Primary cilia function as critical sensory organelles that mediate multiple signaling pathways,including the Hedgehog(Hh)pathway,which is essential for organ patterning and morphogenesis.Disruptions in Hh signaling ha...Primary cilia function as critical sensory organelles that mediate multiple signaling pathways,including the Hedgehog(Hh)pathway,which is essential for organ patterning and morphogenesis.Disruptions in Hh signaling have been implicated in supernumerary tooth formation and molar fusion in mutant mice.Cilk1,a highly conserved serine/threonine-protein kinase localized within primary cilia,plays a critical role in ciliary transport.Loss of Cilk1 results in severe ciliopathy phenotypes,including polydactyly,edema,and cleft palate.However,the role of Cilk1 in tooth development remains unexplored.In this study,we investigated the role of Cilk1 in tooth development.Cilk1 was found to be expressed in both the epithelial and mesenchymal compartments of developing molars.Cilk1 deficiency resulted in altered ciliary dynamics,characterized by reduced frequency and increased length,accompanied by downregulation of Hh target genes,such as Ptch1 and Sostdc1,leading to the formation of diastemal supernumerary teeth.Furthermore,in Cilk1^(-/-);PCS1–MRCS1^(△/△)mice,which exhibit a compounded suppression of Hh signaling,we uncovered a novel phenomenon:diastemal supernumerary teeth can be larger than first molars.Based on these findings,we propose a progressive model linking Hh signaling levels to sequential changes in tooth patterning:initially inducing diastemal supernumerary teeth,then enlarging them,and ultimately leading to molar fusion.This study reveals a previously unrecognized role of Cilk1 in controlling tooth morphology via Hh signaling and highlights how Hh signaling levels shape tooth patterning in a gradient-dependent manner.展开更多
The pharyngeal dental formula of Mylopharyngodon piceus is 4-5 as a rule, and the dentition isasymmetrical. It is difficult to identify each tooth in the larval dentition. In this paper the appearancepattem of tooth g...The pharyngeal dental formula of Mylopharyngodon piceus is 4-5 as a rule, and the dentition isasymmetrical. It is difficult to identify each tooth in the larval dentition. In this paper the appearancepattem of tooth germ with developmental process in this fish is described in detail. The formationpattern of the left dentition is contrasted with that of the right one. In the developmental process,the left pharyngeal dentition lacks teeth at position An3. Thus the left dentition is D-type as designatedby Nakajima(1984), while the right one is A-type.展开更多
Background: Tooth surface loss (TSL) is a progressive process arising from erosion, abrasion, attrition or abfraction. It can affect individuals of any age group: children, young adult, adults or the elderly and can c...Background: Tooth surface loss (TSL) is a progressive process arising from erosion, abrasion, attrition or abfraction. It can affect individuals of any age group: children, young adult, adults or the elderly and can compromise the health of individual tooth or the entire dentition leading to poor quality of life of the affected person. Objective: To evaluate the pattern of TSL among dental patients in a Nigerian Teaching Hospital and to assess the impact of TSL on their quality of life. Subjects and Methods: The study was a cross-sectional study among patients with TSL in a Nigerian Teaching Hospital. The Oral Health Impact Profile-14 (OHIP-14) questionnaire was used to obtain information on the impact of TSL on the quality of life of the participants. Data collected were analysed using IBM SPSS version 20. Chi-square test was used to assess association between types of TSL and quality of life of the patients. Level of significance was set at p ≤ 0.05. Results: One hundred and twenty-five patients (Males = 72;Females = 53) with tooth wear lesions participated in the study. The most common type of tooth surface loss was attrition (40%) followed by abrasion (23.2%). The highest impact of TSL on the quality of life was painful sensation strongly affecting 39 (31.2%) patients. This was followed by problem with chewing. There was no statistically significant relationship between patients’ quality of life and types of tooth surface loss. Conclusion: The most common negative impact of TSL on patient quality of life was painful sensation.展开更多
The use of leading edge with different geometrical patterns will affect the development of boundary layer flow on a flat plate and its heat transfer properties. In this work, the effects of three patterns namely saw-t...The use of leading edge with different geometrical patterns will affect the development of boundary layer flow on a flat plate and its heat transfer properties. In this work, the effects of three patterns namely saw-tooth, semicircular and slots with same wavelength and amplitude were examined. The experiments were carried out for Reynolds number based on wavelength of patterns ranging from 1540 to 3850. For all cases, after each valley, an oval shape region was formed containing a counter- rotating vortex pair. It is also shown that for the flat plate with slots, another vortex was visualized between each valley.展开更多
