Perceived surgical difficulty of mandibular third molar extraction. A comparative cross-sectional study of dentists with postgraduate qualificationin oral surgery and maxillofacial surgeons in a Spanish subpopulation

Background: Mandibular third molar (MTM) extraction is one of the most frequently performed surgeries in the oral cavity. Establishing the level of surgical difficulty pre-operatively is an essential step to ensure correct treatment planning. In Spain, MTM extraction - especially in cases presenting greater difficulty - is normally performed by doctors specializing in oral and maxillofacial surgery, or by dentists with postgraduate qualifications in oral surgery. The present work set out to analyze the extent to which perceptions of surgical difficulty of the said intervention vary in relation to professional training. Material and Methods: This cross-sectional, descriptive, observational study took the form of a survey. Using a visual analog scale (VAS), participants evaluated both the perceived difficulty of 30 cases of MTM extraction described by means of digital panoramic radiographs and the perceived difficulty deriving from a series of factors conditioning MTM extraction. The results underwent statistical analysis with SPSS Statistics 28.0 software. Nonparametric tests (Mann Whitney test for independent samples and the Kruskal-Wallis test) were applied. Results: A total of 213 surveys were available for analysis. Both groups awarded the greatest importance to clinical experience, followed by anatomical and radiographic factors, root morphology obtaining the highest score among anatomical factors (9.01±1.42), while proximity of the MTM to the inferior alveolar nerve was regarded as the least important anatomical factor (8.11 ±2.54). Significant differences were only found for patient age, whereby maxillofacial surgeons awarded this factor more importance than dentists. Conclusions: The different training received by dentists specialized in oral surgery and maxillofacial surgeons did not influence either perceptions of surgical difficulty of MTM extraction, or opinions as to the factors influencing surgical difficulty. (AU)

How do the dimensions of peri-implant mucosa affect marginal bone loss in equicrestal and subcrestal position of implants? A 1-year clinical trial.

INTRODUCTION: There is evidence that the apico-coronal implant position and the mucosal phenotype can affect the extent of peri-implant bone loss. This clinical trial analyzes the bone remodeling and marginal bone loss that occur around conical-connection implants placed equicrestally and subcrestally, assessing the effect of the peri-implant soft-tissue phenotype. METHODS: Fifty-one patients received 56 implants of distinct diameters (3.5 mm Ø n = 6; 4.3 mm Ø n = 41; 5 mm Ø n = 9) in the posterior part of the maxilla or mandible. The implants were placed equicrestally, 1 mm subcrestally and >1 mm subcrestally, depending on the initial supracrestal tissue height (STH). After 3 months of non-submerged healing, single metal-ceramic screw-retained implant-supported crowns were placed. Longitudinal measurements of STH, mucosal thickness and keratinized mucosa width (KMW) were made at the time of implant placement (T0), crown placement (T1), and after 3 (T2) and 6 months (T3) of prosthetic loading. At each of these points, a radiographic evaluation of bone remodeling and marginal bone loss was also performed. RESULTS: STH was significantly greater for implants placed >1 mm subcrestally than for those placed 1 mm subcrestally. After 12 months of follow-up, a very significant (p < 0.001) loss of KMW was observed, in addition to a marginal bone loss of 0.08 ± 0.1, 0.15 ± 0.2, and 0.14 ± 0.2 mm in the groups placed equicrestally, 1 mm subcrestally and >1 mm subcrestally, respectively. After the multiple linear regression, marginal bone loss was found to depend primarily on KMW (ß = -0.43), while also being affected by STH (ß = 0.32) and implant diameter (ß = -0.28). CONCLUSIONS: Marginal bone loss may be influenced by the position with respect to the bone crest, as well as the KMW, STH, and implant diameter. However, more well-controlled studies are needed to verify these above-mentioned findings with different implant designs and connections.

Three-dimensional representation of the Vita Toothguide 3D-Master: An in vivo clinical study.

