1	Maxillary Arch	9	Mandibular Arch
2	Central and lateral Incisors	10	Central and lateral incisors
3	Right Cuspid	11	Right Cuspid
4	Right Bicuspid	12	Right Bicuspid
5	Right Molars	13	Right Molars
6	Left Cuspid	14	Left Cuspid
7	Left Bicuspid	15	Left Bicuspid
8	Left Molars	16	Left Molars
		17	Bitewings

 

Maxillary Central  and Lateral Incisors Begin the full mouth series with the maxillary central incisor region. Patients usually tolerate this film easily. The film is inserted into the holder in a vertical orientation. The beam should pass perpendicular to the film plane and the film should be at a 90º angle to the interproximal area of the maxillary central incisors. The film is placed well into the palatal region, in the area of the second bicuspid. If it is too close to the teeth, the curve of the palate may prevent the most parallel placement of the film or sensor.      Maxillary Cuspid For the maxillary cuspids, the film is placed into the holder in a vertical orientation. The cuspid is centered on the film and it is placed well into the palate. The central x-ray beam is perpendicular to the film and at a right angle to the long axis of the tooth. The mesial contact should be open, but often the distal contact is unavoidably overlapped. The next film will display the distal contact area.   Maxillary Bicuspid For the maxillary bicuspids, the film is placed in the holder in a horizontal orientation. The contact between the first and second premolar is centered on the film with the central x-ray beam perpendicular to the film. The contacts for the distal of the canine through the distal of the second premolar should be open. Sometimes, a cotton roll will need to be placed between the bite block and the mandibular teeth opposing in occlusion. This will stabilize the bite and keep the block from rotating because of the occlusion of the canine.

Maxillary Molars For the maxillary molars, the film is placed in the holder in a horizontal orientation. The second molar is centered on the film with the central x-ray beam perpendicular to the film. The contacts of the first, second, and third molars should be open. The third molar region should be included in this film even if the tooth is not present.   In practice, it may not always be possible to place the film or sensor parallel to the teeth.  It the event that a non parallel technique is necessary, refer to the shadow casting page to learn how to  split the angle between the tooth and the film.

Mandibular Anteriors

For the mandibular anteriors, the film is placed in the holder in a vertical orientation. The mandibular central incisors are centered on the film with the central x-ray beam perpendicular to the film. The contact between the two central incisors should be open. The film should be placed as far into the patient's mouth as possible without causing discomfort, usually as far back as the second premolar. The tongue is moved back and must not be between the film and the teeth or it will show on the radiograph. The lateral incisors should be visible in this film as well. Two smaller films may be used if the patient's mandible is unusually narrow.

Mandibular Cuspid

For the mandibular cuspids, the film is placed in the holder in a vertical orientation. The mandibular canine is centered on the film with the central x-ray beam perpendicular to the film. The mesial contact of the lateral and the distal of the first premolar should be present in this film, with the mesial and distal contact of the canine open. The tongue should be mildly displaced so the film can be inserted into the floor of the mouth and far enough away from the teeth so that the film doesn't bend.   The canine shot is very rarely accomplished keeping the film parallel to the tooth because of the shape of the space available.  For this reason,  it is generally more practical to place the film at a steep incisal/apical angle and use the angle splitting technique to aim the beam.

Mandibular Premolars and Molars

For mandibular premolars, the film is placed in the holder in a horizontal orientation. The contact between the second premolar and the first molar is centered on the film. The central beam should be perpendicular with the long axis of the tooth. The film should contain the distal of the canine through the mesial of the second molar, with the contacts of the premolars open. The film should be placed as far into the patient's mouth as his or her anatomy will allow.  The mandibular premolar film generally includes a complete view of the mandibular first molar as well.  The trick to taking the premolar shot is to position the film as far anteriorly as the curvature of the mandible will allow.

For the mandibular molars, the film is placed in the holder with a horizontal orientation. The second molar is centered on the film with the central beam perpendicular to the film. The contacts between the molars should be open and the distal of the third molar region should be visible even if there is no tooth present. Be careful about the placement of this film because the sharp edge can be uncomfortable in the sensitive floor of the mouth. If the patient is instructed to gently close rather than "bite" the film holder will be more secure and more comfortable.

Dealing with the tongue

There are two keys to placing the film painlessly in mandibular molar and premolar area.  The first is to explain to the patient that there really is enough room provided he/she relaxes the tongue.  Nervous patients frequently raise the tongue which causes the mylohyoid muscle to contract.  The floor of the mouth rises along with the mylohyoid muscle causing pain as the film is placed.  Once the patient relaxes the tongue, the amount of room increases dramatically.    The second key to placing the film painlessly is to angle the film to the lingual, medially toward the tongue itself.  This places the edge of the film well away from the area where the mylohyoid muscle attaches to the lingual aspect of the mandible.  Once the film is placed to its most inferior position using this technique, it is an easy matter to push the dorsum of the tongue out of the way to bring the film approximately parallel to the tooth.  The mylohyoid muscle slopes inferiorly as it approaches the midline, and when the inferior border of the film is placed in this position, it is less likely to encounter strong resistance. 

Of course, not every patient can be persuaded to relax the tongue, and it is not always possible to extend the inferior border of the film so that it falls below the apices of the teeth.  In cases like this, it becomes necessary to place the film at a steep angle leaving the inferior border of the film angled far lingually to the top of the film.  In these cases, aiming the beam from a low angle will  shift the shadow up so that the apex will appear on the film.  This is done at the expense of foreshortening the tooth.

 

The Panoramic Film (Panorex)

The panoramic film is a large, single x-ray film that shows the entire bony structure of the teeth and face.   It takes in a much wider area than any intra oral film showing structures outside of their range including the sinuses, and the temperomandibular Joints.  It shows many pathological structures such as bony tumors and cysts, as well as the position of the wisdom teeth. They are quick and easy to take, and cost a little more than a full series of intraoral films.   In addition to medical and dental uses, panoramic films are especially good for forensic (legal) purposes in the identification of otherwise unrecognizable bodies after plane crashes or other mishaps.

The main disadvantage to the routine use of panoramic oral surveys is the lower resolution of the shadowed structures.  Properly exposed intraoral films are always crisp and sharp while panoramic films show slightly fuzzy outlines.  They are, therefore, not especially good at diagnosing caries, and for this reason, most first visits that include a panoramic film also include a set of bitewing films as well.  In the event of a severe gagger, however, a panoramic film may prove adequate by itself.

Panoramic films differ from the others in that they are entirely extraoral, which means that the film remains outside of the mouth while the machine shoots the beam through other structures from the outside.  It fits into a broad category of medical x-rays called tomographs.  A tomograph is a computer assisted  method of focusing x-rays on a particular slice of tissue and showing that slice on the film as if there were no other structures outside of that slice.   It has a number of real advantages over the intraoral variety of film.  Since it is entirely extraoral, it works quite well for gaggers who could not otherwise tolerate the placement of films inside their mouths.  The patient stands in front of the machine (pictured on the right), and the x-ray tube swivels around behind his head.  Another advantage of the panoramic film is that it takes very little radiation to expose it.  The amount of radiation needed to expose a panoramic x-ray film is about the same as the radiation needed to expose two intraoral films (periapical or bitewing).  The reason for this is that the film cassette contains an intensifying screen which fluoresces upon exposure to x-rays and exposes the film with visible light as well as x-rays.