Accuracy of intraoral optical scan versus stereophotogrammetry for complete-arch digital implant impression: An in vitro study

PURPOSE

To assess and compare the accuracies of intraoral scanners (IOS) and stereophotogrammetry (SPG) devices for complete-arch digital implant impressions.

METHODS

A 4-analog model was digitized using a desk scanner to obtain a reference file. Thirty test scans were conducted using the investigated IOS device, while an additional 30 scans were performed using the SPG device. Using the best-fit algorithm, the resulting 60 test files were aligned with the reference file. Linear (ΔX, ΔY, and ΔZ-axis) and angular deviations (ΔANGLE) were evaluated. Three-dimensional (3D) deviation was calculated based on the Euclidean distance (ΔEUC). The analysis was stratified according to the scanning device and implant position. Fisher's F and t-tests were used to compare the variances and expected values of the two scanning systems.

RESULTS

IOS expressed a higher 3D (ΔEUC) mean deviation than SPG (52.8 µm vs. 33.4 µm, P < 0.0001), with extreme measurements up to 181.9 µm. A significantly higher standard deviation (SD) was associated with IOS (37.1 µm vs. 17.7 µm, P < 0.0001). Considering angular deviations, the IOS showed slightly higher angular mean deviations (ΔANGLE) than the SPG (0.28° vs. 0.24°, P = 0.0022), with extreme measurements of up to 0.73°. The SPG SD values were significantly lower than the IOS SD values (0.14° vs. 0.04°, P < 0.0001).

CONCLUSIONS

The SPG showed significantly higher 3D and angular accuracies for complete arch implant impressions, with consistent repeatability. IOS scanning revealed significantly higher extreme deviations exceeding the acceptable threshold value. Despite study limitations, SPG appears more feasible than IOS for complete-arch digital implant impressions.

Functional Neuromyofascial Activity: Interprofessional Assessment to Inform Person-Centered Participative Care-An Osteopathic Perspective

Introduction: Health professionals and bodyworkers may be pivotal in promoting prevention programs, providing tailored advice and guidance to patients' adherence to self-care strategies, such as physical activity. Contemporary evidence encourages manual therapists to involve patients in decision-making and treatment procedures integrating passive and active approaches in treatment planning. This manuscript provides a definition and applications of neuromyofascial movement patterns, discusses the significance of functional assessment, and gives an example of clinical applications in the osteopathic field to highlight how this assessment can promote interdisciplinarity. Methods: The reporting framework used in the current manuscript followed guidelines for writing a commentary. Results: The manuscript highlights the crucial role that the neuromyofascial system plays in human movement and overall well-being and the importance of a functional neuromyofascial activity assessment in the context of person-centered participative care. Conclusions: Understanding individual neuromyofascial patterns could help healthcare practitioners, movement specialists, and bodyworkers in tailoring treatment plans, meeting patients' unique needs, and promoting a more effective personalized approach to care. The current perspective could spark debates within the professional community and provide a research roadmap for developing an evidence-informed interprofessional framework.

Accuracy of complete-arch digital implant impression with intraoral optical scanning and stereophotogrammetry: An in vivo prospective comparative study

OBJECTIVES

To assess accuracy of intraoral optical scanning (IOS) and stereophotogrammetry (SPG), complete-arch digital implant impressions in vivo.

MATERIALS AND METHODS

Consecutive patients needing implant-supported screw-retained zirconia complete-arch fixed-dental prostheses (ISZ-FDP) were recruited. For each patient, three impressions were taken: IOS, SPG (tests), and open-tray plaster (reference). Linear (ΔX, ΔY, and ΔZ), three-dimensional (ΔEUC), and angular deviations (ΔANGLE) were evaluated and stratified according to scanning technology for each implant. Potential effects of impression device (IOS and SPG), arch (maxilla and mandible), and implant number (4 and 6) were evaluated through multivariable analysis. Significance level was set at .05.

RESULTS

A total of 11 complete arches (5 maxillae, 6 mandibles) in 11 patients were rehabilitated with ISZ-FDPs supported by 4 (n = 8) and 6 implants (n = 3). A total of 50 implants and 100 implant positions were captured by two investigated devices and compared to respective reference (mean ΔEUC IOS 137.2, SPG 87.6 μm; mean ΔANGLE 0.79, 0.38°). Differences between measurements (SPG-IOS) were computed for each implant, with negative values indicating better SPG accuracy. Significant mean ΔEUC difference of -49.60 μm (p = .0143; SD 138.15) and mean ΔANGLE difference of -0.40° (p < .0001; SD 0.65) were observed in favor of SPG. Multivariable analysis showed significant effect on ΔEUC (p = .0162) and ΔANGLE (p = .0001) only for impression devices, with SPG performing better.

CONCLUSIONS

SPG experienced significantly higher linear and angular accuracy. No effect of type of arch or implant number was detected. Higher extreme deviations were experienced for IOS. SPG can be feasible for complete-arch digital impressions with caution, and rigid prototype try-in is recommended before screw-retained prosthesis manufacturing.

Long-term survival and success of zirconia screw-retained implant-supported prostheses for up to 12 years: A retrospective multicenter study

STATEMENT OF PROBLEM

Despite the broad clinical application of zirconia for fixed implant-supported prostheses, evidence of long-term performance is sparse.

PURPOSE

The purpose of this retrospective study was to evaluate the long-term clinical and radiographic outcomes of zirconia-based partial and complete screw-retained implant-supported zirconia fixed dental prostheses (ISZFDPs).

