Timing of Mouse Molar Formation Is Independent of Jaw Length Including Retromolar Space
For humans and other mammals to eat effectively, teeth must develop properly inside the jaw. Deciphering craniodental integration is central to explaining the timely formation of permanent molars, including third molars which are often impacted in humans, and to clarifying how teeth and jaws fit, fu...
| Main Authors: | , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-03-01
|
| Series: | Journal of Developmental Biology |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2221-3759/9/1/8 |
| _version_ | 1827697861018517504 |
|---|---|
| author | Daisy (Jihyung) Ko Tess Kelly Lacey Thompson Jasmene K. Uppal Nasim Rostampour Mark Adam Webb Ning Zhu George Belev Prosanta Mondal David M. L. Cooper Julia C. Boughner |
| author_facet | Daisy (Jihyung) Ko Tess Kelly Lacey Thompson Jasmene K. Uppal Nasim Rostampour Mark Adam Webb Ning Zhu George Belev Prosanta Mondal David M. L. Cooper Julia C. Boughner |
| author_sort | Daisy (Jihyung) Ko |
| collection | DOAJ |
| description | For humans and other mammals to eat effectively, teeth must develop properly inside the jaw. Deciphering craniodental integration is central to explaining the timely formation of permanent molars, including third molars which are often impacted in humans, and to clarifying how teeth and jaws fit, function and evolve together. A factor long-posited to influence molar onset time is the jaw space available for each molar organ to form within. Here, we tested whether each successive molar initiates only after a minimum threshold of space is created via jaw growth. We used synchrotron-based micro-CT scanning to assess developing molars in situ within jaws of C57BL/6J mice aged E10 to P32, encompassing molar onset to emergence. We compared total jaw, retromolar and molar lengths, and molar onset times, between upper and lower jaws. Initiation time and developmental duration were comparable between molar upper and lower counterparts despite shorter, slower-growing retromolar space in the upper jaw, and despite size differences between upper and lower molars. Timing of molar formation appears unmoved by jaw length including space. Conditions within the dental lamina likely influence molar onset much more than surrounding jaw tissues. We theorize that molar initiation is contingent on sufficient surface area for the physical reorganization of dental epithelium and its invagination of underlying mesenchyme. |
| first_indexed | 2024-03-10T13:18:41Z |
| format | Article |
| id | doaj.art-ba61550e83dc488088f44b2c1332c44f |
| institution | Directory Open Access Journal |
| issn | 2221-3759 |
| language | English |
| last_indexed | 2024-03-10T13:18:41Z |
| publishDate | 2021-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Journal of Developmental Biology |
| spelling | doaj.art-ba61550e83dc488088f44b2c1332c44f2023-11-21T10:12:57ZengMDPI AGJournal of Developmental Biology2221-37592021-03-0191810.3390/jdb9010008Timing of Mouse Molar Formation Is Independent of Jaw Length Including Retromolar SpaceDaisy (Jihyung) Ko0Tess Kelly1Lacey Thompson2Jasmene K. Uppal3Nasim Rostampour4Mark Adam Webb5Ning Zhu6George Belev7Prosanta Mondal8David M. L. Cooper9Julia C. Boughner10Department of Anatomy, Physiology & Pharmacology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, CanadaDepartment of Anatomy, Physiology & Pharmacology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, CanadaDepartment of Anatomy, Physiology & Pharmacology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, CanadaDepartment of Anatomy, Physiology & Pharmacology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, CanadaDepartment of Anatomy, Physiology & Pharmacology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, CanadaCanadian Light Source, University of Saskatchewan, 44 Innovation Boulevard, Saskatoon, SK S7N 2V3, CanadaCanadian Light Source, University of Saskatchewan, 44 Innovation Boulevard, Saskatoon, SK S7N 2V3, CanadaCanadian Light Source, University of Saskatchewan, 44 Innovation Boulevard, Saskatoon, SK S7N 2V3, CanadaClinical Research Support Unit, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, CanadaDepartment of Anatomy, Physiology & Pharmacology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, CanadaDepartment of Anatomy, Physiology & Pharmacology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, CanadaFor humans and other mammals to eat effectively, teeth must develop properly inside the jaw. Deciphering craniodental integration is central to explaining the timely formation of permanent molars, including third molars which are often impacted in humans, and to clarifying how teeth and jaws fit, function and evolve together. A factor long-posited to influence molar onset time is the jaw space available for each molar organ to form within. Here, we tested whether each successive molar initiates only after a minimum threshold of space is created via jaw growth. We used synchrotron-based micro-CT scanning to assess developing molars in situ within jaws of C57BL/6J mice aged E10 to P32, encompassing molar onset to emergence. We compared total jaw, retromolar and molar lengths, and molar onset times, between upper and lower jaws. Initiation time and developmental duration were comparable between molar upper and lower counterparts despite shorter, slower-growing retromolar space in the upper jaw, and despite size differences between upper and lower molars. Timing of molar formation appears unmoved by jaw length including space. Conditions within the dental lamina likely influence molar onset much more than surrounding jaw tissues. We theorize that molar initiation is contingent on sufficient surface area for the physical reorganization of dental epithelium and its invagination of underlying mesenchyme.https://www.mdpi.com/2221-3759/9/1/8tooth developmentmolar initiationcraniodental integration3D imagingsynchrotron scanning |
| spellingShingle | Daisy (Jihyung) Ko Tess Kelly Lacey Thompson Jasmene K. Uppal Nasim Rostampour Mark Adam Webb Ning Zhu George Belev Prosanta Mondal David M. L. Cooper Julia C. Boughner Timing of Mouse Molar Formation Is Independent of Jaw Length Including Retromolar Space Journal of Developmental Biology tooth development molar initiation craniodental integration 3D imaging synchrotron scanning |
| title | Timing of Mouse Molar Formation Is Independent of Jaw Length Including Retromolar Space |
| title_full | Timing of Mouse Molar Formation Is Independent of Jaw Length Including Retromolar Space |
| title_fullStr | Timing of Mouse Molar Formation Is Independent of Jaw Length Including Retromolar Space |
| title_full_unstemmed | Timing of Mouse Molar Formation Is Independent of Jaw Length Including Retromolar Space |
| title_short | Timing of Mouse Molar Formation Is Independent of Jaw Length Including Retromolar Space |
| title_sort | timing of mouse molar formation is independent of jaw length including retromolar space |
| topic | tooth development molar initiation craniodental integration 3D imaging synchrotron scanning |
| url | https://www.mdpi.com/2221-3759/9/1/8 |
| work_keys_str_mv | AT daisyjihyungko timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT tesskelly timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT laceythompson timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT jasmenekuppal timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT nasimrostampour timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT markadamwebb timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT ningzhu timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT georgebelev timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT prosantamondal timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT davidmlcooper timingofmousemolarformationisindependentofjawlengthincludingretromolarspace AT juliacboughner timingofmousemolarformationisindependentofjawlengthincludingretromolarspace |