Impression Technique Research Articles

Evaluation of the relationship between dermatoglyphics and mandibular third molar impaction: A cross-sectional study.

Background: Dermatoglyphics can be utilised in clinical settings to identify those who are more likely to have impacted teeth. Additionally, dermatoglyphics looks to have potential as a non-invasive diagnostic method for predicting the presence or absence of an impacted tooth. The goal of this study was to look at the most common dermatoglyphic pattern in people who had or didn't have an impacted mandibular third molar teeth and see if there was a dermatoglyphic signature. Methods: A cross-sectional study with 180 participants was conducted (90 cases and 90 controls). The rolling impression technique was used to apply blue duplicating ink to participants' fingertips, which was then recorded. There was an increase in the frequency of the whorl-plain pattern in the right-hand ring finger (60%; p=0.028) and left-hand little finger (33.3%; p=0.009), as well as the loop-ulnar pattern in the right-hand middle finger (74.4%; p=0.024) in individuals with a predisposition to the presence of impacted teeth. Results: The left-hand little finger was found to be the most predictive for impaction in a forward stepwise binary logistic regression analysis. Conclusions: Dermatoglyphics could be used as a non-invasive sign to predict whether or not a tooth is affected. Its value comes in early detection, which helps to avoid the surgical problems that come with symptomatic extraction of an impacted tooth.

EVALUATION OF DERMATOGLYPHIC PATTERNS AND THEIR CORRELATION WITH SKELETAL MALOCCLUSIONS

Background and Objectives: Dermatoglyphics deals with the study of the epidermal ridges and their congurations on the ngers, palms and soles. Epidermal ridge patterns form early in fetal development and remain unchanged throughout life and play a signicant role in the diagnosis of many disorders with genetic background. As the primary palate, lip and dermal ridges develop during the same period of intrauterine life, the genetic message contained in the genome - normal or abnormal, is deciphered during this period and is also reected by dermatoglyphics. The present study was undertaken to evaluate the different dermatoglyphic patterns and their correlation with skeletal malocclusions. The study was conducted on 90 individuals divided into 3 equal groups- skeletal Methods: class I, II and III. Dermatoglyphic patterns were recorded using ink method following rolling impression technique. The dermatoglyphic data was assessed for different nger ridge patterns and total ridge count (TRC). On compar Results: ison skeletal class I group showed markedly decreased number of loops and increased total ridge count (TRC). Skeletal class II showed markedly increased number of loops and markedly decreased TRC. Skeletal class III showed markedly decreased number of arches and increased TRC. Loops were found to be the most predominant pattern in skeletal class II and III groups. The mean TRC was found to be increased in skeletal class III group and markedly decreased in skeletal class II group which was statistically signicant. Dermatoglyphics can be used as a screening tool and for early prediction of skeletal mal Conclusion: occlusion at a younger age group. Dermatoglyphics have important practical and clinical implications which can be applied for preventive and interceptive orthodontics among paediatric patients and also for parent counseling.

Accuracy of Impression Techniques for Dental Implants Placed in Five Different Orientations.

The purpose of this study was to evaluate the impression accuracy of two implants placed in different orientations and compare the impression accuracy obtained with the dual-arch impression technique using hybrid impression copings and the conventional open-tray impression technique. Five mandibular dentiform models were prepared by placing implants in the second premolar and second molar regions in the following different orientations: parallel to each other; 15-degree mesiodistal angulation; 30-degree mesiodistal angulation; 15-degree buccolingual angulation; and 30-degree buccolingual angulation. After making 10 impressions for each model with the open-tray impression technique and dual-arch impression technique with hybrid impression copings, cast models were fabricated for each impression (n = 10). Scan bodies were mounted on the five dentiform models and the fabricated 100 cast models were scanned using a desktop scanner. The three-dimensional deviation of the scan bodies on the cast models was calculated and compared to the reference data from the dentiform models. A two-way analysis of variance was conducted (α = .05). The root mean square deviation values obtained from the implants placed with 30-degree mesiodistal angulation were 93.05 ± 6.21 μm with the open-tray impression technique and 104.01 ± 8.89 μm with the dual-arch impression technique, which were the largest deviation values for both techniques (P < .001). Compared to the open-tray impression technique, the dual-arch impression technique with the hybrid impression copings showed significantly lower accuracy when the angulation between the implants was 15 degrees mesiodistally (P < .001), 30 degrees mesiodistally (P = .016), or 30 degrees buccolingually (P < .001). However, there was no significant difference between the accuracy of the two impression techniques for parallel implants (P = .74). When the two implants were inclined 30 degrees mesiodistally, both implant impression techniques showed the largest deviation and the dual-arch impression technique showed lower accuracy compared to the conventional open-tray impression technique. Parallel placement of implants may improve impression accuracy and enable use of the dual-arch impression technique.

