Effect of Autologous Growth Factors in Maxillary Sinus Augmentation: A Systematic Review

Purpose: The aim of the present study was to systematically evaluate the effect of autogenous platelet concentrates on the clinical and histomorphometric outcomes of maxillary sinus augmentation. Materials and Methods: MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched using a combination of specific search terms. Furthermore, a hand searching of the relevant journals and of the bibliographies of reviews was performed. Prospective comparative clinical studies were included. Implant survival and histomorphometric outcomes were evaluated. Results: Twelve studies were included. Four hundred forty‐five sinus floor augmentation procedures were considered. No difference in implant survival was reported between test and control groups. Six studies reported a beneficial effect of platelet concentrates based on histomorphometric outcomes, while another six studies found no significant effect. A large heterogeneity was found regarding study design, surgical techniques, graft materials, clinical and histomorphometric outcome variables, and methods for preparing platelet concentrates. Favorable effects on soft tissue healing and postoperative discomfort reduction were often reported but not quantified. Conclusions: A clear advantage of platelet concentrates could not be evidenced. Standardization in the experimental design is needed in order to detect the true effect of platelet concentrates in maxillary sinus augmentation procedure, especially regarding postoperative quality of life.     

Rasmussen encephalitis: Incidence and course under randomized therapy with tacrolimus or intravenous immunoglobulins

Purpose: Rasmussen encephalitis (RE) leads to progressive tissue and function loss of one brain hemisphere and often intractable epilepsy. This is the first randomized prospective treatment trial in RE. Methods: Germany‐wide, patients with suspected recent‐onset RE were recruited and if eligible randomized to tacrolimus or intravenous immunoglobulins (IVIGs). A loss of motor function or hemispheric volume by ≥15% (in patients >12 years at disease onset: ≥8%) led to study exit. Untreated patients served as a historical control group. Key Findings: Over 6.3 years, 21 patients with recent‐onset RE were identified. Sixteen were randomized to tacrolimus (n = 9) or IVIG (n = 7). Immunotreated patients had a longer “survival” than the historical controls. Neither treatment was more efficacious than the other. Two tacrolimus patients experienced serious adverse events. No immunotreated but several untreated patients developed intractable epilepsy. No patient with refractory epilepsy became treatment‐responsive under immunotherapy. Significance: The countrywide incidence rate of diagnosed RE is estimated as 2.4 cases/10⁷ people ≤ age 18/year. Treatment with tacrolimus or IVIG may slow down tissue and function loss and prevent development of intractable epilepsy. However, immunotherapy may “arrest” patients in a dilemma state of pharmacoresistant epilepsy but too good function to be offered functional hemispherectomy. These compounds may therefore contribute to the therapeutic armamentarium for RE patients without difficult‐to‐treat epilepsies.     

Effectiveness of C5 or C6-Cz assembly in predicting immediate post operative facial nerve deficit

Background

Intraoperative neurophysiology monitoring (IOM) is a valuable tool in cerebellopontine angle (CPA) surgeries posing risk to the cranial nerves. Transcranial electrical stimulation (TES) for cranial nerves has been performed in the last 7 years, for obtaining the facial nerve motor evoked potential (MEP), using either C3/C4-Cz or C3-C4 (or inverse) stimulating points, which have been correlated with facial nerve functional outcome.

Method

Intraoperative surgical and electrophysiological findings were documented prospectively. Patient files were reviewed for clinical data. We studied 23 patients undergoing CPA tumor resection using C5 or C6-Cz montage for TES, and were able to determine the correlation between facial nerve functional outcome and the amplitude drop of facial MEP above 50 %. Patients were evaluated for immediate facial nerve outcome and 6 months after the surgery. Follow-up was performed by structured telephone interviews with local physicians.

Results

The sensibility of the studied parameters was 92.8 % for amplitude drop of facial nerve MEP, with positive predictive value of 81.2 %. The absence of changes during IOM has shown a negative predictive value of 100 %.

