As a multispecialty domain, implant dentistry involves competency in oral surgery, periodontics, restorative dentistry, and prosthodontics. Thus, classifying implant dentistry as a subspecialty of any existing formal dental specialty is difficult [18, 19]. The resulting multiplicity of professional stakeholders, along with the perceived high commercial value, may have together contributed to a rather unregulated surge in actual implant practice that has far outpaced formal university-based training [20]. Professional societies have attempted to establish postgraduate curricula, but the relative lack of university-based training has often been largely substituted by informal, short-term, unstructured, and industry-initiated educational opportunities [21]. The educational value of these industrial promotional events often remains questionable because implant dentistry is mostly reduced to a mechanistic procedure that can be simply handled if the right system is used. To manage this threat, some expert committees have recommended that basic aspects (i.e., healing and tissue integration, biomechanical and material principles, and prosthetic and surgical skills and procedures) should be a formal part of the undergraduate curriculum [4,5,6, 12, 15]. Whether this should also include competency in implant surgery remains a matter of debate [7]. The findings of our study confirm that the attitudes concerning the importance of implant dentistry for dental students vary widely and may depend on the level of clinical experience in implant dentistry and the vested interest in the provision of undergraduate dental education.
Group assignment
Participants were assigned into three groups (i.e., novice, educator, and dentist), based on their level of educational and clinical experience. The rationale for this assignment was to present the different viewpoints of the targeted learners, providers of undergraduate education, and experienced dentists. University educators would logically be expected to provide the best insight into the possibilities and limitations of dental education. University educators are highly cognizant of these issues and thus make efforts to design curricula with the goal of ensuring that students acquire the requisite basic clinical skills for the core dental disciplines. However, this task is complicated by the fact that undergraduates treat different patients with a wide range of oral problems that require treatment with varying levels of difficulty. However, they are expected to have acquired a standardized knowledge base and a set of practical skills before graduation [13]. Thus, even without taking into consideration the discipline of implant dentistry, the organization and supervision of traditional undergraduate practical treatment courses remain a significant challenge, and university educators are often resistant to proposed changes and innovations. To account for this in our survey, the dentist group was split into educators and dentists working in universities, and dentists working in private practices. The dentist group had the highest proportion of participants with an enhanced level of implantation experience (> 500 implantations performed).
Theoretical knowledge
A consensus existed between the three groups regarding the teaching of theoretical knowledge and skills. This consensus is in accordance with recommendations from the literature for sound knowledge in clinical information gathering, diagnosis and treatment planning, establishing and maintaining oral health, surgical procedures, periodontal management, restorative and prosthodontic management, and health promotion [5, 11, 16]. The requirement for educational program supervision by an experienced specialist in prosthodontics has been emphasized and is current practice in some dental schools in North America [18, 19]. This is in line with the requirements of a synoptic treatment concept, with implants being one component of comprehensive rehabilitation.
Implant planning by undergraduates
One question was whether implant planning should be a part of undergraduate dental education. In general, this proposition was supported by most participants in each group.
With regard to the preferred implant planning methods, novices and educators favored the use of cone beam computed tomography (CBCT). However, dentists in private practices preferred conventional implant planning by using standard radiographs (i.e., panoramic and periapical radiographs), and the fabrication of an analog drilling template in the undergraduate curriculum. The disagreement reflects the current debate on the differing guidelines concerning the necessity of CBCTs for implant planning [22]. The guidelines’ divergence was interpreted as an influential factor for health professionals to ignore these recommendations. To date, German dentists have no current guidelines. The CBCT recommendation regarding implant planning from 2013 has been under revision since 2018.
In general, the preparation of clinical materials in the laboratory (e.g., the fabrication of drill templates) and clinical implant planning received very positive feedback from the undergraduate students, and these activities had a positive influence on the graduates’ future plans to perform implant therapy [4, 23, 24]. However, Fortes et al. [25] reported that implant planning by novice and experienced dentists differed if standard radiographs were used instead of CBCT images. This finding may be because of the fact that, compared to conventional planning methods, modern planning software anticipates several planning steps in advance and is able to provide a higher level of safeguards for a novice. Thus, based on these considerations and the limited amount of available time in undergraduate dental curricula, implant planning using CBCT may be suitable in undergraduate education.
