Flapless transcrestal sinus augmentation using hydrodynamic piezoelectric internal sinus elevation with autologous concentrated growth factors alone.

PURPOSE: The purpose of this retrospective study was to evaluate the success rate of implants and the amount of sinus augmentation using the flapless hydrodynamic piezoelectric internal sinus elevation (HPISE) technique with autologous concentrated growth factors (CGF) alone. MATERIALS AND METHODS: A total of 11 maxillary sinuses were augmented using the HPISE technique through the flapless transcrestal approach. Sixteen implants (average 11.38 mm in length and 4.83 mm in diameter), with 2 different surfaces, were placed simultaneously with CGF alone. Plain panoramic radiograms and cone-beam computed tomograms (CBCT) were taken in all patients to evaluate the sinus augmentation preoperatively and postoperatively. RESULTS: The sinus membranes were successfully elevated, averaging 13.95 ± 6.61 mm in immediate postoperative CBCT without any iatrogenic perforation. After an average 23.8 weeks, the average bone gain above the sinus floor was 8.23 ± 2.88 mm in the axial aspect of CBCT. No complications were recorded in any patients during the follow-up period. CONCLUSION: The flapless transcrestal approach to the sinus augmentation using the HPISE technique with autologous CGF alone could be an alternative to the lateral approach, even at severely resorbed edentulous posterior maxilla with insufficient bone height.

Development of nanofiber coated indomethacin-eluting stent for tracheal regeneration.

In the case of tracheal rupture or stenosis, most effective way is to insert a commercially available metal stent. However, the implantation often causes a fever or a pain on the contact surface between trachea and the stent. And also the metal stent should be removed after a certain time implantation. Thus, we developed a functional tracheal drug eluting stent consisting of indomethacin, a nonsteroidal anti-inflammatory drug (NSAID), loaded nanofibers on a bare metal stent. To control the drug release kinetics and enhancement of mucosal regeneration, gelatin and PLCL were coated layer by layer on a metal stent by an electrospinning method. Indomethacin was loaded in the gelatin layer by soaking and drying method (0.1, 0.5, and 1 wt% in ethanol for 10 min). The morphology of functional drug eluting tracheal stent was characterized by scanning electron microscope (SEM). And mechanical properties of the constructs such as air leak pressure, ultimate tensile stress, and modulus were calculated and evaluated. Drug release was performed by a high performance liquid chromatography (HPLC). Stably coated gelatin and poly(L-lactide- co-epsilon-caprolactone) (PLCL) nanofibers were observed by SEM. Bi-layered nanofibers-coated stent showed enough mechanical properties as a tracheal stent, which confirmed by a custom-designed air leak mechanical test. For indomethacin loading on a stent, stent was immersed in a series of drug solutions (different concentrations) for 10 min. At the result of HPLC, total amounts of indomethacin on a stent were approximately 77, 323, and 670 ug/stent, respectively. Time dependent drug release kinetics of the tracheal stent showed a sustained release profile regardless of indomethacin content. Thus, functionally designed nanofiber coated tracheal stent with anti-inflammatory drug may be useful for tracheal regeneration.

Poly(L-lactic acid) nanocylinders as nanofibrous structures for macroporous gelatin scaffolds.

Electrospun Nanofiber sheets have been shown to mimic the structure of extracellular matrix (ECM). Although these nanofibers have shown great potential for use as tissue engineering scaffolds, it is difficult for the electrospun nanofiber based sheets to be shaped into the desired three-dimensional structure. In this study, poly(L-lactic acid) (PLLA), a biodegradable and biocompatible polyester, was electrospun to produce nanofibers that were treated with an amino group containing base in order to fabricate polymeric nanocylinders. The aspect ratio of the PLLA nanocylinders was tunable by varying the aminolysis time and density of the amino group containing base. The effects of changes in nanofibrous morphology of the PLLA nanocylinders/macro-porous gelatin scaffolds on cell adhesion and proliferation were evaluated. The results revealed different cell morphology, adhesion, and proliferation in the nanocylinders composite gelatin scaffold versus gelatin scaffold alone. Confocal laser scanning microscopy observation showed more spreading and a more flattened cell morphology after NIH3T3 cells were cultured on PLLA nanocylinders/gelatin scaffolds for 10 hours and 4 days. These results indicate that the gelatin/PLLA nanocylinder composite is a promising way to fabricate 3D nanofibrous scaffolds that accelerates cell adhesion and proliferation for tissue engineering.

Retrospective multicenter analysis of immediate provisionalization using one-piece narrow-diameter (3.0-mm) implants.

