Factors influencing living space utilization among older Afro-Colombian adults.

OBJECTIVES: Investigate the factors influencing life space utilization in older Afro-descendant adults residing in Tumaco, Colombia - a marginalized region of the country. DESIGN: This cross-sectional study included 388 Afro-descendant older adults. The study assessed living space using the Life Space Assessment (LSA) scale and collected demographic data. Cognitive levels were measured with the Mini-Mental State Examination (MMSE), and depressive symptoms were assessed using the Yesavage scale. Socio-emotional indicators were determined with the Medical Outcomes Study (MOS). The research employed linear and logistic regression models for data analysis. RESULTS: On average, participants scored 27.0 on the LSA scale. A lack of perceived income resulted in a 10.44-point decrease on the LSA scale. For each unit increase in the MOS-Instrumental Dimension score, the LSA score increased by 0.52 points (95% CI 0.17-0.87). As for cognitive performance (MMSE scale), each one-point increase resulted in a 0.69 decrease in the LSA score (95% CI -1.25 to -0.12). CONCLUSION: Socioeconomic disadvantages limit living space utilization, particularly in the Afro-descendant population. Yet, social support can enhance living space use despite environmental and economic constraints.

Efficacy of microsurgery and comparison to macrosurgery for gingival recession treatment: a systematic review with meta-analysis.

OBJECTIVES: Microsurgical principles, techniques, and armamentarium have made significant contributions to the periodontal plastic surgery. The present meta-analysis aimed to investigate the overall efficacy of microsurgery on root coverage, and its clinical outcomes when compared to traditional macrosurgery. MATERIAL AND METHODS: Electronic searches on PubMed, Embase, and CINAHL were used to retrieve prospective clinical trials. Primary outcomes were the mean root coverage (mRC) and probability of achieving complete root coverage (cRC), with secondary outcomes as other periodontal parameters and patient-reported outcome measures (PROMs). RESULTS: Nineteen studies were included in the quantitative analysis. Microsurgery was estimated to achieve 83.3% mRC and 69.3% cRC. From a subgroup of 9 comparative studies, it was estimated microsurgery increased mRC by 6.6% (p<0.001) and cRC by 27.9% (p<0.01) compared to macrosurgical control treatments. Operating microscope (OM) yielded a significantly 6.7% higher mRC than the control group (p=0.002), while using loupes showed 6.16% increase in mRC with a borderline significance (p=0.09). OM and loupes-only had a 31.05% (p=0.001) and 25.54% (p=0.001) increases in achieving cRC compared to control, respectively. As for PROMs, microsurgery reduced postoperative pain (p<0.001) and enhanced esthetics (p= 0.05). CONCLUSIONS: Microsurgery significantly improved mean root coverage, probability of achieving complete root coverage, esthetics, and post-surgical recovery. Microsurgery enhances not only subclinical healing but also clinical outcomes, possibly owing to its minimally invasive approach and surgical precision. CLINICAL RELEVANCE: Periodontal plastic microsurgery is minimally invasive, inducing less surgical trauma and ultimately resulting in improved clinical outcomes, patient's satisfaction, and quality of life.

Dimensional Variations in the Soft Tissue Profile After Removal of Implant-Supported Fixed Interim Restorations: A Pilot Clinical Study.

PURPOSE: To measure dimensional changes of the periimplant soft tissue profile after removal of a single implant fixed interim restorations using digital impression procedures. MATERIALS AND METHODS: Ten participants presenting with single implant-supported fixed interim restorations (ISFIRs) on the maxillary esthetic zone. A 2-step silicone impression was made of the maxillary arch with the ISFIRs. The experimental procedure was obtained by making digital impressions of the gingival contours immediately after ISFIR removal. The control procedure was formed by fabricating definitive casts from the conventional impression using the ISFIRs as a customized impression transfer and making digital impressions of these definitive casts. Both images of paired groups were digitally overlapped on the computer, and their profiles were measured at the coronal, midlevel gingiva in the buccolingual and mesiodistal width. RESULTS: Statistically significant differences between the ISFIR emergence profile width and the unsupported soft tissue profile width were observed at the midlevel gingiva in the buccolingual dimension (1.35 mm) and at the coronal (0.51 mm) and midlevel gingiva (1.29 mm) in the mesiodistal dimension. CONCLUSIONS: A digital impression, as used in this pilot study, does not capture accurately the desired soft tissue dimensions immediately after removal of the ISFIR.