MATERIAL AND METHODS

Records of patients treated with dental implants and ISZFDPs between December 2004 and June 2017 were screened. Eligible study participants, according to inclusion criteria, were contacted and invited to undergo clinical and radiographic examinations. Outcomes were evaluated as implant and prosthetic survival rates, prosthetic success rate, complications, marginal bone level (MBL) change, and soft tissue condition. Along with the effects of zirconia prosthesis type and level, the effects of implant type and connection, type of loading, and follow-up on MBL were tested with a generalized linear effects model (GLEM) (α=.05).

RESULTS

A total of 118 patients were identified, of whom 20 (16.9%) were not available for clinical examination for various reasons. Ninety-eight participants (mean age 60.7 ±11.7 years) with 337 implants were included, of which 176 (52.2%) had been immediately loaded. A total of 111 ISZFDPs (96 zirconia connection and 15 titanium base) were investigated: 24 complete ISZFDPs with a zirconia connection (12.9 ±0.97 dental units, minimum 12, maximum 14), 72 partial with a zirconia connection (3.11 ±1.12, minimum 2, maximum 7), 15 partial with a titanium base (3.62 ±1.02, minimum 2, maximum 5). Forty ISZFDPs had been in function for ≥10 years (36%), 38 for 5 to 9 years (34.2%), and 33 for 2 to 4 years (22.8%). The mean follow-up time was 7.2 ±3.4 years. No zirconia fractures were identified. Two implants and 2 ISZFDPs failed, with chipping being the most common complication (13.5%). The implant survival rate was 99.4%, and the prosthetic survival rate was 98.2%. The cumulative prosthetic success rate was 91.9%. MBL change was -0.18 ±0.59 mm. Thirteen implants were treated for peri-implantitis (3.8%), and 9 for mucositis (2.7%), but presented healthy peri-implant soft tissues at the follow-up examination. A significant difference was found between the implant-level and abutment-level prostheses (P=.013), with less marginal bone loss observed in ISZFDPs delivered at the implant level.

CONCLUSIONS

Zirconia-based screw-retained implant-supported prosthesis can be considered a reliable long-term treatment option for partial and complete edentulism. No zirconia fractures were experienced. Stable bone levels and low peri-implantitis rates were reported regardless of the ISZFDP type and level, implant type and connection, and type of loading.

“What you feel under your hands”: exploring professionals’ perspective of somatic dysfunction in osteopathic clinical practice—a qualitative study

Background

Despite controversy regarding its validity and clinical usefulness, manual examination findings still have an important role for manipulative therapies. As an example, somatic dysfunction (SD) remains central to osteopathic practice.This study aims to explore the experienced osteopaths' attitudes concerning SD and its role in osteopathic practice. This qualitative research could contribute to building a consistent paradigm for manual intervention in all musculoskeletal manipulations.

Methods

A thematic analysis with grounded theory elements was used. Data were collected through semi-structured interviews carried out between February and April 2021. A purposive sample of twenty professional osteopaths with past experience in osteopathic care was chosen to reflect the phenomenon's variety. The data analysis was done inductively and in tandem with the recruiting to keep track of data saturation.

Results

Eleven osteopaths participated in the study. Three main themes emerged from the data analysis: (1) SD as a safe tissue-touch-based communication tool between operator and person complex adaptive health system; (2) The treatment of SD is shareable between osteopaths, other health professionals, and the patients involved in the therapeutic pathway improving body awareness and health; (3) The development of the SD concept in research and practice to better clarify osteopathic profession identity and definition.

Conclusions

A panel of expert osteopaths consider the concept of SD as a valuable tool integrated into the osteopathic evaluation and treatment process. The shared concept and clinical application of SD is informed by person-centered care concepts and from the fields of neuroscience, cognitive and complexity science. Our study reports a common need among osteopaths to develop an evidence-based framework of SD to allow the best development of the osteopathic profession.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12998-022-00444-2.

Influence of Implant Scanbody Wear on the Accuracy of Digital Impression for Complete-Arch: A Randomized In Vitro Trial

The aim of this study was to evaluate the influence of implant scanbody (ISB) wear on the accuracy of digital impression for complete-arch. A polymethylmethacrylate (PMMA) edentulous mandibular model with four internal hexagonal interlocking conical connections was scanned with an extraoral optical scanner to achieve a reference file. Four cylindrical polyetheretherketone (PEEK) ISBs were scanned 30 times with IOS, and the test files were aligned to the reference file with a best-fit algorithm. For each analog linear (ΔX, ΔY and ΔZ-axis) and angular deviations (ΔANGLE) were assessed. Euclidean distance (ΔEUC) was calculated from the linear deviation, reporting a mean of 82 µm (SD 61) ranging from 8 to 347 µm. ΔANGLE error mean was 0.33° (SD 0.20), ranging from 0.02 to 0.92°. From a multivariate analysis, when ΔEUC was considered as a response variable, a significant influence of ISB wear by scan number in interaction to position for implant 3.6 was identified (p < 0.0001); when ΔANGLE was considered as a response variable, a significant effect of position 3.6 was recorded ((p < 0.0001). The obtained results showed that the ISB wear negatively influenced the accuracy of IOS, suggesting that ISB base wear could be detrimental for the seating of ISBs on angulated implants.

Navigation guided socket-shield technique for implant and pontic sites in the esthetic zone: A proof-of-concept 1-year prospective study with immediate implant placement and loading

OBJECTIVE

To assess clinical, radiological performance of novel navigation guided socket-shield technique (NSS) with immediate implant placement and loading.

