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Objective: To evaluate the effect of the activation mode of adhesive cementation on push-out bond strength of fiber-reinforced resin posts to root canal dentin. Method and Materials: Forty mandibular premolars were endodontically treated and randomly divided into 4 equal groups. In groups G-1, G-2, and G-3, Single Bond (3M Espe) was applied and light polymerized for 20 seconds; in group G-4, Scotchbond Multi-Purpose Plus (3M Espe) was used as an autopolymerized adhesive. The dual-cure resin cement Rely X ARC (3M Espe) was light polymerized in G-2 and G-3 but not in G-1 and G-4. The translucent post Light-Post (Bisco) was used in G-3 and the opaque post Aestheti-Plus (Bisco) in the other groups. The roots were sectioned in 3 parts (cervical, middle, apical); each slice was submitted to the push-out test at a crosshead speed of 0.5 mm/min. Data were analyzed by analysis of variance and Tukey test (alpha = .05). Results: Light polymerization of both the adhesive and resin cement in G-2 led to significantly higher bond strength than in G-1, where only the adhesive was light polymerized. No difference was found between G-2 (opaque post) and G-3 (translucent post). The autopolymerized adhesive showed the highest bond strength in all root regions. The middle and apical post/root regions had similar bond strength, but it was significantly lower than that in the cervical region (P < .001). Conclusion: Bond strength to root dentin varied as a function of the activation mode of post adhesive cementation and post/root regions [ABSTRACT FROM AUTHOR]

This in situ study evaluated the Shore A hardness and phthalate concentration of 3 tissue conditioners (Coe-Comfort, Dura Conditioner, Softone) inserted into grooves on 9 maxillary dentures. Data were collected at baseline and after 3, 7, and 14 days of denture use. All materials showed a decrease in phthalate concentration and an increase in hardness over time, but the largest changes occurred during the first 3 days; 59% to 74% of the hardness variability was explained by the phthalate concentration. Overall, Coe-Comfort was softer and had less alteration in its phthalate concentration than Dura Conditioner and Softone up to day 7. [ABSTRACT FROM AUTHOR]

Purpose: To assess the magnitude and distribution of axial forces and bending moments in abutments as a function of cantilever length and inclination of implants. Methods: Ten metallic bars simulated frameworks of fixed implant-supported prosthesis over two master models with five implants: one with all implants straight and parallel (n=5) and one with the two distal implants tilted (n=5). Strain gauges were fixed on abutments to measure deformation when a 50N-load was applied on the cantilever at 10, 15, and 20 mm-distance from the distal abutment. Deformation values were transformed into axial force and bending moment and analyzed by ANOVA and Tukey test ([alpha] = 5%). Results: Comparing 10 mm- to 20 mm-cantilever, there was an increase of approximately 50% for axial force and of 70% for saggital bending moment. On the abutment adjacent to the cantilever, the axial force in the inclined model was 70% lower than in the straight model, and bending moments did not vary. Conclusion: The results suggest that the inclination of distal implants does not have any deleterious biomechanical effect on abutments of the tested models and may reduce the cantilever effect on force magnitude. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the cumulative effect of two protocols of microwave disinfection (Protocol 1: 690 W/6 min; Protocol 2: 345 W/6 min) on surface roughness (Ra) and baseplate adaptation of two denture resins polymerized by microwave energy (Onda Cryl) or hot water bath (QC-20). Methods: For Ra evaluation, rectangular specimens were fabricated and subjected to the following disinfection treatment (n=8/group): 1) Control (no disinfection), 2) Protocol 1, and 3) Protocol 2. Ra was measured using a profilometer at baseline (T0) and after two disinfection procedures (T1, T2) with a 7-day interval immersed in distilled water. To evaluate dimensional stability, maxillary baseplates were divided into the disinfection treatment groups (n=6), and adaptation was measured by weighing a silicon film reproducing the gap between resin baseplate and a metallic master model. Results: Ra had a significant interaction between type of resin/polymerization technique, disinfection treatment, and number of disinfection procedures (P<0.001). For Ra, Protocol 2 and control groups had similar increase of Ra over time, but Protocol 1 groups showed a significant decrease of Ra in T2. Baseplate adaptation was affected by a significant interaction between disinfection treatment and number of disinfection procedures (P<0.001), and Protocol 1 yielded the largest mean in T2. Conclusion: Onda Cryl displayed greater changes of Ra and adaptation than QC-20. Protocol 1 promoted overall damage to both types of denture resins after two disinfection procedures. [ABSTRACT FROM AUTHOR]

