Prevalence of anemia among elderly inpatients and its association with multidimensional loss of function

The purpose of this cross-sectional prospective study was to determine the prevalence of anemia among elderly hospitalized patients in Germany and to investigate its association with multidimensional loss of function (MLF). One hundred participants aged 70 years or older from two distinct wards (50 each from an emergency department and a medical ward, respectively) underwent a comprehensive geriatric assessment (CGA) consisting of the following six tools: Barthel Index, mini-mental state examination, clock-drawing test, timed up and go test, Esslinger transfer scale, and Daniels test. MLF as an aggregated outcome was diagnosed when three or more tests of the CGA showed an abnormal result. Anemia was defined according to WHO criteria as a hemoglobin (Hb) concentration of <13 g/dL for men and <12 g/dL for women. The prevalence of anemia was 60 %. Overall, 61 % of patients presented with three or more abnormal results in the six tests of the CGA and, thus, with MLF. Using logistic regression, we found a significant association of both anemia and low Hb concentrations with abnormal outcomes in five tests of the CGA and, therefore, with domain-specific deficits like mobility limitations, impaired cognition, and dysphagia. Furthermore, being anemic increased the odds of featuring MLF more than fourfold. This significant relationship persisted after adjustment for various major comorbidities. Both anemia and geriatric conditions are common in the hospitalized elderly. Given the association of anemia with MLF, Hb level might serve as a useful geriatric screening marker to identify frail older people at risk for adverse outcomes.     

One‐piece zirconia oral implants for single‐tooth replacement: Three‐year results from a long‐term prospective cohort study

Aim

This 3‐year report of a prospective long‐term cohort investigation aimed to evaluate the clinical and radiographic outcomes of a one‐piece zirconia oral implant for single‐tooth replacement.

Materials and Methods

Sixty‐five patients received a 1‐stage implant surgery with immediate temporization. Standardized radiographs were taken at implant insertion, after 1 year, and after 3 years to monitor peri‐implant bone levels. A univariate analysis of the association of different baseline parameters on marginal bone loss from implant insertion to 36 months was performed. Soft‐tissue parameters were evaluated at prosthesis insertion, after 6 months, after 1 year, and at the 3‐year follow‐up.

Results

After 3 years, six posterior site implants were lost, giving a cumulative survival rate of 90.8%. The mean marginal bone loss was 1.45 mm; 35% of the implants lost at least 2 mm bone, and 22% more than 3 mm. The univariate analysis did not identify any parameter associated with marginal bone loss. Probing depth, clinical attachment level, and bleeding index increased over 3 years, and plaque index decreased.

Conclusions

The low survival rate of the presented ceramic implant and especially the high frequency of advanced bone loss are noticeable but remain unexplained.     

Initial Bacterial Adhesion on Different Yttria-Stabilized Tetragonal Zirconia Implant Surfaces in Vitro

Bacterial adhesion to implant biomaterials constitutes a virulence factor leading to biofilm formation, infection and treatment failure. The aim of this study was to examine the initial bacterial adhesion on different implant materials in vitro. Four implant biomaterials were incubated with Enterococcus faecalis, Staphylococcus aureus and Candida albicans for 2 h: 3 mol % yttria-stabilized tetragonal zirconia polycrystal surface (B1a), B1a with zirconium oxide (ZrO₂) coating (B2a), B1a with zirconia-based composite coating (B1b) and B1a with zirconia-based composite and ZrO₂ coatings (B2b). Bovine enamel slabs (BES) served as control. The adherent microorganisms were quantified and visualized using scanning electron microscopy (SEM); DAPI and live/dead staining. The lowest bacterial count of E. faecalis was detected on BES and the highest on B1a. The fewest vital C. albicans strains (42.22%) were detected on B2a surfaces, while most E. faecalis and S. aureus strains (approximately 80%) were vital overall. Compared to BES; coated and uncoated zirconia substrata exhibited no anti-adhesive properties. Further improvement of the material surface characteristics is essential.     

