Interdisciplinary management of Type 3 oligodontia: A retrospective case series.

STATEMENT OF PROBLEM: Type 3 oligodontia is the most dentoalveolar deficient manifestation of congenital tooth absence. There is a need to rehabilitate these children functionally and esthetically to improve quality of life. PURPOSE: The purpose of this retrospective case series was to evaluate the short- and intermediate-term outcomes of the dental treatment provided in a children's hospital and to develop a sequential interdisciplinary treatment planning protocol from infancy to the completion of jaw development. MATERIAL AND METHODS: A total of 10 patients were included in this retrospective longitudinal case series report. Different interventions had been carried out at times related to growth and development of the jaws. Implant-supported fixed dental prostheses were provided after the lateral growth of the anterior mandible had stabilized at around 12 years of age. Definitive mandibular prostheses were provided after the cessation of growth and following maxillary treatment. Treatment for the maxilla was more complex. Bone grafted and graftless implant-supported fixed prostheses were offered as alternatives to a complete denture. Implant stability and soft tissue response were evaluated at prosthesis removal. RESULTS: Seven patients received a 4-implant and 2 a 5-implant-supported immediately loaded fixed mandibular prosthesis. One patient elected to maintain the interim complete denture. Of the 38 implants, 2 failed and were satisfactorily replaced. In the maxilla, 4 patients elected to maintain a complete denture, and 6 received a maxillary implant-supported fixed prosthesis: 1 with bilateral sinus lift bone grafting and 6 regular implants; 1 with 6 regular implants; 1 with 4 regular implants; 2 with bilateral zygoma implants plus 2 regular anterior implants; and 1 with 4 zygoma implants. No implant failures were recorded in the maxilla. Follow-up for mandibular treatment ranged from 1 to 12 years and for maxillary treatment 1 to 9 years. All implants were classified as asymptomatic and surviving. CONCLUSIONS: The use of fixed implant-supported prostheses in selected individuals with Type 3 oligodontia can improve functional and esthetic outcomes as compared with the use of removable prostheses alone. Implant-supported prostheses require an interdisciplinary approach from early childhood until growth cessation.

Giardia intestinalis reshapes mucosal immunity toward a Type 2 response that attenuates inflammatory bowel-like diseases.

Diarrheal diseases are the second leading cause of death in children worldwide. Epidemiological studies show that co-infection with Giardia intestinalis decreases the severity of diarrhea. Here, we show that Giardia is highly prevalent in the stools of asymptomatic school-aged children. It orchestrates a Th2 mucosal immune response, characterized by increased antigen-specific Th2 cells, IL-25, Type 2-associated cytokines, and goblet cell hyperplasia. Giardia infection expanded IL-10-producing Th2 and GATA3+ Treg cells that promoted chronic carriage, parasite transmission, and conferred protection against Toxoplasma gondii-induced lethal ileitis and DSS-driven colitis by downregulating proinflammatory cytokines, decreasing Th1/Th17 cell frequency, and preventing collateral tissue damage. Protection was dependent on STAT6 signaling, as Giardia-infected STAT6-/- mice no longer regulated intestinal bystander inflammation. Our findings demonstrate that Giardia infection reshapes mucosal immunity toward a Type 2 response, which confers a mutualistic protection against inflammatory disease processes and identifies a critical role for protists in regulating mucosal defenses.

Optimization of electroporation method and promoter evaluation for type-1 methanotroph, Methylotuvimicrobium alcaliphilum.

Methanotrophic bacteria are promising hosts for methane bioconversion to biochemicals or bioproducts. However, due to limitations associated with long genetic manipulation timelines and, lack of choice in genetic tools required for strain engineering, methanotrophs are currently not employed for bioconversion technologies. In this study, a rapid and reproducible electroporation protocol is developed for type 1 methanotroph, Methylotuvimicrobium alcaliphilum using common laboratory solutions, analyzing optimal electroshock voltages and post-shock cell recovery time. Successful reproducibility of the developed method was achieved when different replicative plasmids were assessed on lab adapted vs. wild-type M. alcaliphilum strains (DASS vs. DSM19304). Overall, a ∼ 3-fold decrease in time is reported with use of electroporation protocol developed here, compared to conjugation, which is the traditionally employed approach. Additionally, an inducible (3-methyl benzoate) and a constitutive (sucrose phosphate synthase) promoter is characterized for their strength in driving gene expression.

