A 3D printed TCP/HA structure as a new osteoconductive scaffold for vertical bone augmentation.

INTRODUCTION: OsteoFlux(®) (OF) is a 3D printed porous block of layered strands of tricalcium phosphate (TCP) and hydroxyapatite. Its porosity and interconnectivity are defined, and it can be readily shaped to conform the bone bed's morphology. We investigated the performance of OF as a scaffold to promote the vertical growth of cortical bone in a sheep calvarial model. MATERIALS AND METHODS: Six titanium hemispheres were filled with OF, Bio-Oss (particulate bovine bone, BO), or Ceros (particulate TCP, CO) and placed onto the calvaria of 12 adult sheep (6 hemispheres/sheep). Histomorphometric analyses were performed after 8 and 16 weeks. RESULTS: OF led to substantial vertical bone growth by 8 weeks and outperformed BO and CO by a factor 2 yielding OF 22% ± 2.1; BO 11.5% ± 1.9; and CO 12.9% ± 2.1 total new bone. 3 mm away from the bony bed, OF led to a fourfold increase in new bone relative to BO and CO (n = 8, P < 0.002). At 16 weeks, OF, BO, and CO behaved similarly and showed marked new bone synthesis. A moderate degradation was observed at 16 weeks for all bone substitutes. CONCLUSION: When compared to existing bone substitutes, OF enhances vertical bone growth during the first 2 months after implantation in a sheep calvarial model. The controlled porous structure translated in a high osteoconductivity and resulted in a bone mass 3 mm above the bony bed that was four times greater than that obtained with standard substitutes. These results are promising but must be confirmed in clinical tests.

Survival rates of short (6 mm) micro-rough surface implants: a review of literature and meta-analysis.

OBJECTIVE: The aim of this review was to test the hypothesis that 6 mm micro-rough short Straumann(®) implants provide predictable survival rates and verify that most failures occurring are early failures. MATERIALS AND METHODS: A PubMed and hand search was performed to identify studies involving micro-rough 6-mm-short implants published between January 1987 and August 2011. Studies were included that (i) involve Straumann(®) 6 mm implants placed in the human jaws, (ii) provide data on the survival rate, (iii) mention the time of failure, and (iv) report a minimum follow-up period of 12 months following placement. A meta-analysis was performed on the extracted data. RESULTS: From a total of 842 publications that were screened, 12 methodologically sound articles qualified to be included for the statistical evaluation based on our inclusion criteria. A total of 690 Straumann(®) 6-mm-short implants were evaluated in the reviewed studies (Total: placed-690, failed-25; maxilla: placed-266, failed-14; mandible: placed-364, failed-5; follow-up period: 1-8 years). A meta-analysis was performed on the calculated early cumulative survival rates (CSR%). The pooled early CSR% calculated in this meta-analysis was 93.7%, whereas the overall survival rates in the maxilla and mandible were 94.7% and 98.6% respectively. Implant failures observed were predominantly early failures (76%). CONCLUSION: This meta-analysis provides robust evidence that micro-rough 6-mm-short dental implants are a predictable treatment option, providing favorable survival rates. The failures encountered with 6-mm-short implants were predominantly early and their survival in the mandible was slightly superior.

TiNOx coatings on roughened titanium and CoCr alloy accelerate early osseointegration of dental implants in minipigs.

INTRODUCTION: Titanium nitride oxide (TiNOx) coatings are known for their biocompatibility, hardness and high resistance to corrosion and wear. Further, they can be applied by plasma vapor deposition onto a wide variety of metallic, mineral, or organic substrates. In cell cultures, TiNOx coatings applied onto SLA (sandblasted, large grit, acid etched)-roughened titanium surfaces increased human primary osteoblast proliferation by 1.5 times in the first 2 weeks after seeding, while maintaining a high degree of cell differentiation. Therefore, the objectives of the present study were (i) to determine whether these findings would translate into the enhanced osseointegration of TiNOx-coated implants in vivo and (ii) to compare the osseointegration of Ti-SLA (titanium-SLA) and CoCr-SLA (cobalt-chromium-SLA) implants coated with TiNOx. METHODS: Forty-eight cylinders made of Ti-SLA, Ti-SLA-TiNOx (TiNOx-coated Ti-SLA) and CoCr-SLA-TiNOx (TiNOx-coated CoCr-SLA) were implanted into the lower jawbone of 8 minipigs. The bone-to-implant contact was determined after 1 week, 2 weeks, 1 month and 3 months. RESULTS: Osseointegration proceeded normally on all 3 surfaces, with equal activity after the first week of healing. After 2 weeks, bone-to-implant contact was 1.8 times higher on TiNOx coatings, either deposited on Ti or on CoCr. These differences fell off after 1 and 3 months of healing. CONCLUSIONS: When compared to standard SLA titanium, TiNOx coatings enhance implant osseointegration during the first month of healing. Furthermore, this stimulating effect is independent of the substrate, leading to similar results whether the coating is applied onto SLA-Ti or onto SLA-CoCr.

Efficacy and predictability of short dental implants (<8 mm): a critical appraisal of the recent literature.

