Visualization of Endogenous Hypochlorite in Drug-Induced Liver Injury Mice via a Bioluminescent Probe Combined with Firefly Luciferase mRNA-Loaded Lipid Nanoparticles.

Drug-induced liver injury (DILI) is a common liver disease with a high rate of morbidity, and its pathogenesis is closely associated with the overproduction of highly reactive hypochlorite (ClO-) in the liver. However, bioluminescence imaging of endogenous hypochlorite in nontransgenic natural mice remains challenging. Herein, to address this issue, we report a strategy for imaging ClO- in living cells and DILI mice by harnessing a bioluminescent probe formylhydrazine luciferin (ClO-Luc) combined with firefly luciferase (fLuc) mRNA-loaded lipid nanoparticles (LNPs). LNPs could efficiently deliver fLuc mRNA into living cells and in vivo, expressing abundant luciferase in the cytoplasm in situ. In the presence of ClO-, probe ClO-Luc locked by formylhydrazine could release cage-free d-luciferin through oxidation and follow-up hydrolysis reactions, further allowing for bioluminescence imaging. Moreover, based on the luciferase-luciferin system, it was able to sensitively and selectively detect ClO- in vitro with a limit of detection of 0.59 µM and successfully monitor the endogenous hypochlorite generation in the DILI mouse model for the first time. We postulate that this work provides a new method to elucidate the roles of ClO- in related diseases via bioluminescence imaging.

Effectiveness of mHealth intervention for trismus exercise in patients with head and neck cancer undergoing proton and heavy ion therapy: a randomized control trial.

PURPOSE: This study aimed to compare the effects of a mobile health intervention based on social cognitive theory with standard care on maximal mouth opening, exercise compliance, and self-efficacy in patients receiving proton and heavy ion therapy for head and neck cancer. METHODS: This open-label, parallel-group, randomized, superiority trial involved a self-developed "Health Enjoy System" intervention. We assessed maximal mouth opening, exercise compliance, and self-efficacy at baseline (T0), post-treatment (T1), and at 1 month (T2) and 3 months (T3) after radiotherapy. Generalized estimating equations were used to analyze differences between the groups over time, with results reported as P values and 95% confidence intervals (CIs). RESULTS: The study included 44 participants. At T3, the intervention group showed a 6 mm greater increase in maximal interincisal opening than the control group (mean difference = 6.0, 95% CI = 2.4 to 9.5, P = 0.001). There was also a significant difference in exercise compliance between the groups (mean difference = 31.7, 95% CI = 4.6 to 58.8, P = 0.022). However, no significant difference in self-efficacy was found between the groups. CONCLUSION: This study demonstrated that an mHealth intervention incorporating behavior change theory could effectively enhance or maintain maximal mouth opening in patients undergoing proton and heavy ion therapy for head and neck cancer in China. This approach provides valuable support during and after treatment. TRIAL REGISTRATION: ChiCTR: ChiCTR2300067550. Registered 11 Jan 2023.

Benzimidazolone-Dioxazine Pigments-Based Conjugated Polymers for Organic Field-Effect Transistor.

Molecules based on benzimidazolone-dioxazine are known as blue/violet pigments and have been commercialized for decades. However, unfavorable solubility limits the application of these structures as building blocks of conjugated polymers despite their low band gaps. Herein, a series of donor-acceptor conjugated polymers containing soluble benzimidazolone-dioxazine structures as the acceptors and oligothiophene as donors are synthesized and investigated. With increasing numbers of thiophene rings, the steric hindrance diminishes and high molecular weight polymers can be achieved, leading to an improved performance in organic field effect transistor devices. The hole mobility of polymers with three to six thiophene units is in the order of 10-1 cm2 V-1 s -1 . Among all the polymers, polymer P3 with three thiophene units between benzimidazolone-dioxazine structures shows the best hole mobility of 0.4 cm2 V-1 s -1 . Grazing-incidence wide-angle X-ray scattering results reveal that the high mobility of organic field-effect transistors (OFETs) can be accredited by matched donor-acceptor packing in the solid thin films.

Accurate calculation of tunneling splittings in water clusters using path-integral based methods.

