FUNDAMENTAL
RESEARCH
Comparative Evaluation of the Internal
and Marginal Adaptations of CAD/CAM
Endocrowns and Crowns Fabricated from
Three Different Materials
Mahya Hasanzade, DDS, MS
Dental Research Center, Dentistry Research Institute and Department of Prosthodontics,
School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Majid Sahebi, DDS, MS
Simindokht Zarrati, DDS, MS
Department of Prosthodontics, Faculty of Dentistry, Tehran University of Medical Sciences,
Tehran, Iran.
Leila Payaminia, DDS, MS
Department of Prosthodontics, Faculty of Dentistry, Bushehr University of Medical Sciences,
Bushehr, Iran.
Marzieh Alikhasi, DDS, MS
Dental Research Center, Dental Implant Research Center, Dentistry Research Institute,
Department of Prosthodontics, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Purpose: To evaluate and compare the internal and marginal adaptations of chairside CAD/CAM (CEREC)
endocrowns and crowns fabricated from lithium disilicate glass-ceramic (IPS e.max CAD), zirconia-reinforced
lithium silicate glass-ceramic (VITA Suprinity), and hybrid ceramic (VITA Enamic). Materials and Methods:
Dental models of the two first maxillary molars were selected. One was prepared for an endocrown, and
the other for a standard all-ceramic crown. A total of 72 CAD/CAM restorations, including 36 endocrowns
and 36 crowns made of IPS e.max CAD, VITA Suprinity, and VITA Enamic (n = 12 each), were fabricated.
Discrepancies were measured in the buccal, mesial, lingual, and distal aspects of three sites (marginal, midaxial wall, and occlusal/floor) using the noncontact ATOS scanner. Statistical analysis was performed using
MANOVA and between-subject effects tests (α = .05). Results: Mesial axial wall discrepancy was significantly
lower in endocrowns compared to occlusal discrepancy in crowns, while distal axial wall discrepancy
was significantly higher. Moreover, floor discrepancy was found to be significantly lower in endocrowns
compared to occlusal discrepancy in crowns. However, type of material had no significant effect on any kind
of discrepancy. Conclusion: The marginal and internal adaptation values were within a clinically acceptable
range for both kinds of restoration and all three materials. However, restoration type (crown vs endocrown)
was significantly different in the mesial and distal axial wall and occlusal/floor discrepancies, regardless of
restoration material. Int J Prosthodont 2021;34:341–347. doi: 10.11607/ijp.6389
T
he functional and esthetic restoration of severely damaged endodontically treated teeth is still a clinical challenge.1 A typical protocol to restore these teeth is to
use posts and cores and a full-coverage crown. However, with the development
of adhesive dentistry, this goal is easily made feasible by an endocrown.2 An endocrown is a one-piece, post-free ceramic restoration that assemble the crown and the
pulpal cavity part in one component.3 In comparison to the classical post-and-core
approach, this modern alternative treatment modality offers several advantages, such
as more preservation of tooth structure, less need for sufficient interocclusal space,
reduced risk of root fracture, and possibility of retreatment in case of endodontic
failure. Moreover, both the number of appointments and the cost decrease, as there
is no need for the many technical steps for post cementation, core build up, and potential crown lengthening.4,5
A systematic review done by Wittneben et al6 revealed an overall survival rate
of 91.6% after 5 years for computer-aided design/computer-assisted manufacture
(CAD/CAM) single-tooth restorations, which is considered clinically similar to conventional restorations. However, the lowest rate was found in endocrowns (82.3%). This
Correspondence to:
Dr Leila Payaminia
Department of Prosthodontics
School of Dentistry, Bushehr
University of Medical Sciences
Moallem St, Bushehr, Iran
Fax: +987733322206
Email: leilapayaminiya@yahoo.com
Dr Marzieh Alikhasi
Department of Prosthodontics
School of Dentistry, Tehran
University of Medical Sciences
North Amirabad St, Tehran, Iran
Fax: +982188196809
Email: m_alikhasi@yahoo.com;
malikhasi@razi.tums.ac.ir
Submitted February 18, 2019;
accepted September 14, 2019.
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341
Fundamental Research
admits the concern that endocrowns might not always
represent a predictable alternative treatment option, as
Bindl et al7 and Otto and Mörmann8 declared regarding
premolar endocrowns. In contrast, there are some studies that have reported a survival rate of > 90% for endocrowns, showing no significant differences between
premolars and molars.4,9 However, as the endocrown
concept was introduced about two decades ago, there
are not sufficient long-term study results with large
sample sizes on endocrown survival and success rates.
