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1.
Int J Comput Dent ; 25(1): 83-98, 2022 Mar 24.
Article in English | MEDLINE | ID: mdl-35322655

ABSTRACT

AIM: The objective of the present case series was to evaluate the 4-year outcomes of implants placed in the esthetic area using static computer-assisted implant surgery (s-CAIS) and restored with a one-abutment one-time (OAOT) protocol using custom-made zirconia abutments and cemented provisional crowns manufactured prior to surgery. Materials and methods: Ten consecutive implants were placed in the esthetic area. Based on a digital implant and prosthodontic planning, surgical guides were ordered and used for the preparation of definitive custom-made zirconia abutments and polymethylmethacrylate provisional crowns. Implants were placed using the s-CAIS guide, and prosthetic components were placed immediately. Implant outcomes were evaluated at the time of surgery, after 4 months, and after 4 years. RESULTS: All implants were successfully placed with s-CAIS and restored with final abutments and provisional crowns. No major prosthetic adverse events were observed. After 4 years, the implant survival rate was 100%, minor peri-implant bleeding on probing was reported, and very stable peri-implant bone levels were observed. The pink esthetic score showed that the prosthetic components were well integrated, and the peri-implant soft tissue was stable. CONCLUSIONS: Within the limitations of the present case series, these results suggest that emerging digital workflows allow the manufacture of final custom-made abutments and provisional crowns prior to surgery. This individualized OAOT procedure may reduce cement-related complications and improve esthetic outcomes by optimizing soft tissue healing with prosthetic components. However, such protocols have evolved toward fully digital workflows, and comparative clinical trials are needed.


Subject(s)
Dental Abutments , Esthetics, Dental , Crowns , Dental Materials , Follow-Up Studies , Humans
2.
Front Psychol ; 13: 1056834, 2022.
Article in English | MEDLINE | ID: mdl-36619105

ABSTRACT

Background: By using a practice like mindfulness, people may become more adaptable and flexible in difficult situations, which lowers the levels of unfavorable experiences. Only a small number of research have examined the connection between mindfulness and resilience, with mindfulness as a source of PWB influencing millennials' resilience when faced with adversity. This study sought to close this gap by exploring the role that mindfulness practice plays in millennials' PWB and subsequent increases in resilience to adversity. Methods: In this study, key components linked to mindfulness, PWB, and resilience are combined with a thorough literature assessment. Millennials who are active members of the Ti-Ratana Youth in Malaysia and the Buddhist Missionary Society of Malaysia (BMSM) Youth Section make up the study's sample population. Before completing the online survey form, each participant was instructed to engage in 4 weeks of supervised mindfulness practice. To assure the validity of the data gathered, it was crucial to secure the youth's commitment. Only 231 of the 300 respondents who received the link to the online survey had replies that could be used for further research. To analyze the collected data and conduct hypothesis testing, Smart-PLS was used. Results: Academic research has shown that factors, such as a heavy workload, time constraints, lengthy workdays, work-related home conflicts, and an unstable and uncertain environment all lead to a drop in PWB. According to the findings, the two most significant variables promoting resilience are mindfulness and positive PWB. The outcomes of this experimental study confirmed earlier findings that millennials' PWB and resilience are enhanced by mindfulness training. Conclusion: The study's findings suggest that, in times of high uncertainty, mindfulness-based intervention programs should be expanded to include all young people. This study offers empirical support for the effectiveness of mindfulness-based interventions in raising PWB and resilience.