STATEMENT OF PROBLEM: The Vita Toothguide 3D-Master (Vita Zahnfabrik) is considered the dental shade guide in which the three dimensions of color - lightness, hue, and chroma - are most well-ordered in the CIELAB color space. No research has yet explored how well the Vita Toothguide 3D-Master is ordered in the 3D color space by recording color coordinates in vivo. PURPOSE: To evaluate the spatial color distribution of the Vita Toothguide 3D-Master's lightness, chroma, and hue groups and its 26 physical shade tabs. MATERIALS AND METHODS: The dental color (L*, C*, h°, a*, and b* color coordinates) of a healthy maxillary central incisor was recorded for 1361 participants (aged between 18 and 89 years) using a Vita Easyshade Compact spectrophotometer (Vita Zahnfabrik). The R 2.7.2. statistics program was used to create the visual representations. RESULTS: The five lightness levels are those that are best distributed in the color space, in relation to the L* coordinates, followed by the chroma group and, finally, the hue group. The 5M1, 5M2, and 5M3 physical shade tabs are situated at a greater distance apart from the other tabs in the color space. CONCLUSIONS: The Vita Toothguide 3D-Master's 26 physical shade tabs are satisfactorily distributed in three-dimensional space, although strict mathematical criteria are not followed. The natural dental shades that fall lower on the lightness scale are the most poorly represented by the physical shade tabs. CLINICAL IMPLICATIONS: Darker teeth are poorly represented by the Vita Toothguide 3D-Master's physical shade tabs. The spatial distribution of dental shade guides needs to be improved to ensure they provide homogeneous coverage of the entire chromatic spectrum corresponding to natural teeth. This would help reduce the errors inherent to the subjective visual color selection process.

Treatment of Esthetic Complications with Peri-implant Soft Tissue: A Description of the "Apical Approach" Surgical Technique and Presentation of Two Clinical Cases

Peri-implant soft tissue deformities are an increasingly common phenomenon in the esthetic zone. While the most widely studied esthetic complications are peri-implant soft tissue dehiscences, there are other esthetic concerns in routine clinical practice that require investigation and treatment. Thus, this report on two clinical cases describes a surgical approach using the apical access technique to treat peri-implant soft tissue discoloration and fenestration. In both clinical scenarios, the defect was accessed via a single horizontal apical incision without removing the cement-retained crowns. A bilaminar technique using apical access with a simultaneous connective tissue graft seems to offer promising results for the treatment of peri-implant soft tissue deformities. At the 12-month reevaluation, an increase in peri-implant soft tissue thickness was observed, resolving the pathologies presented.

Factors Influencing the Accuracy of Guided Surgery: An In Vitro Trial.

Purpose: To examine how the accuracy (linear and angular deviation) of implants placed using computer-guided surgery varies in relation to the type of surgical technique (fully guided, half-guided, vs freehand implant placement), bone density (type D1 to D4 bone), and type of support surface (tooth- vs mucosa-supported). Materials and Methods: A total of 32 mandible models were produced (16 partially edentulous and 16 edentulous) using acrylic resin, each calibrated to a different bone density (D1 to D4). Four implants planned using Mguide software were placed in each acrylic resin mandible. A total of 128 implants were placed, distributed according to bone density (D1 to D4, n = 32), the degree of intervention in the surgery (fully guided [FG] = 80, half-guided [HG] = 32, and freehand surgery [F] = 16), and the type of support surface (tooth-supported: n = 64 and mucosa-supported: n = 64). To determine the linear, vertical, and angular deviations between the planned three-dimensional position and the actual position of the implants, the linear and angular difference between them was calculated, with the analysis performed through preoperative and postoperative CBCT scans. The effect was analyzed using parametric tests and linear regression models. Results: All parameters of linear and angular discrepancy in the various regions analyzed (neck, body, and apex) were primarily influenced by the technique and, to a lesser extent, by the bone type, although both variables were predictive and highly significant. These discrepancies tend to increase in completely edentulous models. The regression models show that linear deviations increase by between 630.2 µm at neck level in the buccolingual direction and 836.7 µm at apex level in the mesiodistal direction when comparing the FG and HG techniques. This increase is accumulative when comparing the HG and F techniques. Regarding the effect of bone density, the regression models found that linear discrepancies increase by between 132.6 µm in the axial direction and 199.0 µm at the apex of the implant in the buccolingual direction with each reduction in bone density (D1 to D4). Conclusion: According to this in vitro study, the highest implant placement predictability is found among dentate models with high bone density and a fully guided surgical technique.