Although endocrowns have both macro- and micromechanical retention,3 their retention mainly relies on
bonding; so, it is essential to use materials that can be
bonded to tooth structure.10
CAD/CAM technology has witnessed widespread advances in materials over the past 10 years.5 Glass- and
composite-based materials are the main categories of
adhesive ceramics that can be used with CAD/CAM technology. Glass-based materials are nonmetallic inorganic
ceramic materials that contain the glass phase. Lithium
disilicate and its derivatives, including zirconia-reinforced
lithium silicate (ZLS), are categorized into this group.
Composite-based materials are categorized into different subgroups—polymer-infiltrated ceramic network
(PICN) and composite resin—according to their chemical
composition. The first is composed of a dual network:
a dominant ceramic network infiltrated by a polymer
network. The latter is comprised of materials with an
organic matrix highly filled with ceramic particles.11
IPS e.max CAD (Ivoclar Vivadent) is a lithium disilicate
available in partially crystallized block form that proceeds with crystallization at 850°C after milling with
0.2% shrinkage. VITA Suprinity (VITA Zahnfabrik) is
a ZLS ceramic enriched with highly dispersed zirconia
(10% by weight) and is available in a partially crystallized
form that contains lithium metasilicate crystals; therefore, it can be milled easily.12 Adding zirconia results
in a round and slightly elongated crystalline structure
with an average crystal size of 0.5 µm compared to the
needle-shaped, interlocked, randomly oriented crystals
with an average size of 1.5 µm found in lithium disilicate ceramic.13 VITA Enamic (VITA Zahnfabrik) is a PICN
material with 14 by weight polymer and two distinct
interpenetrating phases. This material was introduced
to overcome the high modulus elasticity, hardness, and
brittleness of glass-matrix ceramics. A more favorable
brittleness index of this material makes it a suitable option for milling units compared to lithium disilicate and
ZLS materials.14 Furthermore, these hybrid ceramics require less preparation of the tooth structure to provide
sufficient durability.15
The marginal adaptation of indirect restorations is
an important factor for clinical long-term success. The
presence of a marginal gap can lead to dissolution of
the luting agent, secondary caries, and periodontal
342
disease.16–18 A marginal gap of less than 120 μm is
considered clinically acceptable.19 In addition, the internal gap can also affect the clinical outcome because
internal gaps greater than 70 μm can reduce the fracture resistance of dental crowns.20 However, there is
no consensus on an acceptable threshold for internal
gap.21 As a result, it is important to address two questions when restoring endodontically treated teeth:
(1) Which restoration is preferable? and (2) Which
material should be chosen to achieve highly adapted
restorations? The purpose of this study was to evaluate and compare the marginal and internal adaptation
values of chairside CAD/CAM (CEREC) endocrowns
and crowns fabricated of lithium disilicate (IPS e.max
CAD), ZLS glass-ceramic (VITA Suprinity), and hybrid
ceramic (VITA Enamic). The null hypothesis was that
there would be no difference in the internal and marginal adaptations between CAD/CAM endocrowns
and crowns of these three materials.
MATERIALS AND METHODS
A sample size of 12 was calculated for each group for
80% power according to the two-sample t test power
analysis (PASS 11), assuming the reported mean and
standard deviations (SDs) reported by Shin et al22 (mean
= 100 µm, SDs = 98 µm and 60 µm). A total of 72 specimens were used in this study, divided into two groups:
36 crowns and 36 endocrowns. The crown type groups
were further divided into three subgroups each based
on material: IPS e.max CAD, VITA Suprinity, and VITA
Enamic (n = 12 each).
Tooth Selection and Preparation
Dental models of the two first maxillary molars (Nissin
Dental Products) were selected. The teeth were embedded with self-curing acrylic resin (Fastray, Harry J. Bosworth) to 2 mm below the cementoenamel junction in
an aluminum base with specified geometric features. In
order to reproduce the surface anatomy, both models
were scanned using an intraoral scanner (CEREC Omnicam, Dentsply Sirona). One of the teeth was prepared to
receive an endocrown restoration. Accordingly, the buccal and lingual cusps received 3-mm and 5-mm occlusal
reductions, respectively, with butt-joint margin designs.
