The Nagai-Kim-Chen Lab is comprised of clinician-scientists focused on translational research that combines clinical and developmental research with basic science. This research covers clinical development, cognitive health and oral health, soft tissue and hard tissue regeneration, esthetic dentistry, the application of artificial intelligence in clinical dentistry, and other areas of study.
Our areas of interest and current projects:
Material Science and Clinical Development
Clinical Development of Simultaneous Non-Invasive Diagnosis and Therapeutic Treatment of Dental Caries
The goal of the proposed research is to develop a novel dental material (varnish) that both detects and inhibits dental caries. This will be achieved through an innovative combination of bisphosphonate and quantum dots (QDs) to concurrently enable non-invasive optical diagnostic imaging and arrest caries progression.
Oral Health and Cognitive Health
Paradigm Shift in the Molecular Transport to Brain through the Direct Central Nerve-Innervation Based Retrograde Axonal Transport of Craniofacial Tissue Exosomes (RATCE)
This study provides a data set supporting the hypothesis that craniofacial tissues (CFTs) express neurotrophic factors in exosomes for their retrograde axonal transport to brain via central nerves. Next generation sequencing (NGS) screened out multiple neurotrophic mRNAs that were overexpressed in cells of CFT origins compared to cranial nerve and glial cells. The corresponding protein expressions were confirmed in the exosomes. Furthermore, CFT-derived exosomes supported cell growth of cranial nerve cells. While cells, tissues, and organs communicate with paracrine and endocrine signaling, the brain has seemingly isolated from most peripheral molecules due to the blood brain barrier (BBB). The result of this study offers a paradigm shift and sheds light on the physiological transport by which the supply and demand of neurotrophic agents to the brain are balanced.
Integration of Oral and General Health - Association between Mastication and Cognitive Function by Case-Controlled, Population-Based, Matched-Cohort Study
According to the 2015 World Alzheimer Report, 147 million people live with dementia worldwide. This number is expected to increase to more than 131 million people by 2050. The goal of this study is to establish an effective preventive approach to integrating oral health and cognitive health to decrease oral risk factors for Alzheimer’s Disease.
Tissue Regeneration and Diagnosis
Dental Implant Surface Modification
The lab conducts both preclinical and clinical studies aimed at prevention and treatment of peri-implantitis. Specifically, the lab has developed a proprietary surface modification method to achieve “mucointegration” around dental implants. In preclinical and clinical studies, the lab is investigating methods to debride and “rejuvenate” implant surface in preparation for re-osseointegration.
Decoding Periodontal and Peri-Implantitis
Periodontitis, one of the leading causes of tooth loss, impacts the individual’s nutrition, function, and systemic health. In periodontitis, a dysbiosis of host mucosal tissues and microbiome on the tooth surface is thought to trigger an exaggerated inflammatory response in susceptible individuals. This dysregulation in the host immune response leads to the destruction of the periodontium which includes the tooth-supporting alveolar bone, gingiva, periodontal ligament, and cementum. Patients diagnosed with periodontal disease are also more prone to develop diseases around dental implants. Peri-implantitis is a pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant connective tissue and progressive loss of supporting bone. We are investigating the pathogenic mechanisms involved in periodontitis and peri-implantitis via high-phylogenetic-resolution microbiome mapping by fluorescence in situ hybridization (HiPR-FISH) and single cell RNA sequencing (scRNA-seq) in two ongoing cross-sectional studies.
Clinical Trials for Biomaterials for Soft and Hard Tissue Regeneration
Following tooth extractions, the alveolar ridge undergoes significant resorption which makes subsequent rehabilitation with dental implants a challenge. The lab conducts both preclinical animal studies as well as clinical trials to investigate the efficacy of various biomaterials.
Clinical Study
Color Vision in Dentistry
Color vision deficiency is a common disorder affecting vision that is seen in 8-12% of males and 0.5% of females. This study will determine whether dental professionals with color vision deficiency have different color matching capabilities than dental professionals without color vision deficiency. We hypothesized there was no difference in the ability to shade match between those with color vision deficiency and those with normal vision.
Efficacy of an Electric Toothbrush on the Glycemic Control for Type 2 Diabetes Patients With Chronic Periodontitis
Periodontitis is among the most prevalent chronic diseases in the world and it affects more than 50% of Americans. On the other hand, type 2 diabetes mellitus (T2DM) is a major public health concern, affecting 347 million adults worldwide. The relationship between periodontal diseases and diabetes has been well-established. Treatment of periodontal diseases improves diabetes outcomes. The aim of this study is to investigate the efficacy of an electric toothbrush with a custom app on glycemic control in Type 2 diabetic patients with chronic periodontitis.
Artificial Intelligence-Based Interagency
Development of Innovative Artificial Intelligence-Based Algorithm for an Accurate Tooth Prognosis Decision
Appropriate comprehensive treatment planning with a multidisciplinary approach is essential in clinical dentistry. It requires the evaluation of all oral health conditions, including the occlusal scheme, arch forms, and more. The aim of this study is to develop an efficient and accurate tooth prognosis decision tool using an AI-based-algorithm, which leads to appropriate comprehensive treatment planning.
