The Impact of Digital Workflows on the Design of Fixed Prostheses: A Systematic Literature Review

Abstract

Introduction

The digital transformation in dentistry has profoundly changed the design protocols for fixed, tooth-supported prostheses. The integration of computer-aided design and manufacturing (CAD/CAM) technologies raises the question of their effectiveness compared to conventional methods. The objective of this systematic review is to analyze, through a review of the literature, the impact of the digital workflow on the design of fixed prostheses in comparison with the conventional workflow.

Materials and Methods

A literature search was conducted in the PubMed and Scopus databases over a 10-year period (2016–2026). The following inclusion/exclusion criteria were applied: in vivo and in vitro studies focusing on tooth-supported fixed prostheses that evaluated either digital impressions or a fully digital workflow, comparing it to a conventional workflow. Studies were selected following the PRISMA chronology (identification, selection, eligibility, inclusion). Extracted data included: study characteristics, sample type, objectives, evaluated outcomes, quantitative results, measurement methods, and conclusions.

Results

A total of 11 studies were included in this review. The analysis of the results highlights significant heterogeneity in methodologies and evaluation criteria, particularly regarding impression accuracy, marginal adaptation, chairside time, and reproducibility. Overall, the available data do not provide sufficient evidence to demonstrate the superiority of the digital workflow over the conventional workflow. However, some studies suggest comparable, or even superior, performance of the digital workflow under specific conditions.

Conclusion

Digital design of fixed prostheses offers an alternative to traditional conventional methods. However, the lack of consensus and the heterogeneity of current data do not allow for the confirmation of its superiority. Standardized long-term clinical results are needed to confirm these findings and clarify the optimal indications for the digital workflow.

Introduction

Tooth-supported fixed prostheses are a central element of oral rehabilitation, aiming to restore masticatory function, aesthetics, and patient comfort. Traditionally, their design relies on a conventional workflow involving analog impressions, stone casts, and laboratory fabrication—Processes that may accumulate inaccuracies throughout each stage.

The introduction of digital technologies has profoundly transformed these design and fabrication protocols for fixed prosthetic restorations. The shift from conventional to digital workflows, particularly through computer-aided design and manufacturing (CAD/CAM) systems, offers the potential for improved accuracy, reduced human error, streamlined clinical steps, and time savings, thus promoting its increasing adoption in daily clinical practice.

However, despite this enthusiasm, the clinical added value of the digital workflow compared to the conventional method remains a subject of debate.1–3 The literature reports sometimes contradictory results due to the heterogeneity of protocols, systems used, and evaluation criteria, particularly in terms of accuracy, marginal adaptation, and clinical efficacy.

In this context, it is relevant to question the actual benefits offered by these technologies compared to traditional methods in fixed prosthodontics. To address this problematic, this systematic review, conducted in accordance with PRISMA recommendations, aims to evaluate the impact of digital workflow on the design parameters of tooth-supported fixed prostheses, compared to conventional workflow, using a structured approach based on the PICO model.

Methodology

Search Strategy

Question Type

The objective of this study is to prove the effectiveness of an innovative protocol (digital flow) by comparing it to the basic protocol (conventional flow), The research question is thus of a therapeutic nature.

PICO Method

In order to structure the research and to address the problem precisely, the research question was formulated using the following PICO framework:

Population (Population): Patients requiring restoration with a tooth-supported fixed prosthesis, as well as experimental models from in vitro studies.

Intervention (I): Digital workflow for the design and fabrication of prostheses (digital impression, CAD/CAM, complete digital workflow).

Comparison (C): Conventional or semi-conventional workflow (analog impression, traditional laboratory technique).

Outcomes (O): Primary outcomes: Marginal fit (marginal gap), Internal fit (internal adaptation), Anatomical morphology/proximal contacts.

Secondary outcomes: Design parameters (cement space, offset), Maximum thickness control, Design time, Quality of the scan integrated into the design, Periodontal health, Patient and clinician satisfaction.

Formulation of the Final Research Question

In patients requiring a fixed tooth-supported prosthesis, how does the digital design and manufacturing workflow improve clinical and technical performance compared to the conventional workflow?

