A Double-Blind Randomized Controlled Trial (RCT) of Titanium-13Zirconium versus Titanium Grade IV Small-Diameter Bone Level Implants in Edentulous Mandibles - Results from a 1-Year Observation Period

Background: The use of endosseous dental implants has become common practice for the rehabilitation of edentulous patients, and a two‐implant overdenture has been recommended as the standard of care. The use of small‐diameter implants may extend treatment options and reduce the necessity for bone augmentation. However, the mechanical strength of titanium is limited, so titanium alloys with greater tensile and fatigue strength may be preferable. Purpose: This randomized, controlled, double‐blind, multicenter study investigated in a split‐mouth model whether small‐diameter implants made from Titanium‐13Zirconium alloy (TiZr, Roxolid?) perform at least as well as Titanium Grade IV implants. Methods and Materials: Patients with an edentulous mandible received one TiZr and one Ti Grade IV small‐diameter bone level implant (3.3 mm, SLActive®) in the interforaminal region. The site distribution was randomized and double‐blinded. Outcome measures included change in radiological peri‐implant bone level from surgery to 12 months post‐insertion (primary), implant survival, success, soft tissue conditions, and safety (secondary). Results: Of 91 treated patients, 87 were available for the 12‐month follow‐up. Peri‐implant bone level change (?0.3 ± 0.5 mm vs ?0.3 ± 0.6 mm), plaque, and sulcus bleeding indices were not significantly different between TiZr and Ti Grade IV implants. Implant survival rates were 98.9 percent and 97.8 percent, success rates were 96.6 percent and 94.4 percent, respectively. Nineteen minor and no serious adverse events were related to the study devices. Conclusion: This study confirms that TiZr small‐diameter bone level implants provide at least the same outcomes after 12 months as Ti Grade IV bone level implants. The improved mechanical properties of TiZr implants may extend implant therapy to more challenging clinical situations.     

Reversible skeletal disease and high fluoride serum levels in hematologic patients receiving voriconazole

We here investigate the occurrence of fluoride intake-associated alterations in patients with hematologic disease on triazol antifungal medication. Clinical, laboratory, and radiology data of overall 43 patients with hematologic malignancies taking voriconazole (n = 20), posaconazole (n = 8), and itraconazole (n = 4), and a hematologic patient control group (n = 11) are described. Bone pain and radiologic evidence of periostitis were exclusively observed in patients receiving long-term voriconazole. Cessation of treatment led to clinical improvement in all cases. In line with clinical evidence, fluoride serum concentration was elevated in patients receiving voriconazole (median, 156.5 μg/L; interquartile range, 96.8 μg/L; normal < 30 μg/L) but not in the other treatment groups (P < .001 for all comparisons vs voriconazole). We conclude that serum fluoride levels were elevated on average 5-fold above normal levels in hematologic patients receiving voriconazole. Clinically relevant skeletal disease was associated with renal insufficiency and above 10-fold elevated fluoride levels, and was reversible on termination of voriconazole treatment.     

Long‐Term Stability of Contour Augmentation With Early Implant Placement Following Single Tooth Extraction in the Esthetic Zone: A Prospective,Cross‐Sectional Study in 41 Patients With a 5‐ to 9‐Year Follow‐Up

Background: Early implant placement with simultaneous contour augmentation is documented with short‐ and medium‐term studies. The long‐term stability of contour augmentation is uncertain. Methods: In this prospective, cross‐sectional study, 41 patients with an implant‐borne single crown were examined twice, in 2006 and 2010. Clinical, radiologic, and esthetic parameters were assessed at both examinations. In addition, a cone beam computed tomographic (CBCT) image was obtained during the second examination to assess the dimensions of the facial bone wall. Results: All 41 implants demonstrated ankylotic stability without signs of peri‐implant infection at both examinations. The clinical parameters remained stable over time. Satisfactory esthetic outcomes were noted, as assessed by the pink and white esthetic score (PES/WES) indices. Overall, the PES scores were slightly higher than the WES scores. None of the implants developed mucosal recession over time, as confirmed by values of the distance between implant shoulder and mucosal margin and cast measurements. The periapical radiographs yielded stable peri‐implant bone levels, with a mean distance between implant shoulder and first visible bone‐implant contact value of 2.18 mm. The CBCT analysis demonstrated a mean thickness of the facial bone wall ≈2.2 mm. In two implants (4.9%) no facial bone wall was detectable radiographically. Conclusions: This prospective cross‐sectional study demonstrates stable peri‐implant hard and soft tissues for all 41 implants examined and satisfactory esthetic outcomes overall. The follow‐up of 5 to 9 years confirmed again that the risk for mucosal recession is low with early implant placement. In addition, contour augmentation with guided bone regeneration was able to establish and maintain a facial bone wall in 95% of patients.     