Tunneling splittings observed in molecular rovibrational spectra are significant evidence for tunneling motion of hydrogen nuclei in water clusters. Accurate calculations of the splitting sizes from first principles require a combination of high-quality inter-atomic interactions and rigorous methods to treat the nuclei with quantum mechanics. Many theoretical efforts have been made in recent decades. This Perspective focuses on two path-integral based tunneling splitting methods whose computational cost scales well with the system size, namely, the ring-polymer instanton method and the path-integral molecular dynamics (PIMD) method. From a simple derivation, we show that the former is a semiclassical approximation to the latter, despite that the two methods are derived very differently. Currently, the PIMD method is considered to be an ideal route to rigorously compute the ground-state tunneling splitting, while the instanton method sacrifices some accuracy for a significantly smaller computational cost. An application scenario of such a quantitatively rigorous calculation is to test and calibrate the potential energy surfaces of molecular systems by spectroscopic accuracy. Recent progress in water clusters is reviewed, and the current challenges are discussed.

Enhanced Lip-Contour During Facial Scan for 3D DSD and Implant Planning: A Blue Screen Approach.

When obtaining 3-dimensional (3D) facial images for digital smile design (DSD) and dental implant planning, inaccuracies may frequently be introduced by distortion in the region between the lips' vermilion border and the teeth. The present clinical technique aimed to reduce such deformation during face scanning, thereby facilitating 3D DSD. This is also essential to plan bone reduction with precision for implant reconstructions. A custom-made silicone matrix acting as a blue screen provided reliable support for 3D visualization of facial images in a patient requiring a new maxillary screw-retained implant-supported fixed complete denture. Imperceptible volumetric changes were registered in the facial tissues when the silicone matrix was added. The usual deformation of the lip vermilion border originating in face scans was overcome by applying blue-screen technology with a silicone matrix. Reproducing the vermilion border of the lip contour accurately may offer improved communication and visualization for 3D DSD. The silicone matrix was a practical approach that acted as a blue screen to display the transition from lips to teeth with satisfactory precision. Implementing blue-screen technology in reconstructive dentistry might increase predictability by reducing errors when scanning objects with challenging-to-capture surfaces.

The impact of smoking on periodontitis patients' GCF/serum cytokine profile both before and after periodontal therapy: a meta-analysis.

BACKGROUND: Smoking is an established modifying factor for the host immune response of periodontitis patients. However, its exact influence remains unclear. We aimed to compare the cytokine profile of periodontitis patients with and without smoking habits both before and after periodontal therapy to preliminarily explore its influence on the host immune response to periodontitis. METHODS: The protocol of the present meta-analysis was registered in the International Prospective Register of Systematic Reviews (PROSPERO) under the code CRD42021255656. Meta-analysis was performed for each cytokine if at least three studies were included. We synthesized the evidence to compare the cytokine profile of periodontitis with and without smoking both in gingival cervical fluid (GCF) and serum to explore the impact of smoking on periodontitis both locally and systemically. Moreover, we also compared the cytokine profile of the two groups of patients after periodontal therapy to explore the effect of smoking on the outcome of periodontal therapy. RESULTS: Fifteen studies were included in this meta-analysis. We found that there was no significant difference between the two groups of patients in the baseline cytokine profile. However, after periodontal therapy, smoking periodontitis patients showed significantly higher IL-1ß levels in their GCF than nonsmoking patients. DISCUSSION: There was no significant difference between smoking and nonsmoking periodontitis patients in the baseline cytokine profile. However, after periodontal therapy, smoking periodontitis patients showed significantly higher IL-1ß levels in their GCF than nonsmoking patients, which indicates that smoking may impair the response of periodontitis to periodontal treatment.

Modes of adhesion of two Janus nanoparticles on the outer or inner side of lipid vesicles.

Using molecular dynamics simulations of a coarse-grained model, in conjunction with the weighted histogram analysis method, the adhesion modes of two spherical Janus nanoparticles (NPs) on the outer or inner side of lipid vesicles are explored. In particular, the effects of the area fraction, J, of the NPs that interact attractively with lipid head groups, the adhesion strength and the size of the NPs on their adhesion modes are investigated. The NPs are found to exhibit two main modes of adhesion when adhered to the outer side of the vesicle. In the first mode, which occurs at relatively low values of J, the NPs are apart from each other. In the second mode, which occurs at higher values of J, the NPs form an in-plane dimer. Janus NPs, which adhere to the inner side of the vesicle, are always found to be apart from each other, regardless of the value of J and their diameter.

Collective motion of cells modeled as ring polymers.