A survey of impression materials and techniques in fixed partial dentures among general dental practitioners and prosthodontists in India

Background: Replacement of missing tooth plays an important role in patient’s comfort and self-esteem. Aims and Objectives: The aims of this study were to investigate the most commonly used impression materials and techniques practiced for crowns and bridgework by prosthodontists and general dental practitioners compared to the theoretical methods suggested in the literature and to determine the clinical factors that might influence the decision-making process for the selection of impression materials and techniques. Materials and Methods: Pre-tested and pre-validated structured and closed-ended anonymous questionnaire was shared with general dental practitioners and prosthodontists. Results: Most of the prosthodontists use diagnostic impression compared to general dental practitioners (P&lt;0.01). Full-arch tray was used by general dental practitioners significantly more frequently compared to prosthodontists (P&lt;0.01) for single anterior, single posterior, anterior, and posterior bridge preparations. Alginate hydrocolloid was used by general dental practitioners significantly more than prosthodontists (P&lt;0.05); however, addition silicone and condensation silicone were used by prosthodontists significantly more than general dental practitioners (P&lt;0.05). For the impression technique followed in case of using elastomeric impression materials, the prosthodontists used the two-step putty reline technique with spacer more commonly, while general dental practitioners used the multiple mix technique (P&lt;0.01). For the use of provisional restoration for single tooth crowns and for all the bridges, prosthodontists used provisional restoration in significantly higher proportion as compared to general dental practitioners (P&lt;0.01). Conclusion: According to our study compared to general dental practitioners, practices of the prosthodontists regarding use of fixed partial denture is more in line with the current global trend.

Campagna Technique: A Boon for Debilitated Dentition Patients

Immediate complete denture insertion followed by removal of teeth provides a positive emotional response to the patient by saving the embarrassment of being edentulous and minimal alteration in general appearance, muscle tone, and speech. The patient gets adjusted to the change more quickly; the healing period is faster and less painful. However, the fabrication of immediate denture requires different impression techniques to follow than routine conventional complete denture procedure. This case report presents the fabrication of conventional immediate denture using Campagna impression technique which appears to be more precise among all the techniques as it ensures a similar degree of accuracy of the borders in the dentulous as well as edentulous region of the maxillary dental arch. To provide optimum benefit from the constructed denture, a lingualized balanced occlusal scheme was given.

Management of a complete denture in the flat mandibular ridge using a semi-adjustable articulator along with an effective suction method

Background: Complete dentures can improve the quality of life of edentulous patients. The selection of a suitable articulator and an impression technique is important to construct a stable and retentive complete denture with good occlusion. The use of a semiadjustable articulator ensures that the dentures can be constructed such that their movement closely resembles the patient’s physiological movements. The effective suction method can ensure the development of the border seal according to the patient’s anatomical condition. The use of a semi-adjustable articulator along with an effective suction method is expected to provide good results in the construction of a complete denture. Purpose: This report aimed to describe the management of individual complete dentures in the flat mandibular ridge using a semi-adjustable articulator along with an effective suction method. Case: A 69-year-old female patient came with a chief complaint of her old dentures being unusable and wanted new dentures made. The patient’s general condition was good, and the last extraction was done three months prior to the patient’s arrival. The mandibular posterior alveolar ridge showed dextral tapering and sinistral flatness. Case Management: A complete denture with an acrylic base was fabricated using a semi-adjustable articulator along with an effective suction method. Conclusion: Flat ridge case management using a semi-adjustable articulator with an effective suction method can improve complete denture retention and stability.