MATERIALS AND METHODS

Eighteen patients (12 females; age 52.54 ± 4.92; 33-72) treated between January 2018 and June 2019, were investigated, and followed for at least 1 year after definitive prosthesis placement (mean 20.1 months, 18-23). Primary outcomes: implant and prosthetic success rates, surgical, biologic, prosthetic complications.

SECONDARY OUTCOMES

marginal bone loss (MBL), implant stability quotient (ISQ), pink esthetic score (PES), plaque and bleeding indexes.

RESULTS

Sixty-nine navigation guided socket-shield procedures were performed (27 implant-sites and 42 pontic-sites) and 27 implants (NobelParallel, NobelBiocare AG) positioned and immediately loaded. Mean insertion torque and ISQ at implant positioning were 49 ± 5.34 Ncm (36-74), 73 ± 5.72 (68-81). No implant failure was experienced. Two root-shield exposures with mucositis, ulceration and bleeding were reported at two pontic-sites (2.9%) and successfully treated. No complications were experienced at implant-site leading to an overall NSS success-rate of 100%. No prosthetic complications occurred. Mean MBL was -0.72 ± 0.26 mm (-0.42 to -1.06 mm). PES final at the last follow-up 12.84 ± 0.92. The plaque and bleeding scores were 18.5 ± 6.12 and 3.15 ± 2.21.

CONCLUSIONS

Within study limitations, dynamic navigation was effective to streamline execution of socket-shield technique at implant and pontic sites, shortening treatment time and reducing complications. Navigation guided socket-shield technique was reliable to achieve digitally planned shield-to-implant distance, facilitate immediate implant placement and loading and establish the mucosal dimension needed for underlying bone-to-implant protection and esthetic integration.

CLINICAL SIGNIFICANCE

The investigated NSS technique overcomes the difficulties related to root preparation at implant and pontic-sites, facilitating immediate implant placement and loading. Dynamic guided surgery contributed to make socket-shield technique less technical-sensitive, shortening time for execution, reducing complication rate.

Clinical and radiological outcomes of novel digital workflow and dynamic navigation for single-implant immediate loading in aesthetic zone: 1-year prospective case series

Objectives

To evaluate clinical, radiological performance of novel digital workflow integrating dynamic navigation to streamline in one‐visit single‐implant immediate loading in aesthetic zone.

Material and methods

Consecutive patients requiring one single‐implant in aesthetic zone of both jaws were treated between May and September 2017. Primary outcomes were implant and prosthetic success rates, surgical and prosthetic complications, marginal bone loss (MBL), final pink aesthetic score (PES‐f), and implant stability quotient (ISQ‐f). Secondary outcomes were ISQ‐0 and PES‐0 at implant positioning and PES‐p at definitive prosthesis placement. Potential effect of jaw (maxilla vs mandible), biotype (thin vs thick), type of incision (flap vs flapless), and implant site (healed vs. post‐extractive) on the primary outcomes (MBL, PES‐f, and ISQ‐f) was evaluated through a multivariable analysis.

Results

Fifty‐two implants were placed (follow‐up 18.6, 15–20 months). One post‐extractive implant failed. No other surgical, biological complications occurred, accounting for 98.10% cumulative success rate (CSR). No definitive prostheses failed. Mean MBL was −0.63 ± 0.25 mm (−1.69 to −0.06). PES‐f was 12.34 ± 1.41 (9–14). ISQ‐f was 78.1 ± 3.2 (70–84). Age had significantly negative effect on MBL and PES‐f (p = .0058 and p = .0052). No other variables significantly affected primary outcomes.

Conclusions

Within study limitations, investigated digital workflow integrating dynamic navigation was reliable for single‐implant immediate loading in aesthetic zone in one visit. No statistically significant difference was found for MBL, PES‐f, and ISQ‐f, considering type of incision (flap vs. flapless), implant site (healed vs post‐extractive), jaw (maxilla vs. mandible), and biotype (thick vs. thin). Live‐tracked dynamic navigation may have contributed to improve operator clinical performance regardless of implant site characteristics. Further investigations are needed to confirm positive outcomes.

Guided endodontic microsurgery in apicoectomy: a review

The purpose of this review was twofold. The first aim was to show predictable protocols of guided endodontic microsurgery (EMS) and to describe its clinical outcomes. The second aim was to verify the accuracy of this technique compared to the traditional pathway. An electronic search of publications was established from two electronic databases, Cochrane and PubMed, by two independent researchers. The search strategy used a combination of controlled vocabulary and free-text words. Inclusion and exclusion criteria were defined by the authors before the start of the study. Inclusion criteria were: all studies published in English language; studies in vivo on humans; human cadaver studies; studies analyzing guided surgery in apicoectomy. The initial search yielded 67 citations, of which 10 were included. The studies included in this review analysis have shown two different technique both for digitization of dental arch and for surgical procedures too. Guided endodontic micro-surgery is a more predictable technique with less intra-operative and post-operative complications compared to the "freehand" technique and this procedure has shown a greater accuracy.

Different renal manifestations associated with very early onset pediatric inflammatory bowel disease: case report and review of literature

Background

Inflammatory bowel diseases are characterized by chronic inflammation of the gastrointestinal tract. In particular, Crohn disease and ulcerative colitis represent the two most common types of clinical manifestations. Extraintestinal manifestations of inflammatory bowel diseases represent a common complications, probably reflecting the systemic inflammation. Renal involvement is reported in 4–23% of cases. However, available data are limited to few case series and retrospective analysis, therefore the real impact of renal involvement is not well defined.