In this article, we use a coarse-grained model of disjoint semi-flexible ring polymers to investigate computationally the spatiotemporal collective behavior of cell colonies. A ring polymer in this model is self-propelled by a motility force along the cell's polarity, which depends on its historical kinetics. Despite the repulsive interaction between the cells, a collective behavior sets in as a result of cells pushing against each other. This cooperative motion emerges as the amplitude of the motility force is increased and/or their areal density is increased. The degree of collectivity, characterized by the average cluster size, the velocity field order parameter, and the polarity field nematic order parameter, is found to increase with increasing the amplitude of the motility force and area coverage of the cells. Furthermore, the degree of alignment exhibited by the cell velocity field within a cluster is found to be stronger than that exhibited by the cell polarity. Comparison between the collective behavior of elongated cells and that of circular cells, at the same area coverage and motility force, shows that elongated cells exhibit a stronger collective behavior than circular cells, in agreement with earlier studies of self-propelled anisotropic particles. An investigation of two-cell collisions shows that while two clustered cells move in tandem, their polarities are misaligned. As such the cells push against each other while moving coherently.

When polymerization meets coordination-driven self-assembly: metallo-supramolecular polymers based on supramolecular coordination complexes.

Polymers have greatly changed and are still changing the way we live ever since, and the construction of novel polymers as functional materials remains an attractive topic in polymer science and related areas. During the past few years, the marriage of discrete supramolecular coordination complexes (SCCs), including two-dimensional (2D) metallacycles and three-dimensional (3D) metallacages, and polymers gave rise to two novel types of metallo-supramolecular polymers, i.e., metallacycle/metallacage-cored star polymers (MSPs) and metallacycle/metallacage-crosslinked polymer networks (MPNs), which has attracted increasing attention and emerged as an exciting new research direction in polymer chemistry. Attributed to their well-defined and diverse topological architectures as well as the unique dynamic features of metallacycles/metallacages as cores or crosslinks, these novel polymers have shown extensive applications. In this review, aiming at providing a practical guide to this emerging area, the introduction of synthetic strategies towards MSPs and MPNs will be presented. In addition, their wide applications in areas such as functional materials, molecular sieving, drug delivery, bacterial killing and bioimaging are also discussed.

Food emulsifier polysorbate 80 promotes the intestinal absorption of mono-2-ethylhexyl phthalate by disturbing intestinal barrier.

Di-2-ethylhexyl phosphate (DEHP) and its main toxic metabolite mono-2-ethylhexyl phthalate (MEHP) are the typical endocrine disrupting chemicals (EDCs) and widely affect human health. Our previous research reported that synthetic nonionic dietary emulsifier polysorbate 80 (P80, E433) had the promotional effect on the oral absorption of DEHP in rats. The aim of this study was to explore its mechanism of promoting oral absorption, focusing on the mucus barrier and mucosal barrier of the small intestine. A small molecule fluorescent probe 5-aminofluorescein-MEHP (MEHP-AF) was used as a tracker of MEHP in vivo and in vitro. First of all, we verified that P80 promoted the bioavailability of MEHP-AF in the long-term and low-dose exposure of MEHP-AF with P80 as a result of increasing the intestinal absorption of MEHP-AF. Afterwards, experimental results from Western blot, qPCR, immunohistochemistry, and immunofluorescence showed that P80 decreased the expression of proteins (mucus protein mucin-2, tight junction proteins claudin-1 and occludin) related to mucus barrier and mucosal barrier in the intestine, changed the integrity of intestinal epithelial cell, and increased the permeability of intestinal epithelial mucosa. These results indicated that P80 promoted the oral absorption of MEHP-AF by altering the intestinal mucus barrier and mucosal barrier. These findings are of great importance for assessing the safety risks of some food emulsifiers and clarifying the absorption mechanism of chemical pollutants in food, especially for EDCs.

Accuracy of dynamic navigation in implant surgery: A systematic review and meta-analysis.