Databases and Keywords

Databases

For article searches, the PubMed and Scopus bibliographic databases were used because they allow for structured and reproducible searches based on structured queries (AND OR NOT), indexed controlled vocabulary (indexed mesh words, etc), and transparent filters.

Moreover, they provide access to scientifically validated, peer-reviewed articles based on solid evidence.

All of this ensures the reproducibility and traceability of the bibliographic search, providing the systematic review with a suitable methodological standard.

Keywords and Queries

In order to select all relevant articles on the topic, the search strategy relies on keywords referring to fixed prostheses and digital workflows.

For the PubMed database, these keywords are combined with indexed MESH terms (Medical Subject Headings), while Scopus uses free-form keywords.

Among the identified keywords: Computer-Aided Design, Digital Impression, Intraoral Scanner, Digital Workflow, Digital Dentistry, and Fixed Dental Prosthesis. These keywords will then be combined using Boolean operators (AND, OR, NOT) to construct the search queries.

The literature search was conducted in February 2026.

Pubmed

(Dental Prosthesis, Fixed [MeSH]

OR fixed dental prosthesis [tiab]

OR fixed dental prostheses [tiab]

OR crown and bridge [tiab])

AND (Computer-Aided Design [MeSH]

OR CAD [tiab]

OR digital dentistry [tiab]

OR digital workflow [tiab]

OR intraoral scanner [tiab]

OR digital impression [tiab])

AND NOT (Computer-Aided Manufacturing [MeSH]

OR machining [tiab]

OR milling [tiab]

OR 3D printing [tiab]

OR 3D printer [tiab])

AND NOT (dental implants [MeSH] OR implant* [tiab])

Scopus

TITLE-ABS-KEY(

(“fixed dental prosthesis” OR “fixed dental prostheses” OR “crown and bridge”)

AND

(“computer-aided design” OR “CAD” OR “digital dentistry” OR “digital workflow” OR “intraoral scanner” OR “digital impression”))

AND NOT

TITLE-ABS-KEY(

“machining” OR “milling” OR “3D printing” OR “3D printer”)

AND NOT

TITLE-ABS-KEY (“implant*”)

Inclusion and Exclusion Criteria

The Systematic Review Includes Articles

Studies included in this systematic review had to be published between 2016 and 2026 and focus on tooth-supported fixed prostheses. Only studies with measurable primary data were included, including clinical trials, prospective studies, observational studies (cohorts, cross-sectional studies, and retrospective studies), as well as in vitro experimental studies performed on extracted teeth or models.

Studies were included only if the digital workflow was the primary focus of the investigation and not simply a measurement tool or secondary analysis.

Studies also had to be comparative, either by comparing the global digital workflow to the conventional workflow or by specifically evaluating the data acquisition method, particularly the comparison between direct digital impressions and conventional impressions followed by digitization.

The Systematic Review Excluded the Following Articles

Excluded studies were those focusing on implant-supported fixed prostheses and removable prostheses. Systematic reviews, narrative reviews, meta-analyses, expert opinions, and educational articles were also excluded. Finally, studies focusing only on computer-aided manufacturing (CAM): Fabrication techniques or Manufacturing materials without clinical evaluation were not included.

Study Selection

Study selection follows a chronological sequence of several steps:

• Database search

• Removal of duplicate articles

• Inclusion/exclusion based on the title and abstract

• Removal of studies not available in full text

• Inclusion/exclusion based on the full text

The screening of titles, abstracts, and full texts was performed by the first author according to the predefined inclusion and exclusion criteria.

Risk of Bias and Methodological Quality Assessment

Due to the heterogeneity of the included studies, separate methodological assessments were performed for clinical and in vitro investigations.

Clinical studies were evaluated using key methodological domains adapted from the Cochrane RoB 2 and ROBINS-I frameworks, including selection bias, performance bias, detection bias, and reporting bias. An overall risk level was assigned based on the combined assessment of these domains. The methodological quality assessment of the clinical studies is presented in Table 1.

