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

An Osteotomy Tool That Preserves Bone Viability: Evaluation in Preclinical and Clinical Settings

The main objectives of this work were to assess the efficiency, ease-of-use, and general performance of a novel osseoshaping tool based on first-user clinical experiences and to compare these observations with preclinical data generated in rodents using a miniaturized version of the instrument. All patients selected for the surgery presented challenging clinical conditions in terms of the quality and/or quantity of the available bone. The presented data were collected during the implant placement of 15 implants in 7 patients, and included implant recipient site (bone quality and quantity) and ridge evaluation, intra-operative handling of the novel instrument, and the evaluation of subsequent implant insertion. The instrument was easy to handle and was applied without any complications during the surgical procedure. Its use obviated the need for multiple drills and enabled adequate insertion torque in all cases. This biologically driven innovation in implant site preparation shows improvements in preserving vital anatomical and cellular structures as well as simplifying the surgical protocol with excellent ease-of-use and handling properties.

Examination of the Quality of Particulate and Filtered Mandibular Bone Chips for Oral Implants: An In Vitro Study

(1) Background: Autologous bone is supposed to contain vital cells that might improve the osseointegration of dental implants. The aim of this study was to investigate particulate and filtered bone chips collected during oral surgery intervention with respect to their osteogenic potential and the extent of microbial contamination to evaluate its usefulness for jawbone reconstruction prior to implant placement. (2) Methods: Cortical and cortical-cancellous bone chip samples of 84 patients were collected. The stem cell character of outgrowing cells was characterized by expression of CD73, CD90 and CD105, followed by osteogenic differentiation. The degree of bacterial contamination was determined by Gram staining, catalase and oxidase tests and tests to evaluate the genera of the found bacteria (3) Results: Pre-surgical antibiotic treatment of the patients significantly increased viability of the collected bone chip cells. No significant difference in plasticity was observed between cells isolated from the cortical and cortical-cancellous bone chip samples. Thus, both types of bone tissue can be used for jawbone reconstruction. The osteogenic differentiation was independent of the quantity and quality of the detected microorganisms, which comprise the most common bacteria in the oral cavity. (4) Discussion: This study shows that the quality of bone chip-derived stem cells is independent of the donor site and the extent of present common microorganisms, highlighting autologous bone tissue, assessable without additional surgical intervention for the patient, as a useful material for dental implantology.

Preventive antibiotic therapy in bone augmentation procedures in oral implantology: A systematic review

INTRODUCTION

Since the beginning of Oral Implantology, preventive antibiotic therapy has been routinely prescribed. However, at present, due to the growing appearance of antimicrobial resistance, its use has been questioned, generating a great debate and an emerging controversy. The present systematic review aims to analyze the scientific literature to determine whether the preventive prescription of antibiotics in augmentation procedures with the insertion of implants in one or two phases decreases the incidence of postoperative infections and/or the survival rate of the implants.

MATERIAL AND METHODS

The MEDLINE database was searched (via PubMed) with the following keywords: (bone grafting OR alveolar ridge augmentation OR bone graft augmentation OR guided bone regeneration OR bone block) AND (dental implants OR dental implant OR oral implantology) AND (antibiotic prophylaxis OR antibiotics). The criteria used were those described by the PRISMA® Statement. The search was limited to randomised clinical trials, systematic reviews and meta-analyses published in the last 15 years (2005-2020).

RESULTS

After reading the titles and abstracts of the resulting articles, only one systematic review meeting the described criteria and 4 randomised clinical trials were included.

CONCLUSIONS

Prescription of 2 or 3 g of amoxicillin one hour before surgery is recommended to reduce the early failure rate of one-stage implants and to decrease the bacterial load of grafted bone particles in bone augmentation procedures with one or two-stage implants.

Efficacy of low-dose local clindamycin in different times for microbial decontamination of autogenous particulate bone graft

BACKGROUND

Clindamycin in low concentration (20 μg/mL) is safe for vitality and osteogenic potential of bone cells. The aim of this study was to evaluate the efficacy of local clindamycin (20 μg/mL) in two different exposure times, for microbial decontamination of particulate bone graft, collected during implant site preparation. This non-randomized parallel-group study was conducted on samples from 17 patients. The particulate bone collected during implant site preparation was divided into three portions by weight: in group S1, the particulate bone was immersed in thioglycolate broth without any antibiotic treatment; in group S2, the collected particulate bone was irrigated with 100 mL clindamycin solution (20 μg/mL); and in group S3, the collected particulate bone was soaked in one ml clindamycin solution (20 μg/mL) for 3 min. Samples in the three groups were cultured in aerobic and anaerobic media and species and CFU count of isolated bacteria were determined.

RESULTS

Analysis of the data demonstrated a significant difference among the three groups in the mean count of total microorganisms (P = 0.001). The difference in the mean count of anaerobic and aerobic microorganisms in the three groups was statistically significant as well (P = 0.001). Pseudomonas aeruginosa was the only microorganism that was not affected with the mentioned antibiotic.