Perspective on Lignin Conversion Strategies That Enable Next Generation Biorefineries.

The valorization of lignin, a currently underutilized component of lignocellulosic biomass, has attracted attention to promote a stable and circular bioeconomy. Successful approaches including thermochemical, biological, and catalytic lignin depolymerization have been demonstrated, enabling opportunities for lignino-refineries and lignocellulosic biorefineries. Although significant progress in lignin valorization has been made, this review describes unexplored opportunities in chemical and biological routes for lignin depolymerization and thereby contributes to economically and environmentally sustainable lignin-utilizing biorefineries. This review also highlights the integration of chemical and biological lignin depolymerization and identifies research gaps while also recommending future directions for scaling processes to establish a lignino-chemical industry.

Dentition and weight status in community-dwelling older adults.

BACKGROUND/OBJECTIVE: Tooth loss is common among older adults and can affect dietary intake and weight status. This study investigated associations between dentition status and body mass index (BMI) in older adults. MATERIALS AND METHODS: This was a cross-sectional study of data from a convenience sample of older adults (65-89 years) treated at an urban U.S. dental school clinic. Clinical and demographic data were obtained from electronic health records. Dentition status was determined based on data from odontograms. Multinomial logistic regression was used to estimate the odds ratio (OR) and 95% confidence interval (CI) of having a non-normal weight status for each measure of dentition status, after adjusting for covariates. RESULTS: Patients (n = 1765) were 54.1% female, 51.5% White, 41.6% African American and 22.5% Hispanic/Latino. The median (interquartile range [IQR]) age was 71 (67.0-75.0) years; the mean (±SD) BMI was 28.5 (±5.7) kg/m2 ; 72.5% were overweight or obese. The median (IQR) number of remaining teeth was 20.0 (13.0-24.0); the median numbers of anterior and posterior occluding pairs of teeth were 5.0 (2.0-6.0) and 2.0 (0.0-5.0), respectively; and 44.9% had a functional dentition (≥21 teeth). Having a higher number of remaining teeth and more posterior occluding pairs were associated with lower odds of obesity (OR = 0.980, 95% CI = 0.964, 0.997, p = .022 and OR = 0.931, 95% CI = 0.885, 0.980, p = .006, respectively). Lack of a functional dentition was associated with higher odds of obesity (OR = 1.400, 95% CI = 1.078, 1.818, p = .012), after controlling for covariates. CONCLUSION: Older adults with tooth loss - especially loss of posterior occlusion and lack of a functional dentition - were more likely to be obese than of normal weight.

An Engineered Laccase from Fomitiporia mediterranea Accelerates Lignocellulose Degradation.

Laccases from white-rot fungi catalyze lignin depolymerization, a critical first step to upgrading lignin to valuable biodiesel fuels and chemicals. In this study, a wildtype laccase from the basidiomycete Fomitiporia mediterranea (Fom_lac) and a variant engineered to have a carbohydrate-binding module (Fom_CBM) were studied for their ability to catalyze cleavage of ß-O-4' ether and C-C bonds in phenolic and non-phenolic lignin dimers using a nanostructure-initiator mass spectrometry-based assay. Fom_lac and Fom_CBM catalyze ß-O-4' ether and C-C bond breaking, with higher activity under acidic conditions (pH < 6). The potential of Fom_lac and Fom_CBM to enhance saccharification yields from untreated and ionic liquid pretreated pine was also investigated. Adding Fom_CBM to mixtures of cellulases and hemicellulases improved sugar yields by 140% on untreated pine and 32% on cholinium lysinate pretreated pine when compared to the inclusion of Fom_lac to the same mixtures. Adding either Fom_lac or Fom_CBM to mixtures of cellulases and hemicellulases effectively accelerates enzymatic hydrolysis, demonstrating its potential applications for lignocellulose valorization. We postulate that additional increases in sugar yields for the Fom_CBM enzyme mixtures were due to Fom_CBM being brought more proximal to lignin through binding to either cellulose or lignin itself.

