The New Zealand Dental Services
A high standard of oral health was maintained for all men by systematic examination by units. The average airman was made ‘dentally fit’ three times during his twelve months' tour of duty: once before leaving New Zealand and twice by the Mobile Dental Section. It was very rare, therefore, to find extensive caries and few extractions were necessary. The health of the gingival tissues was good, and although there was a marked prevalence of salivary calculus, as was noted in other tropical stations, the tissues soon regained their tone when the calculus was removed. The few cases of Vincent's infection were all recent arrivals from New Zealand. Major Cunningham reported on 15 March 1945 as follows:
It is considered that the good health of the soft tissues is due in no small measure to the large quantities of citrus fruit juices and the vitamin concentrates B1 and C which the men were encouraged to take each day. All the dental officers consider that the gingival tissues are healthier here than in New Zealand and the increased amount of vitamins B1 and C must be given some of the credit.
This opinion was endorsed almost word for word by Lieutenant-Colonel Simmers in a report dated 31 July 1945.
While giving due credit to this diet, it is felt that the strongest emphasis should be placed on the necessity for constant vigilance against the mechanical irritation of salivary and seruminal calculus, the main etiological factors in periodontal disease. It is significant that in the Middle East, where the supply of citrus fruits was page 361 negligible, there were no cases of Vincent's infection. Admittedly vitamins B1 and C were available in tabloid form but there is little evidence that they were regularly taken. The Dental Corps in the Pacific can take much of the credit for the general healthy state of the gingival tissues because of its declared war against calculus in any form. This is shown by the number of scalings carried out.
From March 1944 to March 1945, 11,530 patients were treated, and of this number 2134 were scalings. From March 1945 to the end of July of that year 6641 were treated, of which 1085 were scalings—that is, about 18 per cent and 16 per cent respectively. When it is remembered that the number of denture wearers was high in the New Zealand Forces and that these men would not need this treatment, the percentage would be nearer 30.
Fillings required per man were between 0.7 and 0.9 and extractions were never above 0.06 per man. The bulk of the denture work was remodelling and repairing, although a certain number of new full and partial dentures were made. From this it can be seen that most of the work was maintenance, with oral prophylaxis demanding much of the dental officer's time. In the United Kingdom there is a scheme whereby women are given some months' training in the purely mechanical operation of tooth scaling, and after satisfying a board of examiners that they have the requisite manual dexterity, are registered as dental hygienists with the right to perform this work. During the war the dental service in the Royal Air Force used dental hygienists and it would appear that there could be a considerable saving in trained manpower if similar use were made of them in the New Zealand Dental Corps. As the law stands in New Zealand there would have to be alterations before anyone other than a fully qualified, registered dental surgeon could carry out this work. For the protection of the public it would be essential to define very clearly the exact nature of the work to be sanctioned, especially in view of a popular misconception that the construction of artificial dentures is also a purely mechanical procedure. It cannot be too strongly stated that the two operations are not analogous and that the inclusion of the dental hygienist in a strictly limited capacity bears no relation to the claims of the dental mechanic to the right to carry out work for which he has not had adequate training.
One interesting problem arose in connection with the Air Force in the war which was new to the dental profession. Under certain conditions of pressure and strain, met with in high flying and divebombing, cases of acute toothache developed. On examination it was often difficult to find any reason for this as the tooth in question appeared to be sound, although it was found that it only page 362 occurred in teeth that had been filled. It appeared, therefore, that what was, under normal conditions, a sound filling needed something else to withstand the abnormal conditions to which aircrew were subjected. In most cases if the filling was taken out and reinserted with a greater pulp protection there was no further trouble. Research by Beryl Ritchey, Balint Orban, Warren Harvey and others led to the conclusion that disturbance of circulation at high altitudes caused pain in certain vital pulps which had previously been the subject of tissue changes. In many cases a lining of Eugenol mixed with zinc oxide was sufficient to protect the pulp, and this was used in the case of most deep cavities for men who were likely to meet the abnormal conditions. For convenience of discussion the subject was called Aerodontia.
The men were quartered and rationed by the Americans and were eating food to which they were not accustomed, and which was perforce under the existing conditions lacking in full vitamin content. This may have been the cause of some of the post-extraction haemorrhages noted by Major Washbourn. That at least was his opinion, and he went so far as to adopt preoperative medication as a routine, although no mention can be found of this being done by other dental officers in the Group.
When it came to making appointments for treatment there were certain important factors to be considered. The average patient in the Air Force was not trained to the same degree of physical hardness as his counterpart in the Army and was often living under a great strain. He could be compared to the University student at examination time, a young man with taut nerves. He was therefore not the best subject for dental operations and responded best to short appointments. Some men were highly trained personnel whose time was exceptionally valuable, so it was essential that they be absent from their duties as little as possible. It was usually possible for the dental officer to make his appointments in such a way as to avoid interfering with the duties of any individual, yet still have a full book, by calling on men from the less specialised units. Fortunately unit commanders were well aware of the importance of dental health and were fully co-operative.