A randomized, controlled, multicentre clinical trial of post-extraction alveolar ridge preservation.

AIM: To compare the effectiveness of two-ridge preservation treatments. MATERIALS AND METHODS: Forty subjects with extraction sockets exhibiting substantial buccal dehiscences were enrolled and randomized across 10 standardized centres. Treatments were demineralized allograft plus reconstituted and cross-linked collagen membrane (DFDBA + RECXC) or deproteinized bovine bone mineral with collagen plus native, bilayer collagen membrane (DBBMC + NBCM). Socket dimensions were recorded at baseline and 6 months. Wound closure and soft tissue inflammation were followed post-operatively, and biopsies were retrieved for histomorphometric analysis at 6 months. RESULTS: Primary endpoint: at 6 months, extraction socket horizontal measures were significantly greater for DBBMC + NBCM (average 1.76 mm greater, p = 0.0256). Secondary and Exploratory endpoints: (1) lingual and buccal vertical bone changes were not significantly different between the two treatment modalities, (2) histomorphometric % new bone and % new bone + graft were not significantly different, but significantly more graft remnants remained for DBBMC; (3) at 1 month, incision line gaps were significantly greater and more incision lines remained open for DFDBA + RECXC; (4) higher inflammation at 1 week tended to correlate with lower ridge preservation results; and (5) deeper socket morphologies with thinner bony walls correlated with better ridge preservation. Thirty-seven of 40 sites had sufficient ridge dimension for implant placement at 6 months; the remainder were DFDBA + RECXC sites. CONCLUSION: DBBMC + NBCM provided better soft tissue healing and ridge preservation for implant placement. Deeper extraction sockets with higher and more intact bony walls responded more favourably to ridge preservation therapy.

A systematic review of oral wound healing indices.

Wound healing monitoring for abnormality identification and intervention is crucial to securing a successful surgical outcome. Indices have been used to summarize the degree of healing. Given the increasing frequency of regenerative procedures which preserve dentition and implant stability, and the higher esthetic demands, an appraisal of the available indices is needed to identify the current knowledge gap. This study aimed to systematically review published oral wound healing indices and scores. MATERIALS AND METHODS: A complete literature electronic search in 5 databases was conducted by two reviewers. A combination of keywords related to oral wound healing was used. RESULTS: A total of 11 articles were included in the evaluation of various procedures (conventional periodontal procedures, guided tissue regeneration, soft tissue reconstruction procedures, and tooth extractions), at different time points (1 day to 12 weeks), with a focus on diverse clinical signs and symptoms. Frequently evaluated parameters included wound dehiscence/epithelialization (91%), tissue color (redness) (73%), suppuration (55%), swelling/edema (55%), and hemostasis (55%). Other less commonly used parameters include esthetics-related and patient-centered outcomes. CONCLUSION: The available indices evaluate a diverse group of subjective clinical signs and symptoms to estimate the underlying biological healing events and assess the degree of clinical success. The majority of the included indices are not validated. Quantitative and objective subclinical parameters including blood perfusion, biomaterial stability, and completeness of epithelialization, are needed for customized wound healing care and better outcome prediction.

Review of Intraoral Vasculature and Implications on Incision Designs of Periodontal and Implant Surgeries.

