1,721,247 research outputs found
Histologic Observations of Two Dental Implants Retrieved After Osseointegration
No full textThis study aimed to histologically analyze the bony tissue formed around dental implants after osseointegration. A 58-year-old patient presented with pain and discomfort caused by two dental implants in her maxilla placed 8 months earlier. At clinical and radiographic analysis, the implants appeared well osseointegrated but tilted buccally, emerging in nonkeratinized mucosa. For this reason, the discomfort began right after the prosthetic load, 4 months after implant placement, and the patient felt pain when wearing the implant-supported removable prosthesis. Both implants were made of titanium, airborne-particle abraded with zirconium oxide, and etched with mineral acids. The implants were removed, preserving the bone around the implant threads, and replaced with two new implants, inserted in a prosthetically guided, correct position. The removed implants were histologically observed. Histologic analysis showed good bone-to-implant contact, mature bone with few marrow spaces, presence of direct connecting bridges between the peri-implant bone trabeculae and the implant surface, and no inflammatory cells nor connective fibrous tissue ingrowth. This study showed that dental implants coated with a rough surface were properly osseointegrated, with no inflammatory signs nor connective fibrous tissue ingrowth, 8 months after placement
Combination of allograft blocks and putty in the inlay technique: clinical and histological observations
No full textAim: In case of atrophic posterior mandibles, the inlay bone graft technique showed remarkable results in terms of vertical bone augmentation and the use of allografts seems to be able to accelerate graft integration and therefore implant rehabilitation. Material and Methods: This case reports clinical and histological evaluations of an the inlay augmentation procedure performed with two different forms of allograft. Two cancellous blocks were used at the sides of the grafted area in order to support the crononally-positioned bony segment, whereas putty was placed between the blocks. Three months later, a CT scan demonstrated good graft integration with sufficient bone vertical increase and density. At implants placement, bone core biopsies were taken and histologically processed. During implant placement,
the block was stable with good clinical osteointegration. Histological analysis showed presence of compact bone revealing
areas of demarcation between grafted bone, newly formed bone and bone regeneration areas. Results: The simultaneous use of both blocks and putty cancellous grafts increased clinical and histological outcomes. The presence of the blocks gave stability to the osteotomized bony
segment assuring an adequate bony vertical increase, whereas the putty increased and accelerated the graft integration. Moreover, the bony segment was clinically stable and no bone plates were used to fix it to the basal bone. Conclusion: In this case, after only 3 months from grafting, allografts showed to be effective materials for the reconstruction of the posterior mandible with inlay technique. According to
the preliminary results, this material represent a good clinical alternative to autologous and inorganic bovine bone
Histologic analysis of two dental implants extracted after osseointegration
No full textPurpose. The aim of this case report is to analyze and observe the bone tissue formation around two dental implants after their osseointegration. Methods and Materials. A 58 y.o. woman was referred to the Division of Periodontology and Implantology (University of Bologna, Italy) due to severe pain and discomfort caused by two of the four dental implants placed in the upper jaw (sites #13 and #23) in a private practice 8 months before. Implants were made of titanium, sandblasted with zirconium oxide and etched with mineral acids (Sweden&Martina, Due Carrare, Italy). At clinical and radiographic analysis, implants appeared properly osseointegrated but placed tilted way too buccaly, with their emergence profile in non-keratinized oral mucosa. For the above-mentioned reasons, the patient started having discomfort immediately after the prosthetic load occurred four months after implants placement. The patient was rehabilitated with an implant supported removable prosthesis. The patient explained difficulties to perform adequate oral hygiene and declared pain every time she was wearing the implant-supported removable prosthesis. The implants were removed, preserving the bone around implant threads, and replaced with two new dental implants, placed in a prosthetic-guided correct inclination. The removed implants were processed for histological analysis in accordance with Checchi V. & al, 2015.
Results. The histological analysis revealed proper osseointegration of the implant fixture after eight months (4x figures). Histological views of biopsies show good bone-implant contact recorded from the coronal side to the apical implant section (4x figures). Presence of direct connecting bridges between the peri-implant bone trabeculae and the implant surface were recorded (10x figures). Conclusions.
This case report clearly shows how after 8 months from implant placement, the fixtures coated with a rough surface were properly osseointegrated with good bone-implant contact recorded along their entire surface
Reconstruction of atrophied posterior mandibles with inlay technique and allograft block: histological case reports
No full textBackground: Implant placement may be challenging in areas with limited alveolar bone height, therefore augmentation procedures before implants placement become mandatory. Several treatment modalities have been developed for bone incrementation, and it has been reported that the number of complications and failures associated with the various techniques remain high for vertical bone augmentation. The inlay bone graft technique has been recently applied in the posterior mandible with remarkable results in terms of vertical bone augmentation. In the literature there are no strong evidences in relation to the use of allografts
in the inlay technique since they have been previously proposed only as onlay or veneers.
Aim/Hypothesis: In the present case series we describe the histological appearances and histomorphometric evaluation of the regenerated areas of five patients, after two/three months from the inlay augmentation procedure.
Material and Methods: Five subjects with severe atrophy of the posterior lower maxilla requiring bone reconstruction before implants placement were treated with an inlay procedure. At cone beam computed tomography (CBCT) the preoperative mean residual bone height above the mandibular canal was ≤ 7 mm, insufficient to place dental implants with adequate length. The inlay procedure provided the use of an allograft block. Three piezosurgical inserts were used to create a horizontal osteotomy at approximately 2–3 mm above the mandibular canal and two oblique cuts. An allograft bone block was then fitted between the
cranial osteotomized segment and the mandibular basal bone. A titanium miniplate was fixed with miniscrews. Two months after the inlay procedure, presence of adequate bone height was verified through CBCT scan and dental implants were placed.
During tunnel preparation for implants placement, a bone core biopsy was harvested and processed for histological and histomorphometric evaluations.
Results: Histological appearance of the regenerated bone areas was characterized by the presence of newly formed bone and large marrow spaces showing intense cellular activity but also features of mature bone, with well-organized lamellae and numerous osteocytes, revealing connection between the grafted material and the preexisting basal bone. High magnification views revealed the presence of lines of osteoblasts depositing the newly formed bone and this bone in contact with the allograft.
Conclusions and Clinical Implications: When treating severe atrophy of the posterior mandible, the use of allografts can be considered a suitable material for bone regeneration in the inlay grafting procedure in atrophic posterior mandibles, since it seems to permit implant rehabilitation after only two months from the grafting procedure. According to the preliminary results, this material represents a good clinical alternative to autologous and inorganic bovine bone
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