The color stability and wear resistance of provisional implant restorations: A prospective clinical study.

OBJECTIVES: The aim of the present clinical study was to determine the stability of color and resistance against abrasion and attrition of provisional single implant restorations. MATERIAL AND METHODS: A group of 16 patients were treated with provisional crowns made of Telio CAD. Shortly before the insertion the crowns were photographed and scanned using a 3D-laser scanner. After 8 weeks of clinical usage, the crowns were photographed and scanned again. The vertical occlusal wear and color changes between the restorations were measured. RESULTS: The occlusal plane of the original crown showed a statistically significant reduction of 0.052 mm ± 0.037 mm 8 weeks after placement (p < .05). For the stability of color, a change in red, green and blue was described. All three scopes (red, green and blue) showed a statistically significant reduction (p < .05). CONCLUSIONS: This prospective clinical study showed that Telio CAD experienced a significant occlusal reduction and color change after an intraoral placement of 8 weeks.

Radiographic assessment of the relationship between root canal treatment quality, coronal restoration quality, and periapical status.

OBJECTIVE: The aim of this cross-sectional study was to assess the prevalence of apical periodontitis in root canal treated teeth in Turkish subpopulation and to evaluate the effects of both coronal restoration quality and root canal treatment (RCT) quality on apical periodontitis. MATERIALS AND METHODS: Panoramic images of individuals who applied to our department for different diagnostic reasons were randomly and retrospectively scanned. Total RCT number, RCT quality, type of coronal restoration, restoration quality, periapical status, and total number of teeth were recorded. The criteria used for coronal restorations quality and RCT quality were defined by De Moor et al. and slightly modified by Gunduz et al. Periapical status was assessed by the periapical index developed by Orstavik et al. Pearson's Chi-square test was used for statistical analysis, and the intraobserver agreements were assessed by Kappa coefficients. Values of P < 0.05 were accepted to be meaningful. RESULTS: The total examined teeth number was 6064, of which had 541 (8.9%) RCT. The prevelance of apical periodontitis was 40.5%. The number of adequate RCT was 178 (32.9%), and 138 (77.5%) of them were healthy. The number of adequate coronal restoration was 334, and 62.3% of them were healthy. For the cases that have adequate coronal restorations, there was statistically significant relationship between adequate RCT and periapical status (P < 0.001). CONCLUSION: The prevelance of apical periodontitis was 40.5% and there was statistically significant relationship between adequate RCT and periapical status.

Survival, Reasons for Failure and Clinical Characteristics of Anterior/Posterior Composites: 8-Year Findings.

This retrospective study aimed to compare the annual failure rate (AFR), reasons for failure and factors influencing survival of posterior and anterior composite restorations placed by undergraduate students. Composite restorations placed by undergraduate students were evaluated. The restorations should be in occlusion, with at least one adjacent tooth; and patients should have been present for check-up, with at least 1 annual recall. The investigation was performed in two separate analysis: 1) dental electronic records of 100 patients (n=333 restorations) were selected to assess factors influencing survival; 2) clinical evaluation of 30 patients by examining restorations (n=123) to assess clinical characteristics and failure type distribution. Data were subjected to Kaplan-Meier method, Log-rank test, Cox regression and Fisher's Exact test (p<0.05). After 8-year period, the AFR was 2.62%. There was difference between anterior and posterior restorations (p=0.005), with anterior showing a higher AFR. The patient caries-risk (p<0.001) and the number of surfaces restored (p=0.010) affected restoration survival. The superficial brightness (p=0.029), fracture (p=0.025) and retention (p=0.011) were clinical criteria with differences between anterior and posterior restorations. Income (p<0.001), caries activity (p<0.001), caries risk (p<0.001) and oclusal risk (p<0.001) also influenced on the restorations survival. After 8-year, the AFR of restorations placed by undergraduate students was acceptable and affected by patient risk factors and the position of the tooth in the arch: anterior restorations failed more than posterior.