Successful kinetic impact into an asteroid for planetary defence.

Although no known asteroid poses a threat to Earth for at least the next century, the catalogue of near-Earth asteroids is incomplete for objects whose impacts would produce regional devastation1,2. Several approaches have been proposed to potentially prevent an asteroid impact with Earth by deflecting or disrupting an asteroid1-3. A test of kinetic impact technology was identified as the highest-priority space mission related to asteroid mitigation1. NASA's Double Asteroid Redirection Test (DART) mission is a full-scale test of kinetic impact technology. The mission's target asteroid was Dimorphos, the secondary member of the S-type binary near-Earth asteroid (65803) Didymos. This binary asteroid system was chosen to enable ground-based telescopes to quantify the asteroid deflection caused by the impact of the DART spacecraft4. Although past missions have utilized impactors to investigate the properties of small bodies5,6, those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. Here we report the DART spacecraft's autonomous kinetic impact into Dimorphos and reconstruct the impact event, including the timeline leading to impact, the location and nature of the DART impact site, and the size and shape of Dimorphos. The successful impact of the DART spacecraft with Dimorphos and the resulting change in the orbit of Dimorphos7 demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary.

Reconstrucción maxilar con un implante subperióstico en un caso de atrofia severa. De la planificación a la rehabilitación siguiendo un protocolo totalmente digital. A propósito o clínico y revisión bibliográfica / Maxillary reconstruction with a subperiosteal implant in a case of severe atrophy. From planning to rehabilitation following a fully digital protocol. A clinical case report and literature review

Introducción: Los implantes subperiósticos personalizados de titanio, diseñadosa partir de un software de planificación yfabricación, constituyen una alternativaen la rehabilitación de atrofias severasen los maxilares, evitando cirugías de reconstrucción óseas y el de partes blandasmás complejas y disminuyendo los tiempos de cicatrización. El objetivo de este trabajo es presentar la rehabilitación enun caso clínico con una atrofia severa enmaxilar superior, utilizando una estructuracon implantes subperiósticos, medianteun protocolo digital.Descripción del caso: Se diseñó unaestructura subperióstica de titanio sinterizada con seis conexiones transepitelialesque fueron rehabilitadas con una prótesisfija inmediata implantosoportada fabricada en PMMA. Dos meses después, serealizó una estructura sinterizada en cromo-cobalto con bases mecanizadas recubierta con dientes de resina acrílica comorestauración final. En el seguimiento a unaño, el caso permanece estable.Conclusiones: Hoy en día, la rehabilitación con implantes subperiósticos constituye una herramienta alternativa en casosde cirugías complejas con grandes atrofias con la posibilidad, además, de realizar una carga inmediata. (AU)

Introduction: Customized subperiosteal titanium implants, designed from planning and fabrication software, constitute analternative in the rehabilitation of severe maxillary atrophy, avoiding more complex bone and soft reconstruction surgeries and reducing healing times. The aim of this article is to present the rehabilitation in a clinical case with severe atrophy in the upper jaw, using a structure with subperiosteal implants, by means of a digital protocol.Clinical Case: A subperiosteal sintered titanium structure was fabricated with six transepithelial connections that were rehabilitated with an immediate implant-supported fixed prosthesis made of PMMA. Two months later, a sintered Chromium-Cobalt framework with machined bases covered with acrylic resin teeth was fabricated as the final restoration. At one year follow-up, the case remains stable. Conclusions: Nowadays, rehabilitatin with subperiosteal implants is an alternative tool in cases of complex surgeries with large atrophies with the possibility of immediate loading. (AU)

Injerto de tejido conectivo en combinación con la técnica de colgajo lateralmente cerrado para el tratamiento de recesiones gingivales anteroinferiores: resultado clínico y revisión sistemática comparativa / Connective tissue grafting in combination with the laterally closed flap technique for the treatment of anteroinferior gingival recessions: Clinical outcome and comparative systematic review