PURPOSE: This review of literature was conducted to evaluate the predictability of treatment outcomes with short dental implants (SDI), ie, implants shorter than 8 mm. MATERIALS AND METHODS: The review included studies, published between January 1990 and July 2011, that (1) involved SDI (<8 mm) placed in human jaws, (2) had a minimum of 20 SDI in their analysis, (3) provided data on survival rates, and (4) reported a minimum observation period of at least 3 months after placement. RESULTS: Forty-one studies fulfilled the above criteria; only 17 of these studies reported outcomes with microrough surface SDI. Six different lengths (4, 5, 6, 6.5, 7 and 7.5 mm) of microrough surface SDI with varying diameters (3.5 to 6 mm) were identified in the studies. A total of 1,828 microrough surface SDI were inserted and 45 failures were reported. Observation periods ranged from 3 months to 9 years. The reported survival rates for SDI ranged from 92.2% to 100%. From a total of 1,123 SDI inserted in specified jaw locations, failures were observed more often in the maxilla (n=297, failed=13) than in the mandible (n=826, failed=19). The review did not identify any correlation between implant diameter and survival for the microrough SDI. CONCLUSIONS: Microrough surface short implants (6 to 7.5 mm) appear to provide favorable survival rates and, therefore, can be predictably employed for simplification of implant therapy in situations of reduced alveolar heights in the posterior jaw segments.

TiNOx coatings increase human primary osteoblasts proliferation independently of the substrate: a short report.

INTRODUCTION: When applied onto SLA titanium, Titanium Nitride Oxide (TiNOx) coatings are known for their stimulating effect on osteoblast proliferation while maintaining a high degree of differentiation. OBJECTIVE: To determine whether the stimulating effect of TiNOx coatings is or is not dependent of the metal substrate. METHODS: A TiNOx coating was deposited on roughened stainless steel (SS-SLA-TiNOx). The proliferation and differentiation of human primary osteoblasts were determined and compared to that observed on standard SLA titanium. To this end, cell proliferation and gene expression were monitored for a time course of 3 weeks, with or without additional stimulation by 100 nM 1.25(OH)2 vitamin D3. RESULTS: A 1.5 fold increase in the proliferation rate of cells grown on SS-SLA-TiNOx as compared to Ti-SLA surfaces was observed. A high level of differentiation was also noted. CONCLUSION: TiNOx coatings yield similar proliferation and differentiation rates when applied onto roughened Ti and SS. This might translate into a more effective osseointegration of endosseous implants made of stronger metals than Ti.

Diagnostic yield of sputum, induced sputum, and bronchoscopy after radiologic tuberculosis screening.

RATIONALE: To assess feasibility and yield of diagnostic procedures after active case finding for tuberculosis with radiologic screening at the three main entry points for asylum seekers to Switzerland. METHOD: Prospective multicenter study on the value of symptoms, spontaneous and induced sputum, and bronchoscopy for the confirmation of tuberculosis in radiologically selected cases. RESULTS: Among 101 asylum seekers examined, spontaneous sputum was collected "on the spot" in 83 and yielded 7 (54%) of 13 smear-positive and 13 (39%) of 33 culture-positive cases. Morning sputum, collected in 84, yielded 8 (62%) and 16 (49%), and the two spontaneous sputa combined 9 (69%) and 20 (61%), respectively. Two additional induced sputa, collected in 91 persons, yielded no additional smear-positive, but yielded seven culture-positive cases (yield, 82%). Bronchoscopy, performed in 87 of 92 sputum smear-negative cases, yielded four additional smear-positive and six culture-positive cases. Culture confirmation was independently and significantly predicted by obtaining a specimen using bronchoscopy (adjusted odds ratio, 11.0; 95% confidence interval, 1.9-62) and a prior decision to treat (adjusted odds ratio, 3.0; confidence interval, 1.1-8.1). CONCLUSION: Radiographic anomalies compatible with tuberculosis found during screening are a poor guide to initiation of treatment. Respiratory and systemic symptoms correlated weakly with culture confirmation of tuberculosis. All radiologically selected cases must be examined with on-the-spot and early-morning sputum, regardless of symptoms. If both specimens are smear negative, the yield is increased by bronchoscopy and, to a lesser extent, by two samples of induced sputum. The examination of any single specimen has a low yield of 36 to 63% and is insufficient to exclude active tuberculosis.

[Suspected tuberculosis at a refugee center: 79 referred cases in 2 years at St. Loup Hospital]. / Suspicion de tuberculose chez les requérants d'asile: 79 cas référés en deux ans à l'Hôpital de Saint-Loup.

The recent opening, close to the hospital of Saint-Loup, of an application centre for foreigners who ask for a status of refugee in Switzerland gave us the opportunity, over the last two years, to evaluate 79 patients with suspected tuberculosis. Of them 67% came from sub-Saharan Africa and 25% from Eastern Europe. A bacillary tuberculosis was found in 19 cases (24%), requiring immediate treatment and a respiratory isolation of a mean duration of 18 days. In addition, 11 cases (14%) had non-bacillary tuberculosis with negative sputum smear but positive culture. This new situation led us to implement a specific strategy of hospital hygiene.