Conclusion

In this series, the used montage was effective in predicting new facial deficit.     

When can it be not optimal to adopt a new technology? A viability theory solution to a two‐stage optimal control problem of new technology adoption

Politicians often deplore economic agents’ behaviour when they do not accept new technologies. For a new technology to be adopted, the new technology value function needs to dominate the old technology value function. If this is the case, a technology switch will occur. We characterise the value functions, without computing them, using the fact that their hypographs are viability kernels of some auxiliary control problems and study whether the graphs intersect. If they do not, the corresponding value functions do not dominate each other, and the switch cannot occur at a positive time. Using this characterisation, we analyse a technology adoption problem and show how to recognise the models, for which the switch will occur at time zero or never, without solving an optimal control problem. We conclude that the current control regime may not change if the economic agents’ preferences are modelled as an integral of discounted differences between a reward from the flow variable (control) and a penalty from the stock variable (state).Copyright © 2011 John Wiley & Sons, Ltd.     

Long-Term Bone Density Evaluation in Cerebrotendinous Xanthomatosis: Evidence of Improvement after Chenodeoxycholic Acid Treatment

Cerebrotendinous xanthomatosis (CTX) is known to be associated with osteoporosis and a higher incidence of bone fractures. However, the underlying pathogenesis is still unknown, and the effects of long-term replacement therapy with chenodeoxycholic acid (CDCA) on bone mineral density (BMD) have not been fully investigated. We studied 11 CTX patients aged 13–43 years. We performed dual-energy X-ray absorptiometry and assessed serum cholestanol and 25-hydroxyvitamin D (25-OHD) concentrations both at the time of diagnosis and after long-term treatment with CDCA. At baseline, we found low BMD in nine patients, cholestanol elevation in all subjects, and 25-OHD decrease in nine. After a mean follow-up time of 30 months (range 24–36), no substantial clinical changes including bone fractures occurred; and we detected a significant increase of both planar and volumetric BMD as well as normalization of plasma cholestanol levels and increase of serum 25-OHD. Densitometric improvement following CDCA introduction was not correlated to changes of biochemical parameters. Our study confirms the presence of low bone mass in CTX and demonstrates that long-term CDCA treatment increases bone mineral content. In this respect, improvement of vitamin D intestinal absorption secondary to bile acid restoration could play an important role. Moreover, our data strongly suggest the utility of periodic bone density evaluation in CTX patients.     

The use of optical fiber in endodontic photodynamic therapy. Is it really relevant?

This study analyzed the necessity of use of an optical fiber/diffusor when performing antimicrobial photodynamic therapy (PDT) associated with endodontic therapy. Fifty freshly extracted human single-rooted teeth were used. Conventional endodontic treatment was performed using a sequence of ProTaper (Dentsply Maillefer Instruments), the teeth were sterilized, and the canals were contaminated with Enterococcus faecalis 3 days’ biofilm. The samples were divided into five groups: group 1—ten roots irradiated with a laser tip (area of 0.04 cm²), group 2—ten roots irradiated with a smaller laser tip (area of 0.028 cm²), and group 3—ten teeth with the crown, irradiate with the laser tip with 0.04 cm² of area. The forth group (G4) followed the same methodology as group 3, but the irradiation was performed with smaller tip (area of 0.028 cm²) and G5 ten teeth with crown were irradiated using a 200-mm-diameter fiber/diffusor coupled to diode laser. Microbiological samples were taken after accessing the canal, after endodontic therapy, and after PDT. Groups 1 and 2 showed a reduction of two logs (99%), groups 3 and 4 of one log (85% and 97%, respectively), and group 5 of four logs (99.99%). Results suggest that the use of PDT added to endodontic treatment in roots canals infected with E. faecalis with the optical fiber/diffusor is better than when the laser light is used directed at the access of cavity.