Prosthetic management of resorbed ridges through fabrication of hollow denture using three-dimensional glycerin spacer and neutral zone technique

Residual ridge resorption leads to diminished retention, support, and stability of the prosthesis due to decrease in the denture supporting areas, decreased denture space, and increased leverage due to increase inter-ridge distance. The prosthetic rehabilitation of the severely resorbed ridges needs modification for the fabrication of a stable prosthesis. This clinical report describes the prosthetic management of resorbed ridges using modified impression technique, neutral zone technique, external impressions, and fabrication of a hollow denture using three-dimensional glycerin spacer to enhance the retention and stability of the prosthesis.

Evaluating the accuracy of intraoral direct digital impressions in 2 infants with unilateral cleft lip and palate compared with digitized conventional impression

Presurgical infant orthopedics was introduced as an interceptive approach for treating cleft lip and/or palate (CLP). This study aimed to evaluate the intraoral digital impression technique as a viable alternative to conventional impression in infants with unilateral CLP. Trios 3-Shape scanner (3Shape, Copenhagen, Denmark) was used for intraoral scanning of the infants' maxillary arches to provide a direct digital scan (DDS). In addition, conventional impressions of the same patients were taken in a hospital setting, and the resultant stone models were digitized using the same scanner to create an indirect digital scan (IDS). Both scans (DDS and IDS) were exported in stereolithography format, and the resultant stereolithography files were imported into computer-assisted-design software (Exocad DentalCAD; exocad GmbH, Darmstadt, Germany) for 3-dimensional surface model superimposition. Differences between the 2 surfaces were quantified in millimeters and visually displayed by a color map. Three-dimensional surface model superimposition of the DDS and IDS scans showed an excellent agreement between both approaches, in which differences ranged from 0.01 mm to 0.1 mm CONCLUSIONS: Intraoral direct digital impression in infants with unilateral CLP is a safe, accurate, and time-efficient technique, which can be a viable alternative to conventional impression. This will aid in overcoming the challenges and complications that are frequently associated with using conventional impressions in infants with unilateral CLP, thus reducing the burden of care not only on the patients' families but also on the care providers.

Effect of full arch two scanning techniques on the accuracy of overdenture conventional and CAD/CAM Co-Cr bars

PurposeThis work evaluates the internal and marginal adaptation of implant-assisted overdenture cobalt–chromium (Co–Cr) bars manufactured using conventional as well as CAD/CAM subtractive and selective laser melting (SLM) utilizing two scanning techniques. Methods: An edentulous study model containing four dental implants placed at teeth sites 36, 33, 43, and 46 was used. The study cast was scanned and compared to the virtual casts developed from two scanning techniques, straight and zigzag motion, using the in silico superimposition process. Then, conventional techniques were used to produce full-arch bars that were compared to the bars fabricated using the two scanning techniques and CAD/CAM subtractive and additive techniques. Results: The conventional impression and casting techniques had the smallest marginal gap among the groups (P-value < 0.05). The CAD/CAM subtractive milling techniques in groups II and III had significantly smaller marginal gaps than SLM technique used in groups IV and V (P-value < 0.05). The analysis of the internal gap within each group showed statistically significant differences between different implant sites in all groups (P-value < 0.001), except when using the conventional impression and casting techniques in group I (P-value = 0.20). Conclusion: The conventional impression and fabrication techniques were better than the digital impression and CAD/CAM subtractive and additive techniques for the fabrication of full-arch bars. However, both straight and zigzag scanning techniques and the CAD/CAM subtractive technique had marginal and internal gaps that were within clinically accepted ranges, and the SLM was found to be unsuitable for long-span framework fabrication with either scanning technique used.