A tapered fissure diamond bur (G845KR, Edenta) was
used to create the internal taper of the pulp chamber,
which was 8 to 10 degrees in the mesial and distal, 22
degrees in the buccal, and 11 degrees in the lingual cavity walls. The depth of the cavity from the lingual wall
was considered to be 3 mm. The finishing procedure
was accomplished using a bur (806314141014 fine,
Jota) with the same shape and taper, a larger diameter,
and a finer particle size to allow for smooth internal
transitions.
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Hasanzade et al
Fig 1 Digital die of crown.
Fig 2 Digital die of endocrown.
The other tooth was prepared for a standard allceramic crown. Preparation consisted of a 2-mm reduction of the occlusal surface and a 1-mm reduction of all
the axial walls with a deep chamfer finish line using a
round-end taper diamond bur (806314290 coarse, Jota).
The preparation was completed after the finishing procedure with a fine diamond bur (806314290 fine, Jota).
were obtained using the industrial noncontact ATOS
scanner (ATOS III Triple Scan, GOM). First, the die and
base, which had a star-shaped configuration, were
scanned. In the second step, the restoration was placed
on the die and fixed with light-body silicone (Speedex,
Coltène). Then, the assembly of restoration, die, and
base was scanned. In the third step, a hexagon-shaped
cylindrical index was fixed on the top of the restoration, and the assembly was scanned again. Finally, the
restoration was removed from the tooth with an index
in its place, and the inner and outer surfaces of the
endocrown/crown and the hexagon-shaped index were
scanned. GOM software (Inspect 7.5) was used to analyze the dataset of each specimen using the reference
model–matching technique. The superimposition of the
mesh data was done with reference points on the hexagon-shaped and star-shaped indices of the base, which
were equal for all samples in each scan. After processing the data, a uniform scan of the restoration seated
on the die was obtained. Each model was sectioned
mesiodistally and buccolingually across the intersecting
edge of the star in the base. Each section was measured
in the marginal, mid-axial wall, and occlusal/floor sites.
Scan and Design
Data from each of the two models were captured using
an intraoral scanner (Figs 1 and 2). The endocrown and
crown were designed with CEREC premium SW v.4.0
software (Dentsply Sirona) using initial scans before
preparation as master models and a biogeneric copy
design option. A 60-μm cement space was considered
in all of the groups.
Restoration Fabrication
The digital information was transferred to the milling
machine (CEREC MC XL, Dentsply Sirona). A total of 72
restorations, including 36 endocrowns and 36 crowns
made of IPS e.max CAD, VITA Suprinity, and VITA Enamic (n = 12 in each subgroup), were fabricated.
The restorations made of IPS e.max CAD and VITA
Suprinity blocks needed an additional crystallization
step. Therefore, they were placed in a furnace (CEREC
SpeedFire, Dentsply Sirona) at 840ºC for 25 minutes.
Measurement of Marginal and Internal
Adaptations
Before measurement, in order to reach a maximum
adaptation, the proper seating of the restorations was
verified until achieving the best possible fit using a disclosing media (Kettenbach). Restorations were adjusted
if needed under magnification by a dental loupe. A reference point–matching scan protocol was performed
for three-dimensional (3D) fit assessment. Four scans
Data Analysis
Data were analyzed using statistical software (SPSS
22.0, IBM). Normality distribution was checked using
Kolmogorov-Smirnov test. Group means and SDs were
calculated for all the measurements obtained from the
mesial, distal, buccal, and lingual marginal and axial wall
discrepancies and for occlusal/floor discrepancies. In addition to the mean values at each region, the total marginal, axial, and occlusal/floor discrepancies were also
calculated using the mean of the values obtained from
all the regions for each group. Multivariate analysis of
variance (MANOVA) was performed to investigate the
following questions: (1) What are the main effects of
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343
Fundamental Research
Table 1 Interpretation of
Effect Size Values
Table 2 Mean and Standard Deviation Marginal, Axial, and Occlusal/Floor
Gaps (μm)
Values
Interpretation
0.01
Small effect
Marginal
IPS e.max
0.06
Moderate effect
Axial
0.14
Large effect
Occlusal/floor
IPS e.max
VITA Suprinity
VITA Enamic
140
Marginal discrepancy
Crown
Endocrown
Crown
Endocrown
Crown
Endocrown
120
100
80
60
40
20
0
Endocrown
Crown
Restoration
Fig 3 Mean and standard deviation total marginal discrepancies of
two restoration types and three restoration materials.