Effect of different crown contours on periodontal health in dogs. Microbiological results

OBJECTIVES: In some clinical circumstances, i.e. in cases when the upper anterior region has to be restored by prosthetic means, it is necessary to place the margins of crowns and fixed partial dentures subgingivally. In addition, in periodontally compromised patients the restoration sometimes has to be overcontoured in order to replace the lost interdental papilla. The overcontoured crown margin may influence the subgingival bacterial composition. Therefore, the aim of the present investigation was to evaluate the effect of three different subgingival crown contours in dogs on the composition of the subgingival microbiota. METHODS: In four adult beagle dogs the second and third premolars were prepared in three quadrants and restored with single gold crowns. The unprepared second and third premolars in the last quadrant served as controls. The crowns had three different emergence profiles including a normal contour, a 30 degrees and a 50 degrees over-contour. During the entire study period, professional oral hygiene was performed seven times a week. Microbiological samples were harvested from four sites of test and control teeth (mesial, distal, buccal and lingual) at baseline, after 3 months, and after 5 months. RESULTS: The microbiological analysis (DNA-DNA hybridization technique) of the subgingival microbial flora revealed a dominance of P. intermedia, T. denticola and C. showae in all test and control groups at baseline. At three months, the total amount of bacteria increased and a broader variety of bacterial species could be detected. The detection frequency of most bacterial species increased from baseline to the 5-month evaluation. The frequency of detection of some species was higher in the 30 degrees and 50 degrees overcontoured test groups compared to the normal contour group and to the natural teeth. CONCLUSIONS: It can be concluded within the limits of this investigation that overcontoured gold crowns placed subgingivally have only slight effects on the microbiological composition in dogs when an intensive oral hygiene regimen was executed.     

Loaded custom-made zirconia and titanium implants show similar osseointegration: an animal experiment

BACKGROUND: Zirconia might be an alternative material to titanium for dental implant fabrication. The aim of the present study was to investigate the histological behavior (osseointegration) of loaded zirconia implants in an animal model and to compare it with the behavior of titanium implants. METHODS: Five months after extraction of the upper anterior teeth, 12 custom-made titanium implants (control group) and 12 custom-made zirconia implants (test group) were inserted in the extraction sites in six monkeys. Before insertion, the titanium implant surfaces were sandblasted with Al2O3 and subsequently acid-etched. The zirconia implants were only sandblasted. Six months following implant insertion, impressions were taken for the fabrication of single crowns. A further 3 months later, nonprecious metal crowns were inserted. Five months after insertion of the crowns, the implants with the surrounding hard and soft tissues were harvested, histologically prepared, and evaluated under the light microscope regarding the peri-implant soft tissue dimensions and mineralized bone-to-implant contact. RESULTS: No implant was lost during the investigational period. The mean height of the soft peri-implant tissue cuff was 5 mm around the titanium implants and 4.5 mm around the zirconia implants. No statistically significant differences were found in the extent of the different soft tissue compartments. The mean mineralized bone-to-implant contact after 9 months of healing and 5 months of loading amounted to 72.9% (SD: 14%) for the titanium implants and to 67.4% (SD: 17%) for the zirconia implants. There was no statistically significant difference between the different implant materials. CONCLUSION: Within the limits of this animal experiment, it can be concluded that the custom-made zirconia implants osseointegrated to the same extent as custom-made titanium control implants and show the same peri-implant soft tissue dimensions.     

In Vitro Time Efficiency,Fit, and Wear of Conventionally- versus Digitally-Fabricated Occlusal Splints

The purpose of the study was to compare conventional to digital workflows of occlusal splint production regarding time efficiency, overall fit, and wear. Fifteen Michigan splints were fabricated with a conventional and digital method. The duration for the dentist’s and the dental technician’s workload was recorded. Subsequently, the overall fit was examined with a four-level score (1–4). Paired t-tests were used to compare the time results for the conventional and digital workflows and the sign test to compare the overall fit. The mean time (16 min 58 s) for computerized optical impressions was longer than for conventional impressions (6 min 59 s; p = 0.0001). However, the dental technician needed significantly less mean time for the digital splint production (47 min 52 s) than for the conventional (163 min 32 s; p = 0.001). The overall fit of the digitally-fabricated splints was significantly better compared to the conventionally-fabricated splints (p = 0.002). There was no impact of the different materials used in the conventional and digital workflow on the wear (p = 0.26). The results suggest that the digital workflow for the production of occlusal splints is more time efficient and leads to a better fit than the conventional workflow.     