Objective: This scoping review aimed to map the adverse reactions in the oral mucosa and face caused by the use of natural products. Methodology: This review was performed according to the Joanna Briggs Institute Manual for Evidence Synthesis and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines, with a protocol registered in the Open Science Framework (DOI 10.17605/OSF.IO/R57D8). The search was carried out systematically using PubMed, Scopus, Web of Science, Embase, LILACS, and LIVIVO databases, as well as gray literature through Google Scholar and OpenGrey. Reports of clinical cases on the adverse effects of natural products on the oral mucosa or perioral region of the face resulted from inappropriate use or self-medication were included. Data from the included studies were described in a narrative form. Results: Seven hundred and six studies were identified, and after removing duplicates and applying the eligibility criteria, 28 studies were included. The year of publication ranged from 1976 to 2022. The studies were conducted in 19 countries. Fifty patients were mentioned in the included studies and 34 were female (68%). The natural products most related to adverse reactions were propolis ( n  = 17), with manifestations such as perioral eczema, edema, erosions, erythema, allergic contact dermatitis, and garlic ( n  = 9), with manifestations such as chemical burn, burning sensation, vesicles and blisters, crusts, and ulcerations. Conclusion: Propolis and garlic were the natural products with the most reported adverse effects on the oral mucosa and perioral region.

Medicinal plants and herbal medicines are used as integrative and complementary practices to provide comprehensive care, disease prevention, health promotion, and to improve quality of life (QoL). This scoping review aimed to identify and describe the use of phytotherapy in oral health care by adults and their outcomes, with a focus on perceptions of oral health-related QoL, healthcare access, and costs. A systematic search was conducted in six databases and supplemented in grey literature. According to a PRISMA-ScR protocol and eligibility criteria, publications were assessed for final inclusion, data charting, and narrative synthesis. Out of 4124 records, 542 publications were selected for full-text reading. A total of 32 studies were included: 21 studies assessed QoL, 7 reported access issues, and 11 reported costs issues. Herbal mouthwashes to prevent or treat non-infectious oral conditions were the most frequent treatment. Efficacy of phytotherapy was usually better than placebo or control treatment. Most studies reported QoL improvement, but several instruments were used with heterogeneous results. Limited healthcare access and high costs favoured traditional folk herbal medicine in underserved populations. It can be concluded that phytotherapy for oral health is used by adults worldwide, following modern clinical pharmacology and traditional knowledge concepts. Further studies should incorporate assessment of QoL, access, and costs in addition to clinical efficacy and safety, which are complementary aspects for delivering a comprehensive and efficient health care for all people., (© 2024 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V.)

Introduction: Long-term clinical success of non-splinted, posterior, and short implants still is unclear. This prospective cohort study reports the 10-year follow-up of 6-mm implants supporting single crowns in the posterior region, and patient-reported outcomes., Methods: Baseline sample comprised 20 patients treated with 46 screw-retained crowns supported by 6-mm implants with moderately rough implant surface. Participants were recalled for a 10-year clinical follow-up to assess survival rates, biologic and mechanic conditions, quality of life (OHIP-14), and treatment satisfaction. Data were collected with clinical-radiographic exams and analyzed using descriptive and inferential statistics., Results: Fourteen patients with 35 implant-crown units were examined after 127.6 ± 11.8 months. For the entire cohort period, 7/46 implants were lost (survival estimate: 77.7% at 133 months), and mechanic complications occurred in 14/46 units (survival estimate: 66.4% at 116 months). In the Cox models, "maximum occlusal force" had a significant effect for implant loss (p = 0.038) and for prosthetic screw loosening (p = 0.038); "arch" and "bruxism" were not significant. Peri-implant bone loss was 0.4 ± 0.6 mm at 10 years. For peri-implant bone level, "crown-to-implant ratio" (p < 0.001) and "time" (p = 0.001) were significant. Bone levels differed from baseline to 12, 48, and 120 months. Satisfaction VAS was 94.0 ± 7.9 mm and OHIP-14 was 2.3 ± 2.2., Conclusion: Single screw-retained crowns supported by 6-mm implants have an acceptable long-term clinical performance, with stable peri-implant bone levels after 10 years of function., (© 2023 Wiley Periodicals LLC.)