Survival, reasons for failure and clinical characteristics of anterior/posterior composites: 8-year findings

Abstract This retrospective study aimed to compare the annual failure rate (AFR), reasons for failure and factors influencing survival of posterior and anterior composite restorations placed by undergraduate students. Composite restorations placed by undergraduate students were evaluated. The restorations should be in occlusion, with at least one adjacent tooth; and patients should have been present for check-up, with at least 1 annual recall. The investigation was performed in two separate analysis: 1) dental electronic records of 100 patients (n=333 restorations) were selected to assess factors influencing survival; 2) clinical evaluation of 30 patients by examining restorations (n=123) to assess clinical characteristics and failure type distribution. Data were subjected to Kaplan-Meier method, Log-rank test, Cox regression and Fisher's Exact test (p<0.05). After 8-year period, the AFR was 2.62%. There was difference between anterior and posterior restorations (p=0.005), with anterior showing a higher AFR. The patient caries-risk (p<0.001) and the number of surfaces restored (p=0.010) affected restoration survival. The superficial brightness (p=0.029), fracture (p=0.025) and retention (p=0.011) were clinical criteria with differences between anterior and posterior restorations. Income (p<0.001), caries activity (p<0.001), caries risk (p<0.001) and oclusal risk (p<0.001) also influenced on the restorations survival. After 8-year, the AFR of restorations placed by undergraduate students was acceptable and affected by patient risk factors and the position of the tooth in the arch: anterior restorations failed more than posterior.

Resumo Este estudo retrospectivo comparou a taxa de falha anual (TFA), razões para falha e fatores influenciadores da sobrevida de restaurações posteriores e anteriores de resina composta realizadas por estudantes de graduação. As restaurações deveriam estar em oclusão, com pelo menos um dente adjacente, e os pacientes deveriam ter comparecido a pelo menos 1 consulta anual de retorno. A investigação foi realizada em 2 analises separadas: 1) dados odontológicos de prontuário eletrônico de pacientes (n=333 restaurações) foram selecionados para avaliar os fatores influenciadores na sobrevida; 2) avaliação de 30 pacientes por exame clinico das restaurações (n=123) para verificar as características clinicas e a distribuição do tipo de falha. Os dados foram submetidos a Kaplan-Meier método, Log-rank teste, regressão de Cox e Teste Exato de Fisher (p<0,05). Após o período de 8 anos, a TFA foi 2,62%. Houve diferença entre restaurações anteriores e posteriores (p=0,005), sendo que anteriores mostraram maior TFA. Os fatores de risco à carie (p<0,001) e o número de superfícies restauradas (p=0,010) influenciaram a sobrevida de restaurações. Brilho superficial (p=0,029), fratura (p=0,025) e retenção (p=0,011) foram critérios clínicos com diferenças entre restaurações anteriores e posteriores. Renda (p<0,001), atividade de cárie (p<0,001), risco à cárie (p<0,001) e risco oclusal (p<0,001) também influenciaram a sobrevida. Após 8 anos, a TFA das restaurações realizadas por estudantes de graduação foram clinicamente aceitáveis e afetadas pelos fatores de risco associados ao pacientes e a posição do dente na arcada; restaurações anteriores falham mais do que posteriores.

Biomechanical aspects: Summary and consensus statements of group 4. The 5th EAO Consensus Conference 2018.

OBJECTIVES: The aim of the present publication was to report on the EAO Workshop group-4 discussions and consensus statements on the five reviews previously prepared. These reviews provided the scientific evidence on the effect of crown-to-implant ratio, on reconstructions with cantilevers in fully and partially edentulous patients, on biological and technical complications of tilted in comparison with straight implants, and on the effects of osseointegrated implants functioning in a residual dentition. MATERIAL AND METHODS: The group discussed, evaluated, corrected where deemed appropriate, and made recommendations to the authors regarding the following five reviews submitted: (a) Is there an effect of crown-to-implant ratio on implant treatment outcomes?; (b) Implant-supported cantilevered fixed dental rehabilitations in fully edentulous patients; (c) and in partially edentulous patients; (d) Biological and technical complications of tilted implants in comparison with straight implants supporting fixed dental prostheses; (e) What are the adverse effects of osseointegrated implants functioning among natural teeth of a residual dentition? Based on the five manuscripts and the discussion among the group as well as the plenum members, the major findings were summarized, consensus statements were formulated, clinical recommendations were proposed, and areas of future research were identified. RESULTS: Crown-to-implant ratios ranging from 0.9 to 2.2 did not influence the occurrence of biological or technical complications also in single-tooth restorations. Reconstructions with cantilevers for the rehabilitation of fully and partially edentulous jaws showed high implant and reconstruction survival rates. In contrast, the rate of complications-in particular associated with veneering material-was high during the observation period of 5-10 years. The data reported were primarily derived from studies with high risk of bias. The data for single-implant reconstructions were small. There was no evidence that distally tilted implants were associated with higher failure rates and increased amounts of marginal bone loss. The data supporting these findings, however, were at high risk of bias and frequently incompletely reported. Frequent positional changes occurred between the natural teeth and the implant-supported restorations. These changes were more pronounced in younger individuals, and even though they were reduced with age, they still occurred in adult patients. Even though these changes were frequent, potential implications for the patient are unclear. CONCLUSIONS: The use of single-tooth restorations with crown-to-implant ratio in between 0.9 and 2.2 may be considered a viable treatment option. Multiunit reconstructions with cantilevers are a viable treatment option in fully and partially edentulous patients. Clinicians and patients should be aware, however, that complications are frequent and primarily related to resin material used for veneering. There is some evidence that tilting an implant does affect stability of the implant and the surrounding bone. Treatment options to tilted implants should carefully be considered, as the effect on soft tissues and on prosthesis behavior is poorly reported for tilted implants. Positional changes in the dentition in relation to implant-supported restorations occur frequently. The patient should be informed about the possible need for a treatment related to these changes in the long term.