Psychosocial and behavioural impact of three clinical presentations of oligodontia in a tertiary hospital.

PURPOSE: To investigate the psychosocial and behavioural impact of oligodontia across three presentation types and determine if presentation type can infer impact. MATERIALS/METHODS: Thirty patients, diagnosed and treated for oligodontia between 2006 and 2021, identified from hospital records. Patients received two questionnaires; the first was a modified version of a condition-specific questionnaire, the Cleft Research Questionnaire (CRQ),used to investigate demographic, life and treatment details and impacts, and the second, the Oral Health Impact Profile (OHIP-14) used to investigate the oral health related quality of life. Patients were assigned to three presentations (Types 1 to 3) of oligodontia identified according to the edentulous space present and complexity of prosthodontic treatment required. Hypothesis test to determine if there is a relationship between oligodontia type and study variables. RESULTS: Twenty-two questionnaires were completed and returned. There were 9 females. The age range was from 16 to 32 years. Eighteen patients had nonsyndromic and 4 oligodontia associated with anhidrotic ectodermal dysplasia. The main areas of impact were patient reported life less satisfying (64.5%, n=14)(pre-treatment), making friends (45%, N=10), school participation (45%, n=10), and public speaking (45%, n=10). No relationship was discovered between the degree of physical effect of the presentation type and study variables including the degree of psychosocial impact or life satisfaction. CONCLUSION: Oligodontia can have a negative functional and social impact on a patient prior to prosthodontic treatment. Prosthodontic treatment improved the life satisfaction for most patients. Psychosocial outcomes could not be inferred by the presentation type of oligodontia.

A Diabetic Patient with Acute Osteomyelitis Presenting with Jaw Pain and Submandibular Swelling.

This case scenario shows the value of applying relevant imaging and the selection of appropriate antibiotic via culture and sensitivity before prescribing especially when dealing with a patient with type 1 Diabetes Mellitus. When confronted with a diagnosis of acute osteomyelitis, it is always better to refer the patient to a hospital for admission where the management and any other intervention is easily accomplished. Admission to the hospital, culture and sensitivity, and appropriate intravenous antibiotics may have limited the progress of the infection and ultimately may have prevented the sequestration in this patient, limiting the degree of morbidity. Monitoring and control of blood glucose levels is an important part of the management in a patient from this scenario.

A Pregnant Patient (First Trimester) Reporting for Pain in Relation to the Maxillary Left First Molar Was Prescribed a Full Mouth Series Radiographs in the Dental Office.

This case scenario shows the value of conducting a thorough clinical examination that will direct appropriate radiographic selection and prescription criteria to be able to arrive at a diagnosis. Proper management of a patient's chief complaint and imaging needs during pregnancy is of utmost importance. It is prudent to limit ionizing radiation during the first trimester to what is minimally needed and defer elective imaging until after the birth of the baby. It is important for dental health care providers to do what is necessary for the patient for the emergent situation and postpone all elective imaging and follow the published FDA/ADA radiographic selection criteria.

Simultaneous carbon catabolite repression governs sugar and aromatic co-utilization in Pseudomonas putida M2.