Herbal medicine is widely used as an integrative complementary treatment for common chronic diseases, yet potential risks include adverse effects and coprescription., Aim: This exploratory survey assessed Brazilian dentists' knowledge, attitudes, and practices regarding phytotherapy., Material and Method: This study used a consecutive sample of registered dentists who were active in clinical practice and attending advanced training for complex oral rehabilitation at a leading dental school in Latin America. Participants responded to a semi-structured 38-item instrument designed to collect data on sociodemographic, professional and health variables, and on their knowledge, use, prescription and opinions of phytotherapy. Quantitative data were analyzed with descriptive and inferential statistics. Qualitative data were described and analyzed with a thematic approach., Results: A total 53 dentists responded the survey (88.3% response rate). Six dentists reported formal education in phytotherapy and 33 had informal knowledge. Twenty-one dentists (39.6%) reported using herbal medicine, and 17 (32.1%) prescribed phytotherapy to their patients, mostly traditional medicinal plants. A logistic regression model showed that post-graduate degree and personal use of phytotherapy were associated with phytotherapy prescription. Opinions on how to improve the rational use of phytotherapy included the need for research evidence, specific academic education, and knowledge dissemination to clinicians. As a clinical recommendation, it was proposed that questions on herbal medicine should be asked during the dental patient's anamnesis., Conclusions: Dentists with post-graduate degrees and personal use of phytotherapy prescribe herbal medicines for their patients in real-world clinics, regardless of formal education on the subject. Qualitative findings indicate the need to implement scientific initiatives., Competing Interests: The authors declare no potential conflicts of interest regarding the research, authorship, and/or publication of this article.

This article aims to review the status, challenges, and directions of environmentally sustainable oral healthcare by focusing on the dental materials and procedures used in prosthodontics. Sustainable development is a global priority and requires a systemic, integrative approach from all sectors of society. The oral healthcare sector is responsible for substantial greenhouse emissions throughout its value chain, including raw material extraction, industrial production, supply distribution, clinical practice, and management of waste. Of all dental specialties, prosthodontics has been one of the main generators of carbon emissions by fabricating a single product such as dentures or crowns in multiple steps. Dental prosthetic procedures involve chemicals and materials such as polymers, ceramics, metals, gypsum, and wax, which are often used in large quantities and for a single use. Thus, environmental risks and socioeconomic burdens can result from residuals and improper disposal, as well as waste and the embedded costs of unused materials retained by manufacturers, retail suppliers, dental laboratories, and dental clinics. To mitigate the environmental impact generated by conventional prosthodontics, we urge awareness and the adoption of sustainable good practices in the daily routine of dental clinics and laboratories. Capacity building and investment in a circular economy and digital technology can reduce the carbon footprint of prosthetic dentistry and improve the quality of life for present and future generations., (Copyright © 2023. Published by Elsevier Inc.)

Purpose: Implant-supported fixed complete dentures (IFCD) experience failures and complications related to biological and technical risk factors. This study investigated the effect of biomechanical variables of IFCD on 1-year peri-implant bone loss at the buccal, palatal/lingual, mesial, and distal implant sides. A new method was used to measure the geometric biomechanical variables of IFCD using cone beam computed tomography (CBCT)., Methods: The study sample consisted of 246 external hexagon implants supporting 48 hybrid IFCD in 44 patients. CBCT images obtained immediately (T0) and 1 year (T1) after prosthesis installation were used to measure the support polygon area, clinical crown/implant (C/I) ratio (vertical lever), anteroposterior power and resistance arms, anterior and posterior cantilevers (horizontal levers), and peri-implant bone remodeling (T1-T0). Data were analyzed using multilevel multivariable models., Results: The average total bone loss in the mandible and maxilla were 0.88 mm, with a loss of 0.62 mm in the mandible and 1.08 mm in the maxilla. The C/I ratio had a significant effect on bone loss on the mesial, distal, and palatal/lingual sides (P <.05). The anterior cantilever had a protective effect on the lingual side of the anterior implant. No effect on bone loss was found for the support polygon area, posterior cantilever, resistance arm, or power arm (P >.05)., Conclusions: The results suggest that the C/I ratio and anterior cantilever in IFCD affect peri-implant bone loss according to the implant side and position in the arch.