Table 1.

Assessment of Clinical Studies Based on Key Methodological Domains Adapted from the Cochrane RoB 2 and ROBINS-I Frameworks

Study	Design	Selection Bias	Performance Bias	Detection Bias	Reporting Bias	Overall Risk
Karasan et al4	RCT	Moderate	Moderate	Low	Low	Moderate
Chopra et al5	Non-RCT	Moderate	Moderate	Moderate	Low	Moderate
Nandhini et al6	RCT	Moderate	Moderate	Low	Low	Moderate
Avetisyan et al7	Non-RCT	Low	Low	Moderate	Low	Low-moderate

For in vitro studies, a methodological quality assessment adapted for prosthodontic laboratory investigations was performed. The assessment considered study standardization and reproducibility, and an overall methodological quality rating was assigned to each study. The methodological quality assessment of the in vitro studies is presented in Table 2.

Table 2.

Methodological Quality Assessment Adapted for in vitro Prosthodontic Studies

Study	Model	Standardization	Reproducibility	Overall Quality
Bandiaky et al8	In vitro	High	High	Low
Dahl et al9	In vitro	Moderate	Moderate	Moderate
Liang et al10	In vitro	Moderate	Moderate	Moderate
Uluc et al11	In vitro	Moderate	Moderate	Moderate
Su et al12	In vitro	Moderate	Moderate	Moderate
Arezoobakhsh et al13	In vitro	Low-Moderate	Moderate	Moderate-high
Shenoy et al14	In vitro	Moderate	Moderate	Moderate

Data Extraction

The data collected after analyzing the full text are summarized in Table 3 to highlight the following characteristics:

• Article title/Authors/Year of publication

• Study type/Sample studied

• Study objective and outcomes studied

• Numerical results

• Comparative conclusion

• Measurement method

Table 3.