Case presentation

We report the case of a 10-years old male affected by very early onset unclassified-Inflammatory bowel diseases since he was 1-year old, presenting with a flare of inflammatory bowel diseases associated with acute kidney injury due to granulomatous interstitial nephritis. Of interest, at 7-year-old, he was treated for IgA nephropathy.

To our knowledge, no previous reports have described a relapse of renal manifestation in inflammatory bowel diseases, characterized by two different clinical and histological phenotypes.

Conclusions

The link between the onset of kidney injuries with flares of intestinal inflammation suggest that nephritis maybe considered an extra-intestinal manifestation correlated with active inflammatory bowel disease. However, if granulomatous interstitial nephritis represents a cell-mediated hypersensitivity reaction than a true extraintestinal manifestation of inflammatory bowel diseases is still not clarified. We suggest as these renal manifestations here described may be interpreted as extraintestinal disorder and also considered as systemic signal of under treatment of the intestinal disease.

Mechanical Pull-Out Test of a New Hybrid Fixture-Abutment Connection: An In Vitro Study

Implant abutment connection was described among the main causes of peri-implant bone resorption. The aim of this in vitro study was to test the coupling capacity, the surface modification of a new hybrid connection and the influence of repeated connection activations caused during the main clinical and laboratory phases. A total of 40 implant-abutment screw retained systems with 10°-conical and internal hexagon connection were tested. The connection was screwed, fixed to the universal test machine, removed the screw and a pull-out test was performed. Test was repeated five times in succession. Also Scanning Electron Microscopy (SEM) was used to detect microscopically surface modification. Analysis of variance and Tukey tests were used for the statistical analysis. Pull-out test reveals a mean value of 131.35 ± 16.52 Newton Centimeter (N·cm). For each single activation, results from first to fifth were: 113.9 ± 13.02, 126.1 ± 12.81, 138.11 ± 15.15, 138.8 ± 11.90 and 140 ± 12.99 N·cm. A statistically significant difference between the measurements and an increase in the removal force was shown. The collected data supports the use of this new type of connection, resulting in a very strong interface between implant and abutment. Also, repeated activation of connection can promote a better coupling of the implant-abutment interface.

Dynamic navigation guided surgery and prosthetics for immediate loading of complete-arch restoration

OBJECTIVE

To assess clinical and radiological performance of novel digital workflow integrating dynamic guided surgery, to streamline execution of implant placement, soft and bone tissue sculpturing, and immediate delivery of navigation guided complete-arch prosthesis.

MATERIALS AND METHODS

This proof of concept prospective single cohort study investigated 10 consecutive patients (three males, seven females; mean age 62.5 ± 8.9 years; range, 48-75) requiring at least one complete-arch fixed dental prostheses (FDP) in both jaws, treated between January and August 2019. Primary outcomes were implant and prosthetic success rates, surgical and prosthetic complications. Secondary outcomes were marginal bone loss (MBL), implant stability quotient (ISQ), periodontal parameters (plaque and bleeding indexes).

RESULTS

Sixty implants (32 NobelParallel TiUltra and 28 NobelActive TiUltra, Nobel Biocare) were placed and 14 complete-arch FDPs immediately loaded (mean follow-up 16.2 ± 1.7 months, 14-18). One implant failed and was immediately replaced. No other surgical or biological complications occurred, accounting for a cumulative success rate of 98.3%. No prosthetic complication occurred, leading to 100% prosthetic success rate. Mean ISQ at implant placement was 71 ± 2.8 (65-78). The mean MBL was -0.53 ± 0.28 mm (-0.22 to -1.12 mm). Plaque and bleeding scores were 14.4 ± 8.18 and 7.15 ± 4.4, respectively.

CONCLUSION

Within the limitations of this proof-of-concept dynamic navigation was effective to deliver in the planned coordinates both implants and prosthesis and guide bone and soft tissue sculpturing. Immediate loading of digitally prefabricated esthetically driven complete-arch FDP was facilitated, resulting in high implant and prosthetic success rates.

CLINICAL SIGNIFICANCE

The investigated digital workflow integrating dynamic navigation may overcome the difficulties related to immediate positioning and loading of digitally prefabricated complete-arch FDP. The navigation guided soft and bone tissues sculpturing, associated to xenogeneic collagen matrix grafting, represented a predictable technique to achieve the digitally planned interface, reestablishing the mucosal dimension required for the protection of underlying bone while maintaining tissue health.

Digital assisted soft tissue sculpturing (DASS) technique for immediate loading pink free complete arch implant prosthesis

PURPOSE

To introduce a digitally assisted technique to achieve the ideal soft and bone tissue interface for anatomic-driven pink free implant supported fixed prosthesis, and prefabricate an interim prosthesis to be used the day of the surgery as a prosthetic scaffold to condition the healing.

METHODS

The digital assisted soft tissue sculpturing (DASS) technique allows the previsualization of the ideal soft and bone tissue interface and fabricate a computer aided design computer aided manufacturing (CAD-CAM) anatomic-driven pink free complete arch interim prosthesis for the immediate loading. Bone and soft tissue interface as well as the interim prosthesis design are performed in a segmented multiple standard tessellation language (STL) file embedding the bone anatomy, the intraoral surface anatomy (dental and soft tissue), the digital wax-up and the implant positioning. The interim prosthesis is used as a prosthetic scaffold to guide the soft and bone tissue surgical sculpturing and regeneration.

