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Purpose: To describe a digital workflow for the management of the emergence profile and the restoration's finishing line on vertically prepared teeth using a digital data set. Materials and Methods: Three scans (the prepared teeth the day of the preparation, the provisional restoration placed on the preparation after soft tissue maturation, and the provisional restoration outside of the oral cavity) were combined under a common data set to provide the necessary information to design the final restoration. Results: The digital technique presented can facilitate the implementation of the vertical preparation, because the desired finish line can be defined by the clinician and be transferred predictably to the dental lab. The current approach provides an alternative gingival management method, taking advantage of the displacement of soft tissue after vertical preparation. Conclusions: Positioning of the final finishing line on vertically prepared teeth, management of soft tissue, and fabrication of the final restoration can be facilitated with this approach, combining a digital data set that has been obtained during a distinct phase of the treatment. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the influence of a single infrapositioned ankylosed tooth or implant-supported restoration on smile esthetics. Materials and Methods: A series of 48 digitally modified images that simulated varying degrees of infraposition (from 0.25 to 2.0 mm, with a step of 0.25 mm) were created for each maxillary anterior tooth by altering the full-portrait image of a smiling man, adjusted to show medium and high smile lines. For the model with the high smile line, a series of 24 digitally modified images were created that simulated the infraposition of a single anterior tooth with a restored incisal edge. Smile esthetics for each of the images were evaluated by 160 participants (80 dentists and 80 laypersons), and a visual analog scale (VAS) was implemented. Results: For the images with the high smile line, an infraposition of ≥ 0.25 mm in the central incisor region and ≥ 0.5 mm in the region of the lateral incisor or the canine had a negative effect on the perceived smile esthetics for both the dentists and the laypersons. Regarding the medium smile line, an infraposition of ≥ 0.5 mm in the central and lateral incisor region had a negative effect on the perceived smile esthetics for both groups of observers. In the canine area, an infraposition of ≥ 0.5 mm for the dentists and ≥ 0.75 mm for the laypersons also had a negative impact on the smile esthetics. Conclusions: Even a minor infraposition of a single maxillary anterior ankylosed tooth or implant-supported restoration can reduce the perceived attractiveness of the smile. Infraposition in the canine site can be better tolerated in a medium smile line compared to a high smile line. In patients with a high smile line, prosthetic intervention is needed to restore the incisal edge of an infrapositioned tooth without harmonizing the gingival contour; this can be beneficial for the lateral incisor but ineffective for the central incisor and unfavorable for the canine. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the dimensional stability over time of additively manufactured surgical templates, fabricated by different resins, and stored by different methods. Materials and Methods: Using a 3D printer with DLS technology and two different resins (Surgical Guide (SG)‐WhipMix and Key Guide (KG)‐KeystoneIndustries), 96 surgical guides were additively manufactured. The guides were stored in three different environments: directly exposed to sunlight (S1), in normal interior room conditions (S2), and in darkness (S3). The guides were digitally scanned immediately after fabrication and post‐processing, and after 1, 3, and 6 months of storage. For each group, the mean deviation of the root mean square (RMS) between guide's intaglio surface, as well as the axial deviation between sleeves' housings were calculated. Results: The mean axial variations of angular axis deviation of sleeves' housings ranged between 0.09° and 3.99°. The mean deviation of the RMS discrepancy in guide's intaglio ranged from 0.1 to 0.18 mm. Variations were significant (p < 0.001) only for the S1 group and only for SG material. After 3 months, an additional storage time of 3 months did not have any further effect on dimensional stability. Conclusions: Within the limitations of the present study, storage time of a surgical guide for up to 3 months after manufacturing, as well as printing material can significantly affect surgical guide's dimensional stability, when they are exposed to direct or indirect sunlight conditions. Storage of guides in a dark environment is recommended in order to avoid an additional source of error in computer‐guided surgery workflows. [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives Materials and Methods Results Conclusions To investigate the reliability and time efficiency of the conventional compared to the automatic artificial intelligence (AI) segmentation of the mandibular canal and registration of the CBCT with the model scan data, in relation to clinician's experience.Twenty clinicians, 10 with a moderate and 10 with a high experience in computer‐assisted implant planning, were asked to perform a bilateral localization of the mandibular canal, followed by a registration of the intraoral model scan with the CBCT. Subsequently, for each data set and each participant, the same operations were performed utilizing the AI tool. Statistical significance was assessed via a mixed model (using the PROC MIXED statement and the compound symmetry covariance structure).The mean time for the segmentation of the mandibular canals and the registration of the models was 4.75 (2.03)min for the manual and 2.03 (0.36) min for the AI‐automated operations (p < 0.001). The mean discrepancy in the mandibular canals was 0.71 (1.80) mm RMS error for the manual segmentation and 0.68 (0.36) RMS error for the AI‐assisted segmentation (p > 0.05). For the registration between the CBCT and the intraoral scans, the mean discrepancy was 0.45 (0.16) mm for the manual and 0.37 (0.07) mm for the AI‐assisted superimposition (p > 0.05).AI‐automated implant planning tools are feasible options that can lead to a similar or better accuracy compared to the conventional manual workflow, providing improved time efficiency for both experienced and less experienced users. Further research including a variety of software and data sets is required to be able to generalize the outcomes of the present study. [ABSTRACT FROM AUTHOR]

Objective: The aim of the present study was to provide recommendations in order to facilitate communication between dental professionals and surgeons who are collaborating in the field of dentofacial esthetics. Clinical Considerations: Smile esthetics are beyond the scope, both of the surgeons who are collaborating with facial esthetics and of the dentists, as a wide range of treatment options from both sides is available. It can be difficult for the surgeon or the dentist that first comes in contact with the patient to conduct an individualized global treatment plan, in order to find out how the various phases of the treatment can be sequenced, as a workflow for an efficient interaction between facial surgery and dentistry still does not exist in the scientific literature. Conclusions: Facial cosmetic procedures and dental treatment have to be planned as individual elements of the whole dentofacial esthetic rehabilitation. The treatment has to be initiated with the design of the smile and the intraoral mock‐up, followed by the required surgical interventions, and to be finished with the delivery of the definitive dental restoration. Clinical Significance: Dentofacial esthetics require comprehensive communication between surgeons and dentists. Following the proposed recommendations, an individualized interdisciplinary treatment plan can be conducted, defining the role of each specialty. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study is to investigate the outcomes of clinically relevant laboratory studies regarding the cementation of implant‐supported restorations over ti‐bases. Materials and Methods: The present study has been conducted according to PRISMA statement. An electronic search was performed, including publications up to March 2024, to identify studies investigating the parameters affecting the cementation between ti‐bases and CAD/CAM prostheses. An assessment of the internal validity was performed, using a custom‐made risk of bias tool (QUIN). Results: From the included studies, 40.1% were reported on luting systems, 25% on ti‐base surface treatment, 25% on restoration surface, 21.8% on restoration material, and 18.7% on ti‐base height. The majority of the included studies were associated with a medium risk of bias. In the absence of micro‐retentive features, air‐abrasion of ti‐bases with a minimum height of 3.5 mm can be beneficial for restoration's retention. The bonding performance can vary not only between different bonding systems but also for different applications within the same system, based on a restoration's material and surface treatment as well as on ti‐base height and surface treatment. Conclusions: The height of the ti‐base seems to be the prevailing factor as it constitutes the prerequisite for other modifications of the bonding surfaces to have an advantageous effect. Since the parameters that can affect bonding performance between ti‐base and restoration can interact with each other, it is important for the clinician to focus on verified bonding protocols. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the accuracy of conventional and automatic artificial intelligence (AI)‐based registration of cone‐beam computed tomography (CBCT) with intraoral scans and to evaluate the impact of user's experience, restoration artifact, number of missing teeth, and free‐ended edentulous area. Materials and Methods: Three initial registrations were performed for each of the 150 randomly selected patients, in an implant planning software: one from an experienced user, one from an inexperienced operator, and one from a randomly selected post‐graduate student of implant dentistry. Six more registrations were performed for each dataset by the experienced clinician: implementing a manual or an automatic refinement, selecting 3 small or 3 large in‐diameter surface areas and using multiple small or multiple large in‐diameter surface areas. Finally, an automatic AI‐driven registration was performed, using the AI tools that were integrated into the utilized implant planning software. The accuracy between each type of registration was measured using linear measurements between anatomical landmarks in metrology software. Results: Fully automatic‐based AI registration was not significantly different from the conventional methods tested for patients without restorations. In the presence of multiple restoration artifacts, user's experience was important for an accurate registration. Registrations' accuracy was affected by the number of free‐ended edentulous areas, but not by the absolute number of missing teeth (p <.0083). Conclusions: In the absence of imaging artifacts, automated AI‐based registration of CBCT data and model scan data can be as accurate as conventional superimposition methods. The number and size of selected superimposition areas should be individually chosen depending on each clinical situation. [ABSTRACT FROM AUTHOR]

Purpose: The objective of the present article was to evaluate the ımpact of dental midline angulation in asymmetrical faces. Materials and Methods: A full‐portrait image was used to create a set of digitally modified images with a different degree of facial asymmetry, towards the right and the left side of the face respectively. Half of the images were designed with an equivalent angulation of the dental midline in respect to the curve of the lower third of the face and half of them without. Through a web survey, 250 laypeople and 250 orthodontists were asked to assess the attractiveness of each image separately. Results: As the asymmetry of the face was increased, facial attractiveness was further decreased both for laypersons and orthodontists. For each one of the modified images, when the dental midline was following the curve that was formed from the inclination of the simulated asymmetry of the face, the smile attractiveness scores were significantly higher compared to a straight dental midline. Conclusion: Facial asymmetries derived from the inclination of the nose, the chin and the commissural line of the lips can significantly affect the smile attractiveness. An orientation of the dental midline towards the facial asymmetry in order to follow the facial curve, can be beneficial for the smile attractiveness compared to a perpendicular to the face dental midline. During the design of a smile, clinicians have to take into consideration deviations in facial midline, in order their restorations to be in harmony with the rest of the face. Clinical Significance: During the design of a smile, clinicians have to take into consideration deviations in the facial midline, in order their restorations to be in harmony with the rest of the face. [ABSTRACT FROM AUTHOR]

Objective: Despite the wide clinical use of translucent zirconia for full‐arch implant prostheses, reduced flexural strength and fracture toughness compared with high‐strength opaque zirconia needs to be addressed. A novel proof of concept for FP1 full‐arch prosthesis featured by translucent monolithic zirconia and titanium framework was presented. Clinical Considerations: Computer‐guided implant planning and surgery were executed and digitally designed FP1 temporary prosthesis prefabricated. Implant and prosthetic placement were achieved with a set of three‐dimensional (3D)‐printed templates. Implants were immediately loaded. After 4 months intraoral optical scan was taken to record implant coordinates, soft tissue anatomy, and temporary FP1 prosthesis. A novel digital workflow was used to design and mill overlaying translucent zirconia and anatomically shaped titanium framework with a scalloped soft‐tissue interface. Final FP1 prosthesis was assembled cementing zirconia jacket on titanium counterpart. Conclusions: Translucent zirconia supported by titanium framework can address esthetic and mechanical requirements of FP1 full‐arch prosthesis, minimizing risk of fracture and providing a rigid and passive joint with supporting implants. The smooth and highly polished titanium surface with an anatomic design, tightly matching scalloped soft tissue interface, can limit food impaction, air and saliva leakage and contribute to overall biologic integration of FP1 full‐arch prosthesis. Clinical Significance: Translucent monolithic zirconia featured with anatomically shaped titanium framework with scalloped transmucosal part, combining a pleasant esthetic outcome with increased flexural strength and fracture toughness, may be indicated to increase the clinical performance of FP1 full‐arch prosthesis. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Computerized Dentistry is the property of Quintessence Publishing Company Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: To describe a digital workflow utilizing 3D printing technology to guide esthetic crown lengthening and control tooth preparation. Clinical considerations: After the initial intraoral and face scans, an esthetic treatment plan was performed digitally based on the patient's personality and face type using artificial intelligence-based 3D smile design software. A 3D-printed tray relined with silicone over a 3D-printed model was used for the mock-up. A 3D-printed guide was implemented to assist esthetic crown lengthening by incorporating, simultaneously, information about the desired free gingival line and the alveolar bone level. Based on the initial planning, a set of reduction guides was 3D printed to check and correct the tooth preparation. Prior to the start of construction of the final monolithic restorations, their design was verified using 3D-printed prototypes. A stabilization splint was digitally designed and 3D printed to protect and maintain the final result. Conclusions: Technologic advances can improve the predictability of an interdisciplinary esthetic approach. Digital planning can be transferred to clinical reality using a digital workflow, utilizing a set of appropriate 3D-printed guides, which can help to control clinical procedures based on the initial planning. Clinical significance: By following the proposed step-by-step workflow, clinicians can achieve predictable results through an interdisciplinary approach, guiding both the periodontal plastic surgery and the restorative treatment after an individualized CAD/CAD procedure for 3D-printed guides. (Int J Esthet Dent 2023;18:330-344) [ABSTRACT FROM AUTHOR]

Purpose: To describe a technique utilizing a novel prosthetic scan body, that assists the accurate merging of multiple scans (intra- and extraoral) of the interim prosthesis and edentulous arch with dental implants, during rehabilitation with a fixed implant-supported prosthesis. Methods: Intraoral scanning (Trios 3, 3Shape) of an interim implant-supported prosthesis was performed, subsequently followed by another scan, using five scan bodies, placed onto the implant abutments (SRA, Bone level, Straumann AG). Successively, the newly designed prosthetic scan bodies were attached to the abutment copings of the interim prosthesis, for extraoral scanning. Utilizing an implant library designed for the prosthetic scan body, the three scans were merged, providing all the necessary information for the digital design and fabrication of the fixed implant-supported prosthesis. Conclusions: The described clinical technique enabled effective and accurate superimposition of intra- and extraoral scans of the implant prosthesis. Superimposed data, including that of the position of dental implants and anatomy of soft tissue, provided essential information for the fabrication of a definitive implant-supported prosthesis. The novel prosthetic scan bodies attached to the implant prosthesis, assisted in merging intra- and extraoral scans, thus facilitating the rehabilitation of maxillary and/or mandibular edentulous dental arches. Further research is required to assess the accuracy of the proposed technique. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the influence of lightness difference of a single anterior maxillary tooth on difference smile attractiveness. Methods: A frontal view full‐portrait image of a smiling male Caucasian, was digitally modified altering a single tooth, creating a series of images with varying lightness (ΔL) for the maxillary central, lateral and canine. A total of 160 participants (80 dentists, 80 laypersons) were asked to fill out a Visual Analog Scale questionnaire for every image recording smile attractiveness. Results: For central incisors ΔL≥1 negatively affected attractiveness. There was a higher tolerance for lightness mismatch when one lateral incisor is lighter and the same applies when the canine was darker. Difference in lightness affected smile attractiveness both for dentists and laypersons. No difference between males and females was observed for the dentists. For laypersons, females perceived smiles with lightness difference as significantly less attractive compared to males. Dentist's age did not affect smile attractiveness perception. Younger laypersons perceived darker color, as less attractive. Conclusions: Changes in lightness of a single anterior tooth significantly affected smile attractiveness in a different way for the central vs lateral vs canine. For the dentists, age and gender did not significantly affect smile perception, in contrast to laypeople. Clinical significance: Lightness differences of a single anterior tooth affects smile attractiveness. [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives Overview Conclusions Clinical Significance To classify the complete‐arch implant scanning techniques recorded by using intraoral scanners (IOSs).Different implant scanning techniques have been described for recording complete‐arch implant scans by using IOSs. However, dental literature lacks on a classification of these