PROSTHODONTIC MANAGEMENT OF KNIFE-EDGE RIDGE USING CUSTOMIZED PREFABRICATED METAL MESH CUSTOM TRAY IMPRESSION TECHNIQUE

Knife-edge ridge is a form of an alveolar ridge primarily caused by lateral resorption i.e. bone resorption on the buccal as well as lingual areas at a faster pace. It is usually a common clinical finding affecting the mandibular edentulous ridges; in particular, the mandibular anterior region. It can be attributed to a number of reasons i.e. the etiology is similar to the multifactorial etiology of the residual ridge resorption. The treatment options or management of knife- edge ridge generally includes a surgical and a non-surgical approach. The non-surgical approach involves the fabrication of conventional removable dentures using various modified impression materials &amp; techniques. Prosthetic management of the patients with knife-edge ridge is a testing situation for the prosthodontist. The basic principles of retention, support, and stability are important in defining the success of a complete denture; the same can be affected in unconventional situations like knife-edge ridge. The incorporation of the conventional impression techniques may lead to an unstable and an unsatisfactory denture. Therefore, various impression materials &amp; techniques have been proposed in literature to overcome such issues. This case report portrays an innovative and practical yet simple modified impression technique utilizing the incorporation of a customized prefabricated metal mesh into the custom tray i.e. single step impression technique using polyvinyl siloxane as the impression material of choice for managing the knife-edge ridge situation in the mandibular arch and ultimately ensuring a well-fitting prosthesis.

An Indirect Digital Technique to Transfer 3D Printed Casts to a Mechanical Articulator With Individual Sagittal Condylar Inclination Settings Using CBCT and Intraoral Scans.

With the widespread application of digital impression techniques in prosthetic dentistry, accurate intraoral scan mounting, and virtual articulator parameters setting as per patients' anatomic structures are essential for treatment planning and restoration fabrication, especially for complex rehabilitation cases; meanwhile, marginal fit checking, occlusal adjustment, and porcelain layering of restorations are also crucial procedures in all cases in which the analog procedure to mount maxillary arches on a mechanical articulator is still required. This technique article presents an indirect digital approach that can first achieve virtual intraoral scan mounting and sagittal condylar inclination value setting of an Artex virtual articulator based on bony structures provided by a single cone beam computed tomography scan. It then facilitates the transfer of virtually mounted intraoral scans from the virtual articulator to the matched Artex mechanical articulator by relating a digitally scanned mounting plate of the Artex mechanical articulator to the virtual articulator, printing the intraoral scan and mounting plate scan assembly, and then mounting the printed casts on the mechanical articulator based on the printed mounting plate. This technique eliminates the conventional facebow transfer and protrusive bite registration procedures and offers a straightforward approach for the seamless integration of virtual environments and analog workflows into clinical practice. It aids in the design of restorations that are harmonious with the mandibular movements and reduces chairside adjustment time.

Accuracy of digital auricular impression using intraoral scanner versus conventional impression technique for ear rehabilitation: A controlled clinical trial

PurposeThis research aims to compare the accuracy of different auricular impression techniques used to produce either a mirror image of the unaffected ear or a surgical stent and template for auricular rehabilitation. The research compares two digital ear impression techniques using an Intra-Oral digital Scanner (IOS) (with /without markers) versus a traditional technique using hydrocolloid impression materials. Material and methodsEight participants were selected with intact right ears. Patients’ right ears were digitally scanned with an IOS, once with resin markers and once without markers. A conventional auricular impression was taken for each participant, which was then scanned using a desktop scanner. The digital IOS technique with markers was set as a reference model. Total 3D deviations between the study groups were calculated using Geomagic control software (software for 3D coordinate measuring technology). An independent sample t-test was used to make comparisons between the two tested groups. ResultsThe conventional impression and the intraoral scan without markers recorded a mean of 1.4057 ± 0.3581 and 0.7605±0.1469, respectively, of total 3D deviation from the intraoral scan with markers. There was a significant difference in auricular impression accuracy between conventional and intraoral scans without markers. ConclusionsUsing intraoral scanners facilitates impression acquisition and increases the accuracy compared to traditional hydrocolloid impression techniques, which may affect the shape of tissue due to its liability to be compressed by the impression material.Using markers allows for very precise data collection, reducing stitching complications that affect the accuracy of scans taken without markers. Clinical SignificanceThe proposed technique for auricular digital impression using an intraoral scanner guarantees a fast technique with accurate results in acquiring anatomical data for the rehabilitation of ear defects.This research was registered on clinicaltrials.gov with the following registration number: NCT04893902.