CONCLUSIONS

The DASS technique is a predictable integrated digital workflow that simplifies the achievement of a scalloped tissue interface for pink free fixed implant prosthesis, reestablishing the mucosal dimension required for the protection of underlying bone while maintaining tissue health. The surgical sculpturing and maturation of the soft and bone tissue is driven and enhanced by the xenogeneic collagen matrix grafting and prosthetic scaffold effect of the digitally prefabricated interim prosthesis delivered the day of the surgery.

The effectiveness of subgingival irrigant ozone-based as adjuvant for non-surgical periodontal therapy in the treatment of chronic periodontitis: a review

The aim of this review was to establish the efficacy of Ozone therapy (OT) in Periodontal disease's (PD) tratment. An electronic search of publications was established from two electronic databases: PubMed and Web of Science. The search strategy used a combination of controlled vocabulary and freetext words. Inclusion and exclusion criteria were defined by the authors before the start of the study. The inclusion criteria were: all studies published in English language; studies in vivo on humans; studies analyzing the correlation between PD and OT. The search resulted in 102 titles. Only 9 articles were included in the quantitative analysis. By the analyzed studies a strictly connection is still not evincible. More clinical trials are recommended to investigate the role of ozone, in its various types of topical administration, as a valid subgingival irrigant to achieve the goal of periodontal tissue health.

Rehabilitation of a severe mandibular atrophy with four millimeter extra-short implant and guided bone regeneration (GBR): case report with 7-years follow-up

The aim of this study was to report the use of extra-short and short implants in combination with Guided Bone Regeneration (GBR) to rehabilitate a case of severe mandibular reabsorption. A 55-yearold female patient asked for a fixed implant supported rehabilitation in 4.5 - 4.6 zone which showed severe atrophy. It was decided to use an extra-short 4 mm length and 4.1 mm Ø, Roxolid and SLActive implant (Straumann Standard Plus Regular Neck, Institut Straumann AG) in 4.5 position and a short 6 mm length and 4.8 mm Ø, Roxolid and SLActive implant (Straumann Standard Plus Wide Neck, Institut Straumann AG) in 4.6 position. The implants supported cemented fixed prosthesis. Examinations were performed at the day of the surgery and up to 7-years in function to evaluate implant stability and periapical radiography. One extra-short implant and one short implant were placed. After 7 years in function no biological or prosthetic complication were recorded. Within the limitation of this case report, the use of short and extra-short implants to support fixed prosthesis seem to be a feasible treatment alternative in severe mandibular atrophy.

Comparison of the accuracy of intraoral scanning and conventional impression techniques on implants: a review

The aim of this review was to collect available evidence and evaluate accuracy outcomes of dental implant impression techniques, and to compare the accuracy of conventional implant impression versus digital implant impression. Inclusion and exclusion criteria were defined by the authors before the start of the study. The inclusion criteria were: all studies published in English language; studies no older than five years; analyzing the accuracy of digital vs conventional technique impression on implants. The exclusion criteria were: publications that reported the same data as later publications by the same authors and systematic reviews; commentaries and letters to the editor; case report and case series. The search resulted in 106 titles. Following the first stage of screening, after the records identification through database manual searching, 112 potentially relevant studies were identified. After the second stage screening, 33 full text publications were obtained and analyzed and 17 were excluded. Afterwards, 18 articles resulted eligible after full text reading and a cross search of the articles' references was accomplished; 3 articles were consequently added. At the end only 7 articles were included in the quantitative analysis. Within the limitations of this systematic review, digital impression on dental implants offers a comparable accuracy compared with conventional impressions technique. More clinical trials are recommended to investigate the accuracy of these scanners and their validity in clinical use.

Influence of implant scanbody material and operator on scanning fluency and polygonal mesh numbers of digital impression: an in vitro study

The purpose of this study is to evaluate the influence of implant scanbody (ISB) material and operator on scanning fluency and polygonal mesh numbers of a confocal microscopy intraoral scanning (IOS). An edentulous maxillary master model with 6 implant analogues was assembled. Thereafter 3 ISBs featured with same geometry but different materials (polyetheretherketone (PK), titanium (T) and PK with a titanium base (PKT)) were produce and scanned according to a randomized sequence by three different operators. The confocal microscopy IOS resulted in 45 STL test files that were processed to a dedicate software to obtain the request data. The overall analysis of fluency (imm/sec) showed the following results: mean 11.997 imm/sec, SD 2.355. The multivariate analysis showed statistical significance of material (p<.0001) and operator (p<.0001) influence. The univariate analysis referred to polygonal mesh numbers expressed the following results: mean 30327.8, SD 2432.5. The multivariate analysis stressed how there is a related effect to materials (p<.0001) and operator (p=0.0205). PKT represented the material with the best results for both. Analyzing the overall distribution histogram for scanning fluency, the IOS device seems to work with higher frequency at level of 13 imm/sec. The distribution of the measurements in the reference histograms showed an effect related to both variables referring to scanning fluency as well as to polygonal mesh numbers. Operator can be considered as a random effect; regarding the materials, the difference between PKT and PK can be related to the different base material. The dissimilar optical properties of T justify the different behavior.

Influence of implant scanbody material, position and operator on the accuracy of digital impression for complete-arch: A randomized in vitro trial

PURPOSE

To evaluate the influence of implant scanbody (ISB) material, position and operator on the accuracy of a confocal microscopy intraoral scanning (IOS) for complete-arch implant impression.