Currently, the incision design for periodontal and implant surgeries is mainly based on the surgeon's personal preference. The primary aim of this study is to review the intricate periodontal microvascular system and to illustrate the potential impact of commonly applied flap designs on the integrity of this system. A complete literature electronic search resulted in 37 relevant articles. The maxillary, facial, and lingual arteries supply the microvasculature system, including the supraperiosteal, intraligamental, and intraosseous arterioles. These arterioles have their own territories yet are extensively interconnected. The impact of common papilla management techniques are discussed, including tunneling; papilla base, incision, and preservation; and flap-releasing incisions. Flap design can impact reperfusion and blood inflow in the early healing phase, which eventually influences wound closure probability, healing speed, surgical predictability, tissue volume change, and postoperative morbidity. Future studies on the three-dimensional distribution of microvasculature and clinical impact of various flap designs on tissue reperfusion can lead to evidence-based incision selection and improved wound-healing outcomes.

Anatomy-driven complexity classification for soft-tissue tunneling procedures.

BACKGROUND: The tunnel technique (TUN) preserves the integrity of the papilla by creating envelope flaps that allow for the insertion of a connective tissue graft, and/or biomaterials. METHODS: (1) A comprehensive overview of tunneling flap procedures in the treatment of gingival recessions (GRs) for soft tissue coverage is presented and (2) A classification system for soft and hard tissue anatomy of GR sites which may aid the clinician in determining the surgical complexity is being introduced. RESULTS: A novel clinical classification system is proposed to illustrate complexity levels determined by soft and hard tissue anatomy of GR sites such as the mucogingival junction proximity to the gingival margin, bone morphotype, and mucosal margin thickness. CONCLUSIONS: TUN is highly effective in treating single/multiple GRs. Its limitations are related to variability in surgical site anatomy and operator expertise. A classification system based on anatomical soft and hard tissue variations has been proposed to help identify complexity levels encountered during tunneling procedures. KEY POINTS: Site-related factors directly impact the surgical variables related to tissue trauma, flap tension, soft tissue management, muscle pull, and wound stability during the healing of gingival recessions (GRs). The achievement of expedited and favorable wound healing is crucial to obtaining quantitative and qualitative success in the treatment of GR and the long-term stability of root coverage. A classification system based on anatomical soft and hard tissue variations has been proposed to facilitate tunneling procedures while respecting surgical principles.

Operating microscope-assisted reconstructive strategy for peri-implantitis: A case series report.

BACKGROUND: Treating peri-implantitis with reconstructive means has been largely unpredictable due to access limitations for surface decontamination, unfavorable bony topography, difficulty in achieving wound stability, and inferior soft tissue qualities. A microsurgical approach with the use of the operating microscope (OM) that provides adjustable higher magnification (∼5-30 times) and coaxial illumination, coupled with the use of microsurgical instruments, may overcome, or alleviate some of the abovementioned obstacles, resulting in more predictable outcomes. METHODS: Three patients received reconstructive therapy for correcting peri-implant defects under OM in private practice settings. After precise incisions to preserve soft tissue volume, the flaps were dissected prudently from underlying granulomatous tissues, which were subsequently removed, followed by controlled flap releasing under ∼10-15x magnification. Surface decontamination was performed using a piezoelectric ultrasonic device, air polishing, and hand instruments at ∼30x magnification. The biomaterial selections were dehydrated human de-epithelialized amnion-chorion membrane with mineralized allograft particulates in two cases and xenografts in one case, based on the surgeons' preference. Wound closure followed the non-submerged approach. RESULTS: These cases demonstrated uneventful soft tissue healing, favorable radiographic bone fill, and disease resolution with follow-ups ranging from 2 to 4 years. CONCLUSIONS: Preliminary data suggest encouraging outcomes after the microsurgical approach following biological as well as biomechanical principles for peri-implant defect reconstruction.

Efficacy of a harvest graft substitute for recession coverage and soft tissue volume augmentation: A randomized controlled trial.