PURPOSE: The aim of this retrospective analysis was to report on the clinical outcome of immediate provisionalization using one-piece narrow-diameter implants. MATERIALS AND METHODS: The dental records of patients who received narrow implants were reviewed. Narrow-diameter (3.0-mm) one-piece implants were used to support restorations of missing maxillary lateral incisors and mandibular incisors. All implants were placed in a one-stage procedure according to the protocol recommended by the manufacturer, with immediate placement of provisional restorations. Following an average healing period of 3 months in the mandible and 5 months in the maxilla, the definitive prostheses were fabricated. The survival rate of the implants was analyzed, and radiographic evaluation was performed. RESULTS. Thirty-six patients (20 men and 16 women), aged from 42 to 72 years (average age of 53 years), were treated with 62 one-piece narrow implants. A success rate of 100% was observed over a period up to 33 months (mean, 23 ± 4.3 months). Among these, 8 implants were placed in maxillary lateral incisor positions and 54 implants were placed in mandibular incisor areas. Forty-four implants supported fixed partial prostheses, and 18 implants supported single crowns. The majority of the implants were 15 mm in length. Mean marginal bone loss at the 12-month follow-up visit was 0.53 ± 0.37 mm (range, 0 to 1.4 mm). CONCLUSIONS: The results obtained in this retrospective analysis suggest that the one-piece narrow-diameter implant can predictably restore missing maxillary lateral incisors and mandibular incisor with narrow interdental spaces and labiolingual widths.

Retrospective multicenter evaluation of tapered implant with a sandblasted and acid-etched surface at 1 to 4 years of function.

PURPOSE: The aim of this retrospective study was to evaluate the cumulative survival rate of tapered implant with a sandblasted and acid-etched surface placed in edentulous patients. MATERIALS AND METHODS: A retrospective study was performed by evaluating MIS seven implants consecutively placed from December 2004 to January 2008. Patient records were reviewed to determine gender, age at implant placement, implant location, prosthesis type, marginal bone loss according to treatment procedure, number of implants, and number of failed implants. The survival rate of the implants was analyzed, and radiographic evaluation was performed. RESULTS: A total of 294 implants were placed in 92 patients at the 3 centers. The observation period after implantation ranged from 22 to 59 months, with a mean of 38 months. The cumulative survival rate of MIS seven implants was 97.3%. After 1 year of functional loading, the mean marginal bone loss was 0.33 mm. CONCLUSION: This retrospective, multicenter study demonstrates that this dental implant system gives clinically reliable results.

Characteristics of patients with osteonecrosis of the jaw with oral versus intravenous bisphosphonate treatment.

PURPOSE: This retrospective study was aimed to evaluate the clinical characteristics and treatment outcomes in patients with osteonecrosis of the jaw who were receiving oral versus intravenous (IV) bisphosphonate (BP). MATERIALS AND METHODS: This retrospective study enrolled subjects who had been diagnosed with medication-related osteonecrosis of the jaw (MRONJ) during the period from July 2010 to June 2014. Information regarding the following demographic and clinical characteristics was collected: demographic data, administration route and type of BP, duration of BP medication, primary disease, number of involved sites, location of the lesion, number of surgeries, outcome of treatments, and laboratory test. All the patients were divided into oral and IV BP groups; and the between-group differences were compared. RESULTS: Total 278 patients were divided into two groups as per the route of BP administration. The proportion of oral BP-related MRONJ group were more dominant over IV BP group (oral BP, n = 251; IV BP, n = 27). In the IV BP group, the average dosing duration (31.4 months) was significantly shorter than that in the oral BP group (53.1 months) (P < 0.001). The average number of involved sites in the oral BP group (1.21 ± 0.48) was smaller than that in the IV BP group (1.63 ± 0.84) (P < 0.001). The average number of surgeries was higher in the IV BP group (1.65 ± 0.95) as compared to that in the oral BP group (0.98 ± 0.73) (P < 0.001). Outcome after the surgery for MRONJ after IV BP was poor than oral BP group. CONCLUSION: IV administration of BP causes greater inhibition of bone remodeling and could lead more severe inflammation. Therefore, even if the duration of IV administration of BP is shorter than that of oral BP, the extent of the lesion could be more extensive. Therefore, the result suggests that the MRONJ after IV BP for cancer patients needs to be considered as different characteristics to oral BP group for osteoporosis patents.

Efficacy of demineralized bone matrix paste for maxillary sinus augmentation: a histologic and clinical study in humans.

OBJECTIVES: The aim of this study is to report the effect of paste type of demineralized bone matrix (DBM) on augmentation of maxillary sinus using clinical parameters. STUDY DESIGN: Sinus augmentation with DBM was performed on 5 maxillary sinuses. This study included 5 patients, 4 men and 1 woman, aged from 41 to 67 years (mean age 55 years). After an average of 6 months' healing period, a core bone was obtained and stained for histologic analysis. RESULTS: All implants showed favorable osseointegration, and final restorations were completed without failure in all cases. Histologically, new bone formation was active around grafted bone and grafted bone was well integrated to the newly formed bone matrix. In histomorphometric analysis, vital bone volume was 25.2 +/- 11.9%. CONCLUSION: The DBM paste is clinically useful for the increase of bone volume in sinus augmentation, because of its favorable effect of new bone formation and easy handling.