Background: Patients with temporomandibular disorder (TMD) often have orofacial pain and may use medication without professional prescription. Self-medication and inappropriate drug intake may cause serious health problems. This cross-sectional study evaluated the self-medication profile of TMD patients, the most used medications and their effect, and the relation between self-medication and socioeconomic factors., Methods: A non-representative sample (n=358) consisted of consecutive adult patients seeking TMD treatment in specialized referral centers for orofacial pain of two universities in São Paulo city, Brazil. A standardized questionnaire was used to collect the study variables before the TMD treatment: self-medication history, TMD pain intensity, sex, age, ethnicity, marital status, schooling and socioeconomic levels. Data were analyzed by descriptive statistics, chi-square test, and logistic regression models at the 0.05 significance level., Results: Almost 60% of 358 TMD patients reported self-medication. Patients with severe TMD were 4.7 times more likely to self-medicate when compared to patients with low TMD intensity (O=5.7; 95% CI=2.4; 13.3; P =0.043), as well as female patients were 30% more likely to self-medicate compared to male patients (OR=2.3; 95% CI=1.1; 5.1; P <0.001). The other independent variables were not associated with self-medication. The frequencies of moderate and severe TMD in women were larger than in those in men ( P <0.001). Analgesics and anti-inflammatory drugs were the most used medications. Regarding medication efficacy, 82% of patients reported some improvement after use, but 9% reported side-effect sickness., Conclusion: Self-medication is common among TMD patients attending specialized clinics, and this inappropriate practice is more likely to occur in women and in patients with severe signs and symptoms of TMD., Competing Interests: Conflict of interest The authors declare that there is no conflict of interest., (Copyright © 2022 Campos et al. Published by Tehran University of Medical Sciences.)

Objectives: This study evaluated hyaluronic acids (HA) with different molecular weights as potential matrices for tissue-engineered bone grafting and their possible influence on the paracrine mechanisms of adipose-derived mesenchymal stromal cells., Material and Methods: Murine adipose mesenchymal stromal cells (mASCs) on the fourth passage were seeded in 96-well plates, osteoinduced for 27 days and exposed for 3 days to low (HA-LW) and high/low molecular weight (HA-HLW) at previously defined concentrations. Cytokines IGF-1, VEGF, FGF-2, and BMP-2 were evaluated by quantification in the supernatant., Results: Greater expression of growth factors was observed in groups with HA-HLW compared to HA-LW. Results indicated that differentiated cells secreted fewer cytokines, namely VEGF, FGF, and BMP-2 than undifferentiated mASCs (p < 0.05). IGF-1 showed its greatest expression in the mASC HA-LW group (p < 0.05)., Conclusions: The application of HA-HLW as cell matrix in tissue engineering did not compromise mASC paracrine effect. Also, the association of HA-HLW matrix and mASCs resulted in greater expression of osteogenic growth factors. Longer periods of cell differentiation seemed to negatively affect their capacity for local paracrine stimulation., Clinical Relevance: The use of HA-HLW as matrix for undifferentiated ASCs can be positive for bone regeneration, favoring its application as cell matrix in bone grafting procedures., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Purpose: This intra-patient retrospective study of up to 10 years evaluated the clinical success and risk factors of 6- and 8-mm long implants and their respective prostheses., Materials and Methods: The sample consisted of patients treated at a Military Polyclinic dental service, who received both 6- and 8-mm long tissue level implants in the posterior region of the same arch. Data were collected from the dental charts, clinical and radiographic exams, self-report of sleep bruxism, measurement of maximum occlusal force, and clinical crown-to-implant (C/I) ratio. Data were analyzed by descriptive and inferential statistics with univariate and hierarchical multivariate models, at the 0.05 significance level., Results: The 30 patients (27 women) had 85 implants and 83 prostheses. Two implants were lost before prosthesis installation (implant survival: 97.6%). Ten events of prosthetic complication (screw tightening loss) occurred in five patients (success rate: 87.9%) in a single moment. Only the variable C/I ratio had a significant effect for repairable prosthesis complication ( P <.05)., Conclusion: The results suggest that 6- and 8-mm long implants have similar long-term clinical success for implants and prostheses., (© 2021 The Korean Academy of Prosthodontics.)