BACKGROUND: The autogenous connective tissue graft (CTG) with coronally advanced flap (CTG+CAF) is the "gold standard" for recession defect coverage; however, researchers continue to pursue lower morbidity, more convenient and unlimited supply harvest graft substitutes, including those that could provide soft tissue volume augmentation. METHODS: A randomized, controlled, double-masked comparison of a volume-stable collagen matrix (VCMX) versus CTG was conducted at four clinical investigation sites. Single, contralateral, within patient matched-pair, RT1 recession defects were treated with VCMX+CAF (test) and CTG+CAF (control). The primary efficacy end point was percent root coverage at 6 months. Secondary efficacy end points included clinical measures such as soft tissue volume, attachment level, and keratinized tissue width. Patient-reported outcomes included measures such as discomfort, esthetics, and overall satisfaction; 6-month end point results were followed for 1 year. RESULTS: Thirty patients received control and test therapies, and all patients were available for follow-up measures. Average percent root coverage for CTG+CAF was 90.5% ± 14.87% versus 70.7% ± 28.26% for VCMX+CAF, P <0.0001. Both therapies produced significant soft tissue volume increases (84.8 ± 47.43 mm3 control versus 48.90 ± 35.58 mm3 test, P = 0.0006). The test, harvest graft substitute produced less postoperative pain and was preferred by patients at the 6-month end point. All other end point measures were not significantly different. CONCLUSIONS: VCMX+CAF root coverage was inferior to CTG+CAF but produced less morbidity and was preferred by patients. Case/patient selection and surgical technique appear key to achieving successful results with the harvest graft alternative.

A Prospective, Randomized, Controlled, Multicenter Evaluation of Extraction Socket Management Comparing a Wound Dressing and a Soft Tissue Substitute.

Postextraction bone grafting and implant placement help preserve alveolar bone volume. Collagen wound dressings and soft tissue graft substitutes may help protect extraction socket bone grafts and provide better gingival contours. This randomized, controlled, multicenter, and double-blinded study was conducted to compare a control (wound dressing) and a test (soft tissue graft) substitute in nearly intact extraction sockets. Both test and control sockets were grafted with a xenogeneic bone graft. Graft containment, extraction socket soft tissue gap closure, gingival contour, and gingival thickness were examined over 16 weeks, at which time implants were placed. Healing was uneventful for both groups, and there was no significant difference (P < .05) between the times required to close the extraction socket soft tissue gap (~80% of sites closed by 8 weeks). Bone grafts were covered and contained longer in the test group (~4 weeks vs ~2 weeks), with less contour disruption out to 4 weeks; however, at implant placement, soft tissue contours in both groups were comparable, and soft tissue thicknesses were not significantly different.

American Academy of Periodontology best evidence consensus statement on the use of biologics in clinical practice.

A biologic is a therapeutic agent with biological activity that is administered to achieve an enhanced regenerative or reparative effect. The use of biologics has progressively become a core component of contemporary periodontal practice. However, some questions remain about their safety, indications, and effectiveness in specific clinical scenarios. Given their availability for routine clinical use and the existing amount of related evidence, the goal of this American Academy of Periodontology (AAP) best evidence consensus (BEC) was to provide a state-of-the-art, evidence-based perspective on the therapeutic application of autologous blood-derived products (ABPs), enamel matrix derivative (EMD), recombinant human platelet-derived growth factor BB (rhPDGF-BB), and recombinant human bone morphogenetic protein 2 (rhBMP-2). A panel of experts with extensive knowledge on the science and clinical application of biologics was convened. Three systematic reviews covering the areas of periodontal plastic surgery, treatment of infrabony defects, and alveolar ridge preservation/reconstruction and implant site development were conducted a priori and provided the foundation for the deliberations. The expert panel debated the merits of published data and exchanged experiential information to formulate evidence-based consensus statements and recommendations for clinical practice and future research. Based on an analysis of the current evidence and expert opinion, the panel concluded that the appropriate use of biologics in periodontal practice is generally safe and provides added benefits to conventional treatment approaches. However, therapeutic benefits and risks range based on the specific biologics used as well as patient-related local and systemic factors. Given the limited evidence available for some indications (e.g., gingival augmentation therapy, alveolar ridge preservation/reconstruction, and implant site development), future clinical studies that can expand the knowledge base on the clinical use of biologics in periodontal practice are warranted.