IPS e.max
VITA Suprinity
VITA Enamic
Axial discrepancy
140
120
100
80
60
40
20
0
Endocrown
Crown
Restoration
Occlusal/floor discrepancy
Fig 4 Mean and standard deviation total axial wall discrepancies of
two restoration types and three restoration materials.
IPS e.max
VITA Suprinity
VITA Enamic
350
300
250
200
150
100
50
0
Endocrown
Crown
Restoration
Fig 5 Means and standard deviation total occlusal/floor discrepancies of two restoration types and three restoration materials.
344
65.93 ± 26.42
69.22 ± 23.49
71.72 ± 17.17
70.18 ± 14.03
222.66 ± 58.67
102.62 ± 26.30
VITA Suprinity
77.88 ± 36.68
77.52 ± 13.39
74.13 ± 20.57
73.36 ± 19.86
230.50 ± 65.51
100.04 ± 14.93
VITA Enamic
56.09 ± 16.68
71.00 ± 31.76
80.72 ± 19.35
77.16 ± 23.78
204.09 ± 36.59
93.91 ± 44.62
independent variables (restoration type and restoration
material)? and (2) What is the interaction between the
independent variables (restoration type and restoration
material)? When MANOVA was significant, a univariate
test was run for each variable (mesial, distal, buccal, and
lingual) to interpret the respective effect. The results of
between-subject effects tests were used to answer the
above questions. In all analyses, the significance level
was set to P ≤ .05. Partial eta-squared analysis was also
used to estimate the effect size. The interpretations of
eta-squared values are presented in Table 1.
RESULTS
Three specimens, including one VITA Suprinity endocrown, one VITA Enamic crown, and one VITA Suprinity
crown, were excluded due to rocking after the adjustment. The mean values of the descriptive analyses of the
margin, axial, and occlusal/floor discrepancies are summarized in Table 2 and are also shown graphically in Figs
3 to 5. The results indicated that the range of marginal
discrepancies was 23.55 μm (buccal aspect of VITA Enamic crown) to 110.55 μm (distal aspect of VITA Suprinity crown), and the mean marginal gaps in all six groups
were less than 80 μm. The MANOVA result was not
significant for the margin discrepancies (P > .05), implying that the changes of the four points were highly correlated. However, the multivariate result was significant
for axial wall discrepancy (P < .001). Therefore, the four
axial points were separately analyzed. The betweensubject effects tests showed that there was no significant difference in the marginal, buccal, or lingual axial
wall discrepancies between crowns and endocrowns.
The mesial axial wall discrepancy was significantly lower
in the endocrowns compared to the crowns (P < .001,
partial eta squared = .301), while the distal axial wall
discrepancy was significantly higher (P < .001, partial
eta squared = .198). Furthermore, floor discrepancy was
found to be significantly lower in endocrowns compared to the occlusal discrepancy in the crowns (P <
.001, partial eta squared = .664). In the marginal, axial,
and occlusal/floor discrepancy analyses, no significant
differences were observed among the three materials.
Moreover, the interaction between restoration type and
restoration material was not always significant.
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Hasanzade et al
DISCUSSION
In the scenario of restoring severely damaged endodontically treated teeth, the challenging decision that determines the long-term success of the treatment is what
type of restoration and material best meet the esthetic,
biologic, and functional requirements. In addition to
the many other factors that contribute to the answer to
this question, the marginal and internal adaptations are
decisive factors. It has been demonstrated that different
factors, such as type of scanner, type of milling machine,
cement space, design of preparation, type of material,
and measuring method, could influence the marginal
and internal discrepancies.23–25 In this study, the effect
of restoration type (crowns and endocrowns) and material (IPS e.max CAD, VITA Suprinity, and VITA Enamic)
were investigated by considering all other factors equal
in all samples. The null hypothesis was partially rejected.
While neither type of restoration nor material affected
the marginal gap, the internal gap was affected by the
type of restoration regardless of the type of material.
The results indicated that the endocrowns had statistically higher floor adaptation in comparison to the occlusal adaptation of the crowns and that the mesial axial
wall discrepancy was higher in the crowns than in the
endocrowns, while the results were vice versa for distal
axial wall discrepancy. It should be noted that partial
eta-squared analysis showed that the effect sizes were
large (> 0.14) in these three dependent variables.