Background: Bone tissues may undergo remodeling under functional mechanical stimuli., Purpose: This prospective study on implant-supported fixed complete dentures (IFCDs) evaluated the radiographic trabecular bone changes in density by means of gray levels and texture analysis variables after up to 3-year loading., Materials and Methods: The sample consisted of digital periapical radiographs of 63 distal implants of hybrid IFCDs installed in 30 patients (22 women, mean age of 62 ± 7.8 years). Digital periapical radiographs were taken after prosthesis installation, and 1 and 3 years after IFCD loading. Longitudinal images of each implant were superimposed, and the same regions of interest were selected for measurement of gray levels statistics (mean gray levels, SD, and coefficient of variation [CV]) and texture parameters (correlation, contrast, entropy, and angular second moment). Data were analyzed by mixed regression models., Results: Mean gray levels increased for 1 year (P < .05), for 3 years (P < .01) and for maximum bite force (P < .01). The interaction between bruxism and time in 1 year was significant (P < .01) for a decrease in CV. No significant effect of texture analysis variables was found (P > .05)., Conclusions: The results suggest an increase of radiographic bone density as measured by an increase in mean gray levels and a decrease in CV in IFCD distal implants up to 3 years of loading., (© 2019 Wiley Periodicals, Inc.)

Occlusal support may influence muscular function during complex motor tasks. This study evaluated the duration and sequence of muscular activation of masticatory (temporal, masseter), postural head/neck (sternocleidomastoid, trapezius), postural trunk (rectus abdominis, paravertebrals), and low extremity strength (rectus femoris, gastrocnemius) muscles during simulation of activities of daily living (ADL) in edentulous women wearing complete dentures (n = 10) and in dentate women (n = 10). Electromyographic activity was recorded during tests of stand-up/sit down in the Chair, sit up/lie down in the Bed and lift/lower Bags. Occlusal support (dentures) had a significant effect on duration of muscular activation in the Chair Test: the masseter muscle activated longer with dentures during the standing movement. The masseter and sternocleidomastoid muscles showed significant alteration in their order of activation in non-denture-wearing women. For the Bed Test, dentures had significant effect for the gastrocnemius during the sitting-up phase and for the rectus abdominis during the lying-down movement. For the Bag Test, head/neck muscles were activated in a different order as a function of occlusal support. Anticipation of activation of the paravertebral muscles, rectus abdominis, and gastrocnemius was observed in dentate women compared with denture wearers. These findings suggest that occlusal support influences electromyographic activity of some muscles during simulation of ADL., (© 2019 Eur J Oral Sci.)

This clinical study evaluated the early effect of oral rehabilitation with dental implants and nocturnal bruxism on maximum occlusal force (MOF), before sensorimotor adaptation. A consecutive sample consisted of 127 patients divided into three groups according to their dental state: G1- implant-supported fixed complete denture (IFCD) opposing to a small fixed prosthesis or natural dentition; G2- IFCD opposing to a complete denture; and G3- small fixed prosthesis or natural dentition in both arches. Clinical data were collected after prosthesis installation: systemic and oral health conditions, MOF, self-reported bruxism, and bruxism severity (low, moderate, severe). Data were analysed by ANOVA and Tukey-Krammer tests. Dental state and the interaction sex-bruxism had significant effect on MOF. G1 had higher MOF than G3, but G2 was not significantly different from G1 and G3. Men with bruxism had the highest MOF. The levels of bruxism severity did not have a significant effect on MOF. The results suggest that MOF varies as a function of dental state and the interaction sex-bruxism. However, presence and severity of bruxism alone does not affect MOF., (Copyright© 2019 Dennis Barber Ltd.)