Healing of osteotomy sites applying either piezosurgery or two conventional saw blades: a pilot study in rabbits

Purpose

The purpose of this study was to compare bone healing of experimental osteotomies applying either piezosurgery or two different oscillating saw blades in a rabbit model.

Methods

The 16 rabbits were randomly assigned into four groups to comply with observation periods of one, two, three and five weeks. In all animals, four osteotomy lines were performed on the left and right nasal bone using a conventional saw blade, a novel saw blade and piezosurgery.

Results

All three osteotomy techniques revealed an advanced gap healing starting after one week. The most pronounced new bone formation took place between two and three weeks, whereby piezoelectric surgery revealed a tendency to faster bone formation and remodelling. Yet, there were no significant differences between the three modalities.

Conclusions

The use of a novel as well as the piezoelectric bone-cutting instrument revealed advanced bone healing with a favourable surgical performance compared to a traditional saw.     

Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC): Occupational Health and Safety Aspects

Background

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a novel approach for treating peritoneal carcinomatosis. First encouraging results have been obtained in human patients. However, delivering chemotherapy as an aerosol might result in an increased risk of exposure to health care workers, as compared with other administration routes.

Methods

PIPAC was applied in two human patients using chemotherapeutic drugs (doxorubicin and cisplatin), and air contamination levels were measured under real clinical conditions. Air was collected on a cellulose nitrate filter with a flow of 22.5 m³/h. To exclude any risk for health care workers, both procedures were remote controlled. Toxicological research of cisplatin was performed according to NIOSH 7300 protocol. Sampling and analysis were performed by an independent certification organization.

Results

The following safety measures were implemented: closed abdomen, laminar airflow, controlled aerosol waste, and protection curtain. No cisplatin was detected in the air (detection limit < 0.000009 mg/m³) at the working positions of the surgeon and the anesthesiologist under real PIPAC conditions.

Conclusions

For the drugs tested, PIPAC is in compliance with European Community working safety law and regulations. Workplace contamination remains below the tolerance margin. The safety measures and conditions as defined above are sufficient. Further protecting devices, such as particulate (air purifying) masks, are not necessary. PIPAC can be used safely in the clinical setting if the conditions specified above are met. However, a toxicological workplace analysis must be performed to confirm that the procedure as implemented complies with local regulations.     

Quantitative MRI and loss of free ambulation in Duchenne muscular dystrophy

The purpose of this ethics approved trial was to correlate quantitative MRI with functional abilities in both ambulant and non-ambulant Duchenne muscular dystrophy (DMD). Twenty patients with genetically confirmed DMD were recruited. Physical assessment was performed using the motor function measurement (MFM) scale. Axial 3T MRI scans of the thighs were acquired using T1-weighted in- and opposed-phase images (TR = 20 ms, TE₁ = 2.45 ms, TE₂ = 3.68 ms, flip angle = 15°) to calculate the relative fat fraction according to the two-point Dixon method in the knee extensors, flexors, and adductor muscles. The average MFM was 65.3 % and correlated negatively to age (r ² = 0.60). Overall mean fat fraction correlated positively to age (r ² = 0.51–0.64). An average of 5 % increase in mean fat fraction per year was calculated. Mean fat fraction of the quadriceps showed a high negative correlation (r ² = 0.93) to the D1 (standing position and transfers) component of the MFM. A cutoff for mean fat fraction of 50 % predicted loss of ambulation with a sensitivity of 100 % and a specificity of 91 %. Therefore, quantitative muscle MRI seems to be a promising endpoint for short clinical trials evaluating the effect of newer treatments on the time of loss of ambulation in DMD.