Group 2 ITI Consensus Report: Prosthodontics and implant dentistry.

OBJECTIVES: Working Group 2 was convened to address topics relevant to prosthodontics and dental implants. Systematic reviews were developed according to focused questions addressing (a) the number of implants required to support fixed full-arch restorations, (b) the influence of intentionally tilted implants compared to axial positioned implants when supporting fixed dental prostheses (FDPs), (c) implant placement and loading protocols, (d) zirconia dental implants, (e) zirconia and metal ceramic implant supported single crowns and (f) zirconia and metal ceramic implant supported FDPs. MATERIALS AND METHODS: Group 2 considered and discussed information gathered in six systematic reviews. Group participants discussed statements developed by the authors and developed consensus. The group developed and found consensus for clinical recommendations based on both the statements and the experience of the group. The consensus statements and clinical recommendations were presented to the plenary (gathering of all conference attendees) and discussed. Final versions were developed after consensus was reached. RESULTS: A total of 27 consensus statements were developed from the systematic reviews. Additionally, the group developed 24 clinical recommendations based on the combined expertise of the participants and the developed consensus statements. CONCLUSIONS: The literature supports the use of various implant numbers to support full-arch fixed prostheses. The use of intentionally tilted dental implants is indicated when appropriate conditions exist. Implant placement and loading protocols should be considered together when planning and treating patients. One-piece zirconia dental implants can be recommended when appropriate clinical conditions exist although two-piece zirconia implants should be used with caution as a result of insufficient data. Clinical performance of zirconia and metal ceramic single implant supported crowns is similar and each demonstrates significant, though different, complications. Zirconia ceramic FDPs are less reliable than metal ceramic. Implant supported monolithic zirconia prostheses may be a future option with more supporting evidence.

Optimizing quality and safety of dental materials.

This paper discusses aspects of quality and safety improvement of the most commonly used dental restorative materials, the resin-based composites. From a patient's perspective, long-lasting resin-based restorations without complications are important. Recurrent caries and fracture are the most common causes for restoration failures. Proper handling and curing of the composites improve the mechanical properties of the restorations and increase safety by reducing exposure to residual methacrylate monomers. A number of compounds have been introduced in restorative materials to reduce the risk of recurrent caries, even though a real breakthrough has not yet been achieved. It is concluded that simple measures may improve the quality and safety of resin-based composite restorations.

Longevity of defective direct restorations treated by minimally invasive techniques or complete replacement in permanent teeth: A systematic review.

OBJECTIVES: This systematic review aimed to verify if there is difference in the longevity of minimally invasive techniques compared to the complete replacement for the treatment of defective direct restorations in permanent teeth. DATA: The data included randomized controlled clinical trials comparing the clinical performance of defective dental restorations treated by a complete replacement technique or minimally invasive techniques on permanent teeth. Evaluation of the risk of bias was performed using the Cochrane Collaboration common scheme for bias and the evidence was qualified using the GRADE tool. SOURCE: A comprehensive search was performed in the electronic databases: PubMed, Scopus, ISI Web of Science, The Cochrane Library, LILACS, BBO, SIGLE, followed by manual search in the reference lists of the included studies, without any restrictions. STUDY SELECTION: From 5554 retrieved studies, 10 met the eligibility criteria and were submitted to data extraction and quality assessment. The repair technique presented similar results to replacement and superior results when compared to sealing. In addition, refurbishment demonstrated to be a useful treatment for localized anatomical form defects. All the studies presented low risk of bias and high quality evidence for repair and refurbishment and moderate for the sealing technique. CONCLUSIONS: The direct restorations treated by the repair, seal and refurbishment techniques did not present a significant difference in clinical longevity in comparison to the replacement technique in permanent teeth with overall moderate quality of evidence. CLINICAL SIGNIFICANCE: The present findings demonstrated that the best treatment for defective restorations is conservative management. The evidence demonstrated here helps and encourages clinicians during the decision-making process. Moreover, it suggests not replacing imperfect restorations, but to managing them in a minimally invasive way, allowing the structure to be preserved.

