Follow-Up of an Implant-Supported Rehabilitation After Long-Term Use of Alendronate.

Considering the higher number of bisphosphonate prescriptions worldwide and the risk of medicine-related osteonecrosis of the jaws (MRONJs) associated with these drugs, this study aims to report a patient who had weekly used sodium alendronate for 7 years and was submitted to an implant-supported rehabilitation. The alendronate intake was interrupted by the physician 1 year prior to the beginning of the procedures until the whole dental treatment was finished. Moreover, the bone markers procollagen type 1 N-terminal propeptide and C-terminal cross-linking telopeptide of type 1 collagen were also evaluated and showed the following values, respectively: 150 pg/mg and 27.3 µg/L. The rehabilitation consisted of a careful extraction of teeth 34 and 48, external hexagon implants placement at 34, 36, 37, 46, and 47 sites and cone morse at 41 tooth region. During implants insertion, portions of the bone were collected. It was also performed, a gingival graft at 41 region. After 4 months, it was installed the provisional crowns and 1 year later, the definitive ones. It was observed success of the dental rehabilitation, without any clinical or radiographic signs of MRONJ. Moreover, mandibular bone showed normality aspects, with several osteocytes. Although, alendronate use was restarted after the rehabilitation had been finished, the 2-year follow-up has proved the success of the treatment. Based on these findings, it is possible to consider that the clinical protocol ensured the success of the dental rehabilitation, even with the long-term use of a bisphosphonate.

Esthetic solution to malpositioned implants with remodeling of soft tissue: a case report.

This article describes a clinical case of gingival conditioning with provisional fixed prostheses to improve the esthetics of the soft tissues adjacent to fixed prostheses placed on malpositioned implants. Gradual application of pressure to the tissues is an easy, nontraumatic technique for inducing formation of papillae and reestablishing the appropriate shape and contour of the gingival tissues, thereby improving esthetics and phonetics. The proposed treatment proved to be effective in remodeling the surrounding soft tissues, providing suitable contours, and restoring esthetics and function lost due to surgical treatment with malpositioned implants.

Graft incorporation and implant osseointegration following the use of autologous and fresh-frozen allogeneic block bone grafts for lateral ridge augmentation.

OBJECTIVES: To compare autogenous bone (AT) and fresh-frozen allogeneic bone (AL) in terms of histomorphometrical graft incorporation and implant osseointegration after grafting for lateral ridge augmentation in humans. MATERIALS AND METHODS: Thirty-four patients were treated with either AL (20 patients) or AT (14 patients) onlay grafts. During implant installation surgery 6 months after grafting, cylindrical biopsies were harvested perpendicularly to the lateral aspect of the augmented alveolar ridge. Additionally, titanium mini-implants were installed in the grafted regions, also perpendicularly to the ridge; these were biopsied during second-stage surgery. Histological/histomorphometric analysis was performed using decalcified and non-decalcified sections. RESULTS: Histological analysis revealed areas of necrotic bone (NcB) occasionally in contact with or completely engulfed by newly formed vital bone (VB) in both AT and AL groups (55.9 ± 27.6 vs. 43.1 ± 20.3, respectively; P = 0.19). Statistically significant larger amounts of VB (27.6 ± 17.5 vs. 8.4 ± 4.9, respectively; P = 0.0002) and less soft connective tissue (ST) (16.4 ± 15.6 vs. 48.4 ± 18.1, respectively; P ≤ 0.0001) were seen for AT compared with AL. No significant differences were observed between the groups regarding both bone-to-implant contact (BIC) and the bone area between implant threads (BA) on the mini-implant biopsies. CONCLUSION: Allogeneic bone block grafts may be an option in cases where a limited amount of augmentation is needed, and the future implant can be expected confined within the inner aspect of the bone block. However, the clinical impact of the relatively poor graft incorporation on the long-term performance of oral implants placed in AL grafts remains obscure.

Impact of diabetes mellitus and metabolic control on bone healing around osseointegrated implants: removal torque and histomorphometric analysis in rats.

