The SEM series: Mouth cancer

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This final image in the series depicts an SEM image of a squamous cell carcinoma (cancer) cell from a human mouth. The many blebs and microvilli on the cell's surface are clearly seen in the image.

Credit: STEVE GSCHMEISSNER/Science Photo Library

The SEM series: Actinomyces viscosus

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This issue features Actinomyces viscosus bacteria, the human and animal pathogen which colonises the mouths of 70% of adult humans. The SEM image shows the rod-shaped threads in this Gram-positive, filamentous bacterium.

Credit: Science Photo Library

The SEM series: Gingivitis

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This issue features gingivitis. The SEM image shows a large number of bacteria (yellow) in the gingiva (pink) of a human mouth.

Credit: STEVE GSCHMEISSNER/Science Photo Library

The SEM series: Dentine

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This issue features a close-up SEM view of dentine, and clearly shows the microscopic channels of the dentinal tubules.

Credit: Science Picture Co/Collection Mix: Subjects

The SEM series: Saliva

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This issue features a coloured scanning electron micrograph of saliva and the bacteria therein. The image shows the clusters of round bacteria (cocci) are linked together by strands of extracellular deoxyribonucleic acid (eDNA). The eDNA helps the biofilm to adhere to oral surfaces and contributes to antimicrobial resistance.

Credit: Science Photo Library

The SEM series: Foot and mouth

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This issue features an SEM illustration of Aphthae epizooticae virus, better known as foot-and-mouth disease. This is predominantly a disease affecting cloven-hoofed animals, and which features blisters on the inside of the mouth and on the feet. Humans can be infected with foot-and-mouth disease, but this is extremely rare. The disease is therefore a much greater threat to the agriculture industry than to human health.

Credit: SUSUMU NISHINAGA/Science Photo Library

The SEM series: Tongue bacteria

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This issue shows an SEM image of various bacteria on the surface of a human tongue.

Credit: STEVE GSCHMEISSNER/Science Photo Library

The SEM series: Enamel

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This issue features enamel prisms viewed under SEM magnification (1000×).

Credit: BSIP/Universal Images Group

The SEM series: Dental plaque

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This issue features an SEM image of plaque-forming bacteria.

Credit: STEVE GSCHMEISSNER/Science Photo Library

The SEM series: Candida albicans

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

On the cover of this issue is an SEM image of Candida albicans yeast. C. albicans is a single-celled fungus in which the cells reproduce asexually, with daughter cells budding from the parent cells. This fungus is commonly found on the skin and the mucous membranes of the mouth, digestive and respiratory tracts, and the vagina, where it is usually harmless. However, the use of antibiotics or a suppressed immune system can lead to infection. Common candida infections include oral thrush, vaginal thrush and nappy rash.

Credit: Science Photo Library

The SEM series: gingivitis

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

In this issue's cover we get up close and personal with gingivitis using SEM. The image shows a large number of bacteria (green) in the gingiva of a human mouth. Gingivitis is a reversible plaque-induced inflammation of the gingivae.

Credit: STEVE GSCHMEISSNER/Science Photo Library

The SEM series: Tongue surface

Each cover in volume 222 of the BDJ will feature a scanning electron microscope image showing bacteria or tissues found in the mouth. Scanning electron microscopes (SEMs) allow us to look at surfaces in nano-dimensions, 100 million times smaller than the human eye can see. They work by using beams of electrons instead of light rays. These electrons bounce off the surface of the material in question and are directed at a screen (like a cathode-ray TV screen) where they display a picture of the surface.

This issue features the surface of a tongue. The SEM image shows the filiform papillae covering the majority of the tongue's surface. These are the backward facing scale-like projections and sense pressure on the tongue. The round area (centre) is a fungiform papilla, which contains taste buds.

Credit: SUSUMU NISHINAGA/Science Photo Library