Summary Table

Title Year Study Type	Populations/Type of Prosthesis	Objective and Outcomes Studied	Comparison Groups	Results	Comparative Conclusion	Measurement Method
Karasan et al, 20234 (prospective crossover clinical trial (in vivo study))	3-unit posterior bridge	To evaluate the in vivo occlusal adjustment volume using a fully digital workflow compared to a fully conventional workflow	Digital workflow (digital impression + CAD + CAM) and conventional workflow (conventional impression + lost-wax casting + manual layering with feldspathic ceramic) Patient and operator preferences between the two methods	Quantitative analysis: The digital workflow resulted in less occlusal adjustment (7.63 mm3 ± 7.02) compared to the analog workflow (25.95 mm3 ± 39.61). However, the difference between the two groups did not reach statistical significance (P = 0.12). The effect size is 0.189, suggesting a small to moderate difference between the two workflows. The volumetric occlusal adjustment values for analog FPDs showed higher variance and standard deviation than those of the digital group. Qualitative analysis: Monolithic zirconia FPDs = score 0 to 1 = adequate for placement, with half of the restorations requiring less than 0.3 mm of adjustment, thus clinically insignificant. PFM FPDs = 3 restorations (21.4% of PFM FDRs) received a score of 4, meaning that the restorations were inaccurate for placement and required significant occlusal adjustments (75% of the occlusal surface), resulting in a major geometric change, and 1 restoration had a score of 3, therefore requiring important adjustment (50 to 70% of the occlusal surface) Preference: Patients and operators significantly favored the digital workflow (on VAS), both for the impression phase and for comfort during adjustment (P<0.05)	No statistically significant difference was observed between workflows (p = 0.12). However, the authors reported that the digital workflow may provide more predictable occlusal contact accuracy and can be considered a reliable alternative. Patients and practitioners preferred digital over analog	Quantitative analysis: occlusal adjustment volume Qualitative analysis: visual analysis > clinical interpretation of volumetric measurements ≫>analyzed chart and assigned score
Bandiaky et al, 20238 (comparative in vitro study)	5-unit bridge	Evaluate and compare the average values of the marginal and internal fit of 5-unit zirconia-based bridge designed using digital impressions and conventional impressions	Digital impression (intraoral scanner directly on the model) vs semi-conventional impression (conventional impression + plaster model + laboratory scanner)	Marginal fit: DS: 95.03 ± 12.74 μm (Significantly more accurate than CI). CI: 106.2 ± 14.51 μm. Internal fit: No significant difference between DS (103.61 μm) and CI (106.38 μm)	Marginal adaptation: digital impression better than semi-conventional impression Internal adaptation: both techniques are similar	Silicone replication technique combined with microtomography Measurements at the marginal and internal zones
Dahl et al, 20179 (in vitro study)	3-unit bridge	Compare the fit of the internal components of three-unit FDP frameworks manufactured using five different CAD/CAM systems with those manufactured using conventional techniques (lost-wax casting and metal casting)	Digital workflow (digital impression + CAD + CAM: milling in 5 different materials) and conventional workflow (conventional impression + lost-wax casting + cobalt-chromium metal casting) More specifically, production techniques: Milling Laser sintering Conventional	Cement space (Fit accuracy): Marginal/cervical fit: The M-Co-Cr group (machined cobalt-chrome) has the smallest space (best accuracy), followed by zirconia (Zir and HIP-Zir) Internal fit (buccal-palatal and disto-mesial sections): The best results are obtained with the HIP-Zir group (hot-pressed zirconia). Overall fit (FDP): The C-Co-Cr group (conventional cobalt-chrome) showed the most precise external fit, he M-Co-Cr (machined) group showed the most precise internal fit.	Similar No difference between the three production techniques	Triple-scan method 2 sections, each with 5 subsections
Chopra et al, 20255 (non-randomized experimental clinical trial (in vivo study))		Evaluate and compare the reproduction of details scanned by Intraoral scanner iOS and scanned model for three types of finish lines	Digital impression and conventional impression (conventional impression + plaster model + iOS scan)	Reproduction of the margin line (IOS vs conventional impression): Supragingival and juxta-gingival (equigingival) lines: The intraoral scanner (IOS) gives 100% reproduction The model scan gives 50% reproduction; The difference between the proportions was statistically significant (p < 005). Subgingival lines: The intraoral scanner (IOS) gives 40% reproduction The model scan gives 50% reproduction. The difference between the proportions was not statistically significant (p > 0.05) The use of a gingival retraction cord improves the scanner’s accuracy for equigingival and subgingival lines, thus approaching the accuracy of conventional impressions in subgingival areas.	For the Equi and Supraging finishing lines: intraoral scanning is better than conventional impressions For the subgingival line: similar > Accuracy depends on the position of the finishing line	Visual evaluation using software *Based on continuity criteria *Blind test
