of TTA dental implants. In addition, it highlights current knowledge about a new implant coating that has been demonstrated to reduce the number of initially adhering bacteria and peri-implantitis.

Gingivitis and periodontitis (GP) are the main diseases of the oral cavity. The ethiology of GP have never been completely understood, however, loss of balance between the host immune system and the microbial virulence of GP pathogens may be considered the trigger of GP. In fact, the immune system, activated by microbiological agents, attacks the host and not the biofilm bacteria, causing the destruction of periodontal tissue, alveolar bone, and loss of teeth. Parasites may play an important role in the pathology of GP. The first studied and the most common parasite in the oral cavity is Entamoeba gingivalis. A possible link between E. gingivalis and GP has never been demonstrated completely, however E. gingivalis is infrequently found in people without GP. In addition, there is evidence that E. gingivalis could favour the onset and progression of GP. In conclusion, we can assert that E. gingivalis and GP may be correlated. This relationship can open new therapeutical approaches for treating GP, particularly in cases refractory to therapy.

Reconstructive surgery (RS) is necessary before implant placement to regenerate bone defects. Success rate of implants is related to RS and to the correct position of implants in residual crest. The most popular surgical procedures of RS are bone grafts, guided bone regeneration. Bone graft is the gold standard technique to achieve RS of edentulous crests. RS is a surgical technique that uses barrier membranes to promote osteoblast cells proliferation. RS is often combined with bone grafting procedures. Sinus floor elevation procedures are elective treatments when there is insufficient bone height for implant insertion in maxilla. Bone osteogenesis distraction is the process of RS between two bone segments in response to tensile stress. The aim of this short review is to analyze the different methods of RS: bone grafts, guided bone regeneration, maxillary sinus floor elevation, and bone osteogenesis distraction.

Implant dentistry has emerged as a first line of treatment to replace missing teeth for both the edentulous and partially dentate patients. Implant dentistry is accompanied by the onset of peri-implantitis (PIM). PIM is characterized by the inflammatory destruction of the implant-supporting tissues, because of biofilm formation on the implant surface. A history of periodontitis, poor oral hygiene, and smoking are considered as risk factors for PIM. Occasionally PIM is associated with iatrogenic factors, that, only recently, have been acknowledged as direct cause of PIM, i.e.: non-parallel adjacent implants or the presence of a gap, between fixture and prosthetic components. The use both of traditional protocols of nonsurgical periodontal therapy and the laser seems to be an effective alternative treatment modality for PMI. By the application of laser-assisted non-surgical peri-implant therapy the periodontal pocket depth was reduced. The present article illustrates the nonsurgical management of one case, where failure to remove residual cement, from an implant-supported dental prosthesis, seemed to cause PMI.

Periodontal diseases (PDs) affect about half of the adult population all over the world. PDs are caused by bacterial infection which induces an inflammatory response with progressive destruction of the periodontal tissues and finally the loss of teeth. Tobacco smoking (TS), alcohol consumption, and systemic diseases (SDs), are considered additional risk factors. This short review examines the potential causal association between PDs, TS and SDs. There is strong evidence that PDs are associated with an increased risk of SDs. In addition, many patients with SDs are also affected by PD, which can be mild or severe, and tobacco smokers manifest a greater risk of developing PDs. This paper includes many randomized controlled trials and reviews to test the effects of different periodontal therapies for patients with SDs.

Odontogenic abscesses are one of the most common dental diseases causing maxillofacial skeletal lesions. They affect the individual\'s ability to maintain the dental structures necessary to obtain adequate nutrition for survival and reproduction. In this study, the prevalence and pattern of odontogenic abscesses in relation to age, sex, matriline, and living periods were investigated in adult rhesus macaque skeletons of the free-ranging colony on Cayo Santiago, Puerto Rico.
The skulls used for this study were from the skeletons of 752 adult rhesus macaques, aged 8-31 years, and born between 1951 and 2000. They came from 66 matrilines ranging from 1 to 88 individuals. Fistulae or skeletal lesions caused by odontogenic abscesses drainage, carious lesions, tooth fractures, tooth loss, and alveolar resorption were evaluated visually.
Seventy-two specimens (9.57%) had odontogenic abscesses of varying severity. Males had a significantly higher prevalence than females. The prevalence of odontogenic abscesses in several matrilines was significantly higher than in the population as a whole. Animals born between 1950 and 1965 tended to have a higher prevalence of odontogenic abscesses than those born in later periods.
These results suggest that oral pathologies, such as dental and periodontal abscesses in rhesus macaques are fairly common, which may indicate familial effects interwoven with ecological and social factors. The closeness of the rhesus and human genomes allows insights to understand of the epidemiology of these diseases in the human population. Further assessment of the role played by environmental and familial factors on rhesus oral health and disease are warranted.