Antonio Carlos Aloise

Classification of midpalatal suture opening after surgically assisted rapid maxillary expansion using computed tomography.

OBJECTIVE The aim of this study was to classify the opening of the midpalatal suture (MPS) after surgically assisted rapid maxillary expansion (SARME) with disjunction of the pterygomaxillary suture through computed tomography (CT) analysis. STUDY DESIGN Seventy adults with bilateral transverse deficiency of the maxilla underwent SARME with pterygomaxillary disjunction. Seventy tomographies were performed before the surgery and 70 were performed after the final activation. The Hass appliance was used in 29 patients and Hyrax in 41 patients. The MPS opening was classified into 2 types: type I, total MPS opening from the anterior nasal spine to the posterior nasal spine, and type II, total MPS opening from the anterior nasal spine to the transverse palatine suture, with partial or nonexistent opening posterior to transverse palatine suture. RESULTS Type I opening was observed in 22 patients (31.5%), and type II opening in 48 patients (68.5%). In 5 cases, the opening posterior to the transverse palatine suture was paramedian. CONCLUSION Computed tomography allows the evaluation and classification of midpalatal suture openings after SARME with pterygomaxillary disjunction in type I (total) and type II (partial) MPS openings.

Xenograft Enriched with Autologous Bone Marrow in Inlay Reconstructions: A Tomographic and Histomorphometric Study in Rabbit Calvaria

Objective. The aim of this study was to evaluate the bone healing after the usage of a scaffold enriched with bone marrow. Study Design. Ten rabbits were divided into 2 groups of 5 animals. Bilateral 12 mm diameter defects were created in the parietal bones. In control group Bio-Oss were inserted in both defects and, in experimental group, Bio-Oss enriched with autologous bone marrow were inserted in both defects. In these two groups, one of the calvarial defects was covered with Bio-Gide. The rabbits were sacrified 8 weeks after surgery and both CT and histomorphometric analysis were done. Results. The CT showed a lower remaining defect area in the experimental group covered with Bio-Gide when compared with control group, with and without Bio-Gide. The histomorphometrics showed no difference between groups regarding the non-vital mineralized tissue area. For vital mineralized tissue area, the experimental group covered with Bio-Gide obtained a higher percentage area when compared with control group, with and without Bio-Gide. For non-mineralized tissue area, the experimental group covered with Bio-Gide obtained a lower percentage area when compared with control group, with and without Bio-Gide. Conclusion. Both autologous bone marrow and membrane can contribute to the enhancement of bone healing.

Maxillary Sinus Augmentation Combining Bio-Oss with the Bone Marrow Aspirate Concentrate: A Histomorphometric Study in Humans.

Purpose. To investigate the regenerative results obtained with the association of bone marrow aspirate concentrate using the Bone Marrow Aspirate Concentrate (BMAC) method to a xenogeneic bone graft (Bio-Oss) in sinus floor elevation. Materials and Methods. Using a randomized controlled study design in eight consecutive patients (age of 55.4 ± 9.2 years), 16 sinus floor lift procedures were performed with Bio-Oss alone (control group, CG, n = 8) or combined with bone marrow aspirate concentrate obtained via the BMAC method (test group, TG, n = 8). Six months after the grafting procedures, bone biopsies were harvested during implant placement and were analyzed by histomorphometry. Results. Histomorphometric analysis revealed a significantly higher amount (p < 0.05) of vital mineralized tissue in TG when compared to the CG (55.15 ± 20.91% and 27.30 ± 5.55%, resp.). For nonvital mineralized tissue, TG presented a statistically higher level of Bio-Oss resorption (p < 0.05) when compared with the CG (6.32 ± 12.03% and 22.79 ± 9.60%, resp.). Both groups (TG and CG) showed no significantly different levels (p > 0.05) of nonmineralized tissue (38.53 ± 13.08% and 49.90 ± 7.64%, resp.). Conclusion. The use of bone marrow concentrate obtained by BMAC method increased bone formation in sinus lift procedures.

Adipose-derived stem cells (ADSC) in the viability of a random pattern dorsal skin flap in rats

PURPOSE To evaluate the viability of random pattern dorsal skin flaps in rats after injection of adipose-derived stem cells (ADSC). METHODS Thirty five adult male Wistar EPM rats (weight 250-300 g) were distributed, at random, in two groups. I- Control (flap elevation with injection of saline solution) with fifteen animals and II- Experimental (flap elevation with injection of ADSC ) with fifteen animal. The ADSC were isolated from others five adult male rats. A dorsal skin flap measuring 10x4 cm was raised and a plastic barrier was placed between the flap and its bed in both groups and the injection (cells or saline solution) were perfomed immediately after the surgery. The percentage of flap necrosis was measured on the seventh postoperative day. RESULTS The ADSC were able to replicate in our culture conditions. We also induced their adipogenic, osteogenic and chondrogenic differentiation to verify their mesenchymal stem cells potentiality in vitro. The results were statistically significant showing that the ADSC decreased the area of necrosis (p<0.05). CONCLUSIONS The cells demonstrated adipogenic, osteogenic and chondrogenic differentiation potential in vitro. The administration of adipose-derived stem cells was effective to increase the viability of the random random pattern dorsal skin flaps in rats.

