A Cyst in No Man’s Land

Complete Radiographic Examination Necessary Area Posterior to Third Molar Often Overlooked “A CYST IN NO MAN’S LAND”

By Victor W. Dedon D.D.S.

                Why no man’s land? The area between the lower third molar and the angle of the jaw is very often forgotten when dentists are examining the teeth and jaws. The physician refers a patient to the dentist and expects him to report thoroughly on the condition of the mouth. The dentist examines the teeth, rays them, and reports no pathology, whereas there is often a hidden cause for the patient’s suffering. The patient continues to suffer and is juggled back and forth.

A case of this kind came to me in 1926.

PATIENT: Male, age 45.

HISTORY: For about three months the patient had been under his local physician’s care, being treated for a swelling of the left knee, headaches, fatigue, pain in the arms and shoulders. His tonsils and appendix were removed without relief. The physician referred him to his dentist who x-rayed his teeth and reported no pathology. The physician insisted that an infection was coming from the mouth. The patient walked with the aid of a crutch and cane. Left knee was very swollen. Patient stated that it seemed as though the knee wanted to work both ways, back and forth like a hinge.

EXAMINATION: After viewing the x-rays of his teeth, testing the pulps and finding them all vital, also transilluminating the sine, and finding it clear. I remarked “well, so far your dentist is correct, but your physician may be correct also.” The patient said, “how do you get that way?” and I replied “ I will answer that when I have two lateral jaw pictures.”

DIAGNOSIS: In raying the jaws I discovered a cyst on the left side, about the size of a quarter in circumference, see Figure 1. Notice the location of the cyst back of the third molar area and pressing directly on the mandibular nerve and artery. I could now answer the patient in behalf of the physician.

SURGICAL TREATMENT: A cyst the size of a large marble was removed and found to be pressing on the mandibular nerve and artery. The removal had to be done carefully so as not to injure the nerve of artery, both were in plain view after the cyst membrane was removed. The wound was sutured.

Now things began to happen. When the patient got out of the chair he remarked “why, that knee feels better already.” I warned him that if he got results in three months he should be happy. I saw him three days later he reported and he had laid away his crutch. Three weeks later he reported, feeling fine, no headaches, no fatigue, shoulder pains and the swelling of the knee was about entirely gone. Was it nerve pressure or infection or both?

Anyway, that is the story—now why not make a few lateral jaw pictures to give the patient the benefit of a thorough examination? All the equipment that is needed is a few 5×7 films, a set of intensifying screens (five by sevens will do) and a cassette.

The technique I use, is one explained by Dr. Clarence Simpson, in his book “The Technic of Oral Radiography.” It is as follows:

Technic for LateralJaw Examination

POSITION OF HEAD: Reclined to the limit of flexibility. Sagittal or median plane vertical. Check in contact with cassette or film container. For the condyle, face turned very slightly toward the cassette. For the cuspid and bicuspid regions, now in contact with cassette. For incisor regions, head inclined backward and  laterally to the limit of flexibility, with the nose and chin pressed tightly against the cassette. See figure 2.

ANTEROPOSTTERIOR ANGLE OF PROJECTION: Perpendicular to the cassette.

VERTICO-HORIZONTAL ANGLE OF PROJECTION:  Twenty-five degrees below horizontal.

PLACEMENT OF CASSETTE: With the arm of the operating chair removed, the patient is directed to turn until the region to be examined is toward the headrest. The cassette is rested against the headrest and inclined ten degrees toward the neck from vertical.

RETENTION OF CASSETTE: Supported by patient’s shoulder and hand for lateral regions, and both hands for incisor regions. Immobility promoted by a tight bandage around patient’s head, cassette and headrest.

CONE: Centered at the center of the region to be examined.

SPARK GAP: 4 ½ TO inches, or 66 to 72 kilo volts.

EXPOSURE: Cuspid and posterior regions 40 to 60 milliampere seconds at a 40 inch target film distance with double coated films and intensifying screens. 200 to 250 milliampere seconds without screens. Incisor regions 100 to 150 milliampere seconds, and impracticable at this distance without screens.

Lowry Medical Arts Bldg.,
St. Paul. Minn.