The impact of oral rehabilitation on masticatory function and oral health-related quality of life (OHRQoL) may vary with the experience of the individual with tissue loss. Our hypothesis is that patient-centered outcomes vary among adults who have experienced large defects in the maxilla due to congenital or acquired conditions even after oral rehabilitation to restore aesthetics and function. This study compared OHRQoL, perceived masticatory ability, maximum bite force (MBF), and symptoms of pain and depression among subjects with acquired (edentulous maxilla) and congenital (cleft lip and palate) loss of oral tissues in the maxilla after dental treatment. A gender-matched sample (n = 60) of cleft lip and palate (CLP), maxillary denture wearers (DENT) and controls (CONT) was recruited. OHRQoL was assessed using OHIP-14. Chewing was evaluated through a masticatory ability questionnaire and by MBF. The RDC/TMD Axis II questionnaire was used to assess symptoms of pain and depression. Data were analyzed by Fisher's test, Kruskal Wallis test, and Spearman correlation coefficients. CLP showed higher OHIP-14 and depression scores than DENT and CONT (p < 0.05). Sub-analysis by OHIP-14 items (%FOVO) showed higher prevalence of psychological impact for CLP and of functional impacts for DENT. The number of foods difficult to chew, of food textures difficult to chew, and avoided foods were similar between CLP and DENT. OHIP-14, MBF, and depression scores showed significant correlation (p < 0.05). The results suggest that adults with treated CLP or maxillary DENT have chewing impairment and lower MBF than healthy subjects, with different psychological and functional impacts.

Objectives: This prospective cohort study estimated the effect of technical and clinical factors on mechanical complications in implant-supported fixed complete dentures (IFCDs). The patient's perception of the impact of oral rehabilitation on quality of life was assessed., Material and Methods: A non-probabilistic sample consisted of 88 consecutive patients treated with 94 screw-retained, metal-acrylic IFCDs. Data collection included sociodemographic variables, presence and intensity of bruxism, maximal occlusal force, opposing arch, design of the metallic framework, distribution of occlusal contacts, and quality of life (OHIP-14). IFCD-level data were analyzed using Kaplan-Meier survival analysis and Cox regression model. Quality of life data were analyzed by paired Student t test., Results: During a mean follow-up of 35.1 ± 18.3 months, 16/94 IFCDs (17%) had repairable mechanical complications because of loosening/fracture of artificial teeth (n = 15) and screw loosening (n = 1). Framework design (retention pins <4 mm) was a significant risk factor for complications (HR = 11.038; p = 0.027) when adjusted for sex. Mechanical complications were not associated with sex, body mass index, thickness of the acrylic resin veneering, type of opposing arch, distribution of occlusal contacts and force, protrusion interference, presence/intensity of bruxism or maximal occlusal force. OHIP-14 total scores decreased after IFCD treatment for both patients with or without complications., Conclusions: Within the limitations of this study, the results suggest that clinical success is associated to framework design with retention pins equal or longer than 4 mm. Quality of life improved with IFCD treatment, even in patients with mechanical complications., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: This prospective cohort study assessed the effect of bone quality on the primary and secondary stability of single short implants placed in the posterior region., Materials and Methods: A total of 39 short implants (4.1 × 6-mm long) were placed in the posterior region of the maxilla or mandible in 18 patients. Bone quality was classified into type I, II, III, or IV as assessed intrasurgically. Primary implant stability was measured with insertion torque, damping capacity (PTV values), and resonance frequency analysis (ISQ values). Secondary stability was measured by ISQ and PTV at abutment installation. Data were analyzed by using repeated-measures ANOVA and Tukey's test, Kruskall-Wallis test, and Spearman correlation tests., Results: Implants placed in bone type IV had significant lower insertion torque and ISQ values as well as higher PTV values than in bone types I to II (P < 0.05). The mean ISQ values were higher at abutment installation than at implant placement (P < 0.05), regardless the bone type. The assessment methods of implant stability showed a moderate correlation., Conclusions: Bone quality influences both the primary and secondary stability of single short implants in the posterior region.

