Dental Hypotheses
Volume:12 Issue: 1, Jan-Mar 2021

Ten years ago a study reported on the lack of prerequisites in behavioral sciences and business management for entry into dental college. The primary objective of this follow-up study was to assess the current status of similar prerequisite courses in both U.S. and Canadian dental schools.

Required and recommended courses in behavioral sciences and in business in each North American dental school’s official online publication were analyzed in December 2019. Admissions requirements were readily available in sixty-five of the sixty-eight U.S. dental schools and in all ten schools in Canada; three U.S. schools were contacted by phone to collect the information.

Only nine (13.2%) U.S. and four (40%) Canada schools required at least one behavioral sciences course; however, thirty-nine (57.3%) U.S. and six (60%) Canada schools recommended a behavioral sciences course, most often in psychology, sociology, or communication. Zero (0%) of the total seventy-eight dental schools required a course in business; however, eighteen (26.5%) U.S. and two (20%) Canada schools recommended a business course, most often economics.

The authors strongly encourage the dental education community to again reconsider establishment of a minimum core of behavioral sciences and business courses as prerequisites in predoctoral dental education. Doing so will provide a much needed stronger foundation upon which to build upon in the curricula of dental schools.

The nature and progression of acute and chronic carious lesion are extremely variable on different tooth surfaces. Early detection of dental caries is challenging for clinicians and involves careful visual and tactile examination. Caries detection dyes and chemomechanical caries removal solutions guide the clinicians in the removal of infected dentin. This study aims to prepare and analyze the physical, chemical, and thermal characterizations of novel bioactive caries detecting dye solution (BCD) and its effectiveness in caries removal fromthetooth structure.Materials and

BCDis a combination of contrast agent (iobitridol), chitosan (CS), nanohydroxyapatite (nHAP), and coloring agent. It is synthesized, lyophilized, and subjected to Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimeter (DSC) analysis. Pilot study was conducted by applying BCD on two extracted carious teeth for evaluating caries removal efficiency under a microscope (10x). Scanning electron microscopy (SEM) image analysis was done to assess the percentage of dentinal tubules occlusion.

FTIR, XRD, and DSC analysis revealed that BCD has compatible interfacial bond between the components andis endothermic. Effective caries removal was seen under a microscope and SEM analysis revealed mean 77.66% of dentinal tubules occlusion.

BCD is a stable solution without exothermic reaction, has caries identifying potential, and helps in caries removal. BCD is also bioactive in nature due to the presence of CS and nHAP as ingredients.

Inflammasomes are multiprotein complexes, which regulate proinflammatory cytokines, Interleukin-18 (IL-18), and Interleukin-1b (IL-1b) that are associated with periodontal breakdown. This study investigated the expression of NOD-like receptor pyrin domain-containing-3 (NLRP3) and NOD-like receptor family CARD domain-containing protein 4 (NLRC4) inflammasomes in different periodontal diseases in humans and their potential association with IL-18 release in gingival crevicular fluid (GCF).

A total of 45 participants (21 males and 24 females) divided into four groups; periodontally healthy (H), gingivitis (G), chronic periodontitis (CP), and aggressive periodontitis (AgP) based on periodontal examination. NLRC4 and NLRP3 expression were detected by immunohistochemistry in gingival tissue samples for all groups. Expression percentage (%) and staining intensity distribution score (SID) were calculated for both NLRC4 and NLRP3. IL-18 was measured in GCF via enzyme linked immunosorbent assay (ELISA).

Positive immunoreactivity was seen for NLRC4 and NLRP3 across groups. No differences were found for NLRC4 expression %, but SID scores were slightly higher in G and AgP compared to other groups (P > 0.05). Results showed a significant increase of NRLP3 expression % in group CP compared to group H (P < 0.05) without affecting SID scores (P > 0.05). IL-18 levels were significantly higher in AgP and CP groups compared to H and G groups (P < 0.05). IL-18 significantly and positively correlated with clinical attachment levels across groups.

Within the limitations of this preliminary study, we suggest that the NLRC4 platform may have a protective role contrary to the NLRP3 platform influencing IL-18 release and associated periodontal tissue breakdown.

Fissure sealant therapy is a preventive method relied on covering pits and fissures to prohibit bacteria from settling on tooth and producing acid, which cause tooth demineralization. The benefits of caries prevention could only be achieved when the sealants remain intact for a long time, thus long-lasting retention is mandatory. Despite recently achieved improvement in sealant quality, their retention in long course remains a challenging issue in dentistry. The purpose of our study was to compare the clinical efficacy of sealants after using seventh generation adhesive and additional etchant material with fifth generation bonding agent.

In this randomized clinical trial, 40 patients in the age group of 7 to 12 years were randomly selected. All participants had a pair of sound first permanent molar in the mandible, which need fissure sealant therapy. For each patient, one tooth was treated with seventh generation bonding and separate etching material, and the counterpart tooth had undergone the fifth generation bonding system. A pediatric dentist did exert 6 and 12-mounth follow ups.

In 38 of 40 patients, who completed 6-month follow-up, the success rate of seventh generation adhesive was 84.2% and in the fifth generation group it was 76.3%. At 12-month follow-up, 36 patients were referred and success rate of fifth generation bonding was 52% and it was 36% in seventh generation adhesive. According to fisher test, the difference between two groups was not statistically significant.

