Osseous Coagulum Research Articles

Osseous Coagulum in the Placement of Immediate Implant

Loss of tooth causes more of a psychological trauma to the patient tha n functional loss, particularly if the tooth loss is in the aesthetic segment. Traditional protocols suggested a consolidation period of 3-4 months before placing dental implants. Immediate implant placement, defined as the placement of dental implant immediately into fresh extraction socket site after tooth extraction, has been considered a predictable and acceptable procedure.

A Novel Osteotomy Preparation Technique to Preserve Implant Site Viability and Enhance Osteogenesis.

The preservation of bone viability at an osteotomy site is a critical variable for subsequent implant osseointegration. Recent biomechanical studies evaluating the consequences of site preparation led us to rethink the design of bone-cutting drills, especially those intended for implant site preparation. We present here a novel drill design that is designed to efficiently cut bone at a very low rotational velocity, obviating the need for irrigation as a coolant. The low-speed cutting produces little heat and, consequently, osteocyte viability is maintained. The lack of irrigation, coupled with the unique design of the cutting flutes, channels into the osteotomy autologous bone chips and osseous coagulum that have inherent osteogenic potential. Collectively, these features result in robust, new bone formation at rates significantly faster than those observed with conventional drilling protocols. These preclinical data have practical implications for the clinical preparation of osteotomies and alveolar bone reconstructive surgeries.

Clinical Application of Platelet-Rich Fibrin by the Application of the Double J Technique During Implant Placement in Alveolar Bone Defect Areas

Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates, with simplified processing and without biochemical blood handling. PRF releases growth factors and matrix glycoproteins. In this study, the Double J technique was used. The Double J technique, which uses centrifuged venous blood that is sampled using 2 different types of DB vacutainers, is a procedure that covers the PRF matrix obtained from 1 of the DB vacutainers on transplanted osseous coagulum, which is obtained using the plasma layer and buffering layer from the second DB vacutainer. Two cases were reported because clinically valid results were obtained. Additional studies are definitely warranted.

Osseous Coagulum Collected in Bone Traps: Potential for Bacterial Contamination and Methods for Decontamination

Because of its excellent osteogenic potential, autogenous bone is the preferred grafting material for dental procedures; however, bone collected in osseous coagulum traps is subject to contamination by oral bacteria. This study assessed bacterial contamination of osseous coagulum and tested treatments for reducing contamination. Fifty bone samples from patients undergoing implant osteotomy procedures were collected in osseous coagulum traps, divided into groups of 10, and rinsed with normal saline, 0.12% chlorhexidine, or 50 mg/mL tetracycline. Twenty control samples received no treatment. The bone samples were plated in triplicate on selective and differential media to assay aerobic and anaerobic bacteria and potential bacterial pathogens, including staphylococci, streptococci, enterics, and black-pigmented bacteria (BPB). Inoculations were performed with an Autoplate 4000, and plates were incubated at 37 degrees C either aerobically or in a Coy anaerobic chamber. Bacteria were isolated from all samples. In control samples, the mean colony-forming units (cfu) per milliliter of suspended osseous coagulum was 6.5 x 10(4) +/- 9.6 x 10(4) in aerobic cultures and 4.8 x 10(4) +/- 6.9 x 10(4) in anaerobic cultures. Viridans streptococci were isolated from 46 samples, with a mean of 2.9 x 10(4) +/- 4.1 x 10(4) cfu/mL. Enterics were in 16 samples with cfu ranging from 200 cfu/mL to 3.4 x 10(4) cfu/mL. Mannitol nonfermenting staphylococci were found in one sample at 106 cfu/mL. BPB were not isolated. A Mann-Whitney U test with significance set at P = .05 determined that the only statistically significant reductions in bacterial numbers occurred in tetracycline-treated samples of anaerobic bacteria (5-fold decrease, P = .02) and aerobic bacteria (6-fold decrease, P = .01). Tetracycline treatments effected a 7-fold decrease in streptococci, but the difference was not significant (P = .07). These data indicate significant bacterial contamination of bone collected in osseous coagulum traps and justify further research into methods for eliminating that contamination.

Performance of six bone collectors designed for dental implant surgery

The aim of this study was to perform an in vitro comparison of six bone collectors for harvesting of particulate bone. Four commercially available bone collectors (Frios, Osseous Coagulum Trap, ACE Autografter, Bone Trap) and two custom-designed models were tested. Three different in vitro tests were performed to determine the harvesting capabilities of the collectors. In test I, a bovine mandible was drilled and the bone collectors were used to collect bone chips. The harvested bone volumes and dry weights were measured after harvesting. In test II, three dental implant sites were prepared in a bovine mandible. The bones from the implant osteotomies were collected, and bone volumes and dry weights were measured. In test III, 1 ml of bone chips was mixed with water, and suctioned through the bone collectors. The volumes of the bone chips retained were measured to determine the efficiency of each collector. The Osseous Coagulum Trap and the custom-made collectors were the most effective instruments in test I. The mean volumes ranged from 0.17 to 0.38 ml. In test II, the difference between the collectors was small and the bone volume ranged from 0.28 to 0.37 ml. In test III, the Bone Trap became blocked before the other collectors, and its bone procurement was therefore limited. Comparison of six different bone collectors in this in vitro study showed that all collectors are usable in clinical situations but their effectiveness varies.