METHODS

An edentulous maxillary model with 6 internal hexagonal connection analogues was scanned with an extraoral optical scanner to achieve a reference file. Three ISBs made of different materials (polyetheretherketone (Pk), titanium (T) and Pk with a titanium base (Pkt)) were scanned with IOS by 3 operators. The resulting 45 test files were aligned to the reference file with a best fit algorithm. Linear (ΔX, ΔY and ΔZ-axis) and angular deviations (ΔANGLE) were assessed. Absolute values of the linear discrepancies were summed up to obtain a global measure of linear absolute error (ΔASS). Influence of ISB material, position and operator was statistically assessed using the mixed general linear model.

RESULTS

At multivariate analysis, whenΔASS was considered as response variable, it was identified a significant influence of material (p<0.0001) and position (p=0.0009) while no significant operator effect was detected. When ΔANGLE was considered as response variable, material and position significantly influenced the expected ΔANGLE (p=0.0232 and p<0.0001) and no operator effect was identified.

CONCLUSIONS

The investigated IOS for complete-arch digital impression was influenced by the ISB material with peek reporting the best results on both linear and angular measurements followed by titanium, peek-titanium resulting as the less accurate. Implant angulation affected significantly the linear deviations while implant position the angular deviations. Operator did not show any significant effect on the IOS accuracy.

Fit evaluation of cad/cam fabricated all-ceramic restorations based on direct and indirect digitalization in vivo: a systematic review

The aim of this study was to compare the fit of all-ceramic restorations on natural teeth fabricated through a direct digital workflow or an indirect digital workflow. An electronic search of publications was established from three electronic databases: Cochrane, PubMed and Web of Science. The search strategy used a combination of controlled vocabulary and free-text words. The detailed search design and strategies, including keywords, are presented below. The authors used two filters to follow data for the research: papers written in English and published in the last 5 years. The search resulted in 3042 titles. Following the first stage of screening, after the records identification through database manual searching, 3047 potentially relevant studies were identified. After the second stage screening, 38 full text publications were obtained and analyzed and 17 were excluded. Afterwards, 22 articles resulted eligible after full text reading and a cross search of the articles references was accomplished and 5 articles were consequently added. At last, 6 articles were included in the quantitative analysis. This study was designed to compare the fit of restorations obtained by means of a direct or indirect digital workflow. The values reported on the maximum acceptable gap in scientific literature range from 50 to 200 μm, so there does not seem to be an objective limit based on scientific evidence. According to the most accepted marginal discrepancy in the literature, most of the values of the studies examined are in the 200 μm acceptability range. Within the limitations of this systematic review, computer-aided design and computer-aided manufacturing (CAD/CAM) fabricated restorations obtained by means of an intraoral scanner (IOS) showed better marginal and internal fit than restorations obtained through conventional impression and subsequent laboratory scanning. According to the results of this systematic review, the direct digital workflow resulted as a valid alternative to the indirect digital workflow to produce CAD/CAM all-ceramic restorations.

Radiosurgery in dentistry: a review

The aim of the present study was to analyse the clinical potential of radiosurgery applied to modern dentistry through a revision of the indexed literature. Radiosurgery represents a recent form of electrosurgery working at a frequency of 3.0-4.0 MHz. The depth of penetration of the waves is inversely proportional to the frequency. Radiowaves working at high frequency express a lower penetration with a consequent lower tissue alteration. The authors analyzed the literature in order to give to the scientific community an overview of the possible applications of radiosurgery in the clinical dental practice and their effectiveness. Radiosurgery can be used in prosthodontics, in periodontal and implant surgery, in the treatment of trigeminal neuralgia, in the treatment of obstructive sleep apnea syndromes (OSAS) and in endodontics. Our analysis shows that although there are few articles in indixed literature on the applications of radiosurgery in dentistry, thanks to the benefits that derive from it, radiosurgery will spread more in the daily clinical practice of the dentists.

Temporary Shell Proof-of-Concept Technique: Digital-Assisted Workflow to Enable Customized Immediate Function in Two Visits in Partially Edentulous Patients

The growing interest in minimally invasive implant placement and delivery of a prefabricated provisional prosthesis immediately, thus minimizing "time to teeth," has led to the development of numerous 3-dimensional (3D) planning software programs. Given the enhancements associated with fully digital workflows, such as better 3D soft-tissue visualization and virtual tooth rendering, computer-guided implant surgery and immediate function has become an effective and reliable procedure. This article describes how modern implant planning software programs provide a comprehensive digital platform that enables efficient interplay between the surgical and restorative aspects of implant treatment. These new technologies that streamline the overall digital workflow allow transformation of the digital wax-up into a personalized, CAD/CAM-milled provisional restoration. Thus, collaborative digital workflows provide a novel approach for time-efficient delivery of a customized, screw-retained provisional restoration on the day of implant surgery, resulting in improved predictability for immediate function in the partially edentate patient.

Radiosurgery-assisted gingival displacement: a proof of concept technique to enhance the efficiency of intraoral digital impression

Nowadays, an increasing number of dentists are using intraoral scanners (IOS) in their daily practice as an alternative to conventional impression taking. One of the main concerns is related to the capability of scanning the subgingival anatomy of the die, usually very challenging due to the limited operative field and the presence of oral fluids. The radiosurgery assisted gingival displacement technique (RAGD) may enhance the intraoral optical scanning of the finish line and neighbor tooth anatomy. The contour of the interim prosthesis is used to drive the tip of radiosurgery electrode along the tooth surface and open selectively the gingival crevice with a prosthetically-driven and minimally invasive approach. The clinical implication of this technique is related to increasing the efficiency and accuracy of the digital impression technique in the critical zone of the prosthetic shoulder.