3.
Front Microbiol ; 12: 533121, 2021.
Article in English | MEDLINE | ID: mdl-35046907

ABSTRACT

From the aboveground vegetation to the belowground microbes, terrestrial communities differ between the highly divergent alpine (above treeline) and subalpine (below treeline) ecosystems. Yet, much less is known about the partitioning of microbial communities between alpine and subalpine lakes. Our goal was to determine whether the composition of bacterioplankton communities of high-elevation mountain lakes differed across treeline, identify key players in driving the community composition, and identify potential environmental factors that may be driving differences. To do so, we compared bacterial community composition (using 16S rDNA sequencing) of alpine and subalpine lakes in the Southern Rocky Mountain ecoregion at two time points: once in the early summer and once in the late summer. In the early summer (July), shortly after peak runoff, bacterial communities of alpine lakes were distinct from subalpine lakes. Interestingly, by the end of the summer (approximately 5 weeks after the first visit in August), bacterial communities of alpine and subalpine lakes were no longer distinct. Several bacterial amplicon sequence variants (ASVs) were also identified as key players by significantly contributing to the community dissimilarity. The community divergence across treeline found in the early summer was correlated with several environmental factors, including dissolved organic carbon (DOC), pH, chlorophyll-a (chl-a), and total dissolved nitrogen (TDN). In this paper, we offer several potential scenarios driven by both biotic and abiotic factors that could lead to the observed patterns. While the mechanisms for these patterns are yet to be determined, the community dissimilarity in the early summer correlates with the timing of increased hydrologic connections with the terrestrial environment. Springtime snowmelt brings the flushing of mountain watersheds that connects terrestrial and aquatic ecosystems. This connectivity declines precipitously throughout the summer after snowmelt is complete. Regional climate change is predicted to bring alterations to precipitation and snowpack, which can modify the flushing of solutes, nutrients, and terrestrial microbes into lakes. Future preservation of the unique alpine lake ecosystem is dependent on a better understanding of ecosystem partitioning across treeline and careful consideration of terrestrial-aquatic connections in mountain watersheds.

4.
Ecology ; 101(10): e03132, 2020 10.
Article in English | MEDLINE | ID: mdl-32628277

ABSTRACT

Climate change is altering biogeochemical, metabolic, and ecological functions in lakes across the globe. Historically, mountain lakes in temperate regions have been unproductive because of brief ice-free seasons, a snowmelt-driven hydrograph, cold temperatures, and steep topography with low vegetation and soil cover. We tested the relative importance of winter and summer weather, watershed characteristics, and water chemistry as drivers of phytoplankton dynamics. Using boosted regression tree models for 28 mountain lakes in Colorado, we examined regional, intraseasonal, and interannual drivers of variability in chlorophyll a as a proxy for lake phytoplankton. Phytoplankton biomass was inversely related to the maximum snow water equivalent (SWE) of the previous winter, as others have found. However, even in years with average SWE, summer precipitation extremes and warming enhanced phytoplankton biomass. Peak seasonal phytoplankton biomass coincided with the warmest water temperatures and lowest nitrogen-to-phosphorus ratios. Although links between snowpack, lake temperature, nutrients, and organic-matter dynamics are increasingly recognized as critical drivers of change in high-elevation lakes, our results highlight the additional influence of summer conditions on lake productivity in response to ongoing changes in climate. Continued changes in the timing, type, and magnitude of precipitation in combination with other global-change drivers (e.g., nutrient deposition) will affect production in mountain lakes, potentially shifting these historically oligotrophic lakes toward new ecosystem states. Ultimately, a deeper understanding of these drivers and pattern at multiple scales will allow us to anticipate ecological consequences of global change better.


Subject(s)
Lakes , Phytoplankton , Chlorophyll A , Colorado , Ecosystem , Seasons
5.
Front Microbiol ; 10: 65, 2019.
Article in English | MEDLINE | ID: mdl-30778338

ABSTRACT

Although cryoconite holes, sediment-filled melt holes on glacier surfaces, appear small and homogenous, their microbial inhabitants may be spatially partitioned. This partitioning could be particularly important for maintaining biodiversity in holes that remain isolated for many years, such as in Antarctica. We hypothesized that cryoconite holes with greater species richness and biomass should exhibit greater partitioning between the sediments and water, promoting greater biodiversity through spatial niche partitioning. We tested this hypothesis by sampling frozen cryoconite holes along a gradient of biomass and biodiversity in the Taylor Valley, Antarctica, where ice-lidded cryoconite holes are a ubiquitous feature of glaciers. We extracted DNA and chlorophyll a from the sediments and water of these samples to describe biodiversity and quantify proxies for biomass. Contrary to our expectation, we found that cryoconite holes with greater richness and biomass showed less partitioning of phylotypes by the sediments versus the water, perhaps indicating that the probability of sediment microbes being mixed into the water is higher from richer sediments. Another explanation may be that organisms from the water were compressed by freezing down to the sediment layer, leaving primarily relic DNA of dead cells to be detected higher in the frozen water. Further evidence of this explanation is that the dominant sequences unique to water closely matched organisms that do not live in cryoconite holes or the Dry Valleys (e.g., vertebrates); so this cryptic biodiversity could represent unknown microbial animals or DNA from atmospheric deposition of dead biomass in the otherwise low-biomass water. Although we cannot rule out spatial niche partitioning occurring at finer scales or in melted cryoconite holes, we found no evidence of partitioning between the sediments and water in frozen holes. Future work should include more sampling of cryoconite holes at a finer spatial scale, and characterizing the communities of the sediments and water when cryoconite holes are melted and active.