基金supported by the National Research Foundation of Korea(NRF)grants funded by the Korean government(MSIT)(NRF-2020R1A2C2005790,NRF2023R1A2C1007510,RS-2023-00269830,RS-2024-00438542)。
文摘Primary cilia function as critical sensory organelles that mediate multiple signaling pathways,including the Hedgehog(Hh)pathway,which is essential for organ patterning and morphogenesis.Disruptions in Hh signaling have been implicated in supernumerary tooth formation and molar fusion in mutant mice.Cilk1,a highly conserved serine/threonine-protein kinase localized within primary cilia,plays a critical role in ciliary transport.Loss of Cilk1 results in severe ciliopathy phenotypes,including polydactyly,edema,and cleft palate.However,the role of Cilk1 in tooth development remains unexplored.In this study,we investigated the role of Cilk1 in tooth development.Cilk1 was found to be expressed in both the epithelial and mesenchymal compartments of developing molars.Cilk1 deficiency resulted in altered ciliary dynamics,characterized by reduced frequency and increased length,accompanied by downregulation of Hh target genes,such as Ptch1 and Sostdc1,leading to the formation of diastemal supernumerary teeth.Furthermore,in Cilk1^(-/-);PCS1–MRCS1^(△/△)mice,which exhibit a compounded suppression of Hh signaling,we uncovered a novel phenomenon:diastemal supernumerary teeth can be larger than first molars.Based on these findings,we propose a progressive model linking Hh signaling levels to sequential changes in tooth patterning:initially inducing diastemal supernumerary teeth,then enlarging them,and ultimately leading to molar fusion.This study reveals a previously unrecognized role of Cilk1 in controlling tooth morphology via Hh signaling and highlights how Hh signaling levels shape tooth patterning in a gradient-dependent manner.
基金This project was funded by the International Cooperation of japan-Chinathe National Natural Science Foundation of China
文摘The pharyngeal dental formula of Mylopharyngodon piceus is 4-5 as a rule, and the dentition isasymmetrical. It is difficult to identify each tooth in the larval dentition. In this paper the appearancepattem of tooth germ with developmental process in this fish is described in detail. The formationpattern of the left dentition is contrasted with that of the right one. In the developmental process,the left pharyngeal dentition lacks teeth at position An3. Thus the left dentition is D-type as designatedby Nakajima(1984), while the right one is A-type.
文摘Background: Tooth surface loss (TSL) is a progressive process arising from erosion, abrasion, attrition or abfraction. It can affect individuals of any age group: children, young adult, adults or the elderly and can compromise the health of individual tooth or the entire dentition leading to poor quality of life of the affected person. Objective: To evaluate the pattern of TSL among dental patients in a Nigerian Teaching Hospital and to assess the impact of TSL on their quality of life. Subjects and Methods: The study was a cross-sectional study among patients with TSL in a Nigerian Teaching Hospital. The Oral Health Impact Profile-14 (OHIP-14) questionnaire was used to obtain information on the impact of TSL on the quality of life of the participants. Data collected were analysed using IBM SPSS version 20. Chi-square test was used to assess association between types of TSL and quality of life of the patients. Level of significance was set at p ≤ 0.05. Results: One hundred and twenty-five patients (Males = 72;Females = 53) with tooth wear lesions participated in the study. The most common type of tooth surface loss was attrition (40%) followed by abrasion (23.2%). The highest impact of TSL on the quality of life was painful sensation strongly affecting 39 (31.2%) patients. This was followed by problem with chewing. There was no statistically significant relationship between patients’ quality of life and types of tooth surface loss. Conclusion: The most common negative impact of TSL on patient quality of life was painful sensation.
文摘The use of leading edge with different geometrical patterns will affect the development of boundary layer flow on a flat plate and its heat transfer properties. In this work, the effects of three patterns namely saw-tooth, semicircular and slots with same wavelength and amplitude were examined. The experiments were carried out for Reynolds number based on wavelength of patterns ranging from 1540 to 3850. For all cases, after each valley, an oval shape region was formed containing a counter- rotating vortex pair. It is also shown that for the flat plate with slots, another vortex was visualized between each valley.