Adipose-derived stem cells (ADSC) in the viability of random skin flap in rats

PURPOSE To evaluate the effects of the adipose-derived stem cells (ADSC) in the viability of random skin flap in rats. METHODS Thirty five adult male Wistar rats (weight 250-300 g) were used. ADSC were isolated from adult male rats (n=5). ADSC were separated, cultured and then analyzed. A dorsal skin flap measuring 10 x 4 cm was raised and a plastic barrier was placed between the flap and its bed. After the surgical procedure, the animals were randomized into two groups (n=15 each group), group control and group ADSC. In all groups the procedures were performed immediately after the surgery. The percentage of flap necrosis was measured on the seventh postoperative day. RESULTS The ADSC were able to replicate in our culture conditions. We also induced their adipogenic, osteogenic and chondrogenic differentiation, verifying their mesenchymal stem cells potentiality in vitro. The results were statistically significant showing that the ADSC decreased the area of necrosis (p<0.05). CONCLUSION The cells demonstrated adipogenic, osteogenic and chondrogenic differentiation potential in vitro. The administration of adipose-derived stem cells was effective to increase the viability of the random skin flaps in rats.

TGF-β1 on induced osteogenic differentiation of human dermal fibroblast

PURPOSE To evaluate the role of transforming growth factor beta 1 (TGF-β1) on the induced osteogenic differentiation of human dermal fibroblasts. METHODS We performed four groups with cultured dermal fibroblasts according to the culture medium: CONTROL (DMEM culture medium); TGF-β1 (DMEM culture medium with 10 ng/ml of TGF-β1); OSTEOG (DMEM culture medium with 0.5 µg/ml of ascorbic acid, 10 mmol/l of β-glycerophosphate and 10 nmol/L of dexamethasone); and OSTEOG/TGF-β1 (osteogenic medium with 10 ng/ml of TGF-β1). Alkaline phosphatase (ALP) activity and the amount of osteocalcin (OC) in the supernatant, as well as the capability to form calcium phosphate deposits, were analysed for 28 days RESULTS There were significant differences (p<0.05) between CONTROL and TGF-β1 groups in comparison with OSTEOG and OSTEOG/TGF-β1 groups in the ALP activity and OC amount. Although, both osteogenic groups had the same behavior with regard the expression curve during the experimental time, the OSTEOG/TGF-β1 group achieved significantly higher ALP and OC levels and showed no significant difference in the levels of mineralized deposits and in comparison with the levels found in the OSTEOG group. CONCLUSION The addition of transforming growth factor beta 1 to the osteogenic culture medium increased the activity of alkaline phosphatase and the amount of osteocalcin, but TGF-β1 did not alter the presence of mineralized calcium phosphate deposits.

Keratinocyte growth factor protected cultured human keratinocytes exposed to oxidative stress

PURPOSE To evaluate effects of oxidative stress and supplementation of keratinocyte growth factor (KGF) on cultivated human keratinocytes. METHODS Oxidative stress was produced through addition of hydrogen peroxide (H(2)O(2)) to the culture medium. Cultivated human keratinocytes were divided in 4 groups: Group control (G C), Group KGF (G KGF), Group H(2)O(2) (G H(2)O(2)), Group H(2)O(2) and KGF (G H(2)O(2)-KGF). Each experiment was accomplished with the same lineage cultivated keratinocytes, in triplicate. Cell viability was evaluated by trypan blue exclusion assay. RESULTS The results showed that the culture medium supplemented with KGF presented a small rate of cell viability when compared to cells only in culture medium (p<0,001). It demonstrated that only the growth factor does not have protector effects for cells in vitro. However, in front of the oxidative stress produced by addition of hydrogen peroxide to the medium, KGF showed a beneficial effect, protecting cells when compared to the group that suffered hydrogen peroxide action but had not been exposed to KGF (p<0,001). CONCLUSION KGF determined protection to the primary human keratinocytes exposed to oxidative stress.

Autologous Periosteum-Derived Micrografts and PLGA/HA Enhance the Bone Formation in Sinus Lift Augmentation