Microscope-Assisted Maxillary Sinus Augmentation: A Case Series.

Minimally invasive microsurgery performed using an operating microscope (OM) has shown accelerated and improved wound healing for periodontal plastic and regenerative procedures. This case series aims to demonstrate the potential usefulness of OM for maxillary sinus augmentation in a private practice setting. Twelve vertical sinus augmentations (VSAs) and 8 lateral sinus augmentations (LSAs) were performed with the assistance of OM. Flap reflection, osteotomy, sinus membrane elevation, membrane integrity evaluation, implant placement (if indicated), and wound approximation with sutures were performed under OM. After a minimum healing period of 6 months, radiographic bone height gain was assessed. One sinus membrane perforation was observed during VSA surgery. The mean vertical bone gain was 4.82 ± 1.31 mm and 8.36 ± 1.45 mm for VSA and LSA, respectively, with 100% implant success rate. OM-assisted maxillary sinus augmentation provides favorable clinical visualization, thus facilitating delicate hard and soft tissue manipulation.

Navicular Syndrome-related changes to collagen proportion of different cross-sections of the flexor tendons in equine distal forelimb.

The aim of this study was to quantify the distribution of aligned and non-aligned collagen in cross-sections of the superficial digital flexor tendon (SDFT) and deep digital flexor tendon (DDFT) in different levels of the distal forelimb of equines diagnosed with NS (Navicular Syndrome). Sixty equine forelimbs were collected. Was compared two groups (NA, Not affected vs. NS-group) by t-Student. Diagnosis of NS was based on clinical and lameness examination, diagnostic analgesia and radiological findings. The proportion of aligned and non-aligned collagens at 2 levels for the SDFT and 3 levels for the DDFT were measured by histochemical stains. The amount of aligned and non-aligned collagen in tendons were calculated using Colour-Based Segmentation function. Regarding collagen, there were significant differences in the amount of aligned collagen (NA: 21.2 ± 1.31; NS-group: 12.2 ± 4.67; p = 0.0026) and non-aligned collagen (NA: 21.8 ± 2.22; NS: 25.1 ± 1.73; p = 0.0241) at the DDFT insertion in the distal phalanx. We concluded that the flexor tendons of the forelimb in equines with NS have different proportions of collagen than those that do not present the diagnosis, indicated by histologically visible increased proportions of non-aligned collagen and decreased of aligned collagen in the extracellular matrix.

The significance of surgically modifying soft tissue phenotype around fixed dental prostheses: An American Academy of Periodontology best evidence review.

BACKGROUND: This systematic review endeavored to investigate the effect of soft tissue phenotype modification therapy (PhMT-s) at sites with a tooth or an implant supported fixed dental prosthesis. METHODS: A comprehensive literature search was conducted by two independent examiners to identify relevant studies reporting differences in clinical, esthetic, or radiographic outcomes of interest between sites underwent PhMT-s and sites that remained untreated. Risk of bias assessment was calculated for all included studies. Meta-analyses involving endpoints of interest were performed when feasible. RESULTS: No controlled studies pertaining to tooth sites were identified. A total of six articles reporting on the outcomes of buccal soft tissue phenotype modification around implants were selected, of which, five were included in the meta-analyses. Quantitative analyses showed a weighted mean difference (WMD) of 0.98 mm (95% CI = 0.25 to 1.72 mm, P = 0.009) for change of tissue thickness; a WMD of -4.87% (95% CI = -34.27 to 24.53%, P = 0.75) for bleeding on probing (BOP); a WMD of 0.36 mm (95% CI = 0.12 to 0.59 mm, P = 0.003) for mucosal recession (MR); a WMD of 0.13 mm (95% CI = -0.11 to 0.36 mm, P = 0.30 for probing depth (PD); a WMD of 1.08 (95% CI = -0.39 to 2.55, P = 0.15) for pink esthetic score (PES), and a WMD of 0.40 mm (95% CI = -0.34 to 1.14 mm, P = 0.28) for marginal bone loss (MBL). CONCLUSIONS: Surgical modification of peri-implant soft tissue phenotype via PhMT-s may decrease the amount of MR. Future clinical trials are needed to warrant the clinical benefits of modifying soft tissue phenotype around tooth-supported restorations.