OBJECTIVES: To evaluate bone healing around dental implants with established osseointegration in experimental diabetes mellitus (DM) and insulin therapy by histomorphometric and removal torque analysis in a rat model. MATERIALS AND METHODS: A total of 80 male Wistar rats received a titanium implant in the tibiae proximal methaphysis. After a healing period of 60 days, the rats were divided into four groups of 20 animals each: a 2-month control group, sacrificed at time (group A), a diabetic group (group D), an insulin group (group I), and a 4-month control group (group C), subdivided half for removal torque and half for histomorphometric analysis. In the D and I groups the DM was induced by a single injection of 40 mg/kg body weight streptozotocin (STZ). Two days after DM induction, group I received subcutaneous doses of insulin twice a day, during 2 months. Groups C and D received only saline. Two months after induction of DM, the animals of groups D, C and I were sacrificed. The plasmatic levels of glucose (GPL) were monitored throughout the experiment. Evaluation of the percentages of bone-to-implant contact and bone area within the limits of the implant threads was done by histomorphometric and mechanical torque analysis. Data were analyzed by anova at significant level of 5%. RESULTS: The GPL were within normal range for groups A, C and I and higher for group D. The means and standard deviations (SD) for histomorphometric bone area showed significant difference between group D (69.34 ± 5.00%) and groups C (78.20 ± 4.88%) and I (79.63 ± 4.97%). Related to bone-to-implant contact there were no significant difference between the groups D (60.81 + 6.83%), C (63.37 + 5.88%) and I (66.97 + 4.13%). The means and SD for removal torque showed that group D (12.91 ± 2.51 Ncm) was statistically lower than group I (17.10 ± 3.06 Ncm) and C (16.95 ± 5.39 Ncm). CONCLUSIONS: Diabetes mellitus impaired the bone healing around dental implants with established osseointegration because the results presented a lower percentage of bone area in group D in relation to groups C and I resulting in a lowest torque values for implant removal. Moreover, insulin therapy prevents the occurrence of bone abnormalities found in diabetic animals and osseointegration was not compromised.

Effectiveness of Hyaluronic Acid Injection for Interdental Papillae Recovery in Esthetic Areas: A Randomized Clinical Trial.

The aim of this study was to evaluate the effectiveness of hyaluronic acid (HA) injections used to reduce defects in the gingival papillae in esthetic areas. This randomized study included six patients requiring black triangle treatment in 19 defective papillae. After local anesthesia, less than 0.2 mL of HA was injected 2 to 3 mm into the tip of the deficient papilla in the apical direction. Analysis of the target regions with standardized photographs and 3D intraoral scanning (CEREC 4.5 software with RST files, Dentsply Sirona) was performed at baseline (T0) and at 1 month (T1), 2 months (T2), 3 months (T3), and 4 months (T4) after the initial application of HA. At each time period, the photographic analysis showed no statistically significant differences in linear tissue gain after HA gel application. The 3D analysis showed improvements in the vertical papillae tissue recovery at T3 (0.41 ± 0.21 mm) and T4 (0.38 ± 0.21 mm) when compared to T1 (0.13 ± 0.08 mm; P < .0001). Regarding the reconstruction of the interdental papillae, the general dimensions of the tissue in the black triangle areas showed a significant increase in size percentage at T3 (58% ± 32.9%) compared to T1 (30.41% ± 23.4%; P = .0054). Thus, the application of injectable HA was effective for filling papillae in the esthetic area. Int J Periodontics Restorative Dent 2023;43:e73-e80. doi: 10.11607/prd.5814.

Evaluation of hydrophilic surface osseointegration in low-density bone: Preclinical study in rabbits.