Implantation by undergraduates
Implantation by undergraduates was not supported by 57.1% of educators and 52.5% of dentists. By contrast, most (89.5%) undergraduate students supported the teaching of this procedure. The educator group interestingly had the greatest proportion of critics. This finding may be because of the fact that implantation by undergraduates requires direct supervision by an experienced instructor and a wide range of tools, which are often expensive. An experienced clinician is also required for screening and selecting suitable patients. Moreover, educators may be tasked to teach in areas of the curriculum and to supervise clinical procedures in which they have limited experience [13, 24, 26].
The results of previous studies [27] have shown that implantation using CBCT-based digitally fabricated drilling templates achieves good results that are independent of an operator’s experience. Thus, from a scientific point of view, this method may be suitable, even for novices. In addition, patients prefer the comfort of computer-guided flapless surgery and positively evaluate implantation performed by undergraduates [28,29,30]. However, experienced surgeons often criticize that less experience, in combination with an enhanced sense of safety, leads to a lack of awareness regarding potential intraoperative complications and a false sense of security on the part of the student [1]. This risk may be countered by undergraduate students’ management of more complex and demanding implant treatments in university hospital out-patient departments. The clinical results of different implant educational programs implemented at different universities worldwide are acceptable and have success rates ranging from 92.2 to 98.8%, using different implantation techniques (e.g., drilling and orientation templates) [15, 28, 31,32,33,34]. This outcome is comparable with that of other studies in which surgeries were performed by experienced surgeons [35, 36], and suggests that undergraduate students are capable of performing basic implant surgery under supervision, provided that straightforward cases are assigned to them and thorough preclinical training is provided beforehand. Thus, these results provide support for the integration of implantation into the undergraduate curriculum.
Bone augmentation by undergraduates
Educators, dentists, and one-third of the novices did not support the integration of bone augmentation into the undergraduate curriculum. This assessment of augmentative measures as a domain of postgraduate training and specialist management is in accordance with recommendations reported in the literature [11, 26]. In most studies reporting undergraduate implant curricula, the necessity for bone augmentation has been described as an exclusion criterion [28, 31, 32].
Implant restorative treatment by undergraduates
A consensus existed regarding the question of whether undergraduates should perform implant restorations. Novices appreciated the opportunity to perform a diverse range of restorations, including those in the esthetically demanding anterior region, whereas experienced dentists disapproved of undergraduates performing complex treatments. De Bruyn et al. [7] evaluated undergraduate dental implant programs in Europe and found that only 44% of programs permitted undergraduate students to perform prosthetic restorations by using implants. These procedures were primarily limited to single crowns on molars (28%) or bicuspids (33%), and only 16% of cases involved implants in the esthetic zone [7]. Between 9% and 23% of cases involved mandibular overdentures retained by two implants. These findings are consistent with the results of American and Canadian surveys [13, 18, 19]. Most experts agreed that only straightforward restorative or prosthetic procedures should be a part of an undergraduate curriculum [11, 13], thus correlating with the attitudes of the dentists participating in our study. The fact must also be acknowledged that the enthusiasm demonstrated by undergraduate students, in combination with their lack of experience, may often result in their underestimation of the difficulty and complexity of cases requiring implant therapy and the need for specialist referral.
Postoperative care provided by undergraduates
With regard to postoperative care, no relevant differences existed between the attitudes of novices, educators, and dentists. This finding is in agreement with previous recommendations, which have stressed the importance of knowledge and skills in aftercare measures in the undergraduate curriculum [11, 13]. With regard to the aging demographic profile in Germany and worldwide, and the recent surge in implant treatments, it seems reasonable to train undergraduates in postoperative care and long-term maintenance, as they will be confronted with this task immediately after graduation [2, 3].
Practical surgical prerequisites before the first implantation
In contrast to the novices, the dentists and educators emphasized the need for advanced surgical skills and clinical experience (i.e., increased number of tooth extractions, operative removal of third molars, apicoectomy, preprosthetic soft tissue surgery) before performing the first implant insertion. This finding supports that of a previous international study that formulated the assumption that, on account of a lack of experience regarding surgical or implant complications and demands, graduates do not interpret surgical results in the same manner as more experienced dentists [1]. Deficiencies in the ability to discriminate normal healing and anatomical structures from pathology may lead to a novice’s failure to detect less-than-ideal treatment outcomes.
