Article Type : Research Article
Authors : Sikri A, Sikri J, Sharma A, Bagaria A, Prakash Bumb P and Gupta R
Keywords : Dental; Dentistry; Digital; CBCT; Scanners; Design; Milling; Machining; CAD; CAM; RP; Dental implants; Implantology; Nuances
The
incorporation of digital techniques and innovations is not a very new chapter
in the field of dentistry. Since the inception of digitization in dentistry
particularly dental implantology, there have been significant updates and
contributions [1]. This has led to the attraction of dental surgeons,
academicians as well as dental students to plunge into the practice of digital
implant dentistry. The use of CAD CAM in dentistry dates to the 1980s when Dr.
Francois Duret, did extensive research in the field of optical impressions.
This was followed by Preston in 1990s, Mörmann et al. in 1989; and Andersson et al.,
in 1996 who did extreme research in the field of digital dentistry as pioneers
[2].
Earlier,
the dental applications pertaining to the digital technology was limited only
to inlays and onlays. Subsequently, with the inclusion of more novel and recent
innovations, the digitization came out truly to be a promising innovation in
implantology. The incorporation of digital techniques into implantology helped
the dental surgeons to implement a novel approach in the field of dentistry.
Out of this, dental implant placement i.e., both the surgical and the
prosthetic protocols fascinated the clinicians to a greater extent [3].
Previously,
the conventional 2D approaches had been used to acquire the diagnostic data of
the patient. The practitioners had been using free hand drilling as a blind
procedure to rehabilitate the patients with dental implants. Subsequently, with
the inclusion of digital approaches, the angulation and placement of the dental
implants along with proper planning has been achievable. Proper implant
placement is important for the overall health of the oral tissues. The
combination of modern digital approaches including CBCT, digital scanners, 3D
designs as well as the printed techniques have helped the clinicians as well as
the laboratory personnel to successful rehabilitate the implant patient with
predictable outcomes [4].
Tooth
loss is one of the most common causes for patient handicap. This can occur due
to caries and periodontal disease commonly with other factors involved less
commonly. The prosthetic rehabilitation of such patients can help to revive
them from this handicap. Talking in these terms, the 3rd dentition
i.e. dental implants have always been the top most preference for dental
clinicians for prosthetic rehabilitation. Moreover, it is also the 1st
choice of treatment as far as the patients are concerned, keeping in view the
increased awareness, better treatment protocols and increased life expectancy.
This has led to the emerging discipline of dental implantology outshining the
other treatment protocols i.e. removable and fixed prosthodontics. The
incorporation of dental implants has totally change the OHrQol (Overall Health
related Quality of life) [5].
The
concept of digital dentistry had always led to the revolution in the field of
dentistry. The inclusion of digital dentistry admixed with the field of dental
implantology has given birth to the concept of digital implant dentistry or
digital implantology [6]. Digital dental implantology revolves around 3 major
components namely scanning, designing, and milling. A stepwise approach
commonly used in the field of dental implantology is termed as digital
workflow. This can be elaborated as a workflow in which every phase of the
diagnosis, planning & treatment is conducted by a digital resource (Figure
1).
The
digital workflows are commonly categorized as analogy, partial digital and
complete digital workflow (Figure 2). As stated, the digital workflows
incorporated in the field of implant dentistry has improved the predictability
as well as the treatment outcomes [7]. The stepwise approach of digital
workflows is a tabulated format that should be followed during prosthetic
rehabilitation of the patient (Figure 3).
The
inclusion of digital diagnostic modalities i.e., 3D CBCT (Cone Beam Computed
Tomography) has been a benchmark in the field of dental implantology.
Previously, CT (Computed Tomography) had been into medical practice, but with
the radiation exposures associated, its use in dentistry was discouraged.
