The upper and lower occlusal photographs rate as some of the most challenging along with buccal retracted images. The other side of the coin, is they are two of the most valuable of the images we take. They are at the top of my list of images I show to patients, as they express an overall view of the structure and health of the teeth. There are some ways to make getting these images more predictable. One of the most important pieces is that these images be taken using mirrors and not directly. Utilizing the occlusal mirrors with handles, eliminates the challenge of gloved fingers in every shot, and the difficulty in holding the mirror int he right position and angle.
As for all of my mirror photos I utilize retractors to pull the lips out of the image. The occlusal images are one place where metal wire retractors can be an advantage as the width of the mirror can slide in between the arms of the retractor. If the patients can retract and open well enough I still prefer the plastic lip retractors. With the retractors in place I ask the patient to lift them towards their eyes for a maxillary photograph or pull down towards their belly button for the mandibular. I also help them tip the retractors so they are pulling the lips away from the labial surface of the teeth being photographed.
I place a warmed occlusal mirror against the opposite arch of teeth, making sure that the posterior of the mirror is not touching the most posterior teeth of the arch being photographed. Making sure that the mirror captures the buccal of the posterior teeth on both sides, the premolars should be the center of the image and where we focus. The angle of the shot should capture the incisal edge and labial of the central incisors. Normally I lower the f-stop for my occlusal images.