Retirement

Editor's note: Parts 2 and 3 of this series are published in the April and May 1991 issues of JCO.

The 1986 JCO Study of Orthodontic Diagnosis and Treatment Procedures was the first comprehensive nationwide survey of the methods and appliances used by orthodontists in everyday practice. The questionnaire for the current Study was a refinement of the previous one; several items that seemed to be unclear or unrevealing were dropped, and new questions were added to produce even more useful details.

The questionnaire was mailed in October 1990 to 8,901 practicing specialty orthodontists, which was believed to be virtually the entire population of such practitioners in the United States. There were 1,253 usable responses, for a response rate of 14%. The size of the response and the similarity of demographic data to those of the biennial JCO Orthodontic Practice Studies tend to confirm the validity of the results.

After the responses were entered on computer by an impartial third party, they were tabulated using the Statistical Package for the Social Sciences . The tables in this article show the percentages of the total respondents in each category ("total" meaning all who answered that section of the questionnaire). Tables shown in JCO are intended to present the highlights of the Study that would be of most interest to our readers, and do not represent the entirety of the data collected.

Medians are usually reported rather than means because medians are less influenced by extremely high or low responses. In some cases where the response was a percentage (as in percentage of extraction cases), the means were considered more useful because a large number of responses at 0 resulted in medians of 0.

When a question in this Study was the same as in 1986, results from both surveys are shown in the table. "NA" indicates that a particular item was not included in the 1986 questionnaire.

Demographics

The demographics of this sample were much the same as in 1986, except that the median percentage of adult cases increased from 20 to 25 (Table 1). In the previous Study, early-treatment cases amounted to 10% of the average practice; on the current questionnaire, this item was replaced by two-phase treatment, which accounted for 20% of the average practice.

The median age at which the respondents recommended starting treatment was 10. The median age of the youngest patient in the practice was 6; of the oldest patient, 59.

Brackets

Perhaps the most noteworthy technological change between the 1986 and 1990 studies is in the use of ceramic brackets (Table 6). Only 5.6% of the orthodontists in 1986 reported using them occasionally or routinely, but by 1990, 88.2% of the respondents used them "on a regular basis" (the difference in wording results from a change in the questionnaire).

As in 1986, nearly all the respondents used metal brackets. In the 1986 Study, 57.6% said they used plastic brackets occasionally and 2.6% routinely, while in 1990, 24.3% used them on a regular basis. Because of the change in wording, it would be difficult to draw a conclusion about trends in plastic bracket usage.

Archwires

The questionnaire section on orthodontic wires seemed to be confusing to respondents in 1986 and therefore was completely revised. In the current Study, 90.4% of the total sample reported using nickel titanium wires and other alloys (including cobalt alloys) on a regular basis (Table 7). Nearly the same number (89.7%) said they used stainless steel wires regularly, and 72.1% used multistranded stainless steel wires regularly.

Extractions

Only 88% of the respondents reported treating at least one extraction case--down from 95% in 1986--and extraction cases accounted for a considerably lower median percentage of patients in 1990 than in 1986 (Table 11). As in the previous Study, the most used combination of extractions was upper and lower bicuspids, although they accounted for a lower percentage of extraction cases. (Means were selected for the 1990 figures because in many categories, the large number of respondents answering "0" resulted in many of the medians being computed as 0.0.)

Use of third molar enucleation was virtually the same in 1990 as in 1986, while use of serial extractions increased slightly.

Finishing and Retention

Of the finishing procedures surveyed, use of incisal adjustment, stripping with power instruments, and fiberotomies referred to periodontists and general dentists increased slightly between 1986 and 1990 (Table 12). Stripping with handpieces was performed by substantially more respondents in 1990. Use of epoxy buildup, stripping with hand instruments, and fiberotomies by orthodontists declined.

As in the previous Study, the median duration of retention was 24 months (Table 13). However, choices of "indefinite" and "lifetime" were added to the 1990 questionnaire, and more than half the respondents selected one of these.

TMJ Treatment

The amount of TMJ treatment performed by orthodontists appeared to increase only slightly between 1986 and 1990--the percentage who reported treating at least one TMJ case in the preceding year rose from 70 to 75, and the median number of cases rose from 12.5 to 15.0 (Table 14).

More choices of diagnostic methods were listed on the 1990 questionnaire, and therefore it is difficult to measure trends. A patient history and muscle palpation were used by virtually all of the respondents, and mounted casts by a majority. Therapeutic diagnosis, transcranial x-rays, laminagrams, and magnetic resonance imaging were all used by at least one-fourth of the clinicians.

Most of the respondents attributed TMJ dysfunction to a combination of causes, with fewer respondents listing stress, occlusion, or muscle dysfunction as the chief cause. The order of responses was virtually the same as in 1986 although "combination of causes" was not included on the previous questionnaire.

Somewhat fewer patients than in 1986 reportedly had TMJ treatment in conjunction with orthodontic treatment, and lower median percentages were also referred for surgery or psychological evaluation. The median success rate (defined as "asymptomatic one year post-treatment") remained at 75%.

As in the previous Study, splints were the most commonly used method of TMJ treatment (Table 15). Other methods used at least occasionally by more than half the respondents included equilibration, palliative methods, physical therapy, fixed appliances, anti-inflammatory drugs, and muscle relaxants. Routine use of functional appliances and equilibration declined between 1986 and 1990; biofeedback and acupuncture were used by more respondents in 1990, and use of other methods listed in both surveys remained relatively unchanged.