Conversely, CBCT gave a better accuracy of the parameters of bone and
associated vital structures with reduced radiation dosages [8]. CBCT is now being
commonly used as the 1st choice of diagnostic modality while
rehabilitating patients with dental implants. CBCT as juxtaposed with MRI
(Magnetic Resonance Imaging) is quite commonly discussed in the literature. MRI
is a road beyond CBCT in terms of soft tissue imaging. Metal artefacts have
been a common limitation of CBCTs. CBCT with its broad horizon, has been into
picture for scanning the dental impressions as well as the models. However,
unfortunately, the surface texture details associated is still questionable
[9].
Figure 1: Digital workflow in dental implantology.
Figure 2: Types of digital workflow.
Scanners have revolutionized the digital implantology which can be credited to the incorporation of intraoral scanner (optical scanner) along with extraoral scanner (lab scanner). Recently, with the inclusion of facial scanner, the field of digital dentistry has done wonders. The accuracy and effectivity of the implant treatment has been significantly improved with the use of scanners. Scanners help to capture the oral cavity which further helps planning for the implant patient [10].
Figure 3: Digital workflow in implant dentistry – a stepwise approach.
Figure 4: Surgical Guides (Templates) – Applications.
Virtual implant planning or 3D planning gives an idea about the digital simulation of the planned restoration for achieving the treatment outcome more precisely. This is followed by the placement of dental implants under the effect of digital implantology with more precision and safety [11]. Precise dental implant placement can be made possible with the use of Surgical Guides or templates which are designed and machined/milled/printed ultimately. A commonly used term in the field of dental implantology is “Go Guided” which showcases the effectivity of surgical guides for further improving the accuracy and placement of the dental implants (Figure 4). The surgical guides have been quite effective as far as the placement of basal and zygoma implants is concerned. Surgical guides can be static or dynamic. The dynamic ones have shown better treatment outcomes in contrast to the static surgical guide. This has led to better placement of the dental implant further improving the treatment outcome [12].
Figure 5: Dental implant scan body.
Figure 6: Conventional impressions - shortcomings/disadvantages.
After
placement of the healing abutment to mimic the shape of a natural tooth,
impressions of the associated area are taken with the help of scanners. This is
commonly known as an optical (digital) impression. The impressions for a single
implant generally pose no problem. However, for multiple implants and full
mouth rehabilitations, a combination of open mouth impression technique using
scannable elatomers along with lab/extraoral scanners, will help to achieve the
best possible results [13].
A
very important component of impression i.e., implant scan body i.e. a true
representation of the position and orientation of the respective dental
implant, analogy or abutment in CAD CAM scanning procedures, is generally used
during these impression procedures. It is commonly known as CAD CAM implant
impression coping (Figure 5). The digital impressions in implant dentistry have
successfully overcome the shortcomings associated with the conventional
impressions [14] (Figure 6). This is followed by the designing of the abutments
& final prosthesis with the help of CAD (Computer Aided Design) [15]
commonly known as the customized abutment for optimal form and tissue support.
The abutment & the final prosthesis if finally machined or milled with the
help of subtractive milling i.e., CAM (Computer Assisted Milling) [16]
or additive manufacturing i.e., RP (Rapid Prototyping) or Rapid Additive
Manufacturing. This is followed by the final placement of the implant supported
fixed restorations. Henceforth, the incorporation of the complete digital
workflow has totally changed the landscape of the dental implantology.
Dental
implants had been and will always remain as the 1st choice treatment
modality for the clinicians, a preference for getting treated by the patients,
a subject to research for the faculties and researchers in various universities
as well as a new and an innovative way of learning by the dental students and
young budding dental surgeons. There has been a paradigm shift from the
conventional dental implantology to the digital dental implantology in due
course of time. The ubiquitous tool of digitization into dental implantology
has been a magic rather a dream come true to rehabilitate the patients in the
best and the most natural way. Although, the learning curve is steep but still
the dental surgeons can learn with good knowledge and updates to become more
proficient in their own skills to treat the implant patients. The nuances of
digital dental implantology are significant not only in research but also in
day-to-day clinical practices to improve the accuracy, predictability, and
outcome of the dental implant treatment.