Vertical marginal gap evaluation of PEEK and Zirconia crowns using extra-oral scanner and CAD/CAM systems (An Invitro study).

Background and objective: Selecting a material with lower marginal gap is the key factor for a successful dental prosthesis. With less marginal gap of the crown the aggregation of bacterial plaque at the gingival margins, that result in periodontal diseases and secondary caries could be limited. Methods: A mandibular right first molar of a sound tooth was prepared for the reference model according to the tooth preparations guideline with a heavy chamfer finishing line for full zirconia and Polyetheretherketone (PEEK) coverage. Digital impression technique with extraoral scanner was used for scanning and taking impression of the reference model, ten crowns in each group were designed and milled using CAD/CAM systems. The vertical marginal gap between the crown's margin and the finishing line was measured for each crown on the reference model with the aid of a stereomicroscope in 160x. Results: The average (mean) for the marginal gap of proximal, buccal and lingual surfaces of both PEEK, and zirconia materials were: 409.097 μm, 112.869 μm, 198.563 μm, for PEEK and, 105.085 μm, 27.659 μm, 45.135 μm for zirconia respectively. Statistical analysis using t-test for two independent samples revealed that PEEK material showed a significantly higher marginal gap than z. irconia material. Conclusion: PEEK crowns had a higher marginal gap than clinically acceptable limit, while zirconia crowns exhibited much lower measurements.

Analysis of accuracy of two different implant impression techniques

Background: Comparatively evaluate the accuracy of two different implant impression techniques. Materials &amp; methods: For the present study, reference models used were an edentulous mandibular cast with four implant analogues in the anterior region and a metallic insert in the posterior. Two impression techniques were studied as followed: Group 1: Polyvinyl siloxane impressions (putty and light body) using stock metal tray, and Group 2: Polyether impressions (medium body) using stock metal tray. Connection of the impression posts was done to implant analogues with the screws tightened manually such that their flat surfaces were facing buccally. The longer impression posts were connected to the anterior analogues and shorter were connected to the posterior analogues. A self-calibration test was performed to determine the accuracy obtained by the single evaluator. Results: Mean error among the specimens of Group 1 was 0.0441 while mean error among the specimens of Group 2 was 0.0425 respectively. While comparing the mean error among the two study groups, non-significant results were obtained. Conclusion: From the above results, the authors concluded that both the impression techniques can be used with equal effectiveness in implant procedures.

Scanning accuracy with splinted and unsplinted implant scan bodies for the edentulous arch atimplant level: an in vitro study.

Accuracy of completely edentulous arch scanning with implant scan bodies has not been completely validated for intraoral scanners. For desktop laboratory scanners validations were found in the literature. The aim of this in vitro study was to compare the dimensional accuracy of scanning with splinted and unsplinted scan bodies on a completely edentulous maxillary arch with 6 implants. A maxillary edentulous master cast with 6 implants was used as control for all implant level impressions. 6 implants were digitally planned and placed at different angulation of 0, 0 17° and 30°. A contact coordinate measuring machine (CMM) was used to generate baseline linear measurements of the master cast. Four test groups included: 2 intraoral scanners Trios (3shape, Copenhagen, Denmark) and True Definition (3M ESPE, St Paul, MN), one industrial scanner Atos (Core optical 3D scanner) and one conventional impression group scanned with laboratory scanner Dental Wings 7 Series. Each scan recording was made with splinted and unsplinted scan bodies. Digital datasets of all measurements were compared with the CMM baseline values using PolyWorks® InnovMetric Software in order to assess the linear and angular deviations and determine the accuracy of complete arch digital impression. Factorial ANOVA showed significant effect with splinting, scanner type, inter-implant distance and implant angulation for linear deviations. Splinted scan bodies revealed elevated linear and angular deviation values for all scanners with significantly highest deviations for True Definition scanner. Significant correlation was found between inter-implant distance and linear deviation (r =0.45, P =<0.001) with increased linear deviations among all scanners, regardless of splinting. ( P <0.05). Significant effect on accuracy was seen for angular deviation with splinting, scanner type and implant angulation; significant difference was found between 0° and 30° implant angulation ( P =0.035) with more deviation with 30° implant angulation. The accuracy of the complete arch implant digital impression using splinted scan bodies was significantly reduced for measurements that crossed the arch midline. The digital impression technique using a broad splint design to connect scan bodies was not found to improve the scan accuracy for intraoral scanners.