Objetivo: evaluar la eficacia clínica de latécnica del túnel lateralmente cerrado coninjerto de tejido conectivo en recesiones gingivales unitarias en el área antero inferior, mediante una serie de seis casos. Otro de los objetivos fue realizar una revisión de la literatura para comparar la eficacia de la técnica de técnica del túnel lateralmente cerrado frente a la técnica de colgajo de avance coronal con injerto de tejido conectivo. Material y métodos: seis pacientes con recesiones gingivales antero inferiores fueron tratados mediante la técnica del túnel lateralmente cerrado. Se recogieron distintas variables clínicas periodontales, especialmente la profundidad de la recesión para calcular el porcentaje de cobertura radicular de dicha técnica. Por otra parte, se realizó una revisión bibliográfica basada en la siguiente pregunta PICO:P (pacientes con recesiones gingivales unitarias en dientes anteriores mandibulares), I (técnica del túnel lateralmente cerrado con injerto de tejido conectivo),C (técnica de colgajo avance coronal),O (analizando profundidad de sondaje, profundad de recesión, nivel de inserción clínica, ancho de tejido queratinizado, grosor gingival, cobertura radicular mediay cobertura radicular completa). Resultados: en la serie de casos se obtuvo una cobertura radicular media del 96. 67% ± 8.17 %, siendo este resultado estadísticamente significativo. Al igual que en la reducción de la profundidad de recesión (p=0,001), del nivel de inserción clínica (p=0,003) y en la ganancia de anchura de tejido queratinizado (p=0,001) y grosor gingival (p<0,001). No siendo significativo la reducción de la profundidad de sondaje. En cuanto a la revisión sistemática, se comprobó que la profundidad de sondaje fue mayor en la técnica de colgajo de avance coronal,mientras que se obtuvieron mejores ganancias de anchura de tejido queratinizado con la técnica de túnel lateralmente cerrado...(AU)

Objective: To evaluate the clinical efficacy of the laterally closed tunnel technique with connective tissue grafting in single gingival recessions in the antero inferior area, using a series of six cases. Another objective was to carry out a review to compare the efficacy of the laterally closed tunnel technique versus the coronal advancement flap technique with connective tissue graft. Material and methods: Six patients with antero inferior gingival recessions were treated using the laterally closed tunnel technique. Different periodontal clinical variables were collected, especially the depth of recession to calculate the percentage of root coverage of this technique. On the other hand, a literature review was carried out based on the following PICO question: P (patients with single gingival recessions in mandibular anterior teeth), I (laterally closed tunnel technique with connective tissue graft),C (coronal advancement flap technique),O (analysing probing depth, recession depth, clinical attachment level, width of keratinised tissue, gingival thickness,average root coverage and complete root coverage). Results: In the case series a mean root coverage of 96.67% ± 8.17 % was obtained, this result being statistically significant. The same was true for the reduction in recession depth (p=0.001), clinical attachment level (p=0.003) and the gain in keratinised tissue width (p=0.001) and gingival thickness (p<0.001). The reduction in probing depth was not significant. In terms of the systematic review, it was found that probing depth was greater in the coronal advancement flap technique, while better gains in keratinised tissue width were obtained with the laterally closed tunnel technique. Conclusions: The laterally closed tunnel technique...(AU)

An online survey of the Spanish Lupus Patient Association (FELUPUS): patient perceptions and experiences.