[Consensus recommendations from Chinese experts on the standard operation procedure of curing light in direct composite resin adhesive restorations].

The curing light in direct composite resin adhesive restorations is a common technique and treatment method in oral clinic. It has many advantages, such as matching the color of the teeth, less removing the hard tissues of the teeth, resistance to abrasion, good masticatory performance and so on. It has almost replaced the traditional amalgam filling in the clinical dentistry repair. However, in clinical practice, improper use of the technique can also lead to increased loss of restorations and postoperative sensitivity. The reason is related not only to the physical and chemical properties of the material itself, but also the operator's lack of understanding and mastering the properties of the light cured material, especially the use rules of the light curing lamp. To this end, in September 2017, the vice chairman of Society of Cariology and Endodontology, Chinese Stomatological Association, professor Liang Jingping, organized a part of professional experts in this field, and invited the chief expert in 3M company, Dr. Joe Oxman, held a meeting about the use principle, operation mode and specification symposium of light curing lamp. Experts at the meeting had a very heated discussion, forming the following consensus.

Comparison of ART and conventional techniques on clinical performance of glass-ionomer cement restorations in load bearing areas of permanent and primary dentitions: A systematic review.

OBJECTIVES: To review the clinical performance of GIC restorations using calculated annual failure rates (AFRs) and qualitative descriptions based on conventional and ART techniques from two aspects: occlusal and approximal cavities in permanent or deciduous posterior teeth. SOURCES: Search strategies were undertaken of the PubMed database from January 1983 to March 2018. Additional articles were collected by hand searching. STUDY SELECTION: The following basic search terms, "(glass ionomer cement) and (clinical performance or survival or ART or atraumatic restorative or high viscosity)" with inclusion and exclusion criteria according to PRISMA flow diagram were used. DATA: A total of 904 articles were initially identified. Finally, 67 articles were included for quantitative and qualitative analysis after applying the inclusion and exclusion criteria. Assessment of risk of bias was performed for all included studies using ROBINS-I. CONCLUSIONS: For single-surface occlusal or multi-surface GIC restorations, the conventional technique showed better survival than ART technique regardless of dentition type (primary or permanent). When comparing the same treatment technique, AFRs of approximal or multi-surface GIC restorations were greater than those of single-surface (occlusal) restorations, irrespective of dentition type. RMGIC-conventional technique seems to be promising for restoring approximal cavities of primary teeth compared to other restorative materials. CLINICAL SIGNIFICANCE: The GIC-ART technique is an alternative option for single-surface (occlusal) restorations in permanent and primary teeth. However, the application of the GIC-ART technique for load-bearing approximal restorations should be carefully considered before employing this option, especially in primary teeth.

[Correspondence between advances of dental composites and adhesives and clinical guidelines for direct restorations].

The longevity of direct adhesive restoration is related to the restorative materials, the patient and the professional. On one hand, dental composites/adhesives have been modified and developed to fulfill the criteria for clinical application. On the other hand, the clinical guidelines for adhesive restorations have been released and updated accordingly, which would prolong the longevity of restorations. In this commentary, the removal of carious tissues, interface preparation for bonding and application of adhesives are emphasized. The administrative measures for registration and clinical evaluation criteria for adhesive restorative material are also introduced.

OCT for early quality evaluation of tooth-composite bond in clinical trials.