Implant Placement at the Time of Maxillary Molar Extraction: Technique and Report of Preliminary Results of 83 Sites

The purpose of this study was to evaluate the predictability of implant placement at the time of maxillary molar extraction using a modified insertion technique and implant design. At the time of maxillary molar extraction, 83 tapered-end implants with an apical diameter of 4.1 mm and a neck diameter of 6.5 mm were placed in maxillary first or second molar sites, following manipulation of the remaining interradicular bone with osteotomes. Regenerative materials, consisting of demineralized freeze-dried bone allograft (DFDBA) and/or osseous coagulum, and bioabsorbable or non-resorbable membranes were placed, and passive soft-tissue primary closure was attained in all cases. Soft-tissue closure was maintained until the time of clinical reentry 6 months after implant insertion in 81 of 83 sites. Loss of primary soft-tissue closure in the other two areas did not result in complete uncovering of the cover screw and implant top. All implants were clinically immobile at the time of implant uncovery 6 months after insertion and were restored with single crowns. All implants were functioning successfully for up to 18 months (mean: 12.4 months). The combination of atraumatic removal of hopeless maxillary molars, controlled manipulation of the residual interradicular bone, insertion of implants of the aforementioned design, and use of appropriate regenerative materials at the time of implant insertion predictably afforded a stable implant for restoration with a single crown.

Viability of autogenous bone grafts obtained by using bone collectors: histological and microbiological study.

The use of autogenous bone grafts is considered to be the best choice for reconstructive surgery. In the periodontal literature, the utilization of osseous coagulum was suggested by the end of the sixties. The purpose of this study is to consider the use of bone collectors (bone traps) as an alternative method for obtaining material to fill small bone imperfections, such as fenestrations and dehiscences. Thirty samples were obtained from bone drilling during fixture installation in patients (13 men and 17 women, with an average age of 54 years) requiring treatment at the Department of Periodontology and Implant Dentistry, University of Santo Amaro. These samples were fixed in 10% neutral formaldehyde for 24 hours and subjected to histological preparation, in order to evaluate the presence of viable osteoblasts. In addition, the material was placed in a fluid thioglycolate medium and incubated for 24 hours at 36 1 C in aerobiosis and anaerobiosis. Bacterial growth evaluation was made by using six different culture media (MacConkey agar, blood agar base, mannitol salt agar, Anaerokit LTD medium, Anaerokit LTD - bile medium, Anaerinsol). The results show that, if proper care is taken to prevent saliva contamination during the surgical procedure, this method of collecting autogenous bone may be useful in situations where small amounts of bone are required.

A new filter for osseous coagulum collection.

A filter which can be sued for the collection of osseous coagulum is described. The filter is a stainless steel screen in a plastic housing, which does not require the addition of cloth or membrane filters. It is compact, autoclavable, and reusable.

The value of osseous coagulum as a graft material.

Osseous coagulum is regarded by some clinicians as a useful material for grafting in procedures aimed at bone replacement. Its value in this regard has been assessed experimentally. Holes ∼ 2 mm in diameter were made in the right and left parietal bones of 15 middle‐aged Wistar‐strain albino rats weighing ∼ 500 g. Osseous coagulum was obtained from the interparietal bone, and was placed into the left hole, while the right served as a control. Three of the animals were injected with tetracycline; these animals were sacrificed at 4, 8 and 12 weeks postoperatively, and undemineralized sections of their calvaria were viewed in ultraviolet light to assess accretion of new bone. The remaining 12 animals were sacrificed at postoperative intervals of 1, 2, 3, 4, 8 and 12 weeks, and serial sections of their calvaria were examined by routine histological methods. The observations indicate that, in this system in which repair is normally poor, osseous coagulum consistently did not appear to have induced the formation of new bony callus. These findings bring into question the value of using osseous coagulum as an autograft in clinical periodontal procedures aimed at restoring the attachment apparatus.

Autogenous bone grafts: osseous coagulum and osseous retrograde procedures in primates.

Autogenous bone grafts: osseous coagulum and osseous retrograde procedures in primates.

Osseous coagulum for bone induction.

Osseous coagulum for bone induction.