The marginal and internal adaptations of CAD/CAM
restorations depend on how accurately the scanner can
capture the data and how precisely the milling machine
can grind the blocks. The geometry of the preparation
could affect data capture. Crowns and endocrowns are
completely different in preparation, since a prepared die
for a crown is a projected object with approximately
parallel walls, while endocrowns have a cavity and the
accuracy of the scan depends on the cavity depth. The
other point is the access direction of the scanner, as
digital impressions are imperfect on the distal side at
a specific angle. The access direction creates a shadow
distal to the illuminated object, which is called the distal shadow phenomenon. However, the tooth structure
is placed in reverse in endocrowns. This theoretically
might cause a shadow on the mesial cavity surface.26
Machinability of blocks can be defined as the ease with
which a given material is cut, which depends on the
brittleness index, which can be derived from the hardness and fracture toughness, chipping factor, and microstructure of the material.27,28 It was found that the
penetration rate of a cutting bur was higher in polymercontaining ceramics than IPS e.max and ZLS ceramics29
and that low hardness and modulus of elasticity were
associated with greater amounts of material being removed during grinding.30 In addition, the other factor is
resistance to crack propagation during grinding, which
is correlated with flexural resistance.31
The results showed that neither type of restoration nor restoration material significantly affected the
marginal discrepancy. The mean marginal gaps in all
six groups were less than 80 μm. This result could be
mainly due to the fact that the distal shadow phenomenon was limited by using a single tooth mounted in
an aluminum base and/or that measurements were
done after the adjustment. To the authors’ knowledge,
there is no previous study that compares crowns and
endocrowns fabricated of different materials considering the marginal and internal adaptations. As a result,
comparing the present results to existing studies was
done separately for each restoration type.
Yildirim et al25 measured the vertical marginal discrepancy (absolute marginal discrepancy [AMD]), the
horizontal marginal discrepancy (MD), and the axial and
occlusal discrepancies of crowns made of different materials. They found that the AMD values for the IPS e.max
(155.5 μm), VITA Enamic (102 μm), and VITA Suprinity
(132 μm) crowns were higher than the present values of
the IPS e.max (65.93 μm), VITA Enamic (56.09 μm), and
VITA Suprinity (77.88 μm) crowns. However, the range
of axial (70.18 to 80.72 μm) discrepancies and the mean
occlusal (219 μm) discrepancy in the present study fell
outside the range of 41.5 to 51.7 μm and outside the
mean value of 191.5 μm in Yildirim et al.25 These results
are contrary to the Yildirim et al findings, which suggest that the discrepancy values of the IPS e.max CAD
crowns were significantly higher than those made of
VITA Suprinity and that the discrepancy values of Lava
Ultimate and VITA Enamic blocks were significantly lower than those of others.25 These conflicting results are
due to whether the restorations were adjusted and the
amount of spacer, which was set at 40 microns in their
study. As a result, a lower cement space led to a higher
marginal gap and a lower axial discrepancy.
Shin et al22 measured the marginal and cavity wall
discrepancies of IPS e.max CAD endocrowns according to the cavity depth. The range of the marginal gap
(99 to 120 μm), the axial discrepancy (118 to 152 μm),
and the pulpal floor discrepancy (229 to 243 μm), were
all slightly higher than the marginal (69.22 μm), axial
(70.18 μm), and floor (102.62 μm) discrepancies of the
IPS endocrowns in the present study. This could be attributed to a difference in the internal taper of the cavity walls, which was higher in the present study.
Moreover, the floor discrepancy in the present study
was found to be significantly lower in the endocrowns
compared to the occlusal discrepancy in the crowns. This
result is probably due to the flat surface of the pulpal
floor in endocrowns, while occlusal reduction of crowns
follows anatomical planes, and these details in the occlusal surface lead to overmilling of the restoration.
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Fundamental Research
It was found that the measurement technique can
affect the marginal and internal values.23 A novel technique was used in this study in order to improve the
previous version of digital measurement techniques. A
hexagon-shaped occlusal index and star-shaped basal index were used as reference points to correlate the mesh
data more accurately. In a triple-scan protocol, scans are
correlated according to surface point matching, which is
not as accurate as reference point matching.
One of the limitations of the present study was that
all discrepancies were measured without luting cement.