OBJECTIVES: To evaluate early quality of composite restorations with a universal adhesive in different application modes clinically and with optical coherence tomography (OCT). METHODS: 22 patients with four non-carious cervical lesions each received composite restorations (Filtek Supreme™ XTE, 3 M). The universal adhesive Scotchbond Universal™(SBU, 3 M) was applied with three etching protocols: self-etch (SE), selective-enamel-etch (SEE) and etch-and-rinse (ER). The etch-and-rinse adhesive OptiBond™ FL (OFL, Kerr) served as a control. Restorations were imaged by OCT (Thorlabs) directly after application (t0). After 14 days (t1) and 6 month (t2) OCT imaging (interfacial adhesive defects) was repeated combined with clinical assessment (FDI criteria). Groups were compared by Friedman-/Wilcoxon- and McNemar-Test. RESULTS: No differences were seen clinically between groups (pi ≥ 0.500). OCT assessment revealed more adhesive defects at the enamel interface with SBU/SE at t0-t2 compared to all groups (pi ≤ 0.016). OFL showed more defects than SBU/ER (t1: p = 0.01; t2: p = 0.083). At dentin/cementum interface OFL exhibited more adhesive defects than SBU with all conditioning modes (t0, t1, pi ≤ 0.003) and at t2 to SBU/SE and SBU/ER (p < 0.001). Since t1 defects with SBU were detected more frequently in the SE and SEE modes compared to ER (pi ≤ 0.037). In contrast to SBU defects increased with OFL up to t2 (pi ≤ 0.007). CONCLUSIONS: In contrast to clinical evaluation, OCT revealed subtle adhesive defects directly after application that might interfere with clinical success. It was demonstrated that ER does not decrease initial adhesion of SBU to dentin.

Polymerization shrinkage stresses in different restorative techniques for non-carious cervical lesions.

OBJECTIVE: This study evaluated the effect of different restorative techniques for non-carious cervical lesions (NCCL) on polymerization shrinkage stress of resins using three-dimensional (3D) finite element analysis (FEA). METHODS: 3D-models of a maxillary premolar with a NCCL restored with different filling techniques (bulk filling and incremental) were generated to be compared by nonlinear FEA. The bulk filling technique was used for groups B (NCCL restored with Filtek™ Bulk Fill) and C (Filtek™ Z350 XT). The incremental technique was subdivided according to mode of application: P (2 parallel increments of the Filtek™ Z350 XT), OI (2 oblique increments of the Filtek™ Z350 XT, with incisal first), OIV (2 oblique increments of the Filtek™ Z350 XT, with incisal first and increments with the same volume), OG (2 oblique increments of the Filtek™ Z350 XT, with gingival first) and OGV (2 oblique increments of the Filtek™ Z350 XT, with gingival first and increments with the same volume), resulting in 7 models. All materials were considered isotropic, elastic and linear. The results were expressed in maximum principal stress (MPS). RESULTS: The tension stress distribution was influenced by the restorative technique. The lowest stress concentration occurred in group B followed by OG, OGV, OI, OIV, P and C; the incisal interface was more affected than the gingival. CONCLUSION: The restoration of NCCLs with bulk fill composite resulted in lower shrinkage stress in the gingival and incisal areas, followed by incremental techniques with the initial increment placed on the gingival wall. CLINICAL SIGNIFICANCE: The non-carious cervical lesions (NCCLs) restored with bulk fill composite have a more favorable biomechanical behavior.

Color Compatibility of Gingival Shade Guides and Gingiva-Colored Dental Materials with Healthy Human Gingiva.

The CIELab and CIEDE2000 coverage error (ΔE*COV and ΔE'COV, respectively) of basic shades of different gingival shade guides and gingiva-colored restorative dental materials (n = 5) was calculated as compared to a previously compiled database on healthy human gingiva. Data were analyzed using analysis of variance with Tukey-Kramer multiple-comparison test (P < .05). A 50:50% acceptability threshold of 4.6 for ΔE* and 4.1 for ΔE' was used to interpret the results. ΔE*COV / ΔE'COV ranged from 4.4/3.5 to 8.6/6.9. The majority of gingival shade guides and gingiva-colored restorative materials exhibited statistically significant coverage errors above the 50:50% acceptability threshold and uneven shade distribution.

Dental Shade Guide Variability for Hues B, C, and D Using Cross-Polarized Photography.