Liang et al, 202310	3-unit ceramic bridges	Quantitatively Quantitatively analyze the absolute marginal discrepancy (AMD) of 3-unit ceramic bridges fabricated using conventional and digital technologies	Digital workflows (digital modeling + CAD + CAM) and conventional workflows (Conventional polyether impression + hot-pressed lost-wax)	Absolute Marginal Deviation (AMD) - Conventional Method: 106.69±6.46μm Digital Workflow: 102.55±6.96μm No statistically significant difference (p > 0.05)	Similar AMD Both are clinically acceptable	Digital footprint and open-source software Calculation of the AMD on a 100-point scale
Uluc et al, 202111 (in vitro study)	5-unit monolithic zirconia bridges	Evaluate the marginal and internal fit of monolithic zirconia 5-unit FPDs fabricated using CAD and CAM technologies, employing direct (Intraoral) and indirect (laboratory) scanning methods as well as 3D deviation analysis	Digital impression (direct scanning) with 3Shape and CEREC and Semi-conventional impression (indirect scanning) with: Impression scan with 3Shape and CEREC Model scan with 3Shape and CEREC	Comparison of workflows (Direct vs Indirect) and scanners: Comparison of the 6 scan streams (two direct and four indirect): No statistically significant differences were observed in any of the regions between the 6 groups (p > 0.05), with the exception of two groups (axial region between the 3S-IMP and C-IOS groups). When the impact of the scanner type (3Shape versus Cerec) on the divergence values was assessed, the mean divergence values in the marginal zone were not significantly different (p > 0.05) between the two groups, but the corresponding values were significantly different in the axial and occlusal zones (p < 0.05).	Direct and indirect impressions have similar marginal and occlusal fit Marginal region: the smallest gaps Occlusal region: the largest gaps Therefore, the marginal fit is better than the occlusal fit	3D superimposition analysis 1900 measurement points
Arezoobakhsh et al, 202013 (in vitro study)	3-unit zirconia bridges	Compare the marginal and internal fit of 3-unit zirconia restorations fabricated using CAD/CAM technology with conventional impressions versus digital scans	Digital impression: intraoral scan of the preparation: Using Trios Using CS3600 And conventional impression: Conventional impression with lab scan) Plaster model with lab scan	Comparison of Intraoral (TRI, CSI) vs Indirect (CIL, DCL) Methods: Marginale fit: The marginal gap was significantly higher in the DCL group (106 ±45 µm) than in all other groups (p < 0.01). The marginal gap between the TRI and CSI groups was not significantly different (p > 0.01). The marginal discrepancy in the CIL group was significantly lower than in the DCL group (P < 0.01), but was significantly higher than in the TRI and CSI groups (P < 0.01) Internal gap Internal gap at the medio-occlusal and axio-occlusal locations did not differ significantly between CIL and DCL groups (p > 0.01). Internal gap was significantly higher in CIL and DCL groups than in TRI and CSI groups (p < 0.01). Internal gap at MO and AO locations was significantly lower in the TRI group than in the CSI group (p < 0.01). The Duncan test showed that while the internal gap at the MA position was similar for the TRI and CSI groups (p > 0.01), it was significantly lower than the gap recorded for the CIL and DCL groups (p < 0.01) Impact of the tooth: Internal gap at the MA position for premolars was similar between TRI and CSI groups (p > 0.01) but these values are significantly lower in TRI and CSI groups than in CIL and DCL groups (p < 0.01). On molar abutments, the largest MA discrepancy was recorded in the CIL group ($89 \pm 27 \mu m$), which was significantly higher than those recorded in all other groups (p < 0.01), with the exception of the DCL group	Intraoral scans provide better internal and marginal fit Model scans provide the poorest marginal fit Both are clinically acceptable	Replication method using silicone and a Leica stereomicroscope at 50x magnification 1100 measurements in total
Su et al, 201612 (in vitro study)	3-unit ceramic-fused denture frameworks for the maxilla	To evaluate and compare the marginal and internal fit of 3-unit ceramic fixed prosthesis frameworks fabricated using CAD/CAM technology based on digital intraoral and conventional impressions	Digital impression (Trios intraoral scanner) and conventional impression (3D scanner for plaster models)	P1: Marginal fit: Mean ±SD marginal discrepancy of 64 ±16 mm (61 ±10 mm for canines and 65 ±19 mm for premolars) for the digital group and 76 ±18 mm (73 ±16 mm for canines and 80 ±18 mm for premolars) for the conventional group The Mann–Whitney U-test presented a significantly higher value for the conventional group (P<0.001) P2 P3 P4: Internal fit: Mean internal discrepancy of 110 ±40 mm (111 ±34 mm for canines and 109 ±46 mm for premolars) for the digital group and 134 ±47 mm (132 ±44 mm for canines and 136 ±50 mm for premolars) for the conventional group. The Mann–Whitney U-test presented a significantly higher value for the conventional group (P<0.001)	Digital methods are superior to conventional methods in terms of marginal and internal fit Both are clinically acceptable	Silicone replication method and 50x optical microscope 640 measurement points
