Basal Implant: A Remedy to Restore Resorbed Alveolar Ridges

The conventional crestal implants are used only when there is adequate jawbone height and width. Results of conventional implants are good in patients with healthy bone at the time of treatment, but prognosis gets deteriorated when surgical augmentation of bone is included with implant placement. These augmentation procedures have surgical risks and are costlier to the patients. Patients with atrophied jawbones are given no treatment, until crestal implants are seen as the last option. In this article, the indications for basal implants and functional differences between basal implants and crestal implants have been discussed.Patients with extreme jawbone atrophy do not benefit from crestal implants. The basal bone is the (cortical) osseous tissue of the mandible and maxilla, and lies below the alveolar process, which has a relatively strong and no resorbing framework.Basal osseointegrated and basal cortical screw (BCS) are two types of implants designed to take anchorage from the cortical bone of the jaw. BCS implants have long shafts and can be placed immediately in the socket after extraction and provided with immediate loading within 72 hours of implant placement. Basal implants are also called bicortical or cortical implants as they utilize the cortical portion of the jawbones for anchorage and implant stability. The basal bone has better quality and quantity of cortical bone for retention of these unique and highly advanced implants. The other names for these implants are lateral implants or disk implants.

The in vitro production of endochondral bone from bovine periosteal explants

In the present study, periosteal tissue explants were explored as a substratum for the production of endochondral bone tissue in vitro. Endochondral bone is formed when mesenchymal stem cells (MSCs) proceed through the chondrogenic lineage to produce a transitory cartilage template which eventually is ossified. The periosteum is of interest as this tissue is found enveloping long bones and has been shown to contain a resident cellular population capable of generating endochondral bone. Endochondral ossification was induced in periosteal explants through the successive application of chondrogenic and hypertrophic/osteogenic media simulating the in vivo progression of the process. Different chondrogenic and osteogenic media types were utilized in order to assess the best method for producing osseous tissue. The results indicated that endochondral bone could be produced from periosteum tissue in vitro. It was determined that chondrogenic culture with transforming growth factor β1 (TGFβ1) led to the development of immature (resting or proliferative) cartilage tissue while chondrogenic culture with bone morphogenetic protein 2 (BMP2) produced mature (hypertrophic or calcified) cartilage and osseous tissue. Osteogenic media generally failed to improve ossification in cartilaginous explants but did affect their progression through the endochondral process. Cartilaginous periosteum explants responded differently to osteogenic media types based on the method of chondrogenic pre-induction. Immature cartilage formed under TGFβ1 induction underwent maturation in osteogenic media with triiodothyronine (T3). Mature cartilage formed under BMP2 continued to undergo maturation in the presence of osteogenic media with BMP2 or T3. Overall, these findings suggested that BMP2 is crucial in the development of endochondral bone from periosteal explants in vitro and that the osteogenic media is unnecessary in promoting this process.

The in vitro production of endochondral bone from bovine periosteal explants

In the present study, periosteal tissue explants were explored as a substratum for the production of endochondral bone tissue in vitro. Endochondral bone is formed when mesenchymal stem cells (MSCs) proceed through the chondrogenic lineage to produce a transitory cartilage template which eventually is ossified. The periosteum is of interest as this tissue is found enveloping long bones and has been shown to contain a resident cellular population capable of generating endochondral bone. Endochondral ossification was induced in periosteal explants through the successive application of chondrogenic and hypertrophic/osteogenic media simulating the in vivo progression of the process. Different chondrogenic and osteogenic media types were utilized in order to assess the best method for producing osseous tissue. The results indicated that endochondral bone could be produced from periosteum tissue in vitro. It was determined that chondrogenic culture with transforming growth factor β1 (TGFβ1) led to the development of immature (resting or proliferative) cartilage tissue while chondrogenic culture with bone morphogenetic protein 2 (BMP2) produced mature (hypertrophic or calcified) cartilage and osseous tissue. Osteogenic media generally failed to improve ossification in cartilaginous explants but did affect their progression through the endochondral process. Cartilaginous periosteum explants responded differently to osteogenic media types based on the method of chondrogenic pre-induction. Immature cartilage formed under TGFβ1 induction underwent maturation in osteogenic media with triiodothyronine (T3). Mature cartilage formed under BMP2 continued to undergo maturation in the presence of osteogenic media with BMP2 or T3. Overall, these findings suggested that BMP2 is crucial in the development of endochondral bone from periosteal explants in vitro and that the osteogenic media is unnecessary in promoting this process.

Analysis of osseous tissue temperature during preparation of recipient bed for cylindrical implants

In the early 21st century, robot-assisted dental implant surgery became a popular alternative to classic implant placement protocols. Postoperative complications are often provoked by poor compliance with surgical guidelines for implant placement, resulting in the overheating of the osteotomy site. The aim of this study was to measure the temperature of osseous tissue at the dental implant site during classic and robot-assisted dental implant placement performed at different cooling modes. Avital skeletonized mandibles of Vietnamese pot-bellied pigs were used as an experimental model. The recipient bed was prepared following the classic surgical protocol. Three cooling modes were tested: no irrigation, irrigation with sterile saline at 25–30 ml/min and standard 75 ml/min irrigation recommended by the standard surgical protocol. The temperature of the isotonic solution was 25 °С. The study showed that both classic and robot-assisted dental implant placement techniques are safe if there is sufficient irrigation and good compliance with the surgical protocol.

