In my previous article introducing dental photography, we highlighted that a flash system is required in order to perform this process effectively. A flash system provides the essential illumination needed to obtain a detailed photo.

Flash systems have both manual and automatic settings that will determine the amount of light that is emitted. Manual flash settings can be challenging to set up and are not recommended for routine dental photography. A through the lens setting is typically considered the most appropriate flash setting for dental photography. This will commonly be abbreviated as TTL or ETTL on the camera’s flash system. Through the lens flash photography auto-adjusts the amount of light emitted by the flash to reduce the risk of underexposing or overexposing an image.

Three Common Flash Systems in Dental Photography

For clinical dental photography, the three most common flash systems utilized are the ring flash, dual flash, and softbox systems.

 

Ring Flash

Camera set up for dental photography

Dual flash

Camera set up for dental photography

Softbox system

Camera set up for dental photography

A ring flash simplifies dental clinical photography with even illumination but may obscure tooth contours crucial for diagnosis.

A dual flash system comprises two flash units flanking the lens, offering enhanced control over light direction in photography.

Two flashes, each in a reflective-coated box with a diffuser, soften light intensity, reducing harsh reflections in dental photography.

 

Ring Flash Overview

A ring flash is the simplest type of flash system to use for dental clinical photography. This device is placed on the front of the lens and projects light into the oral cavity. To attach the ring flash to the front of the lens, an adapter is usually required.

Because of the design of the ring flash, minimal shadowing will occur when using this flash system. This is beneficial for illuminating the oral cavity. However, there are times when shadowing is beneficial because it can help with determining tooth contours. Using a ring flash will prevent this information from being well-defined when the image is captured.

Ring flash set up for dental photography
Figure 1: Ring flash set up.

Dual Flash System Description

A dual flash system consists of two flash components positioned on either side of the lens. This type of flash system enables the photographer to have more control over the direction in which light is emitted.

Dual flash set up for dental photography, providing greater freedom to adjust flash angulation
Figure 2: Dual flash set up.

Because of the positioning of the flash in a dual flash system, more shadowing can occur compared to a ring flash system. This helps to reveal the contours of teeth much better and can be extremely beneficial when photographing anterior teeth. However, using a dual flash system can be challenging when taking mirror shots, as there is a much greater risk of underexposing a mirror shot when using a dual flash system.

Different reflections of light based on flash unit positioning and an underexposed mirror image captured with a dual flash system
Figure 3: Different reflections of light and underexposed mirror image using a dual flash system.

Softbox System Explanation

A third type of commonly used flash system is a softbox system. This involves the use of two distinct flash components that are mounted on either side of the camera. Each flash component is contained in a reflective-coated box with a white diffuser covering.

Softbox setup (a) and reflective coating inside the softbox (b) for dental photography
Figure 4: Softbox set up and reflective coating inside.

When the flash is triggered, light will bounce off the reflective coating inside the softbox and then be projected through the white diffuser covering. This mechanism of action diffuses the light and softens the intensity with which the light hits the subject being photographed. In doing so, a softbox will minimize the risk of the flash from causing a harsh reflection on the teeth. Due to the fact that less reflection of light occurs, softboxes are commonly used for more esthetic dental photography.

Image captured with a softbox flash setup in dental photography
Figure 5: Photo taken using a softbox flash setup.

Choosing the Right Flash System for Your Needs

Each flash system offers unique advantages and limitations in dental photography. Novice photographers may find the simplicity of a ring flash appealing, as it can yield satisfactory results for basic dental photography needs. Conversely, dual flash and softbox systems are preferred by experienced photographers for their ability to capture well-defined images with enhanced detail, particularly regarding tooth contours, resulting in aesthetically pleasing photographs.

Advanced photographers often opt for dual flash or softbox setups to achieve superior control over lighting, enabling them to mitigate harsh shadows and highlight intricate dental features effectively. While ring flashes provide straightforward illumination, they may lack the nuanced lighting control necessary for capturing highly detailed dental images desired in advanced clinical or aesthetic dentistry settings. Ultimately, the choice of flash system depends on the photographer's skill level, specific photographic requirements, and desired aesthetic outcomes.

Andy Janiga, D.M.D., practices at the Center for Dental Excellence in Nashua, N.H., and is a contributor to Spear Digest.