This study evaluated the color variability of hues B, C, and D between the VITA Classical shade guide (Vita Zahnfabrik) and four other VITA-coded ceramic shade guides using a digital camera (Canon EOS 60D) and computer software (Adobe Photoshop CC). A cross-polarizing filter was used to standardize external light sources influencing color match. A total of 275 pictures were taken, 5 per shade tab, for 11 shades (B1, B2, B3, B4, C1, C2, C3, C4, D2, D3, and D4), from the following shade guides: VITA Classical (control); IPS e.max Ceram (Ivoclar Vivadent); IPS d.SIGN (Ivoclar Vivadent); Initial ZI (GC); and Creation CC (Creation Willi Geller). Pictures were evaluated using Adobe Photoshop CC for standardization of hue, chroma, and value between shade tabs. The VITA-coded shade guides evaluated here showed an overall unmatched shade in all their tabs when compared to the control, suggesting that shade selection should be made with the corresponding manufacturer guide of the ceramic intended for the final restoration.

Higher experience of caries and lower income trajectory influence the quality of restorations: A multilevel analysis in a birth cohort.

OBJECTIVES: This study aimed to evaluate the quality of posterior restorations (amalgam or composite) placed in adults from a birth cohort and its association with clinical and socioeconomic determinants experienced during their life course. METHODS: A representative sample (n=539) of all 5914 births occurring in Pelotas (Brazil) in 1982 was prospectively investigated. Quality of posterior restorations (satisfactory or unsatisfactory) was assessed at 31 yrs-old, using modified USPHS criteria. Trained and calibrated dentists performed clinical examination. Explanatory variables included demographic and socioeconomic, oral health and dental service utilization patterns during the life course. Tooth related variables (type of tooth, material, size of cavity) were also analyzed. Untreated caries and socioeconomic status were assessed by group-based trajectories analyses. Multilevel Regression models were used to determine factors associated with restoration outcomes. RESULTS: In total 2123 restorations (53% composite) were evaluated of which 107 (5%) were assessed as failed. The main reasons for failure were tooth/restoration fracture (50.5%) and secondary caries (30.7%). Failures in posterior restorations showed a significant association with socioeconomic aspects (lower tertile of income at age 30 - prevalence ratio (PR) 2.21 [95% CI 1.19-4.09]), clinical variables (trajectory of higher untreated caries - PR 2.11 [95% CI 1.23-3.61]) and also with tooth-related factors (Restorations involving three or more surfaces - PR 5.51 [95% CI 3.30-9.19]) after adjustment for each other. CONCLUSIONS: These findings suggest that, although tooth-related variables have an important role in restoration longevity, patient-related factors, such as socioeconomic variables and untreated caries are also associated with failure and should be taken into account when evaluating longevity of posterior restorations. CLINICAL SIGNIFICANCE: This was the first study assessing long-term trajectory of untreated caries, showing an association between higher experience of caries during the life-course and unsatisfactory restorations. The findings suggest that individual related factors should be considered when planning treatment and in future research evaluating the longevity of dental restorations.

Comparison of dimensional accuracy of conventionally and digitally manufactured intracoronal restorations.

STATEMENT OF PROBLEM: Advances have been made in digital dentistry for the fabrication of dental prostheses, but evidence regarding the efficacy of digital techniques for the fabrication of intracoronal restorations is lacking. PURPOSE: The purpose of this in vitro study was to compare the dimensional accuracy of intracoronal restorations fabricated with digital and conventional techniques. MATERIAL AND METHODS: A sound mandibular molar tooth received a standard onlay preparation, and onlays were fabricated with 1 of 3 fabrication techniques. In group CC, the onlays were made after conventional impression and conventional fabrication of a resin pattern. In group CP, the onlays were made after conventional impression and 3-dimensional (3D) printing of the pattern. In group IP, the onlays were made after intraoral scanning, and 3D printing produced the resin pattern. Ten specimens in each group (N=30) were evaluated. Glass-ceramic restorations were fabricated using the press technique. The replica technique was used to assess the marginal fit. Each replica was assessed at 8 points. One-way ANOVA was used to compare the marginal discrepancy among the 3 groups. The Tukey honest significant differences test was applied for pairwise comparisons of the groups (α=.05). RESULTS: No significant differences were noted in the marginal discrepancy at the gingival margin among the 3 groups (P=.342), but significant differences were noted among the 3 groups in the pulpal (P=.025) and lingual (P=.031) areas. Comparison of the absolute discrepancy among the 3 groups revealed that only groups CC and CP were significantly different (P=.020) from each other. CONCLUSIONS: Within the limitations of this in vitro study, the conventional method yielded more accuracy than the 3D printing method, and no differences were found between the methods which used the 3D printer (groups CP and IP).