Digital versus conventional full-arch impressions in linear and 3D accuracy: a systematic review and meta-analysis of in vivo studies.

The purpose of this systematic review was to compare the accuracy of digital and conventional full-arch impressions in vivo. This systematic review was conducted according to the PRISMA and registered at the PROSPERO (CRD42021232736). Electronic and hand searches were performed to identify in vivo studies comparing the linear or 3D accuracy of digital and conventional impressions. The risk of bias (ROB) of included studies was assessed by QUADAS-2, and the overall quality of evidence was assessed by GRADE. Twenty-two studies met the inclusion criteria, and 13 studies were included in the meta-analysis. There was no significant difference between digital and conventional impressions in the linear measurements of tooth width, anterior Bolton ratio, overall Bolton ratio, intercanine distance (ICD), and intermolar distance (IMD). The repeated measurement mean errors (RMEs) were less than 0.1 mm, the intra-examiner intraclass correlation coefficient (ICC) values were more than 0.9, and the inter-examiner ICC values were more than 0.87 for both impression techniques. The 3D deviation between digital and alginate impressions was 0.09 mm. The 3D precision of both impression techniques was less than 0.1 mm. The trueness of digital and alginate full-arch impressions was similar, and both impression techniques showed high precision. More research was needed to compare digital impressions and other conventional impression materials. For patients with completely natural dentition, the digital impressions obtained directly from intraoral scanning can be considered a viable alternative to alginate impressions.

Comparison of Linear Dimensional Accuracy Between One Step and Two-step Impression Technique Using Polyvinyl Siloxane Impression Material

Objectives: This study compares the linear dimensional accuracy between one step and two-step impression techniques using polyvinyl siloxane impression material. Methodology: The Randomized controlled trial was done in the Department of Prosthodontics, FMH College of Medicine and Dentistry Lahore and Pakistan Council for Science and Industrial Research Lahore. All impression samples which fall under the inclusion criteria in the Department of Prosthodontics, FMH College of Medicine and Dentistry Lahore and Pakistan Council for Science and Industrial Research Lahore were included. Samples were divided into two groups, i.e., Group 1 (single-step technique) &amp; Group 2 (two-step technique). The impression's longitudinal length and inter-line distance were measured to assess the outcome i-e linear dimensional accuracy. Result: A total of 60 impression samples with polyvinyl siloxane impressions material were made. The linear dimensional accuracy in one step &amp; two-step impression technique was seen in 5 (8.33%) &amp; 13(21.66%) samples, respectively, (p=0.011). Conclusion: Compared to the one-step impression technique, the higher linear dimensional accuracy of the two-step impression technique uses polyvinyl siloxane impression material.

Alginate Substitute as a Promising Impression Material for Dental Implant Restorations: A Comparative In-vitro Study