Marfan Syndrome: oral implication and management

Marfan's Syndrome is a multisistemic pathology of connective tissues, a dominant autosomal transmission, first discovered by a French pediatrician, Antoine Bernard-Jean Marfan, who first found in some of his patients a disproportionate alteration of inferior infertility. This alteration was caused by the mutation of the FBN1 gene, located on the long arm of the chromosome 15, which encodes for an extracellular matrix protein, fibrin-1. Later it was discovered that the disease could occasionally be due also to the mutation of the TGFBR2 gene, which encodes for a TGF-beta receptor 1. The estimated incidence of the disease is 2-3 subjects affected every 10,000, in the absence of predilection ratial, ethnic, geographic and gender. It is believed that some 15,000 people in Italy suffer from Marfan Syndrome. The disease is characterized by a wide range of clinical manifestations that affect different organs. The study evaluates through a literature review the manifestations in the oral cavity of the marfan syndrome and the correct management of the patient during dental maneuvers.

In vitro evaluation of the post-space depth reading with an intraoral scanner (IOS) compared to a traditional silicon impression

Objectives

The aim of the study was to assess the depth and quality of the post-space reading, using an IOS without scan-post, compared to a traditional silicon technique.

Methods

Six extracted bicuspids were decoronated and endodontically treated. After having prepared the space for the posts, a structure in pink acrylic resin was created with two resin elements. At the center of the structure one sample was put at a time. Digital and traditional impressions were taken for each sample.Digital impressions were developed through the Computer-aided design (CAD) software in order to integrate the scanner results into a three-dimensional grid to make the measurements. A K-file was used to measure the length of the post-space of each sample obtained through the traditional silicon impression and subsequently the measurement results were reported on a millimeter gauge. Furthermore, an assessment of the width of the entrances of the post-spaces was carried out.

Results

The mean reading depth discrepancy expressed in percentages (19.58%) indicates that the digital impression with current technologies fails to impress clearly the post-space. Standard deviation of the data expressed in percentage is 13.89, suggesting that the values were not similar to each other. In two cases the digital technique has achieved less than 10% difference compared to the traditional technique, but there have been also cases in which the variation in depth has reached almost 40%.The samples that showed the minor discrepancy between the two techniques expressed the widest post-space entrance.

Conclusions

In this in vitro study, the application of the IOS for the post-space reading in order to deliver an anatomic post has been proven to be still not reliable, as there are still depth reading limitations for the narrow root channels. In fact, in this type of channels it is difficult to reach with the light beam of the IOS the deepest areas of the post-space, with a consequent incomplete post-space reading.

Smart fusion vs. double scan: a comparison between two data-matching protocols for a computer guided implant planning

AIM

To make a comparison between two different approaches of data matching during the preparation of a computer guided implant planning.

MATERIAL AND METHODS

Electronic and manual literature searches were performed to collect information about the double-scan protocol and the smart fusion protocol. The two systems were then tested to identify or confirm their advantages and disadvantages.

RESULTS

The double scan protocol is a reliable and well-known process to obtain a fusion between the anatomical data (CBCT) and the prosthetic data (radiographic template). It is possible to use this protocol both in dentate and edentulous patients. The newly developed smart fusion technique offers the possibility to superimpose the anatomical data (CBCT) onto the prosthetic data (cast + wax-up scan) without the production of a radiographic template. This system is still being tested by the clinicians even though dental manufacturers already consider it as the best solution for the dentate patients selected for a static computer guided implant surgery.

CONCLUSIONS

Smart fusion protocol offers a reasonable time and cost reduction even though its application is limited to dentate patients. A noticeable drawback of the workflow is the matching step: often a manual intervention is necessary to obtain a correct alignment of the CBCT data with the lab scan of the cast. This issue is partially due to the use of non-volume stable materials during the preparation of the cast. Future improvements could be made by combining CBCT data with direct optical scans of patient dental arches in order to create the so-called 'virtual patient'.

Dental photography today. Part 1: basic concepts

This paper is the first article in a new series on digital dental photography. Part 1 defines the aims and objectives of dental photography for examination, diagnosis and treatment planning, legal and forensic documentation, publishing, education, marketing and communication with patients, dental team members, colleagues and dental laboratory.

Full digital workflow for implant-prosthetic rehabilitations: a case report

OBJECTIVES

The aim of the present study was to describe a proof of concept digital workflow for the implant-prosthetic treatment in partially edentate patients and evaluate its clinical performance.

METHODS

A 55-year-old woman with a Kennedy class III bilateral edentulism in the mandible has been selected for a computer guided implantology according with the Smart Fusion® protocol (NobelBiocare, Kloten, Switzerland). After the template-guided implant placement, an immediate loading of the implants has been performed. QuickTemp conical temporary abutments were selected to deliver immediately prefabricated cement-retained provisionals. Two months after an impression was taken with an intraoral digital scanner (3Shape Trios3, Copenhagen, Denmark). The provisional restoration optical scanning was used to transfer the functionalized prosthetic contour to be duplicated into the definitive porcelain fused to zirconia restoration cemented on customized titanium abutments.

RESULTS

A satisfying esthetic and functional result has been achieved. No biological and mechanical complications were recorded.