Sinus lift augmentation is a procedure required for the placement of a dental implant, whose success can be limited by the quantity or quality of available bone. To this purpose, the first aim of the current study was to evaluate the ability of autologous periosteum-derived micrografts and Poly(lactic-co-glycolic acid) (PLGA) supplemented with hydroxyl apatite (HA) to induce bone augmentation in the sinus lift procedure. Secondly, we compared the micrografts behavior with respect to biomaterial alone, including Bio-Oss® and PLGA/HA, commercially named Alos. Sinus lift procedure was performed on 24 patients who required dental implants and who, according to the study design and procedure performed, were divided into three groups: group A (Alos + periosteum-derived micrografts); group B (Alos alone); and group C (Bio-Oss® alone). Briefly, in group A, a small piece of periosteum was collected from each patient and mechanically disaggregated by Rigenera® protocol using the Rigeneracons medical device. This protocol allowed for the obtainment of autologous micrografts, which in turn were used to soak the Alos scaffold. At 6 months after the sinus lift procedure and before the installation of dental implants, histological and radiographic evaluations in all three groups were performed. In group A, where sinus lift augmentation was performed using periosteum-derived micrografts and Alos, the bone regeneration was much faster than in the control groups where it was performed with Alos or Bio-Oss® alone (groups B and C, respectively). In addition, the radiographic evaluation in the patients of group A showed a radio-opacity after 4 months, while after 6 months, the prosthetic rehabilitation was improved and was maintained after 2 years post-surgery. In summary, we report on the efficacy of periosteum-derived micrografts and Alos to augment sinus lift in patients requiring dental implants. This efficacy is supported by an increased percentage of vital mineralized tisssue in the group treated with both periosteum-derived micrografts and Alos, with respect to the control group of Alos or Bio-Oss® alone, as confirmed by histological analysis and radiographic evaluations at 6 months from treatment.

Can bone marrow aspirate concentrate change the mineralization pattern of the anterior maxilla treated with xenografts? A preliminary study

Objective: To evaluate bony reconstruction of the atrophic anterior maxilla using particulate grafts with or without autologous bone marrow aspirate concentrate (BMAC). Materials and Methods: Eight patients with atrophy of the anterior maxilla due to teeth loss were selected and split into groups according to the type of material used: Control Group (CG) (n = 4) - particulate xenograft only and Test Group (TG) (n = 4) - a combination of particulate xenograft and BMAC. Both groups received a collagen membrane to cover the xenograft. After 4 months, during implant placement, a sample of bone was removed from the graft area using a 2 mm diameter trephine bur. The specimens were fixed and preserved for histomorphometric evaluation, which included the following parameters: Mineralized tissue (MT) and non-MT (NMT). Cone beam computed tomography was performed at 3 time intervals to measure bone thickness: (1) Before grafting, (2) 4 months and (3) 8 months postgrafting, using localized bone gain (mm) as the outcome variable. Results: Tomographic analysis revealed bone gain in CG of 3.78 ± 1.35 mm and 4.34 ± 1.58 mm at 4 and 8 months, respectively. TG showed an increase of 3.79 ± 0.52 mm and 4.09 ± 1.33 mm after 4 and 8 months, respectively. Histomorphometric analysis revealed that, for CG, MT- and NMT-related values were 52.3% ± 16.78% and 47.70% ± 5.55%, respectively, whereas for TG, they were 65.04% ± 20.98% and 34.96 ± 10.38, respectively. Conclusion: Although radiographic bone gain appeared similar between the groups, the use of BMAC obtained via the BMAC® method revealed an increased mineralization trend in the anterior maxilla. It must be highlighted, however, that this is a preliminary study with a relatively small sample population and further studies with larger sample sizes are needed to verify these results.

Stability of surgically assisted rapid palatal expansion with and without retention analyzed by 3-dimensional imaging

INTRODUCTION Surgically assisted rapid palatal expansion (SARPE) is the procedure of choice for treatment of adults with transverse maxillary deficiency greater than 7 mm. There is no consensus about the dentoskeletal effect of an orthodontic retainer on the outcome of SARPE. Our objective was to assess the effectiveness of an orthodontic retainer on dentoskeletal stability. METHODS Ninety digitized dental casts of 30 adults undergoing SARPE were divided into 2 groups-no retention (n = 15) and retention (n = 15)-and assessed. The dental casts were obtained at 3 checkpoints: (1) 7 days on average before SARPE (preoperatively), (2) 4 months after expansion, and (3) 10 months after expansion was completed. The retention patients received a transpalatal arch just after expander removal, at checkpoint 2. The transpalatal arch was kept for 10 months after completion of the expansion (checkpoint 3 and end of the study). The dental casts were scanned with a Vivid 9i 3D laser scanner (Konica Minolta, Wayne, NJ). The distances measured were premolar and molar intercusp distances, premolar and molar intercervical distances, premolar and molar inter-WALA (Will Andrews and Lawrence Andrews) ridge distances, and palate height at the maxillary first molar. RESULTS The planned maxillary expansion was within the expected amount (P <0.05). Palatal height at the 4-month checkpoint decreased by 0.79 mm (4.38%) (P <0.001) and again at the 10-month checkpoint by 0.38 mm (0.98%) (P >0.05) but not significantly in both groups. The premolar intercusp distance had a relapse at checkpoint 3 of 1.84 mm (7.18%) (P <0.001) in the no-retention group. Both groups had average relapses of 0.95 mm in the premolar intercervical distances, of 0.88 mm in the premolar inter-WALA ridge distances, of 1.04 mm in the molar intercusp distances, of 0.74 mm in the molar intercervical distances, and of 0.84 mm in the molar inter-WALA ridge distances (P <0.05) at checkpoint 3. CONCLUSIONS The analysis of relapse in both groups suggests that the use of a transpalatal arch as a retaining device does not improve dento-osseous stability.