OBJECTIVES: A survey conducted by the Spanish Lupus Federation (FELUPUS) shows the results on perceptions and experiences of the people who live with lupus in Spain. The information was gathered anonymously from May 21st to June 30th, 2020. The aim of the study was to monitor the impact of the disease on quality of life, as well as to measure the impact of organ damage in lupus patients. METHODS: A national survey was conducted among people with lupus living in Spain who belong to the Spanish Lupus Patient Association (FELUPUS). Online interviews of approximately 25 min were completed. The information was gathered anonymously from May 21st to June 30th, 2020. RESULTS: One thousand two hundred sixty-three interviews were completed. 92% had a diagnosis of Systemic Lupus Erythematosus (SLE) and 8% of Cutaneous Lupus Erythematosus (CLE); 95% of the patients surveyed were female. Most of the patients claimed they stay up late, exercising and work/study were the most limited actions due to the disease. 73% of patients considered that there was little knowledge of the disease by society and at the time of diagnosis, the patient's level of knowledge about lupus was low in 92% of them. Regarding organ damage, many patients did not understand the concept of chronicity and irreversibility of the term, relating it erroneously to acute symptoms like fatigue (38%), joint pain (47%) and even to the presence of cutaneous symptoms such as the presence of oral ulcers (17%). CONCLUSIONS: The survey highlighted the need for disease awareness campaigns, greater involvement of healthcare professionals and the need to provide more information to lupus patients from the time of diagnosis. Nationally and to our knowledge, this is the survey with the largest number of participants (N = 1263) conducted in patients with lupus. Key Points •A national survey was conducted among people with lupus living in Spain and belonging to patient associations in Spain (FELUPUS). •Nationally and to our knowledge, this is the survey with the largest number of participants (N = 1263) conducted in patients with lupus. •Most of the patients claimed they stay up late, exercising and work/study were the most limited actions due to the disease. •73% of patients considered that there is little knowledge of the disease by society and at the time of diagnosis, the patient's level of knowledge about lupus was low in 92% of them.

Preliminary results of customized bone graft made by robocasting hydroxyapatite and tricalcium phosphates for oral surgery.

OBJECTIVE: The objective of this study was to assess the mechanical characteristics and the clinical usefulness of beta-tricalcium phosphate (ß-TCP) and hydroxyapatite (HA) bioblocks grafted in edentulous jaws of 12 patients. METHODS: The scaffolds were produced by robocasting ceramic inks containing 80%/20% ß-TCP and HA, respectively, with an overall porosity of 60%, with a macropore size between 300 and 500 µm. The mechanical performance of cylindrical vs conical specimens was compared using a universal testing machine. The clinical study was performed on 12 edentulous patients who received 4 cylindrical bone bioblocks. After 10 to 16 weeks of osseointegration, the bioblocks were explanted with trephine for histologic analysis by Goldner and Von Kossa staining. RESULTS: Conical shapes were significantly stronger (96.4 ± 8.7 MPa) than cylindrical shapes (87.8 ± 12.2 MPa). The overall degree of porosity ranged from 53.4% to 58.1% in the coronal region to 62.5% to 66.9% at the apex. After the maturation period, 41 valid bioblocks (85.4%) were obtained for histologic study. Bone showing some cellularity was found in 68.4% of the samples, indicating biologically active bone, and adequate calcification was found in 31.7% of the samples. In terms of biomaterial degradation, 73.2% of the samples were completely resorbed or showed significant resorption. CONCLUSIONS: The 80%/20% ß-TCP and HA grafts customized by robocasting appear adequate for regenerating self-contained defects.

Effectiveness of biomolecule-based bioactive surfaces, on os-seointegration of titanium dental implants: A systematic review and meta-analysis of in vivo studies.

Titanium and alloy osseointegrated implants are used to replace missing teeth; however, some fail and are removed. Modifications of the implant surface with biologically active substances have been proposed. MEDLINE [via Pubmed], Embase and Web of Science were searched with the terms "titanium dental implants", "surface properties", "bioactive surface modifications", "biomolecules", "BMP", "antibacterial agent", "peptide", "collagen", "grown factor", "osseointegration", "bone apposition", "osteogenic", "osteogenesis", "new bone formation", "bone to implant contact", "bone regeneration" and "in vivo studies", until May 2022. A total of 10,697 references were iden-tified and 26 were included to analyze 1,109 implants, with follow-ups from 2 to 84 weeks. The ARRIVE guidelines and the SYRCLE tool were used to evaluate the methodology and scientific evidence. A meta-analysis was performed (RevMan 2020 software, Cochane Collaboration) with random effects that evaluated BIC at 4 weeks, with subgroups for the different coatings. The heterogeneity of the pooled studies was very high (95% CI, I2 = 99%). The subgroup of BMPs was the most favorable to coating. Surface modification of Ti implants by organic bioactive molecules seems to favor osseointegration in the early stages of healing, but long-term studies are necessary to corroborate the results of the experimental studies.