Avetisyan et al, 20217 (in vivo study)	Fixed partial dentures Initially, patients were included based on their periodontal status: Healthy Gingivitis Periodontitis	To examine the effects of fixed partial dentures fabricated using different biomaterials and techniques on the health of both healthy and diseased periodontal tissues To study also the relationship between gingival biotype and gingival recession depending on the type of prosthesis	Digital workflow with prostheses made of Cobalt-chromium Zirconia and conventional workflow using cobalt-chromium	The initial level of oral hygiene was poor among participants in all groups At the 1-year follow-up visit after prosthetic rehabilitation, the mean MAPI value remained unchanged in: Patients with periodontitis in Group I (conventionally fabricated Co-Cr metal-ceramic prostheses) and Group II (CAD/CAM-fabricated Co-Cr metal-ceramic prostheses); Patients with gingivitis in Group I. A statistically significant improvement in oral hygiene indicators was observed among patients with gingivitis in all groups. The best oral hygiene outcomes were observed in Group III (CAD/CAM-fabricated zirconia prostheses), both in patients with gingivitis and in those with periodontitis. The type of fixed dental prosthesis influenced gingival and periodontal health Patients who received CAD/CAM-fabricated fixed dental prostheses demonstrated better periodontal outcomes than those rehabilitated with conventionally fabricated fixed partial dentures. The most common complaints reported by patients following rehabilitation with conventional metal-ceramic prostheses were the presence of a dark cervical margin around the crown, discoloration of the marginal gingiva and interdental papilla, as well as gingivitis, all of which were confirmed by clinical examination. Twelve months after prosthetic rehabilitation, significant differences were observed regarding: *The number of healthy sextants, which was higher among periodontitis patients in Group III than among those in Groups I and II; *The number of sextants presenting periodontal pockets of 4–5 mm, which was lower among periodontitis patients in Group III compared with those in Group I. The gingival biotype is an important factor influencing the outcome of prosthetic rehabilitation.	Digital dentistry yields better periodontal results than conventional dentistry In digital dentistry, zirconia yields better results	Periodontal health assessed before and after prosthesis placement using CPI (Community Periodontal Index) and Modified Proximal Plaque Index. To determine gingival biotype: probe transparency method
Shenoy et al, 202314 (in vitro study)	Temporary crowns	Compare the marginal fit of crowns created using a virtual tooth preparation workflow based on CBCT data and an intraoral scan with a digital workflow using an extraoral scan	Digital impression: scan of the virtual restoration using CBCT scan Intraoral scanner scan	The mean marginal space for the three groups was: 113.37 ± 45.758 µm (Group 1 = CBCT) 127.82 ± 43.655 µm (Group 2 = IOS) 107.30 ± 44.893 µm (Group 3 = EOS) Conventional crowns (EOS) showed the lowest mean marginal gap, whereas digital crowns (CBCT and IOS) showed slightly higher values. However, the differences between groups were not statistically significant (P > 0.05), and all values remained within clinically acceptable limits (< 200 µm).	Similar Digital (CBCT and IOS) is an alternative to the conventional method because it allows for: Greater accuracy Shorter treatment time Increased efficiency Better understanding of the procedure and treatment results Greater patient involvement in the treatment process	SEM electron microscope 360 measurement points
Nandhini et al, 20196 (Retrospective clinical study (in vivo study))	Crowns	Compare the occlusal morphology (anatomy and contours) of CAD-designed crowns and manually layered crowns, and evaluate their anatomy and contours at the occlusal level	Digital design (CAD) with monolithic restorations and conventional design using manual layering	Evaluation based on visual observation using: Photographs Occlusal morphology score > In the photographs, the occlusal morphology and the crown contour were analyzed, and a score was assigned A comparison between crown type and crown location shows that the monolithic crown is most commonly used in the posterior region (30%), while the manually layered zirconia crown is more common in the anterior region (35%) A comparison between monolithic crowns and hand-layered zirconia crowns and occlusal morphology (cusp/incisal anatomy) shows that monolithic crowns (397%) have more acceptable anatomy than hand-layered zirconia crowns (27.6%) A comparison of monolithic crowns and hand-layered zirconia crowns with regard to occlusal morphology (overcontoured/undercontoured) shows that monolithic crowns (37.6%) have a better-defined contour compared to hand-layered zirconia crowns (26%)	Both types have satisfactory anatomy and contour Digital technology is an excellent alternative because it presents wide applications Posterior: monolithic is better than hand-layup Anterior: hand-layup is better	Visual examination: based on photographs, the occlusal morphology and the contour of the crown were analyzed, and a score was assigned