implant scanning techniques. Implant scanning techniques aim is to record the 3‐dimensional position of the implants being scanned, while implant scanning workflows require additional scans to record all the information needed for designing an implant prosthesis. This additional information includes soft tissue information, tooth position, antagonist arch, and maxillomandibular relationship.There are five complete‐arch implant scanning techniques captured by using IOSs: non‐splinting, non‐calibrated splinting, calibrated implant scan bodies, calibrated frameworks, and reverse impression methods. The digital workflow varies depending on the implant scanning technique selected.The understanding of the varying implant scanning techniques and the main differences among them may ease the decision criteria for recording digital implant scans by using intraoral scanners. [ABSTRACT FROM AUTHOR]

Statement of Problem: Digitized analog records have been used for the superimposition of intraoral and facial scans. However, the discrepancy in the registration between the digitized occlusal records contained on extraoral scan bodies and the maxillary virtual cast remains uncertain., Purpose: The purpose of this in vitro study was to evaluate the effect of the registration method, edentulous area, and tooth anatomy on the accuracy of the alignment between the digitized extraoral scan body (ESB) and the maxillary virtual cast., Material and Methods: A scannable ESB and a set of 8 maxillary casts (2 completely dentate simulating unworn and worn tooth anatomy, 5 partially edentulous, and 1 completely edentulous were printed (Pro 95S; SprintRay). Four zirconia markers were attached to the index of the ESB and each of the evaluated casts. Each cast was positioned into the tray of the ESB using occlusal registration material (O-Bite; DMG). The ESB and each corresponding evaluated cast were digitized by using a calibrated laboratory scanner (T710; Medit). Then, each cast and index of the ESB were scanned separately by using the same scanner (n=10). Using a CAD software program, each virtual cast was attached to the ESB 10 times by using 3 different alignment methods: an analog using an iterative closest points (ICP) algorithm and 2 semimanual alignments using a best-fit algorithm for the entire data set with or without including the edentulous areas. A metrology software program was used to measure the linear distance between the corresponding gauge balls and the angulation between the planes defined by the markers on the cast and the ESB. The measurements from the scans of the casts attached to the tray were used as a reference to calculate the discrepancies in each experimental group. Α P value threshold of <.05 was used to determine statistical significance., Results: The best-fit algorithm registration method produced better trueness and precision than the manual point-to-point registration (P<.05). When the edentulous areas were not included in the analog surface record, the trueness and precision of the best-fit algorithm were significantly worse (P<.05). In respect of tooth anatomy, no significant difference in trueness and precision was found among the investigated groups (P>.05). The completely dentate groups presented significantly better trueness than the edentulous groups (P<.05)., Conclusions: The accuracy of the registration between digitized occlusal surface scans and digital casts was influenced by the registration method, as well as by the location and extent of the edentulous areas., (Copyright © 2025 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

The accuracy of diagnostic trial restorations depends on the rigidity of the restoration index. However, as the index becomes stiffer, its removal from the mouth without the detachment of the underlying trial restoration can be challenging, especially in patients where a diagnostic trial restoration is required for a complete arch rehabilitation. The present manuscript describes a step-by-step hybrid technique to transfer the virtual diagnostic waxing into the patient's mouth by using a 2-piece index. An additively manufactured custom tray relined on a diagnostically waxed cast using polyvinyl siloxane material is used to fabricate a silicone index. The presented technique provides an index with higher rigidity and uniformity compared with conventional methods, enabling sequential removal after the polymerization of the resin interim material., (Copyright © 2025 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Statement of Problem: An implant scanning workflow involves recording different intraoral scans containing all the information needed to fabricate an implant-supported prosthesis. The accuracy of these implant scanning workflow registration methods remains unknown., Purpose: The purpose of this in vitro study was to compare the accuracy of different implant scanning workflows for registering the soft tissue and tooth position information scans recorded by using 5 intraoral scanners (IOSs)., Material and Methods: A maxillary edentulous stone cast with 6 implant abutment analogs (MultiUnit Abutment Replica) and 2 screw-retained implant-supported interim restorations (from the right first molar to the left canine and from the left first premolar to the left first molar) were obtained. Three markers were attached on the palatal surface of the cast on the anterior palatine raphe and right and left first molar positions, and 4 markers were attached on the palatal surface of the right and left second premolar and right and left lateral incisor of the interim prostheses. Afterwards, 5 composite resin (CR) reference landmarks were created on the palatal surface of the cast on the anterior palatine raphe, right and left first premolar, and right and left first molar. Additionally, a screw was placed in the posterior palatine raphe, simulating a temporary anchorage device (TAD). The interim prostheses were positioned in the implant analogs of the cast and digitized by using a laboratory scanner (T710). Five groups were created depending on the IOS: TRIOS 5, i700, Elite, iTero, and Primescan groups. A tooth position, soft tissue information, and soft tissue with existing teeth scans were obtained by using each IOS. Six subgroups were created depending on the reference landmarks used to register the scans: 3 or 5 CR landmarks (3CR or 5RC subgroup, respectively), existing teeth (teeth subgroup), existing teeth combined with 2 CR landmarks (teeth+2CR subgroup), TAD (TAD subgroup), TAD combined with 1 CR landmark (TAD+1CR subgroup). Twelve linear measurements were performed on the control scans and on each specimen among the 7 markers. Trueness was analyzed by using 2-way ANOVA and the pairwise comparison Tukey tests (α=.05). Precision was evaluated by using the Levene and pairwise comparisons tests (α=.05)., Results: Trueness discrepancies were found among the groups (P<.001) and subgroups (P<.001), with a significant group*subgroup interaction (P=.004). The Tukey test showed that the Primescan and iTero systems obtained worse trueness than the other groups. Also, the TAD and Teeth subgroups obtained worse trueness than the other subgroups tested. All the groups and subgroups were significantly different from each other (P<.05)., Conclusions: The IOS and reference landmarks tested impacted the trueness and precision of the registration of soft tissue and tooth position information scans., (Copyright © 2025 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Custom sports mouthguards are used in various sports to protect teeth, temporomandibular joints, and soft tissues from impact forces. The present article demonstrates a digital workflow to fabricate a 3-dimensionally (3D) printed individualized sports mouthguard. An optical jaw tracking system is used to record a repeatable reference position, and mandibular excursive movements to achieve a completely balanced occlusion. The technique simplifies the fabrication of a custom-fit mouthguard over the conventional approach by providing increased thickness accuracy, control of design, and integration of jaw motion., (Copyright © 2024 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess the survival and complication rates of 115 monolithic zirconia implant-supported fixed complete dental prostheses (IFCDPs) with an up to 6-year follow-up., Materials and Methods: One hundred fifteen edentulous jaws (71 patients) underwent complete-arch implant treatment with a digital workflow and were rehabilitated with monolithic zirconia IFCDPs. The primary outcome was to assess survival and complication rates while the secondary outcome was to measure the cross-sectional dimensions (prosthetic space) of those 115 monolithic zirconia IFCDPs and to correlate potential technical complications with the prosthetic space dimensions., Results: Out of the 115 zirconia IFCDPs, 2 fractured, yielding a 98.6% survival rate up to a 6-year follow-up. The most commom minor technical complications were loss of screw access channel filling and porcelain chipping for the modified monolithic IFCDPs. There was no significant association between the count and type of complications and jaw location (maxilla vs. mandible) or prosthesis type (FP1 vs. FP3), according to Fisher's exact test. For maxillary zirconia IFCDPs, the mean square surface for the at the posterior abutment cross-sectional area was 25.18 mm 2 at the lingual side of the abutment and 34.19 mm 2 at the buccal side, respectively. The anterior abutment cross-sectional area was 33.92 mm 2 at the lingual side of the abutment and 29.49 mm 2 at the buccal side, respectively. For mandibular zirconia IFCDPs, the mean square surface at the posterior abutment cross-sectional area was 29.89 mm 2 at the lingual side of the abutment and 39.05 mm 2 at the buccal side, respectively. The anterior abutment cross-sectional area was 27.07 mm 2 at the lingual side of the abutment and 56.50 mm 2 at the buccal side, respectively. At the connector cross-sectional area, the mean square surface for the maxillary zirconia IFCDPs was 64.33 and 90.56 mm 2 for the mandibular zirconia IFCDPs. The two fractures occurred in the midline (anterior area) for both maxillary FP1 prosthesis and mandibular FP3 prosthesis. The mean surface area at the connector for the maxillary FP1 prosthesis was 28.50 and 82.11 mm 2 for the mandibular FP3 prosthesis, and was within the range of IFCDP connector square surface area. There was no significant association between the thickness of the zirconia prosthesis and the encountered prosthesis fractures., Conclusions: Monolithic zirconia IFCDPs yielded a 98.6% survival rate, after a mean observation period of 62 months with an SE of 3.1. The connector mean surface area in the two fractured IFCDPs was within the square surface range (minimum-maximum) as for the remaining 113 complication-free IFCDPs., (© 2024 by the American College of Prosthodontists.)