Pseudomonas putida have emerged as promising biocatalysts for the conversion of sugars and aromatic compounds obtained from lignocellulosic biomass. Understanding the role of carbon catabolite repression (CCR) in these strains is critical to optimize biomass conversion to fuels and chemicals. The CCR functioning in P. putida M2, a strain capable of consuming both hexose and pentose sugars as well as aromatic compounds, was investigated by cultivation experiments, proteomics, and CRISPRi-based gene repression. Strain M2 co-utilized sugars and aromatic compounds simultaneously; however, during cultivation with glucose and aromatic compounds (p-coumarate and ferulate) mixture, intermediates (4-hydroxybenzoate and vanillate) accumulated, and substrate consumption was incomplete. In contrast, xylose-aromatic consumption resulted in transient intermediate accumulation and complete aromatic consumption, while xylose was incompletely consumed. Proteomics analysis revealed that glucose exerted stronger repression than xylose on the aromatic catabolic proteins. Key glucose (Eda) and xylose (XylX) catabolic proteins were also identified at lower abundance during cultivation with aromatic compounds implying simultaneous catabolite repression by sugars and aromatic compounds. Reduction of crc expression via CRISPRi led to faster growth and glucose and p-coumarate uptake in the CRISPRi strains compared to the control, while no difference was observed on xylose+p-coumarate. The increased abundances of Eda and amino acid biosynthesis proteins in the CRISPRi strain further supported these observations. Lastly, small RNAs (sRNAs) sequencing results showed that CrcY and CrcZ homologues levels in M2, previously identified in P. putida strains, were lower under strong CCR (glucose+p-coumarate) condition compared to when repression was absent (p-coumarate or glucose only).IMPORTANCEA newly isolated Pseudomonas putida strain, P. putida M2, can utilize both hexose and pentose sugars as well as aromatic compounds making it a promising host for the valorization of lignocellulosic biomass. Pseudomonads have developed a regulatory strategy, carbon catabolite repression, to control the assimilation of carbon sources in the environment. Carbon catabolite repression may impede the simultaneous and complete metabolism of sugars and aromatic compounds present in lignocellulosic biomass and hinder the development of an efficient industrial biocatalyst. This study provides insight into the cellular physiology and proteome during mixed-substrate utilization in P. putida M2. The phenotypic and proteomics results demonstrated simultaneous catabolite repression in the sugar-aromatic mixtures, while the CRISPRi and sRNA sequencing demonstrated the potential role of the crc gene and small RNAs in carbon catabolite repression.

A shotgun metagenomic analysis of the fecal microbiome in humans infected with Giardia duodenalis.

BACKGROUND: The mechanisms underlying the clinical outcome disparity during human infection with Giardia duodenalis are still unclear. In recent years, evidence has pointed to the roles of host factors as well as parasite's genetic heterogeneity as major contributing factors in the development of symptomatic human giardiasis. However, it remains contested as to how only a small fraction of individuals infected with G. duodenalis develop clinical gastrointestinal manifestations, whereas the majority of infected individuals remain asymptomatic. Here, we demonstrate that diversity in the fecal microbiome correlates with the clinical outcome of human giardiasis. METHODS: The genetic heterogeneity of G. duodenalis clinical isolates from human subjects with asymptomatic and symptomatic giardiasis was determined using a multilocus analysis approach. We also assessed the genetic proximity of G. duodenalis isolates by constructing phylogenetic trees using the maximum likelihood. Total genomic DNA (gDNA) from fecal specimens was utilized to construct DNA libraries, followed by performing paired-end sequencing using the HiSeq X platform. The Kraken2-generated, filtered FASTQ files were assigned to microbial metabolic pathways and functions using HUMAnN 3.04 and the UniRef90 diamond annotated full reference database (version 201901b). Results from HUMAnN for each sample were evaluated for differences among the biological groups using the Kruskal-Wallis non-parametric test with a post hoc Dunn test. RESULTS: We found that a total of 8/11 (72.73%) human subjects were infected with assemblage A (sub-assemblage AII) of G. duodenalis, whereas 3/11 (27.27%) human subjects in the current study were infected with assemblage B of the parasite. We also found that the parasite's genetic diversity was not associated with the clinical outcome of the infection. Further phylogenetic analysis based on the tpi and gdh loci indicated that those clinical isolates belonging to assemblage A of G. duodenalis subjects clustered compactly together in a monophyletic clade despite being isolated from human subjects with asymptomatic and symptomatic human giardiasis. Using a metagenomic shotgun sequencing approach, we observed that infected individuals with asymptomatic and symptomatic giardiasis represented distinctive microbial diversity profiles, and that both were distinguishable from the profiles of healthy volunteers. CONCLUSIONS: These findings identify a potential association between host microbiome disparity with the development of clinical disease during human giardiasis, and may provide insights into the mechanisms by which the parasite induces pathological changes in the gut. These observations may also lead to the development of novel selective therapeutic targets for preventing human enteric microbial infections.

A user-centered approach to the development of a diet education tool for older adults with tooth loss.