A total of 11 studies were included in this systematic review The studies consisted of in vitro studies and clinical trials The distribution of the included studies according to study type is presented in Figure 1

Figure 1.

Distribution of articles by study type.

Results

PRISMA Diagram

The article selection process is illustrated in Figure 2.

Figure 2.

Diagram PRISMA.

Discussion

The objective of this systematic review was to evaluate the impact of digital technology on the design of tooth-supported fixed prostheses in order to determine, through a comparative approach, the added value of digital workflows compared to conventional protocols. Analysis of the available data provides a nuanced understanding of the benefits of digital technology at different stages of the prosthetic workflow.

This systematic review includes studies that focus on the global workflow (from impression to fabrication), others that focuses on the data acquisition method, and finally, an article that specifically examine digital design, comparing it to manual design.

The studies that examine the global workflow compare a fully digital workflow (comprising a digital impression, computer-aided design, and fabrication) with a fully conventional workflow (digital impression, design, and manual fabrication).

Studies focusing specifically on the acquisition method compare direct digital impressions to conventionally taken impressions followed by digitization and a digital protocol. This approach demonstrates a desire to isolate the acquisition method in order to study its effects.

Including both studies examining global workflow and those mainly focused on the acquisition method alone is a strategic choice, as they are complementary and entirely comparable: the quality of the data acquisition method determines the accuracy of the input data for the design software, which directly influences the quality of the prosthetic design.

This cross-comparison provides a global view of the subject: it allows us to assess the impact of digital technology on the different stages that lead to the final prosthetic result.

Only studies evaluating clinical success parameters are included, while studies focusing specifically on technical manufacturing details (material properties, manufacturing protocols, etc) have been deliberately excluded.

Among the evaluation criteria are the fit of the prosthesis at the internal marginal and occlusal level; occlusal morphology; and the effect of the prostheses on the health of periodontal tissues.

Regarding the types of restorations studied, the data mainly concern 3- or 5-unit maxillary or mandibular tooth-supported bridges. Only two studies focus on single crowns, which limits the generalizability of the results to all clinical situations in fixed prosthodontics.

Marginal Adaptation

The articles by Chopra et al (2025), Liang et al (2023), and Shenoy et al (2023) study exclusively marginal adaptation, while the articles by Bandiaky et al (2023), Uluc et al (2021), Arezoobakhsh et al (2020), and Su et al (2016) study both marginal and internal adaptation of fixed prostheses.

Comparing the results of these studies shows that the literature is quite divided on the subject: while Liang et al (2023), Uluc et al (2021), and Shenoy et al (2023) state that marginal adaptation is similar in both groups, Bandiaky et al (2023), Arezoobakhsh et al (2020), and Su et al (2016) state that marginal adaptation achieved with digital workflow is better than that achieved with the conventional workflow.

The article by Chopra et al (2025) states that the marginal adaptation of these two workflows is similar in both groups for subgingival finishing lines, while the digital method shows better results when it comes to supragingival finishing lines.

It should also be noted that no article asserts that marginal adaptation with conventional workflow is superior to that achieved with digital workflow.

Internal Adaptation

The article by Dahl et al (2017) studies exclusively internal adaptation, while those by Bandiaky et al (2023), Uluc et al (2021), Arezoobakhsh et al (2020), and Su et al (2016) study both internal and marginal adaptation.

Analysis of the results from these studies shows a slight superiority of the digital workflow over the conventional one: the articles by Dahl et al (2017), Uluc et al (2021) and Bandiaky et al (2023) state that the internal adaptation obtained by the two workflows is similar, while the articles by Arezoobakhsh et al (2020), and Su et al (2016) state that internal adaptation obtained by the digital workflow is better than that obtained by the conventional workflow.

It should also be noted that no article claims that the internal adaptation obtained by the conventional flow is better than that obtained by the digital flow.