The aim of this study was to evaluate the osseointegration of a hydrophilic surface (blasting + acid etching + immersion in isotonic solution) in comparison with that of a control surface (blasting + acid etching) using an experimental model of low-density bone. To perform the study, 24 rabbits were submitted to the installation of 4 implants in the iliac bone bilaterally: 2 implants with a control surface and 2 implants with a hydrophilic surface. The rabbits were euthanized at 2, 4, and 8 weeks after implant installation. After euthanasia, one implant from each surface was used to perform the removal torque analysis, and the other implant was used for the execution of non-decalcified histological sections and evaluation of the bone implant contact (% BIC) as well as the fraction of bone tissue area between the implant threads (% BBT). The implants with a hydrophilic surface presented higher %BIC (42.92 ± 2.85% vs. 29.49 ± 10.27%) and % BBT (34.32 ± 8.52% vs. 23.20 ± 6.75%) (p < 0.05) in the 2-week period. Furthermore, the hydrophilic surface presented higher removal torque in the 8-week period (76.13 ± 16.00 Ncm2 vs. 52.77 ± 13.49 Ncm2) (p<0.05). Implants with a hydrophilic surface exhibited acceleration in the process of osseointegration, culminating in greater secondary stability in low-density bone than in implants with a control surface.

Lack of influence of the Schneiderian membrane in forming new bone apical to implants simultaneously installed with sinus floor elevation: an experimental study in monkeys.

AIM: To describe the early healing processes around the implants installed after elevation of the sinus mucosa applying the lateral access technique without the use of grafting material. MATERIAL AND METHODS: Immediately after the elevation of the maxillary sinus Schneiderian membrane by the lateral approach in eight monkeys, implants were installed without the use of grafting material. The healing of the tissue around the implants was evaluated after 4, 10, 20 and 30 days. Ground sections were prepared and analyzed histologically. RESULTS: After 4 days of healing, the formation of coagulum and provisional matrix was documented within the elevated area. At 10-day interval, sprouts of woven bone were in continuity with the parent bone, and partly in contact with the implant surface at the base of the augmented area. While bone-to-implant contact increased after 20 and 30 days, the area underneath the Schneiderian membrane appeared reduced in volume and condensed toward the apex of the implants. The sinus mucosa was to some extent collapsed onto the implant surface and on the newly formed bone. CONCLUSIONS: The void initially occupied by the coagulum after sinus membrane elevation shrank substantially during the observation period. A lack of influence of the Schneiderian membrane in bone formation apical to implants was documented in the early phase of healing.

Bioglass associated with leukocyte-poor platelet-rich plasma in the rabbit maxillary sinus: histomorphometric, densitometric, and fractal analysis.

The objective of the present study was to evaluate the outcomes of autogenous bone graft (AB) and bioglass (BG) associated or not with leukocyte-poor platelet-rich plasma (LP-PRP) in the rabbit maxillary sinus (MS) by histomorphometric and radiographic analysis. Twenty rabbits divided into 2 groups (G1, G2) were submitted to sinus lift surgery. In G1, 10 MS were grafted with AB and 10 MS were grafted with BG. In G2, 10 MS were grafted with AB + LP-PRP and 10 MS were grafted with BG + LP-PRP. After 90 days, the animals were killed and specimens were obtained, x-rayed, and submitted to histomorphometric, radiographic bone density (RD) and fractal dimension analysis. Radiographic bone density mean values (SD), expressed as aluminum equivalent in mm, of AB, BG, AB + LP-PRP, and BG + LP-PRP groups were 1.79 (0.31), 2.04 (0.39), 1.61 (0.28), and 1.53 (0.30), respectively. Significant differences (P < 0.05) were observed between BG and AB, and BG + PRP and BG. Fractal dimension mean values were 1.48 (0.04), 1.35 (0.08), 1.44 (0.04), and 1.44 (0.06), respectively. Significant differences were observed between BG and AB, and AB + LP-PRP and BG. Mean values for the percentage of bone inside MS were 63.30 (8.60), 52.65 (10.41), 55.25 (7.01), and 51.07 (10.25), respectively. No differences were found. No correlations were observed among percentage of bone, RD and FD. Histological analysis showed that MS treated with AB presented mature and new bone formation. The other groups showed minor bone formation. Within the limitations of this study, the results indicated that at a 90-day time end point, AB yielded better results than AB + LP-PRP, BG, and BG + LP-PRP and should be considered the primary material for MS augmentation.

Evaluation of Implants with Different Macrostructures in Type I Bone-Pre-Clinical Study in Rabbits.