BACKGROUND: Tooth loss is associated with suboptimal nutrient intake and greater risk of malnutrition. OBJECTIVE: To develop and field-test a stakeholder-informed diet education tool that addresses the unique needs of older adults with tooth loss who do not wear dentures. METHODS: An iterative user-centered approach was used. Initial content was developed based on findings from previous research. Stakeholder panels of older adults with 20 or fewer teeth, and dentists, were conducted at two time points to obtain feedback on the tool, which was revised following each panel. The tool was field-tested in a dental school clinic and evaluated using the Patient Education Materials Assessment Tool; it was further revised based on feedback. RESULTS: A diet education tool entitled "Eating Healthier With Tooth Loss" was developed. Sections for fruits and vegetables, grains, and proteins food groups, and one addressing socioemotional aspects of eating with missing teeth were included. Panel members provided constructive, positive feedback; recommendations for editing text, images, design, and content were integrated. Field-testing in the dental clinic with 27 pairs of student dentists and their patients resulted in scores of 95.7% for understandability and 96.6% for actionability, with over 85% agreement with each item. The tool was revised based on field-testing feedback. CONCLUSION: A diet education tool for older adults with tooth loss was developed using a user-centered approach, integrating the 'patient voice' and patient experiences with US dietary guidelines. Use of this tool is feasible in a dental clinic setting. Future research should explore usage in larger settings.

Giardia hinders growth by disrupting nutrient metabolism independent of inflammatory enteropathy.

Giardia lamblia (Giardia) is among the most common intestinal pathogens in children in low- and middle-income countries (LMICs). Although Giardia associates with early-life linear growth restriction, mechanistic explanations for Giardia-associated growth impairments remain elusive. Unlike other intestinal pathogens associated with constrained linear growth that cause intestinal or systemic inflammation or both, Giardia seldom associates with chronic inflammation in these children. Here we leverage the MAL-ED longitudinal birth cohort and a model of Giardia mono-association in gnotobiotic and immunodeficient mice to propose an alternative pathogenesis of this parasite. In children, Giardia results in linear growth deficits and gut permeability that are dose-dependent and independent of intestinal markers of inflammation. The estimates of these findings vary between children in different MAL-ED sites. In a representative site, where Giardia associates with growth restriction, infected children demonstrate broad amino acid deficiencies, and overproduction of specific phenolic acids, byproducts of intestinal bacterial amino acid metabolism. Gnotobiotic mice require specific nutritional and environmental conditions to recapitulate these findings, and immunodeficient mice confirm a pathway independent of chronic T/B cell inflammation. Taken together, we propose a new paradigm that Giardia-mediated growth faltering is contingent upon a convergence of this intestinal protozoa with nutritional and intestinal bacterial factors.

Novel modified quantitative index for cone-beam CT assessment of medication-related osteonecrosis of the jaw - comparative analysis with original index.

Purpose: The main research goal was to address the critical need for an objective and quantitative index to describe the nature and extent of radiographic features of medication-related osteonecrosis of the jaw (MRONJ) lesions and complement the descriptive radiographic interpretation of the lesion and its clinical assessment. Method and Materials: A retrospective review of MRONJ patients assessed at our institution was performed to compare the Composite Radiographic Index (CRI), identified from a prior scoping review, with a proposed modification, the Modified CRI index ('Mod-CRI'). The Mod-CRI index was weighted to assign a higher score for diffuse radiographic involvement of a given lesion, and delineated MRONJ lesions into those with 'high' and 'low' severity. Twenty-two MRONJ cases imaged with CBCT were retrospectively assessed with both CRI and Mod-CRI indices and the two indices were compared for their ability to quantitatively describe cone-beam computerized tomography (CBCT) radiographic features and complement the clinical staging of the MRONJ lesion. Results: There was a statistically significant association between increased clinical stage and higher mod-CRI score (p = 0.040). The Mod-CRI index sorted the patients who scored intermediate scores with the CRI (n = 15) into either the low (n = 8) or high categories (n = 7). Conclusion: The Mod-CRI index eliminated the ambiguous intermediate-category-scores in the previously published CRI index and provided greater clarity to the interpretation of a given index score. Adopting the Mod-CRI could improve MRONJ assessment and enhance communication between the radiologist and the clinician.

Cone Beam Computed Tomography (CBCT) Evaluation of Alveolar Bone Thickness and Root Angulation in Anterior Maxilla for Planning Immediate Implant Placement.