Occlusal Adjustment

The article by Karasan et al (2023) studies occlusal adjustment and states that it is similar for both workflows and that digital therefore constitutes a reliable alternative.

Occlusal Morphology (Anatomy and Contour Shape)

The article by Nandhini et al (2019) compares the occlusal morphology of the two methods and states that they are similar and that the digital method also constitutes a favorable alternative here.

Periodontal Condition

The article by Avetisyan et al (2021) focuses on periodontal health around prostheses designed according to these 2 workflows, and claims that digital gives better periodontal results than conventional.

Patient and Clinician Satisfaction

The article by Karasan et al (2023) states that both patients and operators have a preference for the digital method.

Study Design Considerations

Among the eleven included studies, four were clinical studies and seven were in vitro studies. Clinical studies provide evidence under real clinical conditions, whereas in vitro studies allow standardized evaluation of prosthetic parameters under controlled laboratory conditions. Therefore, findings from in vitro studies should be interpreted with caution and should not be directly extrapolated to clinical practice.

Divergence of Results

The divergence in results obtained for the same evaluation criterion can be explained by various factors:

• Studies use different measurement methods: some use the silicone replica method, others use visual assessment, or even clinical assessment with tools such as the CPI (Community Periodontal Index) and the MAPI (Modified Approximate Plaque Index), while others use software and electron microscopes.

• The material used to fabricate the prosthesis: zirconia, ceramic, cobalt chrome can influence the results.

• Each intraoral scanner, each extraoral scanner, and each CAD software program has its own intrinsic factors, and the fact that studies do not use the same brands can therefore impact the results.

In addition, the substantial heterogeneity among the included studies and the limited number of studies available for each outcome prevented meaningful quantitative synthesis, subgroup analyses, or meta-regression. Therefore, the findings were synthesized narratively.

Limitations

Among the limitations of this systematic review are:

• The in vitro studies, which constitute a large proportion of the included studies and therefore do not take into account clinical factors (oral temperature, actual masticatory forces, humidity, etc);

• Apart from marginal and internal adaptation, the other evaluation criteria lack long-term data: they are based on only one article each; this lack of data comparison makes it impossible to draw conclusions with certainty.

Clinical Application of the Results

Analysis of the results shows that the introduction of digital technology in the field of fixed prosthodontics represents an approach offering similar and sometimes even superior results to the conventional method, which can be clinically explained by:

• Streamlining of clinical protocols,

• Optimization of treatment time,

• Reduction of human error through eliminating manual steps,

• Improvement of the patient experience,

Digital technology therefore constitutes a reliable alternative to the conventional method without negating the reliability of the conventional method (both are clinically acceptable).

Outlook

The majority of available studies covering the period from 2016 to 2026 and meeting the inclusion criteria for this review are mostly in vitro studies.

Given the limitations of this type of study, future in vivo studies evaluating these criteria under real clinical conditions should emerge.

Furthermore, a large part of the included studies examines marginal and internal adaptation, which allows for a reasoned comparison of the impact of digital technology on these criteria from different perspectives.

However, other criteria such as occlusal fit, occlusal morphology, patient and operator satisfaction, and periodontal health around fixed prostheses do not benefit from this advantage, which prevents generalizing conclusions regarding the impact of digital technology on these criteria. This opens up new avenues for future research.

Moreover, the number of articles included in this review is a true reflection of what the literature on this subject offers.

In addition, this review focused specifically on the design phase of the digital workflow. Future reviews following the same chronological approach could explore the manufacturing phase in greater depth, including CAD/CAM fabrication processes and their potential influence on prosthetic and clinical outcomes.

Conclusion

This systematic review shows that the introduction of digital tools into fixed prosthesis design protocols does not systematically guarantee superiority of the prosthetic design compared to the conventional method.

However, due to its many clinical and operational advantages, it helps optimize the quality of the workflow.

Abbreviations

FDP, Fixed Dental Prosthesis; CAD, Computer-Aided Design; CAM, Computer-Aided Manufacturing.

Disclosure

The authors report no conflicts of interest in this work.