The objective of this study was to assess the primary stability and the osseointegration process in implants with different macrostructures (Cylindrical vs. Hybrid Conical) in rabbit tibiae. Twenty-four (24) rabbits were used, divided into 3 experimental periods (2, 4 and 8 weeks) with 8 animals each. Each animal bilaterally received 2 implants from each group in the tibial metaphysis: Cylindrical Implant (CI) and Hybrid Conical Implant (HCI). All implants were assessed for insertion torque. After the experimental periods, one of the implants in each group was submitted to the removal counter-torque test and descriptive histological analysis while the other implant was used for microtomographic and histometric analysis (%Bone-Implant Contact). HCI implants showed higher insertion torque (32.93 ± 10.61 Ncm vs. 27.99 ± 7.80 Ncm) and higher % of bone-implant contact in the 8-week period (79.08 ± 11.31% vs. 59.72 ± 11.29%) than CI implants. However, CI implants showed higher values of removal counter-torque than HCI implants in the 8-week period (91.05 ± 9.32 Ncm vs. 68.62 ± 13.70 Ncm). There were no differences between groups regarding microtomographic data. It can be concluded that HCI implants showed greater insertion torque and bone-implant contact in relation to CI implants in the period of 8 weeks when installed in cortical bone of rabbits.

Human non-decalcified histology of three dental implants 45 months under function-a case report.

BACKGROUND: Fracture of an implant is a quite rare event but represents an important opportunity to evaluate the peri-implant bone tissue response to implant overload in human beings. This study aimed to evaluate bone tissue around three fractured titanium implants retrieved from a human maxilla, by histomorphometric and birefringence analyses. CASE REPORT: For this, the implants and the surrounding bone were removed after having been united to a tooth in function for 45 months, by a 4-mm internal diameter trephine bur, following an undecalcified section was obtained. The results showed a rate of 77.3% of bone-to-implant contact (BIC) and 80.3% of bone area filling within the limits of the implant threads. Under circularly polarized light microscopy investigation, the amount of the transverse collagen fibers was of 48.11%, and the amount of the longitudinal collagen fibers was of 51.89%. CONCLUSION: Within the limitation of this study, the possible cause of the implant fracture could be the association of overload, inadequate implant diameter, and fragile internal hexagon connection.

Evaluation of hydrophilic surface osseointegration in low-density bone: Preclinical study in rabbits

Abstract The aim of this study was to evaluate the osseointegration of a hydrophilic surface (blasting + acid etching + immersion in isotonic solution) in comparison with that of a control surface (blasting + acid etching) using an experimental model of low-density bone. To perform the study, 24 rabbits were submitted to the installation of 4 implants in the iliac bone bilaterally: 2 implants with a control surface and 2 implants with a hydrophilic surface. The rabbits were euthanized at 2, 4, and 8 weeks after implant installation. After euthanasia, one implant from each surface was used to perform the removal torque analysis, and the other implant was used for the execution of non-decalcified histological sections and evaluation of the bone implant contact (% BIC) as well as the fraction of bone tissue area between the implant threads (% BBT). The implants with a hydrophilic surface presented higher %BIC (42.92 ± 2.85% vs. 29.49 ± 10.27%) and % BBT (34.32 ± 8.52% vs. 23.20 ± 6.75%) (p < 0.05) in the 2-week period. Furthermore, the hydrophilic surface presented higher removal torque in the 8-week period (76.13 ± 16.00 Ncm2 vs. 52.77 ± 13.49 Ncm2) (p<0.05). Implants with a hydrophilic surface exhibited acceleration in the process of osseointegration, culminating in greater secondary stability in low-density bone than in implants with a control surface.