Histologic Outcomes of the Use of Different Biomaterials for Socket Regeneration in Fresh Extraction Sockets: A Split-Mouth Randomized Clinical Trial.

PURPOSE: To analyze the quality of bone regeneration in fresh sockets using four different materials at different time points. MATERIALS AND METHODS: A split-mouth randomized clinical trial was designed to evaluate the histologic and histomorphometric characteristics of 82 fresh sockets from 30 patients. One socket per patient healed spontaneously (control), and at least one fresh socket was grafted with a material chosen randomly from a sealed envelope: plateletrich growth factor (PRGF; n = 20 sites), PRGF + autologous bone (n = 9 sockets), autologous bone (n = 10 sites), or PRGF + demineralized freeze-dried bone allograft (DFDBA; n = 13). Biopsy specimens were taken at different time points divided into three assessment groups: short duration (2 to 4 months), intermediate duration (5 to 6 months), and long duration (7 to 12 months). The histologic findings were assessed to quantify the trabeculae pattern, the degree of mineralization, and the quality of bone regeneration. RESULTS: A total of 26 patients with 73 sockets completed the study. Mineralization after a short duration was found to be significantly higher among sockets treated only with autologous bone (47.3% ± 3.6%) or with PRGF+autologous bone (45.1% ± 13.6%). During the intermediate time point, this difference was not observed; also, the control sites were found to have the highest amount of mineralization (37.7% ± 14.9%). After a long duration of wound healing, the PRGF+DFDBA group had the greatest percentage of mineralized tissue (54.7% ± 28.7%), which was significantly higher than the sites treated only with PRGF (30.0% ± 13.2%). CONCLUSION: From a histologic point of view, the use of autologous graft with or without PRGF seems to be the best strategy for socket regeneration within a short period of time (2 to 4 months). However, the application of PRGF alone inside fresh sockets may interfere with normal bone healing compared with control sites healed spontaneously.

Analysis of the Importance of the Motion Used in the Resistance of Different Mechanical Instrumentation Systems in Endodontics: A Comparative Study.

Aim: The aim of this study was to compare the cyclic fatigue strength of different reciprocating rotary systems depending on the movement used. Methods: Four study groups were analyzed (n = 30): (1) Reciproc®, (2) Reciproc Blue®, (3) Wave One Gold® and (4) Procodile®. Each group was divided into three subgroups according to the motion used: (A) Reflex Dynamic® (n = 10), (B) ReFlex Smart® (n = 10) and (C) conventional reciprocating motion (n = 10). They were used in a dynamic cyclic fatigue prototype until their fracture, and the time was measured in seconds. The results obtained were analyzed with the ANOVA method, and for two-to-two comparisons, the Tukey method and Weibull statistics were used. Results: Procodile ReFlex Smart had the longest time to failure, and statistically significant differences were found between Procodile ReFlex Smart and the other files and motions (p < 0.05). Conclusion: Smart motions increase cyclic fatigue strength. ReFlex Smart® motion increases the cyclic fatigue strength of reciprocating rotary systems, and Procodile® ReFlex Smart was the most resistant system file.

Double Lateral Sliding Bridge Flap versus Laterally Closed Tunnel for the Treatment of Single Recessions in the Mandibular Anterior Teeth: A Pseudorandomized Clinical Trial.