Statement of Problem: Intraoral scanners (IOSs) can be used to record the maxillomandibular relationship at centric relation (CR). The articulated digital scans can be imported into a dental computer-aided design (CAD) program and used to locate centric occlusion (CO); however, the accuracy of the CO recorded by using IOSs and a dental CAD program remains unknown., Purpose: The purpose of this clinical study was to compare the position of the CO located by using a conventional method and 4 IOSs combined with a dental CAD program., Material and Methods: A patient volunteered to participate in this study. Conventional diagnostic stone casts were obtained. A facebow record (Kois Dentofacial Analyzer) was used to transfer the maxillary cast into a semi-adjustable articulator (Panadent PCH Articulator). A Kois deprogrammer (KD) was used to record the maxillomandibular relationship at CR and to transfer the mandibular cast into the articulator. Afterwards, CO was located in the articulated casts by removing the incisal pin and using an 8-µm articulating foil. CO was marked in the casts by using a blue articulating paper (control). Three groups were created based on the IOS used: TRIOS 4, iTero Element 5D Plus, i700, and Primescan. In each IOS group, a maxillary and mandibular scan were obtained. The scans were duplicated 10 times. Afterwards, a bilateral occlusal record captured with the KD was used to articulate each pair of duplicated scans. Each articulated specimen was imported into a CAD program (DentalCAD) and CO was virtually located. The teeth contacting at the CO of each specimen were compared with the control group. Categorical data were analyzed by using the chi-squared test (α=.05)., Results: The chi-squared test revealed a significant association between the IOS system and the location of the CO (P=.004). The highest association was found between the TRIOS 4 and CO position, in which 100% of the specimens obtained the same CO position as in the conventional group. The lowest association was found between the i700 and CO position. In the i700 group, 20% of the specimens showed the same CO position as in the control group. A similar outcome was obtained in the iTero and Primescan groups. In both groups, 60% of the specimens demonstrated the same CO position as the control group., Conclusions: The IOS system used to acquire articulated scans at CR impacted the CO position located by using the evaluated digital methods. The TRIOS 4 system was the only IOS that consistently reproduced the same CO position as the conventional method., (Copyright © 2024 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine the effect of restorations with long contact areas for the management of interdental papilla deficiencies, in smile attractiveness among laypersons and dentists., Material and Methods: A full-portrait image was used to create a set of digitally modified images, simulating the management of various levels of interdental papilla loss. In a total of 48 modified images, single as well as multiple loss of interdental papilla among the anterior teeth, treated with a single or multiple restorations were simulated for unilateral and bilateral situations. Through a digital monitor 160 laypeople and dentists were asked to assess the attractiveness of each displayed image utilizing a visual-analog-scale. Multiple Wilcoxon-signed-rank tests followed by Mann-Whitney U tests were performed considering a significance level of 0.05., Results: The management of an open gingival embrasure due to interdental papilla loss, by simulating the restoration of both central incisors led to a significantly higher mean smile attractiveness compared to the restoration of a single central incisor. Among the investigated regions, the management of open gingival embrasure in the area of central incisors using a restorative approach was perceived as the least esthetic (p < 0.05)., Conclusions: Despite the restorative management of interdental papilla loss, with the establishment of longer contact areas for the reduction of open gingival embrasures, as the level of the interdental papilla loss is increased, facial esthetics are compromised. When a longer contact area is accomplished through a single restoration, asymmetry among the teeth can be induced, especially in the region of the central incisors., (© 2024 by the American College of Prosthodontists.)