Resumo O objetivo deste estudo foi avaliar a osseointegração de uma superfície hidrofílica (jateamento + ataque ácido + imersão em solução isotônica) em comparação com uma superfície controle (jateamento + ataque ácido) usando um modelo experimental de osso de baixa densidade. Para realizar o estudo, 24 coelhos foram submetidos a instalação de 4 implantes bilateralmente no osso ilíaco: 2 implantes com superfície controle e 2 implantes com superfície hidrofílica. Os coelhos foram eutanasiados com 2, 4 e 8 semanas após a instalação dos implantes. Após a eutanásia, um implante de cada superfície foi usado para avaliar o torque de remoção, e o outro implante foi utilizado para execução de cortes histológicos não descalcificados e avaliação de contato osso implante (% BIC) bem como a fração da área tecido ósseo entre as roscas do implante (% BBT). Os implantes com superfície hidrofílica apresentaram maior %BIC (42.92 ± 2.85% vs. 29.49 ± 10.27%) e % BBT (34.32 ± 8.52% vs. 23.20 ± 6.75%) (p < 0.05) no período de 2 semanas. Além disso, a superfície hidrofílica apresentou maior torque de remoção no período de 8 semana (76.13 ± 16.00 Ncm2 vs. 52.77 ± 13.49 Ncm2) (p<0.05). Implantes com a superfície hidrofílica apresentaram aceleração no processo de osseointregração, culminando em melhor estabilidade secundária no osso de baixa densidade em relação a implantes com superfície controle.

Effect of the long-term administration of Cyclosporine A on bone healing around osseointegrated titanium implants: A histomorphometric study in the rabbit tibia.

The aim of this study was to investigate the effect of cyclosporine A (CsA) therapy on bone healing around osseointegrated implants in the rabbit by means of descriptive histologic and histomorphometric analyses. Eighteen rabbits received one implant each in the right tibia proximal metaphysis. After the bone-healing period of 3 months, 6 randomly selected animals were sacrificed (Group CTL-12) before the immunosuppression therapy initiation to obtain a standard of implant integration. Another six randomly selected animals were submitted to a daily subcutaneous (sc) injection of 10 mg/kg CsA (Group CsA) whereas the six remaining animals received daily sc injections of saline solution (Group CTL-24). Groups CTL-24 and CsA were sacrificed after another 12 weeks. Bone-to-implant contact (BIC), and bone area fraction occupancy (BAFO) within the implant threads were measured. Bone density (BD) and descriptive histological analyses were also accomplished. Rabbits under CsA therapy presented statistically lower percentage of BIC (33.28 ± 6.19) compared to the animals of CLT-24 (55.6 ± 17.73). No differences were found between CsA and CTL-12 (38.7 ± 7.87). Significant decreased percentage of BAFO between the implant threads in the CsA (48.43 ± 9.48) group compared to the CTL-24 (72.26 ± 11.72) was observed. No differences were found between CsA and CTL-12 (61.99 ± 13.94) groups. BD analysis showed significant lower BD in the CsA (48.56 ± 9.32) group compared to the CTL-12 (68.74 ± 10.89) and CTL-24 (77.96 ± 4.96) groups. Collectively, our findings demonstrated that CsA therapy negatively affect the bone healing around osseointegrated implants due to the significant lower values for BIC, BAFO, and BD.

Laser ablation in titanium implants followed by biomimetic hydroxyapatite coating: Histomorphometric study in rabbits.

Titanium surface texture and chemistry modification successfully improves the host response and consequently the bone-to-implant contact surrounding dental implants. The aim of the present study was to investigate, using histomorphometrical-analysis, the effects of titanium surface modification by laser-ablation (Nd:YAG) followed by thin chemical deposition of HA. Forty-eight rabbits received one implant by tibiae of AS-machined (MS), laser-modified (LMS), or biomimetic hydroxyapatite-coated (HA) surface. Bone-to-implant contact (BIC) and bone area (BBT) were evaluated after 4, 8, and 12 weeks, at cortical and cancellous regions. Average BIC in the cortical region was higher (P < 0.001) on the LMS and HA implants for all periods, with no differences between LMS and HA. For the cancellous area, the LMS and HA implants showed higher (P < 0.01) BIC than MS at the initial periods. The LMS and HA showed similar values in the cortical region, but a tendency of higher values for HA in the cancellous region was observed in all periods. For the BBT, the differences were found only between HA and MS after 4 weeks in the cortical region (P < 0.05), and after 12 weeks in the cancellous area (P < 0.05). Our results showed that HA biomimetic coating preceded by laser treatment induced the contact osteogenesis and allowed the formation of a more stable bone-implant interface, even in earlier periods.