CONCLUSIONS

The investigated fully digital implant-prosthetic protocol provided a smooth, complication free and time effective treatment alternative to the conventional workflow. Besides the fully digital workflow allowed the surgical and prosthetic decision making and the communication within the dental team and with the patient. Further improvements heading to a direct match between the intraoral scan and the CBCT are strongly advised in order to create the so-called virtual patient.

A novel workflow for computer guided implant surgery matching digital dental casts and CBCT scan

Nowadays computer-guided "flap-less" surgery for implant placement using stereolithographic tem-plates is gaining popularity among clinicians and patients. The advantages of this surgical protocol are its minimally invasive nature, accuracy of implant placement, predictability, less post-surgical discomfort and reduced time required for definitive rehabilitation. Aim of this work is to describe a new protocol (Smart Fusion by Nobel Biocare), thanks to which is now possible to do a mini-invasive static guided implant surgery, in partially edentulous patients with at least 6 remaining teeth, without the use of a radiographic guide. This is possible thanks to a procedure named surface mapping based on the matching between numerous points on the surface of patient's dental casts and the corresponding anatomical surface points in the CBCT data. The full protocol is examined focusing the attention on the clinical and laboratory procedures.

CONCLUSIONS

Also with some critical points and needing an adequate learning curve, this protocol allows to select the ideal implant position in depth, inclination and mesio-distal distance between natural teeth and or other implants enabling a very safe and predictable rehabilitation compared with conventional surgery. It represents a good tool for the best compromise between anatomy, function and aesthetic, able to guarantee better results in all clinical situations.

Oral complications of head and neck radiotherapy: prevalence and management

AIM

The aim of the study was to evaluate the short-term and long-term toxicity caused by radiation treatment in the head and neck with the technique of intensity-modulated radiotherapy (IMRT).

METHODS

We selected 20 patients, 18 men and 2 women aged between 21 and 71 years, undergoing radiation therapy (IMRT) in head and neck. Patients were visited during radiotherapy and followed for six months after the end of the therapy. We assessed the presence of: mucositis, xerostomia, dysgeusia, dysphagia, pain, trismus and, in the case of late-onset complications, radiation cavities.

RESULTS

Acute toxicity: in 20 patients, 18 reported mucositis, 19 xerostomia, 17, dysgeusia, 15 dysphagia, 18 had pain and 3 patients had trismus. Tardive toxicity: in 14 patients, 5 reported mucositis, 11 xerostomia, 6 dysgeusia, 2 dysphagia, 3 had pain, 4 trismus and in 4 patients were found radiation cavities.

CONCLUSION

Acute complications with higher prevalence were xerostomia (19 of 20 patients), dysgeusia of 2nd grade (11 patients of 20), mucositis of 1st grade and pain of 1st grade (10 patients of 20). Among the late complications it was noted a maintenance of the high prevalence of xerostomia (11 patients of 14) and an increase in prevalence of trismus (4 patients of 14) against a reduction of all other complications. The presence of radiation cavities in 4 patients of 14 was also recorded.

Combined orthodontic-surgical approach in the treatment of impacted maxillary canines: three clinical cases

Impaction of maxillary canine is a relatively frequent orthodontic anomaly which could represent fuctional and aesthetic problems for patients. Nowadays, the conventional technique to impacted canines consists of a combined orthodontic and surgical approach, aimed to guide cuspids at the center of the alveolar ridge in a stable position and surrounded by healthy hard and soft tissues. This article presents three cases studies with different combined surgical-orthodontic approaches for the treatment of infraosseous impacted canines. An impacted maxillary canine could be guided, after adequate space is created orthodontically, to the center of the ridge through an orthodontic traction directly applied to the crown of impacted cuspid. Several surgical techniques have been proposed to expose the crown of impacted tooth. Location (buccal or palatal side) of impactation and depth influence surgical approach in order to obtain best aesthetic and functional results.

Language use in intergroup contexts: the linguistic intergroup bias

Three experiments examine how the type of language used to describe in-group and out-group behaviors contributes to the transmission and persistence of social stereotypes. Two experiments tested the hypothesis that people encode and communicate desirable in-group and undesirable out-group behaviors more abstractly than undesirable in-group and desirable out-group behaviors. Experiment 1 provided strong support for this hypothesis using a fixed-response scale format controlling for the level of abstractness developed from Semin and Fiedler's (1988a) linguistic category model. Experiment 2 yielded the same results with a free-response format. Experiment 3 demonstrated the important role that abstract versus concrete communication plays in the perpetuation of stereotypes. The implications of these findings and the use of the linguistic category model are discussed for the examination of the self-perpetuating cycle of stereotypes in communication processes.

Language use in intergroup contexts: The linguistic intergroup bias

Three experiments examine how the type of language used to describe in-group and out-group behaviors contributes to the transmission and persistence of social stereotypes. Two experiments tested the hypothesis that people encode and communicate desirable in-group and undesirable out-group behaviors more abstractly than undesirable in-group and desirable out-group behaviors. Experiment 1 provided strong support for this hypothesis using a fixed-response scale format controlling for the level of abstractness developed from Semin and Fiedler's (1988a) linguistic category model. Experiment 2 yielded the same results with a free-response format. Experiment 3 demonstrated the important role that abstract versus concrete communication plays in the perpetuation of stereotypes. The implications of these findings and the use of the linguistic category model are discussed for the examination of the self-perpetuating cycle of stereotypes in communication processes.