Purpose: To evaluate the influence of cobalt-chromium (Co-Cr) casting alloys' melting temperatures on the cast-to Co-Cr implant cylinders' marginal fit., Materials and Methods: Co-Cr alloys with different melting ranges were cast into 20 Co-Cr cylinders: 10 in a high-melting temperature (HMT) group and 10 in a low-melting temperature (LMT) group. Ten cylinders were used as received as a control group. Cylinders' marginal misfit and dimensional stability were evaluated using scanning electron microscopy (×500)., Results and Conclusion: HMT cylinders showed significant differences in marginal misfit (2.48 ± 1.07 μm 2 ) compared to LMT (1.53 ± 0.37 μm 2 ) and control (1.27 ± 0.57 μm 2 ) cylinders, but there were no differences in dimensional stability. HMT Co-Cr alloys produce implant-supported prostheses with poor marginal fit.

The aim of this study was to analyze the influence of dental implants on the radiographic density of the peri-implant region in tomographic and radiographic examinations. A sample of 21 dental implants from 10 patients with Brånemark-protocol prostheses was evaluated based on postoperative control images, including periapical radiography (paralleling technique), panoramic radiography, and cone beam computed tomography (CBCT). The density means of 6 defined areas near dental implants were calculated and compared considering their locations and the different imaging examinations. The CBCT examinations showed significantly different densities among the measured areas (P < 0.001), while there were no significant differences among the density means of the various areas in periapical radiographs (P = 0.430) and panoramic radiographs (P = 0.149). The highest mean densities were observed in areas closer to the implants in all the examinations: CBCT (127.88 and 120.71), panoramic (106.51 and 106.09), and periapical (120.32). The sagittal CBCT images were measured in 2 different sections, and in both sections those areas closer to implants showed mean densities that were significantly higher than means from more distant areas (P < 0.001). Means from distant areas on CBCT slice imaging were significantly lower than the densities of the same areas on periapical and panoramic examinations. The changes in mean radiographic density values in the peri-implant region confirmed the interference of dental implants in radiographic and tomographic images. CBCT images suffered the greatest interference from dental implants., Competing Interests: Disclaimer: The authors report no conflicts of interest pertaining to any of the products or companies discussed in this article.

Background: The use of short implants is still not a consensus for challenging clinical situations, such as unfavorable crown-to-implant (C/I) ratio., Purpose: This prospective study evaluated the rates of prosthetic complications and implant failure, the mean marginal bone loss of 6-mm dental implants with single crowns in posterior regions and the potential risk factors., Materials and Methods: Forty-six dental implants, 6-mm long and 4.1-mm wide, were placed in the posterior region in 20 patients. Patients were clinically and radiographically examined after the restoration with single crowns and on a yearly basis. Potential risk factors (arch, bruxism, maximum bite force, anatomical and clinical C/I ratios, and occlusal table area) were analyzed according to the following outcomes: implant survival, bone loss, and prosthetic complications., Results: The mean follow-up time was 45 ± 9 (16-57) months. There was no early loss of implants. After prosthetic loading, 4 implants were lost (2 in the mandible and 2 in the maxilla; 91.3% survival), and there were 13 prosthetic complications (28.3%), yielding a 65.2% success rate. The frailty term showed a 95% greater chance of loss in the mandible than the maxilla. Mean peri-implant bone loss was of 0.2 ± 0.4 mm, 0.1 ± 0.2 mm, 0.1 ± 0.3 mm, and 0.2 ± 0.4 mm in the first, second, third, and fourth years, respectively, with a mean cumulative loss of 0.3 ± 0.5 mm at 48 months. In the multilevel model, the effects of the clinical C/I ratio and time were significant for bone loss (P < .001). It was estimated that a mean bone loss of 0.1 mm is associated with both a one-unit increase in time (12 months) and a 0.1 increase in the clinical C/I ratio. The other potential risk factors showed no significant relationship with the outcomes., Conclusions: The 6-mm implants supporting single crowns performed well, but the mandible shows a higher risk of failure. The time and clinical C/I ratio are predictors for bone loss., (© 2017 Wiley Periodicals, Inc.)