The effect of laminin-1-doped nanoroughened implant surfaces: gene expression and morphological evaluation.

Aim. This study aimed to observe the morphological and molecular effect of laminin-1 doping to nanostructured implant surfaces in a rabbit model. Materials and Methods. Nanostructured implants were coated with laminin-1 (test; dilution, 100 µg/mL) and inserted into the rabbit tibiae. Noncoated implants were used as controls. After 2 weeks of healing, the implants were removed and subjected to morphological analysis using scanning electron microscopy (SEM) and gene expression analysis using the real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Results. SEM revealed bony tissue attachment for both control and test implants. Real-time RT-PCR analysis showed that the expression of osteoblast markers RUNX-2, osteocalcin, alkaline phosphatase, and collagen I was higher (1.62-fold, 1.53-fold, 1.97-fold, and 1.04-fold, resp.) for the implants modified by laminin-1 relative to the control. All osteoclast markers investigated in the study presented higher expression on the test implants than controls as follows: tartrate-resistant acid phosphatase (1.67-fold), calcitonin receptor (1.35-fold), and ATPase (1.25-fold). The test implants demonstrated higher expression of inflammatory markers interleukin-10 (1.53-fold) and tumour necrosis factor-α (1.61-fold) relative to controls. Conclusion. The protein-doped surface showed higher gene expression of typical genes involved in the osseointegration cascade than the control surface.

Evaluation of titanium implants with surface modification by laser beam. Biomechanical study in rabbit tibias.

The purpose of the present study was to evaluate, using a biomechanical test, the force needed to remove implants with surface modification by laser (Nd:YAG) in comparison with implants with machined surfaces. Twenty-four rabbits received one implant with each surface treatment in the tibia, machined surface (MS) and laser-modified surface (LMS). After 4, 8 and 12 weeks of healing, the removal torque was measured by a torque gauge. The surfaces studied were analyzed according to their topography, chemical composition and roughness. The average removal torque in each period was 23.28, 24.0 and 33.85 Ncm for MS, and 33.0, 39.87 and 54.57 Ncm for LMS, respectively. The difference between the surfaces in all periods of evaluation was statistically significant (p < 0.05). Surface characterization showed that a deep and regular topography was provided by the laser conditioning, with a great quantity of oxygen ions when compared to the MS. The surface micro-topography analysis showed a statistical difference (p < 0.01) between the roughness of the LMS (R(a) = 1.38 +/- 0.23 microm) when compared to that of the MS (R(a) = 0.33 +/- 0.06 microm). Based on these results, it was possible to conclude that the LMS implants' physical-chemical properties increased bone-implant interaction when compared to the MS implants.

Bone apposition and surface treatment in dental implants: histomorphometric pilot evaluation in rabbits

Introduction: The surface of dental implants is an important factor for osseointegration process and different methods of surface treatment have been described. Objective: To investigate the bone apposition in implant surface treated with sandblasting and acid-etching. Material and methods: Ten rabbits were selected and received one implant treated with method I in the left tibia and one implant treated with method II in the right tibia. Then, twenty implants were divided in two groups, according to methods of sandblasting and acid-etching (method I and method II). After 7, 14, 30, 45 and 60 days, tibias were retrieved and submitted to histotechnical procedures. The percentages of bone-implant contact (BIC) and bone area between threads (BABT) were determined throughout histomorphometric analysis and bone apposition was detected in implants of both groups. Results: In BABT measurements, an increase was observed after 45 and 60 days in the method II, compared to method I and no differences were found after 7, 14 and 30 days. In BIC measurements, an increase was detected with method II at 45 days when compared to method I. No differences between groups in BIC values were observed after 7, 14, 30 and 60 days. Conclusion: Our data demonstrated that implants treated with the method II presented increase in the contact between bone and implant after 45 days compared to method I. Moreover, with concern to bone area between threads, it was observed an increased in the method II after 45 and 60 days. However, both groups can be successfully used as a therapeutic strategy to rehabilitation of edentulous patients. Then, further experiments are needed to evaluate, in depth, the putative differential role of each surface treatment.