Behavior of CAL72 osteoblast-like cells cultured on zirconia ceramics with different surface topographies

OBJECTIVES: Because of its inherent strength, biocompatibility, and tooth-like color, zirconia ceramics have the potential to become an alternative to titanium as dental implant material. This study aimed at investigating the osteoblastic response to yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) with different surface topographies. METHODS: CAL72 osteoblast-like cells were cultured on machined (TZP-m), airborne particle abraded (TZP-s), and airborne particle abraded and acid-etched Y-TZP (TZP-sa) surfaces. Polystyrene and airborne particle abraded with large grit and acid-etched (SLA) titanium served as a reference control. The surface topography was examined by scanning electron microscopy (SEM) and profilometry. At culture days 3, 6, and 12, cell proliferation, at day 12 cell morphology, and cell-covered surface area were determined. RESULTS: The surface roughness of Y-TZP was increased by airborne particle abrasion and additionally by acid etching. No statistically significant differences were found between average roughness (R(a)) and maximum peak-to-valley height (R(p-v)) values of airborne particle abraded and acid-etched Y-TZP and SLA titanium. Whereas the cell proliferation assay revealed statistically significant greater values at day 3 for surface-treated Y-TZP and polystyrene cultures as compared with machined Y-TZP, no differences between the Y-TZP groups, SLA titanium, and polystyrene were observed at culture days 6 and 12. CONCLUSIONS: Cell morphology and cell-covered surface area were not affected by the type of substrate. The results suggest that roughened Y-TZP is an appropriate substrate for the proliferation and spreading of osteoblastic cells.     

The effect of a calcium hydroxide paste on wound healing and osseointegration of dental implants. A pilot study in beagle dogs.

The aim of this investigation was to evaluate the effect of a new calcium hydroxide suspension (Osteoinductal®) on the healing process of endosseous dental implants after placement. The material, composed of 25% calcium hydroxide, 25% Oleum pedum tauri and 50% vaselinum album, was developed with the intention to accelerate and to increase the mineralized bone to implant contact during the healing phase. Eight adult beagle dogs were used in this study. Prior to the beginning of the study the dogs had all mandibular premolars extracted. After the extraction sites had healed for 3 months. implant osteotomies were performed. On one side of the mandible Osteoinductal® was applied into the osteotomies before placement of the implants, whereas the other side did not receive Osteoinductal®. A total of 48 implants were placed with two losses during the entire study period. Two dogs were sacrificed 1 week, 2 weeks, 4 weeks and 3 months after implant placement. The specimens were evaluated histologically and histomorphometrically. In the histological evaluation an intense inflammatory reaction towards the calcium hydroxide suspension was found leading to a destruction of the bone surrounding the implants after 1 and 2 weeks. A giant cell reaction against the test material was visible at 4 weeks. At 3 months no inflammatory and no giant cell reaction could be depicted in the test group. The mean direct bone to implant contact or inflammatory tissue to implant contact showed no differences between test and control group for 1 and 2 weeks. Although statistically not significant, there was a clinical significant difference in the mineralized bone to implant contact between test and control group for the last two timepoints (i.e. 4-week specimens: test group 2.3±0.9%, control group 26% 11.1%; 3-month specimens: test group 10.5±12.7%, control group 60.7±13.7%). This study indicates that the use of the calcium hydroxide suspension Osteoinductal® has a detrimental effect on wound healing and osseointegration of dental imolants and cannot be 1 recommended for use with dental implants.