OBJECTIVE:  This retrospective study aimed to measure the labial, palatal, mesial, and distal bone thickness around maxillary central and lateral incisors and canines and height from crest to apex, using cone beam computed tomography (CBCT) images and compare the results based on gender. The second objective of the study was to measure root angulation on CBCT images and its relation with the labial cortical thicknesses.  Material and Methods: After the Institutional Review Board (IRB) approval, a total of 140 CBCT volumes were included in this study according to the set criteria. On each scan, right-side maxillary central, lateral incisors, and canine were selected for the measurements. All the measurements were done at three levels at the alveolar crest (L1), mid-root (L2), and apical region (L3) for each tooth.  Results: The Student's t-test was performed to compare the result of buccal, palatal, mesial, and distal bone thickness, angulation, and height of all subjects. Buccal alveolar bone thickness was minimum at the mid-root region, and the palatal bone thickness was minimum at the crestal region. The mesial bone thickness was minimum at the mid-root level, and distal bone thickness was minimum at the crest level. The available bone height was maximum at the lateral incisor and equal for the central incisor and canine. The canine was the most angulated tooth. CONCLUSION:  Cone beam computed tomography is a reliable imaging modality to evaluate pre-surgical immediate implant sites and measure alveolar bone thickness. The canine was the most angulated tooth with more buccal alveolar bone thickness.

Lignin deconstruction by anaerobic fungi.

Lignocellulose forms plant cell walls, and its three constituent polymers, cellulose, hemicellulose and lignin, represent the largest renewable organic carbon pool in the terrestrial biosphere. Insights into biological lignocellulose deconstruction inform understandings of global carbon sequestration dynamics and provide inspiration for biotechnologies seeking to address the current climate crisis by producing renewable chemicals from plant biomass. Organisms in diverse environments disassemble lignocellulose, and carbohydrate degradation processes are well defined, but biological lignin deconstruction is described only in aerobic systems. It is currently unclear whether anaerobic lignin deconstruction is impossible because of biochemical constraints or, alternatively, has not yet been measured. We applied whole cell-wall nuclear magnetic resonance, gel-permeation chromatography and transcriptome sequencing to interrogate the apparent paradox that anaerobic fungi (Neocallimastigomycetes), well-documented lignocellulose degradation specialists, are unable to modify lignin. We find that Neocallimastigomycetes anaerobically break chemical bonds in grass and hardwood lignins, and we further associate upregulated gene products with the observed lignocellulose deconstruction. These findings alter perceptions of lignin deconstruction by anaerobes and provide opportunities to advance decarbonization biotechnologies that depend on depolymerizing lignocellulose.

Temporomandibular Joint Imaging.

Prescriptions for imaging studies for temporomandibular disorders are based on the patient's complaint, history, and clinical findings. Appropriate selection criteria and justification for imaging examinations must be followed. Because the temporomandibular joint is composed of both hard and soft tissues, different studies are prescribed based on the clinically suspected condition. Current imaging modalities include panoramic radiographs, cone-beam computed tomography, and MRI. The entire examination must be interpreted, and the findings recorded in the patient record. No one imaging modalities is suitable for all patients. An oral and maxillofacial radiologist should be consulted when the interpretation of the study is beyond the scope of the practitioner.

Pathogenesis and Differential Diagnosis of Temporomandibular Joint Disorders.

Temporomandibular disorders (TMDs) are an umbrella term including disorders of the temporomandibular joint and muscles of the masticatory system. They are the most common nonodontogenic cause of pain in the orofacial region. A clear understanding of various conditions, underlying mechanisms, clinical presentation, and examination skills is required to effectively diagnose and manage these patients.

Temporomandibular Disorders and Dental Occlusion: What Do We Know so Far?

Throughout the recorded history in the literature of temporomandibular disorders (TMD) there have been a variety of opinions as to its primary cause. Those supporting an occlusal basis of TMD opined that occlusal dysfunction is either the primary cause for or a significant etiopathogenic factor in the causation of TMD. Most of the current literature, however, points to evidence in another direction and questions the causal role of occlusion and occlusal disharmony in TMD etiopathogenesis. Recognition of this evidence-based literature is paramount in eliminating and preventing the chances of overtreatment of patients with TMD.