Aplicação de engenharia tecidual na elevação de seio maxilar: uma revisão sistemática da literatura / Tissue engineering application in sinus lifting procedures: a systematic literature review

O objetivo desta revisão de literatura é apresentar a aplicação da engenharia tecidual em cirurgias de elevação de assoalho do seio maxilar, relatando a influência dessas técnicas no aumento da altura e do volume ósseos no seio maxilar, e na osseointegração dos implantes instalados nas áreas enxertadas. A revisão foi realizada nas bases de dados PubMed e Scopus, utilizando-se as palavras-chave "scaffold" OR "tissue engineered" AND "sinus augmention" OR "sinus floor elevation". Na busca inicial, 463 artigos foram selecionados, dos quais 19 artigos para leituras dos abstracts, chegando ao final a nove artigos, que foram selecionados para avaliação da aplicação da engenharia tecidual em cirurgias de elevação do seio maxilar. Apesar dos resultados positivos da engenharia tecidual em procedimentos de elevação do seio maxilar relatados nos artigos selecionados, existe a necessidade de mais estudos, com melhor padronização de modelos experimentais e dos materiais utilizados, para que se chegue a conclusões convictas acerca do efeito da aplicação da engenharia tecidual na formação óssea em procedimentos de elevação de seio maxilar.

The purpose of this literature review is to present the state-of-the-art on the application of tissue engineering techniques in sinus lifts procedures, reporting the influence of these techniques in increasing bone height and volume in the maxillary sinus, and the osseointegration of the implants installed in the grafted areas. PubMed and Scopus databases were searched using the keywords "scaffold" OR "engineered tissue" AND "sinus augmention" OR "sinus floor elevation". In the initial search 463 articles were selected, of which 19 were selected abstracts reading, with nine papers selected by the end, for evaluation of the application of tissue engineering techniques in sinus lift procedures. Despite the positive results of tissue engineering procedures in sinus floor elevation reported in the selected articles, further studies are still needed, for a better standardization of experimental models and materials used, leading to definitive conclusions about the effects of the application of tissue engineering procedures on bone formation in maxillary sinus lifting procedures.

Evaluation of titanium implants with surface modification by laser beam: biomechanical study in rabbit tibias

The purpose of the present study was to evaluate, using a biomechanical test, the force needed to remove implants with surface modification by laser (Nd:YAG) in comparison with implants with machined surfaces. Twenty-four rabbits received one implant with each surface treatment in the tibia, machined surface (MS) and laser-modified surface (LMS). After 4, 8 and 12 weeks of healing, the removal torque was measured by a torque gauge. The surfaces studied were analyzed according to their topography, chemical composition and roughness. The average removal torque in each period was 23.28, 24.0 and 33.85 Ncm for MS, and 33.0, 39.87 and 54.57 Ncm for LMS, respectively. The difference between the surfaces in all periods of evaluation was statistically significant (p < 0.05). Surface characterization showed that a deep and regular topography was provided by the laser conditioning, with a great quantity of oxygen ions when compared to the MS. The surface micro-topography analysis showed a statistical difference (p < 0.01) between the roughness of the LMS (Ra = 1.38 ± 0.23 ìm) when compared to that of the MS (Ra = 0.33 ± 0.06 ìm). Based on these results, it was possible to conclude that the LMS implants' physical-chemical properties increased bone-implant interaction when compared to the MS implants.

Bio-Oss versus Bone Ceramic para elevação bilateral de seio maxilar no mesmo paciente: avaliação histológica qualitativa após seis meses / Bio-Oss versus Bone Ceramic in sinus floor elevation procedures in the same patient: qualitative histological evaluation after six months