Purpose: The aim of the present case report was to describe, through a clinical case, a step-by-step technique, for the digital selection of composite resin shades using cross polarization and white balance employing a standardized reference card., Case Description: After intraoral impression, a digital diagnostic wax up was developed. A 3D printed cast was used to fabricate a lingual polyvinyl siloxane matrix. First a cross-polarized image of the contralateral central incisor was taken in RAW format, using a gray reference card. The digital image was manipulated using this card as a reference, to obtain reliable color values. The obtained color values, from the contralateral central incisor, were used in order to digitally find the closest combination of enamel and dentin shades between various composite systems. The values of a combination of shades of composite systems, was captured using cross-polarized images, with a gray reference card, after digital image manipulation of composite specimens, which have been created for this purpose., Conclusions: Digital evaluation and selection of composite resin system and shade, using a white balance reference card assisted by cross polarized photography, could help achieving more predictable outcomes using the stratification technique with composites. Key words: Restoration shade, composite color, composite resin, direct restoration, digital protocol., Competing Interests: Conflicts of interest None declared., (Copyright: © 2021 Medicina Oral S.L.)

Introduction: Τo describe the clinicopathological features of 26 oral lymphoepithelial cysts (LECs) and review the literature., Material and Methods: Twenty-six cases of oral LECs diagnosed during a 37-year period were retrospectively collected. The patients' gender and age, as well as the main clinical features of the cysts were retrieved from the requisition forms. The main microscopic features were recorded after reevaluation of all cases. Pubmed and Google Scholar electronic databases were searched with the key word "oral LEC". Inclusion criteria were the microscopic confirmation of LEC diagnosis and the report at least two of three main clinical features (gender, age and cyst's location)., Results: The 26 oral LECs represented 0.08% of 31,564 biopsies accessioned during the study period. They affected 25 patients, 14 females and 11 males with a mean age of 33.04±9.81 years. They appeared as smooth (92%) nodules, with soft (24%) or firm (76%) consistency and normal (28%), yellow to normal (20%), yellow (32%) or white (20%) hue, in the tongue (69.23%) or the floor of mouth (30.77%). They were covered by parakeratinized squamous (92.31%) or non-keratinized (7.69%) epithelium and contained desquamated epithelial cells, amorphous eosinophilic material and/or inflammatory cells (100%). The lymphoid tissue surrounded the cystic cavity partially (34.62%) or completely (65.38%), often in a follicular pattern with prominent germinal centers (53.85%). Literature review yielded 316 cases of oral LECs derived from 25 case reports, 3 case studies/retrospective studies with detailed information for each case and 7 studies with summarized data., Conclusions: Oral LEC is a pathologic entity with discrete clinical presentation that is, however, commonly misdiagnosed in clinical practice as other, mostly benign, entities. Its pathogenesis remains obscure, as its clinicopathologic features are consistent with both theories suggested up to date. Key words: Oral lymphoepithelial cyst; developmental cyst; non odontogenic cyst; lymphoid tissue; oral tonsil., Competing Interests: Conflict of interest statement:None declared.