THE ESTIMATION OF THE OSSEOUS TISSUE STATE IN DENTAL IMPLANTS SETTING, THEIR FUNCTIONING AFTER ORTHOPEDIC TREATMENT ACCORDING TO CLIMATIC AND GEOGRAPHICAL LOCATION

Subject. The study of the osseous tissue state in the dental implants setting, their functioning after the orthopedic treatment according to the climatic and geographical location. Aim of the study is to estimate the osseous tissue state in the dental implants setting, their functioning after the orthopedic treatment according to the climatic and geographical location. Methodology. The study regarding the estimation of the osseous tissue state after dental implants setting and subsequent orthopedic treatment taking them into consideration was carried out. The analysis of the medical documentation of 180 patients divided into 6 groups according to climatic and geographical location was made. The study was carried out using KBKT through definite control points to reveal the regularity of the region where the patients live, life conditions and the osseous tissue state. Results. The analysis of the received data showed that the patients living in Tyumen had the better osseous tissue state, the level of implants osseointegration and stability of the orthopedic constructions than the persons living in the north of Tyumen region. Conclusion. The level of the osseous tissue state after dental implants setting is different in the groups living in various climatic and geographical conditions including ones of the same region.

Dysuria Associated with Non-Neoplastic Bone Hyperplasia of the Os Penis in a Pug Dog

A three-year-old male Pug presented with a three-year history of urolithiasis and repeated urethral obstruction. Biochemical analysis, ultrasonography, and retrograde urethrocystography revealed probable portosystemic shunt and incomplete urethral obstruction due to uric acid ammonium calculi. Enhanced computed tomography (CT) revealed portosystemic shunt and proliferation of the osseous tissue of the os penis, which was surgically removed. Histopathologically, the excised osseous tissue comprised bland lamellar bone without atypia or inflammation. Hyperplasia of the os penis was diagnosed based on the image findings and histopathology. The dysuria improved postoperatively. This is the first report of dysuria associated with non-neoplastic bone hyperplasia of the os penis in a dog. Careful evaluation of the os penis by CT is needed for accurate diagnosis in case of repeated penile urethral obstruction.

Effects of Strontium-Doped β-Tricalcium Scaffold on Longitudinal Nuclear Factor-Kappa Beta and Vascular Endothelial Growth Factor Receptor-2 Promoter Activities during Healing in a Murine Critical-Size Bone Defect Model

It was hypothesized that strontium (Sr)-doped β-tricalcium phosphate (TCP)-based scaffolds have a positive effect on the regeneration of large bone defects (LBD). Readouts in our mice models were nuclear factor-kappa beta (NF-κB) activity and vascular endothelial growth factor receptor-2 (VEGFR-2) promoter activity during the healing process. A 2-mm critical-size femoral fracture was performed in transgenic NF-κB- and VEGFR-2-luciferase reporter mice. The fracture was filled with a 3D-printed β-TCP scaffold with or without Sr. A bioluminescence in-vivo imaging system was used to sequentially investigate NF-κB and VEGFR-2 expression for two months. After sacrifice, soft and osseous tissue formation in the fracture sites was histologically examined. NF-κB activity increased in the β-TCP + Sr group in the latter stage (day 40–60). VEGFR-2 activity increased in the + Sr group from days 0–15 but decreased and showed significantly less activity than the β-TCP and non-scaffold groups from days 40–60. The new bone formation and soft tissue formation in the + Sr group were significantly higher than in the β-TCP group, whereas the percentage of osseous tissue formation in the β-TCP group was significantly higher than in the β-TCP + Sr group. We analyzed longitudinal VEGFR-2 promoter activity and NF-κB activity profiles, as respective agents of angiogenesis and inflammation, during LBD healing. The extended inflammation phase and eventually more rapid resorption of scaffold caused by the addition of strontium accelerates temporary bridging of the fracture gaps. This finding has the potential to inform an improved treatment strategy for patients who suffer from osteoporosis.

Surgical resection for advanced bisphosphonate-related osteonecrosis of the jaw associated with fibrous dysplasia: a case report

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is an adverse drug reaction represented by destruction and/or death of bone. Fibrous dysplasia (FD) is a rare bony disorder characterised by abnormal fibro-osseous tissue that has lowered resistance to infection. Effective treatments for BRONJ that follows FD are unclear. Here, we report that advanced BRONJ associated with FD was successfully treated by surgical resection. A 69-year-old woman, whose left maxillary bone showed a ground glass appearance on computed tomography (CT) images, was taking alendronate. At 1 year after teeth within the abnormal bone were extracted, exposed bone was observed in the extraction sites and CT images revealed separated sequestrums. Under the clinical diagnosis of Stage 2 BRONJ with FD, we performed not only sequestrectomy but also a partial resection of the FD. Thereafter, the healing was uneventful without recurrence. In conclusion, our case suggests that surgical resection is useful for advanced BRONJ associated with FD.