OBJECTIVE: To assess the accuracy of dynamic computer-assisted implant surgery. MATERIALS AND METHODS: An electronic search up to March 2020 was conducted using PubMed, Embase, and the Cochrane Central Register of Controlled Trial to identify studies using dynamic navigation in implant surgery, and additional manual search was performed as well. Clinical trials and model studies were selected. The primary outcome was accuracy. A single-arm meta-analysis of continuous data was conducted. Meta-regression was utilized for comparison on study design, guidance method, jaw, and systems. RESULTS: Ten studies, four randomized controlled trials (RCT) and six prospective studies, met the inclusion criteria. A total of 1,298 drillings and implants were evaluated. The meta-analysis of the accuracy (five clinical trials and five model studies) revealed average global platform deviation, global apex deviation, and angular deviation were 1.02 mm, 95% CI (0.83, 1.21), 1.33 mm, 95% CI (0.98, 1.67), and 3.59°, 95% CI (2.09, 5.09). Meta-regression shown no difference between model studies and clinical trials (p = .295, 0.336, 0.185), drilling holes and implant (p = .36, 0.279, 0.695), maxilla and mandible (p = .875, 0.632, 0.281), and five different systems (p = .762, 0.342, 0.336). CONCLUSION: Accuracy of dynamic computer-aided implant surgery reaches a clinically acceptable range and has potential in clinical usage, but more patient-centered outcomes and socio-economic benefits should be reported.

Oral microbial profile variation during canine ligature-induced peri-implantitis development.

BACKGROUND: Dental implants have become well-established in oral rehabilitation for fully or partially edentulous patients. However, peri-implantitis often leads to the failure of dental implants. The aim of this study was to understand the core microbiome associated with peri-implantitis and evaluate potential peri-implantitis pathogens based on canine peri-implantitis model. RESULTS: In this study, three beagle dogs were used to build peri-implantitis models with ligature-induced strategy. The peri-implant sulcular fluids were collected at four different phases based on disease severity during the peri-implantitis development. Microbial compositions during peri-implantitis development were monitored and evaluated. The microbes were presented with operational taxonomic unit (OTU) classified at 97% identity of the high-throughput 16S rRNA gene fragments. Microbial diversity and richness varied during peri-implantitis. At the phylum-level, Firmicutes decreased and Bacteroides increased during peri-implantitis development. At the genus-level, Peptostreptococcus decreased and Porphyromonas increased, suggesting peri-implantitis pathogens might be assigned to these two genera. Further species-level and co-occurrence network analyses identified several potential keystone species during peri-implantitis development, and some OTUs were potential peri-implantitis pathogens. CONCLUSION: In summary, canine peri-implantitis models help to identify several potential keystone peri-implantitis associated species. The canine model can give insight into human peri-implantitis associated microbiota.

Identification of Saliva Proteins of the Spider Mite Tetranychus evansi by Transcriptome and LC-MS/MS Analyses.

The spider mite Tetranychus evansi has a remarkable ability to suppress and manipulate plant defenses, which makes it an ideal model to investigate plant-herbivores interactions. In this study, a de novo assembly of the transcriptome of T. evansi is performed and the proteins in its secreted saliva by LC-MS/MS are characterized. A total of 29 365 unigenes are assembled and 136 saliva proteins are identified. Comparative analysis of the saliva proteins in T. evansi, T. truncatus, and T. urticae shows that 64 protein groups are shared by at least two Tetranychus species, and 52 protein groups are specifically identified in T. evansi. In addition, some saliva proteins are common in arthropod species, while others are species-specific. These results will help to elucidate the molecular mechanisms by which T. evansi modulates plant defenses.

Intubation of non-difficult airways using video laryngoscope versus direct laryngoscope: a randomized, parallel-group study.

BACKGROUND: The video laryngoscope is recommended for intubating difficult airways. The present study aimed to determine whether the video laryngoscope can further improve intubation success rates compared with the direct laryngoscope in patients with non-difficult airways. METHODS: In total, 360 patients scheduled for elective abdominal surgeries were randomly assigned to undergo intubation using either a video laryngoscope (n = 179) or a direct laryngoscope (n = 181). The following parameters were measured: mouth opening; thyromental distance; sternomental distance; shape angle of the tracheal catheter; and glottic exposure grade. RESULTS: The percentage of patients with level I-II of total glottic exposure in the video laryngoscope group was 100% versus 63.5% in the direct laryngoscope group (P < 0.001). The one-attempt success rate of intubation was 96.1% using a video laryngoscope versus 90.1% using a direct laryngoscope (P = 0.024). The intubation success rate using a video laryngoscope was 100% versus 94.5% using a direct laryngoscope (P = 0.004). Immediate oropharyngeal injury occurred in 5.1% of patients intubated using a direct laryngoscope versus 1.1% using a video laryngoscope (P = 0.033). On postoperative day 1, obvious hoarseness was exhibited by 7.9% of patients intubated using a direct laryngoscope versus 2.8% using a video laryngoscope (P = 0.035). The grade of glottic exposure and catheter shape angle were independent risk factors for tracheal intubation failure. Thyromental distance, shape angle, glottic exposure time, and surgical position were independent risk factors for postoperative complications. Thyromental distance and glottic exposure time were independent risk factors for complications lasting > 2 days. CONCLUSIONS: Intubation using a video laryngoscope yielded significantly higher intubation success rates and significantly fewer postoperative complications than direct laryngoscopy in patients with non-difficult airways. TRIAL REGISTRATION: Chinese Clinical Trial Registry. No: ChiCTR-IOR-16009023 . Prospective registration.