Objective: To compare the accuracy of alginate substitute with polyvinyl siloxane (PVS) impression materials for both single and multiple implant restorations using open- and closed-tray techniques placed unilaterally in a partially edentulous maxillary Typodont model. Methods: Two maxillary typodont hard models, two impression materials and two impression techniques were used in this study. A total of 80 impressions were made for both models simulating clinical scenario for single and multiple implant restorations, 10 impressions for each subgroup. Accuracy was assessed by measuring three dimensions (Anteroposterior, cross arch and vertical) on stone models obtained from impressions of the typodont models. Each dimension was measured three times and the mean value was calculated. The data were analyzed using independent samples t-test and Mann- Whitney U Test. Results: In group 1 (single implant), significant differences were found only in the vertical dimension between alginate substitute and monophase PVS impression materials when using an open-tray technique (mean diff.= 0.17; P= 0.003), and between closed- and open-tray techniques when using alginate substitute impression material (mean diff.= -0.24; P= 0.008). In group 2 (multiple implants), significant differences were found only in the horizontal cross-arch and vertical dimensions between open and closed-tray techniques when using alginate substitute impression material (P= 0.049 and P≤ 0.01, respectively). Conclusion: The results obtained showed that the stone dies fabricated using monophase PVS and alginate substitute impression materials were comparable to those of the typodont models. Overall discrepancies of the monophase PVS were smaller than those of the alginate substitute but not statistically significant.

To Compare the Dimensional Accuracy of Casts Obtained from Different Impression Techniques in Implant Prosthodontics: An In-Vitro Study

Abstract Introduction Obtaining an appropriate impression of the implant position and surrounding soft and hard tissues is paramount to fabricating an esthetically and biologically functional definitive restoration. Materials and Methods An edentulous maxillary acrylic master model was chosen. Four dummy implants were drilled into this model from the first premolar to first premolar region at equal distance using a dental surveyor to ensure parallel placement of the implants. Ten samples, each made for open tray (Group A), closed tray direct (Group B), and closed tray indirect (Group C) techniques using polyvinylsiloxane, were poured in type IV dental stone and 30 samples were hence obtained. The linear distance between the four implants were measured using the profile projector for each of the cast. The data obtained were analyzed using ANOVA and Tukey's HSD test. Observation and Results Inter-implant and inter-abutment linear distances were measured (in mm) for the master model and the samples for 1 to 2, 2 to 3, 3 to 4, 1 to 3, 2 to 4, and 1 to 4, and the maximum deviation was found in Group B. Conclusion The dimensional accuracy of casts obtained from closed tray indirect impression technique was the highest with linear distance values closest to the implant master model followed by open tray, and the least accuracy was found for closed tray direct impression technique.

Environmental disclosures in the non-financial reporting of energy companies. Creating a reliable business image or impression management?

Purpose: The purpose of the article is to determine whether and what impression management techniques are used by Polish listed energy-sector companies in their non-financial reporting to possibly create not a true but an embellished image of their oper-ations. Methodology/approach: The research entailed examining the non-financial annual reports published (in Polish) by eight large, listed companies. Both quantitative content analysis, to determine the scope of environmental disclosures, and qualitative content analysis, which focused on the visual and narrative style, were applied. The word count method was also applied concerning the positive (good) and negative (bad) wording used in the reports. Our linguistic analysis took into account both the semantic and inflexion aspects of Polish idiomatic expressions. Findings: We found that the companies exploited various manipulation techniques, both in the visualisation and the narrative used in their non-financial reports. Perfect graphics, blameless narrative style, or dynamic text organisation are among the top positive aspects. At the other end of the scale are aspects such as excessive wording, unnecessary repetitions of various keywords, or the intentional omission of adverse vocabulary. While both sets of techniques are more likely to be applied by bigger enti-ties, smaller companies do not seem to care as much for such details. Research implications/limitations: This research provides a valuable contribution to a better understanding of how companies employ modern narrative-oriented infor-mation management techniques relating to readers’ perceptions of non-financial state-ments. This may lead to enhancing formal requirements concerning the quality of non-financial disclosure in corporate reporting. The research was limited to only eight (all) energy companies listed on the Warsaw Stock Exchange for the financial years 2017–2020. Thus, there is a need to investigate whether other listed companies use impres-sion management techniques in non-financial reporting. Originality/value: This article is the first publication to show how Polish large energy-sector joint-stock companies manage their environmental impression in non-financial reporting. The analysis extends the knowledge on creating a business operations image that is favourable to stakeholders by companies with a high environmental impact. This is of particular importance considering the non-financial reporting obligation that such entities have to meet as per Directive 2014/95/EU.