Sonochemical time standardization for bioactive materials used in periimplantar defects filling

The aim of this study was determinate the best sonochemical time in order to obtain better bone characteristics when a bioactive material (Biogran) is used in the filling periimplantar defects. In this study, 32 rats were submitted to surgical proceedings to create a periimplantar defect that was filled with Biogran receiving different sonochemical times: 15 (G1), 30 (G2), 45 (G3) or 90 min (G4). The biomaterial was characterized through X-ray diffraction and scanning electron microscopy (SEM). In vivo analysis was performed through micro CT, laser confocal microscopy, immunohistochemistry and evaluation of bone cytoarchitecture through hematoxylin and eosin (HE) staining. The data were submitted to statistical testing, considering a significance level of p < 0.05. Rx diffraction of pure bioglass showed that it is predominantly amorphous; otherwise, there are small peaks at 23° and 31°. SEM shows that the longer the sonochemical time, the less edges the biomaterial will present. Within the groups, G1 and G2 showed the best quantity and quality by micro CT (p > 0.05). The best bone turnover result was found in G1 and G2, otherwise the better results were related to neoformed bone area, bone mineral apposition rate and bone implant contact to G1 (p < 0.05). G1 had the best results in terms of bone cytoarchitectural evaluation and immunohistochemistry. It is possible to conclude that Biogran that received 15 min of sonochemical treatment (G1) presented periimplantar bone repair with the best extracellular matrix properties, including the best quality and quantity of vital bone.

Oral health in patients with Prader-Willi syndrome: current perspectives

Prader-Willi syndrome (PWS) is a rare complex multisystem disorder and presents several aspects related to dentistry. The purpose of this review is to present current perspectives about oral health in patients with PWS. Delay development, hyperphagia, foamy and highly viscous saliva raise the risk of caries and contribute to tooth wear. Cariogenic foods uncontrolled consumption allows to obesity and dental problems progress worsening systemic disorders. These factors can be controlled. The success in follow-ups with caries free and oral health controlled demonstrate the importance of multidisciplinary team intervention corroborated by support at home from birth to adulthood. Thereby, current perspective on the disease is that there is possibility of proper maintenance of oral health in PWS patients. Guided care interferes positively with the overall well-being and quality of life of the individual with PWS and their family. A multidisciplinary team with a focus on teaching patients and family members will help minimize eventual problems.

Immunohistochemistry evaluation of BMP-2 with β-tricalcium phosphate matrix, polylactic and polyglycolic acid gel, and calcium phosphate cement in rats

PURPOSE

The installation of implants has become a routine procedure in the clinic. However, it takes time and adequate bone thickness, and for that, tissue engineering has made efforts to develop substitutes for autografts, in view of certain disadvantages of this material. The decision to choose the most suitable graft material for each case is an important step in the success of bone reconstruction. This study was to verify, by means of immunohistochemical study, that the addition of bone morphogenetic protein had some influence on biomaterials commercially available, taking into account the formation of mineralized tissue, bone replacement, and the amount of degradation of biomaterials.

METHODS

The sample consisted of 72 rats that were divided into eight treatment groups, in which two defects of 5 mm were made in each animal calvaria. Euthanasia was performed at 5, 15, and 30 days postop.

RESULTS

A histologic and histometric analysis was performed to quantitate the area of mineralized tissue formed, the area of newly formed bone, and the area of degradation of the biomaterials. Data were analyzed with multiple comparisons of means by Tukey contrasts, and significant difference was assigned at the level of P < 0.05. The proteins used for immunohistochemical analysis accounted for the process of formation, mineralization, and bone resorption and was performed using ordinal qualitative analysis, where from assigning scores.

CONCLUSIONS

Bone morphogenetic protein 2 was shown to be effective as an inducer of bone formation process independent biomaterial used mainly for accelerating the resorption process of the framework.

Comparison between piezoelectric surgery and conventional saw in sagittal split osteotomies: a systematic review

A systematic review of the advantages and disadvantages of piezoelectric surgery in comparison with conventional saws for sagittal split osteotomy (SSO) was performed. Relevant studies published in the last 10 years were identified through a search of the PubMed/MEDLINE, Science Direct, and Embase databases and assessed against predetermined eligibility criteria. The initial search resulted in 1736 articles. After applying the inclusion and exclusion criteria, 12 articles remained. A total of 799 patients with an average age of 27.5 years underwent SSO performed using a saw or ultrasonic device. Results showed that it took longer to perform the osteotomies using an ultrasonic device than using a conventional saw. At ≥6 months of follow-up, neurosensory disturbance was seen in 4.7% of patients who underwent piezoelectric surgery versus 61.6% of patients who underwent surgery in which a conventional saw was used. It was found that the use of piezoelectric surgery in SSO leads to the best outcome regarding neurosensory disturbance when compared to conventional saws (P=0.04) at ≥6 months of follow-up. Further studies are required for the evaluation of the other clinical parameters assessed.

Use of autogenous bone and beta-tricalcium phosphate in maxillary sinus lifting: a prospective, randomized, volumetric computed tomography study

The correction of bone defects can be performed using autogenous or alloplastic materials, such as beta-tricalcium phosphate (β-TCP). This study compared the changes in bone volume (CBV) after maxillary sinus lifting using autogenous bone (n = 12), autogenous bone associated with β-TCP 1:1 (ChronOS; DePuy Synthes, Paoli, CA, USA) (n = 9), and β-TCP alone (n = 11) as grafting material, by means of cone beam computed tomography (CBCT). CBV was evaluated by comparing CBCT scans obtained in the immediate postoperative period (5-7 days) and at 6 months postoperative in each group using OsiriX software (OsiriX Foundation, Geneva, Switzerland). The results showed an average resorption of 45.7 ± 18.6% for the autogenous bone group, 43.8 ± 18.4% for the autogenous bone+β-TCP group, and 38.3 ± 16.6% for the β-TCP group. All bone substitute materials tested in this study presented satisfactory results for maxillary sinus lifting procedures regarding the maintenance of graft volume during the healing phase before the insertion of implants, as assessed by means of CBCT.