Part I. Levels of Activity and Experience in Oral Implantology
M.P. J. Young
, D.H. Carter
, BSc, MPhil, PhD
, P. Sloan
, BDS, PhD, FRCPath, FDS RCS (Eng)
, A.A. Quayle
, LDS, FDSRCS (Eng), PhD
Units of Oral Surgery and Oral Pathology, Turner Dental School and Hospital, University of Manchester, United Kingdom.
The benefit of endosseous dental implants has been demonstrated in fully edentate and partially dentate patients. As a consequence, their use has markedly increased, and clinicians are now seeking to increase their academic knowledge and skills in a discipline that is relatively new to many clinicians in the UK. The Association of Dental Implantology (UK) was formed in 1986 and is a charitable organization for the public and the profession; its aim is to increase awareness of implant reconstructive dentistry (M. Norton, Chairman of the Association of Dental Implantology (UK). Personal communication. December, 1999). Since its inception in 1986, the ADI has organized more than 150 lectures, 130 study club meetings, and 12 major symposia at which national and international speakers from numerous disciplines have presented lectures on subjects based on, or related to, oral implantology. This survey set out to establish the levels of experience of the clinical members of the ADI in terms of the range of surgery and the number of implants inserted as well as to determine the locations for these activities and the qualifications possessed by these members of the ADI. MATERIAL AND METHODS.
Before this survey, the questionnaire was piloted by 10 dentists who were experienced in oral implantology (at present there is no recognized specialty in oral implantology in the UK). After this pilot study, the questionnaires were posted to current members of the ADI registered as clinical members in 1998 with the individual results anonymized. The data were collected between July 1998 and May 1999. This survey did not include active implant clinicians in the UK who were not members of the ADI. A total of 273 replies were returned from 408 posted questionnaires to give a 66.9 response rate.3 RESULTS.
Recruitment Rates of Active Oral Implantologists and Clinical Activity.
The trend in clinical activity was determined by asking members the year in which they commenced clinical work in implant dentistry. Of the 184 clinicians who indicated that they were active in some aspects of the surgical phases of implant dentistry, 161 respondents provided complete details of their implant experience. Clinical activity in oral implantology is increasing. The earliest recorded clinical activity was in 1969, and activity showed a slow rate of growth to 1984 (from 5–20 clinicians). During the following decade, there was a rapid increase in the number of active clinicians (from 33–217). In contrast, there has been an apparent decrease in the rate of recruitment of active clinicians in recent years (1995 to date). Levels of Surgery Performed Surgical activity was divided into arbitrary categories (see below) and the participants were asked to identify their main area of surgical activity (Fig. 3). Arbitrary Bands of Surgical Activity.
- All surgical aspects (including major grafting under general anaesthesia)
- Implant surgery 1 intraoral bone block harvesting (eg, chin and lateral ramus)
- Implant surgery 1 augmentations (excluding intraoral bone block harvesting)
- Implant surgery only
- Surgical and restorative aspects, excluding major grafting
- Implant exposure and restorative phase
The majority of the respondents were actively practicing in implant dentistry with only a small proportion of this sample clinically inactive (9.2%). Equally, only a small percentage (11%) was involved in all the surgical aspects including major bone grafting techniques. Levels of Experience: Implants Inserted.
To quantify the levels of experience in implant surgery, participants were asked to indicate the approximate total number of implants they had personally inserted at the time of the survey. Approximately one third of respondents had inserted between 100 and 499 implants (over their total period of activity in implant dentistry), whereas only seven members (4.3%) had inserted more than 2000 implants. Professional Qualifications.
Survey participants were asked to provide details of their qualifications; 245 clinicians responded. The majority of the sample (56.3%) possessed at least one quali fication in addition to their basic dental degree. Twenty-three had been awarded academic qualifications leading to a postgraduate degree, with seven of these being based on oral implantology. Fifty-six had diplomas from the Faculty of General Dental Practitioners, whereas 35 had diplomas from the Royal Colleges of the UK and Ireland. Only nine respondents possess a registered medical qualification, and eight had diplomas from the International Congress of Oral Implantology (USA). When considered as a whole, only 15 members had undergone recognized training that was specifically based on oral implantology. Principal Work Place of Survey Participants Who Are Active in Clinical Implantology.