The gut microbiota of hand, foot and mouth disease patients demonstrates down-regulated butyrate-producing bacteria and up-regulated inflammation-inducing bacteria.

AIM: This study explored the gut microbiota of children with hand, foot and mouth disease (HFMD). METHODS: We enrolled 15 cases with HFMD admitted to the West China Second Hospital, Sichuan University, China, from July to September 2016 at a median age of three years. The controls were 15 healthy children of a similar age who underwent routine health examinations at the hospital during the same period. Gut microbiota was analysed using high throughput 16S ribosomal deoxyribonucleic acid sequencing. RESULTS: The gut microbiota in the HFMD patients was distinct from the controls. Compared with the controls, the composition of gut microbiota in the HFMD cases represented a reduction of two butyrate-producing bacteria, Ruminococcus (0.73 ± 1.28 versus 7.78 ± 20.01, p = 0.026) and Roseburia (0.67 ± 1.69 versus 1.61 ± 3.27, p = 0.024) and an up-regulation of Escherichia (5.26 ± 10.50 versus 1.59 ± 5.90,p < 0.01) and Enterococcus (4.12 ± 12.49 versus 0.12 ± 0.41, p = 0.015). CONCLUSION: The dysbiosis of gut microbiota of the HFMD cases included a reduction of butyrate-producing bacteria and an up-regulation of inflammation-inducing bacteria. These may have impaired the intestinal biological mucosal barrier and host immune functions, promoting the invasion of the enterovirus.

Association of IL-28B, TBX21 gene polymorphisms and predictors of virological response for chronic hepatitis C.

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease. The outcomes of both spontaneous HCV clearance and response to therapy depend on both viral and host factors. To investigate the influence of polymorphisms of IL-28B rs12979860 and TBX21 rs17250932, rs4794067 as well as viral factors (HCV genotype, F protein) on the outcome of HCV infection, we genotyped 565 patients with chronic HCV infection, 191 patients spontaneously resolved from HCV infection, 359 healthy controls and 383 treatment-naïve CHC patients with pegylated interferon-α and ribavirin (PEG IFN-α/RBV). Results showed that TBX21 rs4794067 variant genotypes significantly correlated with increased risk of HCV chronic infection (dominant model: OR = 5.690, 95% CI = 2.024-16.000) and susceptibility (dominant model: OR = 5.658, 95% CI = 2.514-12.735). We also found that the rs12979860, rs2227982 and rs36084323 polymorphisms showed no significant associations with susceptibility or spontaneous clearance of HCV in the anti-F antibody subgroup; however, the anti-F antibody positive subgroup might show an increased risk of N-SVR (all P < 0.001). Our results demonstrate that variant factors in both the host and pathogen are commonly important for HCV clearance. In addition rs4794067 and F protein status may be strong predictive markers in the Chinese population.

Molecularly imprinted polymer based diffusive gradients in thin-films for in situ selective sampling and determination of ciprofloxacin.

A technique of diffusive gradients in thin films with ciprofloxacin-molecularly imprinted polymers as the binding agent was developed for in situ selective sampling and measurement of ciprofloxacin in water. The ciprofloxacin uptake by the method increased linearly with time (r2  = 0.998) with a recovery of 96.8% in synthetic solution. The method performance was not dependent on solution pH over the pH range of 2-11 and ionic strength range from 1 × 10-4 to 0.5 mol/L sodium nitrate. The binding agent has a higher adsorption affinity for ciprofloxacin than for other drug residues, such as norfloxacin, chloramphenicol, and malachite green. The concentration of ciprofloxacin in river water determined by this method was 0.52 ± 0.3 µg/L, and the recoveries of ciprofloxacin were 96.1-102.0%.