(1) Background: This study compared the clinical and esthetic results of the double lateral sliding bridge flap (DLSBF) and the laterally closed tunnel (LCT) techniques, with a subepithelial connective tissue graft (SCTG), for the treatment of single Miller class II-III recessions in the mandibular anterior teeth. (2) Methods: This pseudorandomized clinical trial evaluated 14 patients, 7 of whom were part of the DLSBF + SCTG group, with an average follow-up of 58.7 ± 24.0 months, and 7 of whom were in the LCT + SCTG group, with an average follow-up of 16.7 ± 3.3 months. Clinical and esthetic evaluations of the following parameters were performed and the results for the two groups were compared: gingival recession depth, probing depth, keratinized tissue width, gingival thickness, percentage of root coverage and root coverage esthetic score. (3) Results: After the follow-up period, each technique provided evidence of a reduction in recession depth and clinical attachment level, as well as increased keratinized tissue width and gingival thickness, with statistically significant differences (p < 0.05). The analysis showed that gingival recession depth decreased less in the DLSBF group (4.3 ± 1.2 mm to 0.6 ± 1.1 mm) than it did in the LCT group (4.9 ± 1.1 mm to 0.1 ± 0.4 mm), but no significant difference was found between the two groups. Similarly, a greater reduction in the clinical attachment level parameter was observed in the LCT group, while a greater increase in gingival thickness was observed in the DLSBF group. The presence of scars was the only parameter for which statistically significant differences (p < 0.05) between the two study groups were found. (4) Conclusions: Within the limitations of the study, it indicates that the LCT + SCTG technique may be considered an optimal technique in terms of reducing gingival recession depth, complete root coverage and esthetic results for the treatment of single gingival recessions in the mandibular anterior teeth.

Maxillary reconstruction with subperiosteal implants in a cancer patient: A one-year follow-up.

Introduction: To describe a clinical case on cancer patient with ablative tumor surgery, from treatment planning, surgical resection and subsequent implantological rehabilitation. Case Report: A 61-year-old male, diagnosed with a squamous cell carcinoma in the maxilla, requires the removal of the lesion and corresponding oral rehabilitation. However, two surgeries were necessary to rehabilitate the upper jaw. A custom-made prosthesis was fabricated. It was made from sintered titanium using machined subperiosteal implants with a universal external connection. Finally, a milled cobalt- chrome structure was produced and a feldspar ceramic covering was subsequently applied. Conclusions: Rehabilitation using subperiosteal implants may be an alternative tool for complex surgery involving large atrophies or cancer patients who have undergone highly ablative surgery. Key words:Oral rehabilitation, oral cancer, subperiostal implants.

3D Master Toothguide Is Adequate to Subjective Shade Selection?

Background and Objectives: To study the validity and the degree of representability of the toothguide 3D Master, with 26 physically shade tabs, on the natural tooth colour on a sample of the Spanish population. Materials and Methods: Natural tooth colour was measured in a sample of 1361 Spanish participants of both genders distributed within an age range of 18 and 89 years of age. The colour coordinates were calculated and the frequency of the 26 physically shade tabs of the toothguide as well as the "intermediate shades" (without physical representation in toothguide) through the Easyshade Compact (Vita-Zahnfabrik) spectrophotometer using the 3D Master System nomenclature. The colour differences between the "intermediate shades" were calculated using the Euclidean formula (ΔEab*). The program used for the present descriptive statistical analysis of the results was SAS 9.1.3. Results: A total of 49 "intermediate shades" were registered in 816 participants (60%). The colour coordinates of the 49 'intermediate shades' cover colour coordinates ranging from 0M1.5 (L* 100.0, C* 7.70, h* 112.2) to 5M2.5 (L* 56.8, C* 35.8, h* 78.5). Not all possible 3D Master System's "intermediate shades" were registered in the population studied. 82.4% of the colour differences among the "intermediate shades" were clinically unacceptable (ΔEab* ≥ 5.5 units). Conclusions: Only 40% of the population studied presented a natural tooth colour belonging to the 3D Master Toothguide's physical shade tabs.

Patient-Centered Treatment Outcomes with Full-Arch PEEK Rehabilitation Supported on Four Immediate or Conventionally Loaded Implants. A Randomized Clinical Trial.