This study depicted that fissure sealant retention was equal after 6 and 12 months in both methods.

Theories or hypotheses regarding the connection between COVID-19 and periodontal disease are increasing during the COVID-19 pandemic. COVID-19 has been reported to have adverse outcomes related to the establishment of a cytokine storm, which is similar to the cytokine expression profile and cells involved in periodontitis. Nevertheless, the exact etiology why cytokine storm is vulnerable in COVID-19 as well as periodontitis still not clearly understood.

Recently, the phenomenon of angry macrophages can be explained by M1/M2 macrophage polarization. Periodontitis patients that harbored Porphyromonas gingivalis have a greater M1/M2 ratio than healthy patients, thus have more active M1 macrophages that produce pro-inflammatory cytokines. We hypothesize that periodontal disease could be a burden in defense mechanism toward infectious diseases, particularly the COVID-19.

Endotoxin tolerance caused by P. gingivalis lipopolysaccharides shifts immune response from T helper (Th)-1 toward Th2, which leads to a less effective antivirus system. This mechanism may explain the connection between COVID-19 and periodontal disease through their cytokine profiles, microbial balance, and M1/M2 homeostasis. Recommendation for maintenance of oral hygiene and periodontal treatment is mandatory in the COVID era

SARS-CoV-2 is a novel coronavirus that causes an infectious disease named COVID-19. Respiratory distress syndrome and multiple organ failure are the common outcomes of COVID-19 that may finally lead to death. During COVID-19, cytokine storm takes place that is known by the release of notable amounts of pro-inflammatory cytokines including IL-1, IL-6, and TNF-a.

The Hypothesis:

 Periodontal disease are a group of inflammatory diseases in which elevated levels of some cytokine such as IL-1, IL-2, IL-5, IL-6, IL-10, and TNF-a are observed in patients’ serums. Due to the similarity of cytokine expressions in these two diseases, there might be a possible association between COVID-19 and periodontitis, especially the chronic type. Also, genotype polymorphisms of IL-1, IL-6, IL-10, and TNF-a have been proposed to be in association with chronic periodontitis susceptibility.

assessment of these polymorphisms may also play a significant role in detection of these diseases.

It is well known that the SARS-CoV-2 virus that causes COVID-19 could enter the human host through the oral cavity. In patients with periodontal disease, there is an increase of Furin, Cathepsin, and CD14+ CD16+ monocytes. The hypothesis stated here sheds light on the regular need of periodontal management to reduce inflammation and the levels of deleterious host enzymes and cytokines, which could pave the way for deadly viral diseases such as COVID-19.

The Hypothesis: 

Patients with periodontal disease are at increased risk of SARS-CoV-2 infection due to elevated levels of Furin and Cathepsin in oral cavity and COVID-19 complications like cytokine storm could occur with increased frequency in patients with periodontal disease due to the significant increase of CD14+ CD16+ monocytes in blood.

Evaluation of the Hypothesis:

 Oral and periodontal examination of patients with mild, moderate, and severe SARS-CoV-2 infection could shed light on the significant role played by periodontal disease in making an individual more prone to get SARS-CoV-2 infection by elevation of Furin and Cathepsin and the elevation of CD14+CD16+ monocytes and proinflammatory cytokines in the blood that could consequently worsen COVID-19 complications like cytokine storm. The blood counts of CD14+CD16+ monocytes need to be assayed in SARS-CoV-2 patients with and without periodontal disease to observe if periodontal disease as a coexisting condition elevates the proportion of CD14 CD16 + monocytes in SARS-CoV-2 patients. In fact, assessment of monocyte subsets in peripheral blood could be used as an immunosurveillance marker in SARS-CoV-2 patients. Hence, SARS-CoV-2 positive patients with chronic periodontal disease should be closely monitored for potential signs of a cytokine storm and its related complications.

The gold standard for pulpitis irreversible treatment is root canal treatment. However, it caused the loss of tooth vitality. To restore tooth vitality, materials that have regenerative ability in the pulp is needed. The exfoliated deciduous teeth stem cells (SHED) not only expressed specific markers for mesenchymal stem cells (MSC) but also induced the odontoblastic differentiation, and stimulating the formation of endothelium and fibroblast. The combination SHED with platelet rich fibrin (PRF) and chitosan were able to facilitate and increase the migration, proliferation and odontoblastic differentiation of dental pulp cells. Based on that fact, the combination of SHED, PRF and chitosan as three-dimensional tissue engineering is promising as new modality to pulp regeneration in the clinical setting. The purpose of this review is describing the potential combination of SHED, PRF, and chitosan scaffold as three-dimensional tissue engineering for pulp regeneration.

Regeneration can be done by stem cells derived from exfoliated deciduous teeth. Teeth that are formed from stem cells are denoted to as “tissue-engineered” teeth. In dentistry, mesenchymal stem cell-like populations were identified from both dental and nondental tissues has offered sensational opportunities for the application of tissue engineering as well as gene based therapies. These methods have the possibility to lead toward the growth of new approaches for regenerative periodontal therapy. Biodontics is the practice of dentistry that leads to the promotion of repair, restoration, and replacement of dental, oral, and craniofacial structures with natural biological materials of cellular source and it will substitute xenodontics, the practice of dentistry that uses external materials (e.g., metals and plastics) for this purpose.