The effect of photodynamic therapy on pathogenic bacteria around peri-implant sulcus and in the cavity between abutment and implant after healing phase: A prospective clinical study.

OBJECTIVES: To compare levels of pathogens from peri-implant sulcus versus abutment screw cavities after photodynamic therapy. MATERIAL AND METHODS: Twenty patients were included. Photodynamic therapy (PDT) was applied both in sulcus and cavities after sampling following suprastructures loading, and repeated after 2 weeks. Two samples each containing four paper points were collected for each implant at baseline, 2 weeks, 3 months: (i) peri-implant sulcus and (ii) abutment screw cavities. Seventy-five percent ethanol was applied in another 20 patients as the control group in the same way. qPCR was used to quantify periodontal pathogens: Porphyromonas gingivalis, Fusobacterium nucleatum, Streptococcus mutans. RESULTS: PDT showed a better bacterial reduction than ethanol. P. g. and F. n. were most frequently detected, while less for S. m. P. gingivalis' proportion from both sites was significantly higher than the other two bacteria (P < 0.05), except for 2 weeks' peri-implant sulcus sample. Bacteria counts from abutment screw cavities were always less than those from peri-implant sulcus and was significantly lower for total bacteria at 3 months (P < 0.05). Total bacterial from abutment screw cavities significantly reduced at 3 months compared to baseline (P < 0.05). CONCLUSIONS: PDT appears to be effective in bacterial reduction compared to ethanol and can reduce P. gingivalis with short time intervals, as well as decreasing total bacteria counts within abutment screw cavities in the long run, suggesting PDT an effective way sterilizing inner surface of oral implant suprastrutures. Lasers Surg. Med. 50:433-439, 2018. © 2018 Wiley Periodicals, Inc.

Production of Composite Scaffold Containing Silk Fibroin, Chitosan, and Gelatin for 3D Cell Culture and Bone Tissue Regeneration.

BACKGROUND Bone tissue engineering, a powerful tool to treat bone defects, is highly dependent on use of scaffolds. Both silk fibroin (SF) and chitosan (Cs) are biocompatible and actively studied for reconstruction of tissue engineering. Gelatin (Gel) is also widely applied in the biomedical field due to its low antigenicity and physicochemical stability. MATERIAL AND METHODS In this study, 4 different types of scaffolds were constructed - SF, SF/Cs, SF/Gel, and SF/Cs/Gel - and we compared their physical and chemical properties as well as biological characterization of these scaffolds to determine the most suitable scaffold for use in bone regeneration. First, these scaffolds were produced via chemical cross-linking method and freeze-drying technique. Next, the characterization of internal structure was studied using scanning electron microscopy and the porosity was evaluated by liquid displacement method. Then, we compared physicochemical properties such as water absorption rate and degradation property. Finally, MC3T3-E1 cells were inoculated on the scaffolds to study the biocompatibility and osteogenesis of the three-dimensional (3D) scaffolds in vitro. RESULTS The composite scaffold formed by all 3 components was the best for use in bone regeneration. CONCLUSIONS We conclude that the best scaffold among the 4 studied for MC3T3-E1 cells is our SF/Cs/Gel scaffold, suggesting a new choice for bone regeneration that can be used to treat bone defects or fractures in clinical practice.

Current concepts in odontohypophosphatasia form of hypophosphatasia and report of two cases.

BACKGROUND: Hypophosphatasia is a rare inherited disease derived from mutations in tissue non-specific alkaline phosphatase genes, with typical oral symptoms including short root anomaly and dysplasia of dentin or cementum. CASE PRESENTATION: Two young female patients presented with short root anomaly with a history of premature loss of deciduous and/or permanent teeth. The laboratory and imaging investigations were performed. One case was diagnosed as odontohypophosphatasia concurrent with hyperthyroidism, the other was odontohypophosphatasia concurrent with multiple radicular cysts. CONCLUSION: This report presents two cases of odontohypophosphatasia, a rare disease which is difficult to be diagnosed, and highlights that the history of premature loss of deciduous and/or permanent teeth, oral manifestation and laboratory tests are crucial for clinical diagnosis.