Factors Associated with Cognitive and Functional Performance in Indigenous Older Adults of Nariño, Colombia.

INTRODUCTION: Ethnicity in Latin America is a factor of poverty and social exclusion. Like in developed countries, demographic, medical, psychosocial, global cognitive, and functional variables interact in a complex relationship on the elderly population. Such interaction should be considered to determine cognitive and functional performance using screening tests. The aim of this study was to evaluate the demographic, medical, and psychosocial factors affecting global cognitive performance as well as functional activities. METHODS: The study was conducted in a Colombian elderly indigenous population which included a sample of 518 adults. This research employed a structural model of latent factors to assess the effects of demographic, medical, and psychosocial factors on cognitive and functional performance. The model was estimated by least squares and used a maximum-likelihood procedure, and it was determined RMSEA, TLI, and CFI to assess the model's goodness of fit. The categorical variables used in the model were as follows: (1) demographics, (2) psychosocial factors, (3) medical condition, (4) global cognition, and (5) functional factors. RESULTS: Demographics, in addition to medical and psychosocial factors, were related to global cognition and functional factors (RMSEA = 0.051, CI 90% 0.045-0.057, CFI = 0.901, and TLI = 0.881). CONCLUSION: These results provide strong evidence about the complex relationships among demographics, medical conditions, and psychosocial factors and their influence on global cognition and functional performance in Colombian indigenous elderly population.

Genotoxicity and Hemocompatibility of a Novel Calcium Aluminate-Based Cement.

OBJECTIVE: The aim of this in vitro study was to evaluate the genotoxicity and hemocompatibility of a novel calcium aluminate-based cement, EndoBinder (EB) (Binderware, São Carlos, SP, Brazil) and compare it with Angelus White Mineral Trioxide Aggregate (MTA) (AWMTA) (Angelus, Soluções Odontológicas, Londrina, PR, Brazil). METHODS: For evaluation of genotoxicity, a comet assay was performed with Chinese hamster ovary (CHO) cells that had been grown for 24 h in Dulbecco's Modified Eagle Medium incubated with each of the cements for 24 h at 37°C. DNA percentage in head and Olive tail moment were analyzed. For assessment of hemocompatibility, erythrocyte lysis quantification, and concentration of plasma fibrinogen were determined in human blood samples placed in contact with each of the materials. One way analysis of variance (ANOVA) followed by post hoc Tukey test and Student t-test were used for data analysis of genotoxicity and hemocompatibility, respectively. RESULTS: Results showed that the genotoxic effects of EB and AWMTA were comparable to that of the negative control, with no statistically significant differences between AWMTA and negative control (P>0.05). Compared to AWMTA, EB showed greater hemolytic potential when placed in direct contact with erythrocytes (P<0.05). Fibrinogen values were low for both materials, with protein concentration being greater in samples exposed to EB than to AWMTA. CONCLUSION: Both materials presented a higher hemolytic behaviour compared to what is established by international standards. Fibrinogen formation was low for both materials, and DNA damage induction was not observed in a comet assay.

Design, fabrication, and implantation of tube-shaped devices for the treatment of salivary duct diseases.