6.
Environ Toxicol Chem ; 34(12): 2791-5, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26084619

ABSTRACT

Pesticide choice based on toxicity to nontarget wildlife is reliant on available toxicity data. Despite a number of recent studies examining the effects of glyphosate on amphibians, very few have aimed to understand the toxicological effects of glyphosate in combination with surfactants as it is commonly applied in the field. Land managers interested in making pesticide choices based on minimizing impacts to nontarget wildlife are hindered by a lack of published toxicity data. Short-term acute toxicity trials were conducted for glyphosate in the form of isopropylamine salt (IPA) alone and mixed with 2 surfactants: Agri-dex and Competitor with western toad (Anaxyrus [Bufo] boreas) tadpoles. Glyphosate IPA mixed with Competitor was 6 times more toxic than glyphosate IPA mixed with Agri-dex, and both mixtures were more toxic than glyphosate IPA alone. The median lethal concentrations reported for 24-h and 48-h exposures were 8279 mg/L (24 h) and 6392 mg/L (48 h) for glyphosate IPA alone; 5092 mg/L (24 h) and 4254 mg/L (48 h) for glyphosate IPA mixed with Agri-dex; and 853 mg/L (24 h) and 711 mg/L (48 h) for glyphosate IPA mixed with Competitor. The present study indicates that the toxicity of a tank mix may be greatly increased by the addition of surfactants and may vary widely depending on the specific surfactant.


Subject(s)
Bufonidae/growth & development , Environmental Pollutants/toxicity , Glycine/analogs & derivatives , Herbicides/toxicity , Surface-Active Agents/toxicity , Animals , Drug Synergism , Glycine/toxicity , Larva/drug effects , Toxicity Tests, Acute
7.
J Clin Periodontol ; 39(9): 887-94, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22708823

ABSTRACT

AIMS: Multiple surgical protocols using biomaterials have been proposed to limit the typical post-extraction bone resorption. However, because of the heterogeneity of the studies, particularly the differences in assessment methods, it is difficult to determine the superiority of one technique over another. The objective of this study was to describe a new radiographic method to draw a map of alveolar bone remodelling after alveolar ridge preservation procedures to compare different surgical techniques more accurately. The newly developed measuring method was applied to a case series describing a specific preservation technique. MATERIALS AND METHODS: Fourteen extraction sites (in 14 patients) located in the upper anterior maxilla were treated with bovine hydroxyapatite (0.25- to 1-mm particles) and a saddled connective tissue graft. A radiographic three-dimensional assessment of the hard tissues was performed at baseline and 3 months after the procedure. Standardized horizontal measurements were taken at three corono-apical levels (-2, -5 and -9 mm) and at three mesio-distal levels (mesial, centre and distal) in the buccal and palatal aspects. Vertical measurements were also recorded in nine regions superior to the alveolar crest. The measurements were performed by two independent observers and intra- and inter-observer effects were evaluated. RESULTS: No inter- and intra-observer effects were found when analysing the measurements from these two observers. The horizontal dimension of the crest decreased by 1.6 mm (20%) in the cervical regions (-2 mm level), decreased moderately, by 1 mm (12%), at the -5 mm level and decreased very little, 0.5 mm (6%), at the apical (-8 mm) level. The losses were always significantly higher in the buccal than in the palatal aspect. Buccally, the maximal bone remodelling at the cervical level remained below 1 mm. Vertical bone resorption was homogeneous and<1 mm in the nine measured regions. DISCUSSION: The radiographic measuring methodology proved to be reproducible. It can be applied in other clinical settings. It successfully assessed the alveolar ridge preservation technique (BHA+saddle connective tissue graft).


Subject(s)
Alveolar Bone Loss/pathology , Bone Substitutes/therapeutic use , Cephalometry/methods , Minerals/therapeutic use , Tooth Extraction/adverse effects , Adolescent , Adult , Alveolar Bone Loss/diagnostic imaging , Alveolar Bone Loss/prevention & control , Alveolar Process/anatomy & histology , Alveolar Process/diagnostic imaging , Alveolar Process/surgery , Alveolar Ridge Augmentation/methods , Animals , Cattle , Female , Humans , Imaging, Three-Dimensional , Male , Middle Aged , Osseointegration , Outcome Assessment, Health Care/methods , Radiography , Reproducibility of Results , Tooth Socket/anatomy & histology , Tooth Socket/diagnostic imaging , Tooth Socket/surgery
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