It has been revealed that marginal discrepancy mostly
increases after cementation. The vertical marginal discrepancies of all-ceramic crowns nearly doubled once
cemented.32 However, in Shin et al’s22 study, the discrepancy was reduced or did not change. Even with
the additional gap caused by cementation, the present
results seem to be still in a clinically acceptable range.
Since cements have a certain thickness, evaluations
should also be accomplished after cementation. Another limitation was that only the vertical marginal discrepancies were assessed; however, it is better to assess the
vertical and horizontal discrepancies differently because
they have different clinical implications.
Currently, the “replica technique” is the only 3D technique for evaluation of restoration adaptation in clinical
studies. The noncontact scanning technique used in this
study, although more accurate, could only be used in
vitro. It is important to consider that due to the inherent limitations of in vitro studies, the results could not
be simply generalized to a clinical situation, and further
clinical studies are recommended.
CONCLUSIONS
Based on the present in vitro study, neither type of restoration nor material affected the marginal gap. However,
the internal gap was affected by the type of restoration.
As a result, the endocrowns had higher floor and mesial adaptation and less distal adaptation in comparison
with the crowns. Both kinds of restoration made of all
three materials exhibited a clinically acceptable range
for the marginal and internal adaptation values.
ACKNOWLEDGMENTS
The authors report no conflicts of interest.
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Literature Abstract
Factors Related to the Outcomes of Cracked Teeth After Endodontic Treatment
Cracked teeth are a common clinical finding; however, their presence renders diagnosis and prognosis unreliable. The purpose of this
research was to assess the correlations of multiple factors on the prognosis of cracked teeth that had undergone endodontic treatment. A
total of 3,680 patients who received endodontic treatment from an advanced postdoctoral education program in endodontics with followup records of at least 1 year were assessed. From this sample, 62 patients met the inclusion criteria and were included in the final analysis.
The factors evaluated included demographics, clinical symptoms and signs, radiographic findings, and restoration type. Statistical analysis
was then completed using chi-square and Fisher exact tests. The mean follow-up period was 23.3 months, with an overall tooth success
rate of 75.8%. The success rates differed significantly when the patient had an existing preoperative periapical lesion, lacked a proper
permanent restoration on the treated tooth, or had a post placed after root canal treatment. Data analysis showed that restoring the tooth
after endodontic treatment was the single most important factor for prognosis. In fact, the endodontically treated teeth with definitive
full-coverage restorations had a 2-year success rate of 93.6%. Full-coverage restorations should be considered an important part of the
treatment plan for cracked teeth treated endodontically.
Chen YT, Hsu TY, Liu H, Chogle S. J Endod 2021;47:215–220. References: 30. Reprints: S. Chogle, schogle@bu.edu —Ray Scott, USA
Literature Abstract
Application of Artificial Intelligence in Dentistry
Artificial intelligence (AI) is a technology that utilizes machines to mimic intelligent human behavior. To appreciate human-technology
interaction in the clinical setting, augmented intelligence has been proposed as a cognitive extension of AI in health care, emphasizing its
assistive and supplementary role to medical professionals. While truly autonomous medical robotic systems are still beyond reach, the virtual
component of AI, known as software-type algorithms, is the main component used in dentistry. Because of their powerful capabilities in
data analysis, these virtual algorithms are expected to improve the accuracy and efficacy of dental diagnosis, provide visualized anatomical
guidance for treatment, simulate and evaluate prospective results, and project the occurrence and prognosis of oral diseases. Potential
obstacles in contemporary algorithms that prevent routine implementation of AI include the lack of data curation, sharing, and readability;
the inability to illustrate the inner decision-making process; the insufficient power of classical computing; and the neglect of ethical
principles in the design of AI frameworks. It is necessary to maintain a proactive attitude toward AI to ensure its affirmative development
and promote human-technology rapport to revolutionize dental practice. The present review outlines the progress and potential dental
applications of AI in medical-aided diagnosis, treatment, and disease prediction and discusses their data limitations, interpretability,
computing power, and ethical considerations, as well as their impact on dentists, with the objective of creating a backdrop for future
research in this rapidly expanding area.
Shan T, Tay FR, Gu L. J Dent Res 2021;100:232–244. References: 60. Reprints: FR Tay, ftay@augusta.edu —Carlo Marinello, Switzerland
Volume 34, Number 3, 2021
© 2021 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY.
NO PART MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.
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