Introduction: Starch-based materials were designed using a special extrusion die in order to obtain a tube-shaped device for application to salivary duct treatment in the field of endoscopy, i.e., sialendoscopy . Methods: Extrusion process was used to produce starch tubes. Mechanical properties of the dry tube before implantation were determined using an axial compression test. A finite element study was carried out to simulate the behavior of the hydrated tube under external axial pressure. Hydrolysis of these devices in a simulated salivary solution was studied, as well as its glycerol kinetics release. An animal short-term implantation model for salivary ducts was proposed as a feasibility study for starch tube-shaped devices. Results: A continuous production of regular and size-controlled tubes was obtained. The very small diameter obtained, less than 2 mm, corresponds to the requirement of being insertable in a human salivary duct using sialendoscopy guidewire. Finite element analysis showed that the starch tube can still support an external pressure higher than 0.2 MPa without irreversible damage. After 4 days of implantation, the host response is encouraging and the inflammatory response for this type of procedure remains normal. Conclusion: These devices were adapted to sialendoscopic guidewires and able to be implanted in the salivary ducts of pigs. If a longer lasting tube is required, the crystallinity of the starch material should be improved.

Massive hemoptysis due to intercostal artery aneurysm in pulmonary tuberculosis.

Massive hemoptysis is a life-threatening complication of pulmonary tuberculosis. In the presence of pulmonary tuberculosis, massive hemoptysis can result from a number of different causes, with an artery aneurysm being rarely reported. Here we present a case of recurrent massive hemoptysis in a 28-year-old man suffering from active pulmonary tuberculosis due to an aneurysmatic lesion of the second intercostal artery. In patients presented with recurrent massive hemoptysis the non-bronchial systemic arterial blood supply should be assessed.

Comparison of Direct and Indirect Techniques to Develop Customized Implant Impression Copings: A Pilot Study.

The aim of this pilot study was to compare a direct and an indirect technique for fabricating customized impression copings. The accuracy of these techniques to capture the tissue contours that have been developed using implant-supported fixed interim restorations (ISFIRs) in single implants for their esthetic value were evaluated. Five patients presenting with maxillary central incisor ISFIRs were enrolled in the study. Customized impression copings were fabricated using a direct and an indirect technique. Specimens of experimental (direct and indirect technique) and control groups (ISFIR) were compared in terms of linear measurements on their buccolingual (BL) and mesiodistal (MD) dimensions at three different levels: platform, middle, and gingival margin. Statistically significant differences were detected between the control group and the direct technique specimens on both the gingival margin and middle levels (P < .05). Between the direct and indirect techniques, statistically significant differences were found in their MD and BL dimensions at the gingival margin level (G-MD, G-BL) and the buccolingual dimension at the middle level (M-BL) (P < .05). The indirect technique used for the fabrication of customized implant impression copings seems to be more accurate in capturing the profile of the ISFIR at all three levels (platform, middle, and gingival margin). The direct technique is accurate only at the platform level.

Effect of crystallinity and plasticizer on mechanical properties and tissue integration of starch-based materials from two botanical origins.

The application of starch-based materials for biomedical purposes has attracted significant interest due to their biocompatibility. The physical properties and crystal structure of materials based on potato starch (PS) and amylomaize starch (AMS) were studied under physiological conditions. PS plasticized with 20% glycerol presented the best mechanical properties with an elastic modulus of 1.6MPa and a weak swelling, remaining stable for 30 days. The in vitro cell viability of 3T3 cells after contact with extracts from PS and AMS with 20% glycerol is 72% and 80%, respectively. PS presented good tissue integration and no significant inflammation or foreign body response after 30 days intra-muscular implantation in a rat model, contrary to AMS. It was shown that glycerol plasticization favors a fast B-type crystallization of PS materials, enhancing their mechanical strength and durability, and making them a good candidate for bioresorbable and biocompatible materials for implantable medical devices.