Respondents were asked to indicate the main location of their clinical activity in oral implantology (Table 3). Nearly equal proportions of general dental practitioners performed clinical implantology based in private and National Health Service dental practices (24.2% and 26.1%, respectively). With regard to specialist practice, the bulk of the clinical activity by this sample occurred in restorative-based practices. In contrast, the majority of those who practiced in a teaching hospital environment were doing so within the specialty of oral and maxillofacial surgery. Only five (2.1%) respondents worked in implantdedicated units. DISCUSSION.
There has been an increase in activity in oral implantology in several countries, notably the United States and Sweden. In contrast, relatively low levels of activity have been reported in the UK. High rates of success were attributed to endosseous dental implants in 1981, and a significant increase in clinical activ ity followed in this sample in the period between 1985 and 1995. From these data, an initial time lag is apparent during which it might be presumed that clinicians in the UK were training in this discipline. In contrast, there was a fall in the rate of recruitment of new clinical members from 1996 to 1998. Although the reasons for this are unclear, contributory factors might be “market saturation” and the increasing awareness of general practitioners in the UK of the need for appropriate referral when they feel that treatment is beyond their competence. Alternatively, the fall in the rate of recruitment may reflect a growing concern over the success rates of implants. Early studies reported success rates greater than 90% for endosseous dental implants in “centers of excellence” where stringent criteria were imposed. However, more recent studies have reported lower success rates even though less stringent criteria for success were used. Equally, the implant system used might be a critical factor in the success rates achieved because it has been claimed that only one implant system possesses appropriate long-term data. Another factor affecting recruitment to oral implantology might be the nature of the clinical training that potential members already possess. Respondents Who Perform Some Aspects of Implant Surgery.
The majority of respondents performed at least some of the surgical phases of implant dentistry. The range of surgery performed varied from implant exposure to major bone grafting, and presumably this reflects the variation in training and qualifications possessed. Concerning experience of inserted implants, there was a wide variation. Although approximately one third of respondents had inserted between 100 and 499 implants, a large proportion had inserted fewer implants (1–99). It is acknowledged that success rates are likely to improve with experience, and operators with low rates of clinical activity might take longer to achieve optimal success rates. On the other hand, in the absence of any quantifiable success rates for the implants inserted and reported in these data, the relatively low levels of experience of certain groups might simply reflect more stringent patient selection. The situation is, moreover, compounded by the fact that oral implantology is carried out in the UK by a variety of clinicians including general dental practitioners, restorative dentists, periodontists, oral surgeons, and oral and maxillofacial surgeons. The techniques used in clinical practice will depend somewhat on the training pathway and experience of the clinician, and this might influence implant success rates. For example, oral and maxillofacial surgeons might use, or recommend, autogenous bone grafts in the “staged” bone augmentation technique because it is a procedure often encountered during their clinical training and day-to-day duties. In contrast, general dental practitioners might be more likely to use collected bone debris and/or allogenic and alloplastic materials for the staged bone augmentation technique. Qualifications Possessed by This Sample of the Clinical Members of the ADI.
Increased importance is being placed on both formal and informal postgraduate education in the UK. The majority of respondents possessed additional qualifications, and the type of additional qualification varied widely. It is quite striking that the number of respondents who possessed academic qualifications in oral implantology was low (2.6%). This could be explained by the limited availability of academic training in oral implantology in the university dental schools and hospitals of the UK and Ireland. With increasing use of endosseous implants reported, the demand for academic and clinical training at university institutions should increase. The availability of such training can be expected to affect the quantity and quality of implant research in the UK. In the absence of widely available universitybased implantology training, general practitioners are likely to gain their implantology knowledge and skills in other sectors. (Additional data from this survey revealed that greater than one third of this sample of ADI members contribute to implantology teaching in private institutions.)
This survey could only estimate the total number of implants inserted by members of the ADI within the UK (between 51,000 and 93,000), and the success rates achieved could not be determined. For practicebased research, clinical registries have provided an important source of data. The ADI is well positioned to establish such a registry within the UK. For the location of clinical activity, this occurs in a wide range of locations, although the number of implant-dedicated clinics was low. Increased academic training opportunities in this clinical discipline and recognition of oral implantology as a specialty might cause the numbers of dedicated implant units to increase.REFERENCES.
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