This study aims to assess the treatment outcomes (functional and subjective) of full-arch fixed hybrid rehabilitations made of PEEK (poly-ether-ether-ketone) with milled crowns of nano-filled composite (NFC) supported on four to six implants. In this randomized clinical trial, 34 edentate patients in the upper and/or the lower jaws were treated with the fixed hybrid dentures. In 16 patients (47.1% of the sample), the implants were loaded immediately (IL) by means of a provisional fixed rehabilitation made of PMMA (polymethylmethacrylate) screwed on Multi-Unit (MU) abutments connected after emplacement of the implant; however, in the counterparts (n = 18) these MU abutments were covered by healing caps and were left unloaded during two months (conventional loading protocol-CL), when all patients received a fixed hybrid PEEK-NFC rehabilitation on the upper and/or the lower jaw. Treatment outcomes were assessed 12 months after prostheses delivery. Functional outcomes were calculated according to masticatory performance, estimated by mixing ability tests of two colored chewing gums after ten chewing strokes, by the occlusal force/area recorded by pressure-sensitive sheets, and by electromyography of masseters and temporal muscles at maximum biteforce. The subjective outcomes of the treatment were assessed using both the oral satisfaction scale (visual analog scale) and the Spanish version of the Oral Health Impact Profile (OHIP-20). The findings of the present study showed that treatment with fixed PEEK-NFC hybrid prostheses significantly improved the masticatory performance, bite force, occlusal pattern, quality of life, and satisfaction, with the IL group being those with significantly higher occlusal bite forces and greater satisfaction in comparison with CL group. It should be concluded that PEEK-NFC hybrid prostheses can improve several patient-centered outcomes and that loading protocol significantly affects the patient's self-rated satisfaction.

Functional and Patient-Centered Treatment Outcomes with Mandibular Overdentures Retained by Two Immediate or Conventionally Loaded Implants: A Randomized Clinical Trial.

This study aims to assess the treatment outcomes (functional and subjective) of mandibular overdentures retained on two implants with or without an immediate loading protocol. In this randomized clinical trial, twenty fully edentulous patients were treated with a mandibular two-implant-retained overdenture and a complete new maxillary denture. In half of the sample, the implants were loaded immediately by means of VulkanLoc® abutments after emplacement of the implant, but in the counterparts, these VulkanLoc® abutments were connected to implants two months after the surgery (conventional protocol), and until that time the dentures were retained by healing abutments. Treatment outcomes were assessed at two, six, and twelve months after surgery. Functional outcomes were calculated according to masticatory performance, estimated by the mixed fraction of a two-coloured chewing gum after five, ten, and fifteen chewing strokes, by the occlusal force recorded by pressure-sensitive sheets, and by the bioelectrical muscular activity. The subjective outcomes of the treatment were assessed using both the oral satisfaction scale (visual analogue scale) and the Spanish version of the Oral Health Impact Profile (OHIP-20). The findings of the present study show that new complete dentures resulted in significant improvements in chewing ability, patient satisfaction, and oral health-related quality of life and that subsequent implant-retained overdentures produced further and faster significant improvements. The loading protocol may influence those positive self-reported outcomes rather than the objective functional evaluations.

Main 3D Manufacturing Techniques for Customized Bone Substitutes. A Systematic Review.

Clinicians should be aware of the main methods and materials to face the challenge of bone shortage by manufacturing customized grafts, in order to repair defects. This study aims to carry out a bibliographic review of the existing methods to manufacture customized bone scaffolds through 3D technology and to identify their current situation based on the published papers. A literature search was carried out using "3D scaffold", "bone regeneration", "robocasting" and "3D printing" as descriptors. This search strategy was performed on PubMed (MEDLINE), Scopus and Cochrane Library, but also by hand search in relevant journals and throughout the selected papers. All the papers focusing on techniques for manufacturing customized bone scaffolds were reviewed. The 62 articles identified described 14 techniques (4 subtraction + 10 addition techniques). Scaffold fabrication techniques can be also be classified according to the time at which they are developed, into Conventional techniques and Solid Freeform Fabrication techniques. The conventional techniques are unable to control the architecture of the pore and the pore interconnection. However, current Solid Freeform Fabrication techniques allow individualizing and generating complex geometries of porosity. To conclude, currently SLA (Stereolithography), Robocasting and FDM (Fused deposition modeling) are promising options in customized bone regeneration.