Of note, educators did not rate surgical skills as highly as dentists did. One explanation may be that enhanced surgical skills training in undergraduate education is simply impractical for the predetermined time provided. However, the demand for enhanced practical skills were correlated with the implantation experience of the participants. Dentists working in private practices constituted one-half of the survey participants and more than one-fifth of the participants were highly experienced in implant therapy (i.e., they had inserted more than 500 implants over the course of their career). This factor may have influenced the results.
Practical prosthetic prerequisites before first implantation
Compared to dentists, the novices and educators interestingly evaluated assisting during implant prosthetic treatment and experience with crown impressions before performing the first implant treatment as more important. This finding may be because conventional prosthodontics has had an increasingly important role in recent decades in the German undergraduate dental curriculum and because crown impression-taking has routinely been emphasized from the first practical phantom courses up to the final examinations [37]. As the performance of crown impressions differs from that of implant impressions, the former procedure may not necessarily be seen as a prerequisite for the latter procedure. In a crown impression, the gingival margins have to be compressed to prevent gingival fluids/blood from spilling out of the gingival sulcus over the preparation margin; an implant impression requires the correct placement of the correct impression post. By contrast, an agreement was found between educators and dentists regarding the necessity for undergraduates to have obtained experiences in the fabrication of tooth-supported fixed and removable dentures before they started to fabricate implant restorations.
Several recommendations exist in the literature regarding surgical and prosthetic simulation procedures that should be performed on phantom heads or artificial jaws. However, to the best of our knowledge, no recommendations exist pertaining to the types of conventional dentures that undergraduate students should provide to patients as a prerequisite, before starting their first implant cases. On account that educators and dentists considered this aspect as important, previous experience with specific conventional denture treatment during the planning of future dental (implant) curricula seems reasonable to consider. In the early years, when implant dentistry was mainly applied on edentulous patients, this was accepted as a prerequisite.
Prioritization of teaching content
Both educators and dentists considered implantation performed by undergraduates much less important than teaching basic theoretical knowledge, postoperative care and maintenance, and the prosthetic restoration of implants. This finding is supported by the recommendations of previous studies that have advocated the need for solid theoretical foundations and the restoration of simple “straightforward” cases, based on the Simple, Advanced, Complex (SAC) classification, which has been ascribed a higher priority than the implantation itself [6, 13].
However, it has to be emphasized that when the daily practices of graduates from a dental school with and without extensive implant education (laboratory and clinical experience in implant placement and restoration) are compared, graduates who had clinical implant experience during their undergraduate education were found to have performed twice as many implant restorations in their practice; placed more dental implants; referred more patients for specialized surgery; and participated more often in continuing education in implant dentistry [38]. The objective of health sciences education is to deliver rote knowledge to students and to prepare them to overcome new challenges and clinical problems over the course of their careers as dentists. Therefore, we recommend that a solid foundation in implant dentistry be fully integrated as a minimal standard within an undergraduate dental curriculum in countries with the appropriate resources [39].
Limitations of the study
The current study has several limitations. It was based on an anonymized online survey. Thus, the participants’ answers could not be independently verified. In the study cohort, the number of educators was smaller than that of dentists and novices. In addition, the survey questions pertaining to teaching content only took into consideration the overarching issues, based on the recommendations of the 2008 Prague Consensus Conference on Implant Dentistry [5]. Future studies are necessary to define precise learning objectives. Moreover, undergraduates generally experience stress related to difficulties in meeting procedural clinical requirements; therefore, additional studies are required to evaluate which teaching and learning components within existing curricula can be reduced or replaced with implant dentistry teaching content [40]. Finally, the transferability of our study’s results may depend on the financial resources countries have in order to implement implant curricula into the dental curriculum. Especially in developing countries, many impediments such as the lack of financial resources, lack of qualified faculty, or inadequate curriculum time make implementing implant dentistry in undergraduate curriculum difficult [41].