O objetivo do presente caso clínico foi avaliar histologicamente o comportamento do Bio-Oss e do Bone Ceramic, utilizados separadamente, para elevação bilateral dos seios maxilares de um paciente com 49 anos, do sexo feminino, que procurou a Escola de Odontologia de Cuiabá/MT para reabilitação implantossuportada. Após bloqueios anestésicos adequados, foi realizada em cada hemimaxila a incisão tecidual com lâmina de bisturi de número 15. Para acesso ao rebordo maxilar atrófico, foi feito o descolamento do retalho total utilizando o descolador de Molt. Posteriormente, no rebordo maxilar atrófico, foi confeccionada uma janela lateral utilizando-se broca esférica diamantada. A parede anterior do seio foi ostectomizada, a membrana sinusal foi deslocada e elevada, sem qualquer perfuração. Subsequentemente, foram realizadas as inserções dos biomateriais: Bio-Oss (lado direito) e Bone Ceramic (lado esquerdo), por um único cirurgião-dentista. Após seis meses, foram obtidas biópsias bilaterais que foram processadas para inclusão em parafina. Cortes foram corados com hematoxilina e eosina para análise histológica qualitativa. Os achados histológicos deste caso clínico confirmam as propriedades osteocondutivas dos biomateriais investigados, visto que foram observados íntimos contatos entre o Bio-Oss ou o Bone Ceramic e o tecido ósseo neoformado. Porém, parece haver uma maior presença de tecido ósseo neoformado ao redor do Bio-Oss. Além disso, ao redor do Bone Ceramic, maior quantidade de células inflamatórias é observada. Apesar dos resultados indicarem ligeira superioridade do Bio-Oss, estudos envolvendo um maior número de pacientes devem ser realizados, a fim de confirmar os achados deste caso clínico.

The aim of this case report was to evaluate from the histologic aspect the behavior of Bio-Oss and Bone Ceramic for bilateral maxillary sinus elevation in a 49 years-old female patient. After adequate anesthesia, an incision was placed with a scalpel blade and the mucoperiosteal flap was elevated. Then, a lateral window was made with a round diamond bur. An osteotomy was placed in the anterior sinus wall, the sinus membrane was dislocated without perforation. After, Bio-Oss (right side) and Bone Ceramic (left side) were packed by the same surgeon. Six months later, biopsies were obtained and processed with H&E staining. The histological findings confirmed osteoconductive properties of both materials with close contact at the newly formed bone. However, more bone tissue seems to be available around Bio-Oss. Besides, more inflammation was seen around Bone Ceramic. Although the results indicate a slight superiority for Bio-Oss, more studies with a great sample size are necessary to corroborate the findings of this clinical report.

A influência do complexo B e do laser de baixa intensidade no processo de cicatrização de feridas odontológicas / The influence of B complex and low intensity laser in the healing process of dental wounds

Esforços têm sido concentrados na busca de um fármaco que tenha eficácia clínica no processo de cicatrização de feridas odontológicas. O complexo B pode ser importante no processo de cicatrização e reparação porque é constituído por nutrientes necessários às funções fisiológicas normais ou às reações metabólicas específicas. Além disso, a terapia com laser de baixa intensidade modula vários processos biológicos em modelos animais e em humanos, estimulando a síntese de colágeno, promovendo o processo de regeneração do músculo esquelético após injúria, diminuindo a resposta inflamatória, elevando a neoformação de vasos sanguíneos e auxiliando no processo de cicatrização. Desta maneira, é relevante o estudo da influência do complexo B e do laser de baixa intensidade na tentativa de melhorar o processo de cicatrização de feridas odontológicas, aumentando a eficácia clínica. Essa revisão bibliográfica sugere que tanto o laser de baixa intensidade como o complexo B podem aumentar o processo de cicatrização em feridas e procedimentos odontológicos.

Currently, efforts have been concentrated in the search for a drug clinically efficient on healing dental wounds. The B complex may be important in wound healing process since it is composed of nutrients necessary for normal physiological functions or for specific metabolic reactions. The low intensity laser therapy modulates various biological processes in both animals and humans stimulating collagen synthesis, promoting the regeneration process of skeletal muscle injury after injury In addition it reduces the inflammatory response, increasing the formation of new blood vessels and aiding the healing process. Therefore it is important to study the influence of B complex and of low intensity laser aiming to improve the healing process of dental wounds, increasing clinical efficacy. This literature review suggests that both B complex and low intensity laser therapy can improve the healing process of dental wounds and dental procedures.