CONCLUSIONS

Local use of low-dose clindamycin (20 μg/mL)-irrigation or 3 min immersing-is effective for the decontamination of particulate bone grafts.

Microbiological analysis of autologous bone particles obtained by low-speed drilling and treated with different decontamination agents

The aim of this study was to compare the effectiveness of three agents - two antibiotics (amoxicillin and clindamycin) and an antiseptic (chlorhexidine) - to decontaminate bone grafts obtained by low-speed drilling. The study included 248 bone tissue samples harvested from 62 patients by low-speed drilling before dental implant placement. Each of four samples obtained from every patient was dropped, using a sterile instrument, into a sterile tube containing a 500-μl solution of 400μg/mL amoxicillin, 150μg/mL clindamycin, 0.12% chlorhexidine, or physiological saline for 1min. The number of colony-forming units (CFU) was determined at 48h of culture. The use of clindamycin, amoxicillin, or chlorhexidine as decontaminant for 1min significantly reduced the CFU count when compared to physiological saline (control agent). In both anaerobic and CO₂-rich atmospheres, significant differences in CFU/mL were found between the control and chlorhexidine groups (P<0.001), control and amoxicillin groups (P<0.001), control and clindamycin groups (P<0.001), chlorhexidine and amoxicillin groups (P<0.0001), and chlorhexidine and clindamycin groups (P<0.0001). In conclusion, clindamycin had the highest decontaminating effect on bone particles obtained by low-speed drilling, followed by chlorhexidine and amoxicillin. Clindamycin may therefore be a valid alternative option for the routine decontamination of intraoral bone grafts.

Effects of Antiseptic Solutions Commonly Used in Dentistry on Bone Viability, Bone Morphology, and Release of Growth Factors

PURPOSE

Antiseptic solutions are commonly used in dentistry for a number of sterilization procedures, including harvesting of bone chips, irrigation of extraction sockets, and sterilization of osteonecrotic bone. Despite its widespread use, little information is available regarding the effects of various antiseptic solutions on bone cell viability, morphology, and the release of growth factors.

MATERIALS AND METHODS

The antiseptic solutions included 1) 0.5% povidone iodine (PI), 2) 0.2% chlorhexidine diguluconate (CHX), 3) 1% hydrogen peroxide (H2O2), and 4) 0.25% sodium hypochlorite (HYP). Bone samples collected from porcine mandibular cortical bone were rinsed in the antiseptic solutions for 10 minutes and assessed for cell viability using an MTS assay and protein release of transforming growth factor (TGF-β1), bone morphogenetic protein 2 (BMP2), vascular endothelial growth factor (VEGF), interleukin (IL)-1β, and receptor activator of nuclear factor κB ligand (RANKL) using an enzyme-linked immunosorbent assay at 15 minutes and 4 hours after rinsing.

RESULTS

After antiseptic rinsing, changes to the surface protein content showed marked alterations, with an abundant protein layer remaining on CHX-rinsed bone samples. The amount of surface protein content gradually decreased in the following order: CHX, H2O2, PI, and HYP. A similar trend was also observed for the relative cell viability from within bone samples after rinsing, with up to 6 times more viable cells found in the CHX-rinsed bone samples than in the HYP- and PI-rinsed samples. An analysis of the growth factors found that both HYP and PI had significantly lower VEGF and TGF-β1 protein release from bone samples at 15 minutes and 4 hours after rinsing compared with CHX and H2O2. A similar trend was observed for RANKL and IL-1β protein release, although no change was observed for BMP2.

CONCLUSIONS

The results from the present study have demonstrated that antiseptic solutions present with very different effects on bone samples after 10 minutes of rinsing. Rinsing with CHX maintained significantly higher cell viability and protein release of growth factors potent to the bone remodeling cycle.

Mandibular tori as bone grafts: an alternative treatment for periodontal osseous defects - clinical, radiographic and histologic morphology evaluation

OBJECTIVES

The present study was designed to evaluate the clinical, radiographic and histochemical significance of using the mandibular tori as autogenous bone graft for treatment of intraosseous defects in patients with chronic periodontitis.

MATERIALS AND METHODS

Twenty-eight sites from 14 patients with chronic periodontitis were included in this study. Each patient was treated with split mouth design; one site received torus mandibularis bone graft and the other site received a full-thickness fap alone. Histopathologic assessment was evaluated on removal of torus mandibularis to evaluate its histologic structure and by the end of the study 9 month later. Clinical and radiographic parameters were re-evaluated at 3 months interval for 1 year.

RESULTS

The results of the present study revealed significant gain in the clinical attachment level (CAL) (88.4%, 4.53 ± 0.06 mm) for torus mandibularis sites compared to (39.7%, 2.01 ± 0.04 mm) for full-thickness fap. Moreover, there was a reduction in the probing pocket depth (PPD) of (75.4%, 5.75 ± 0.12 mm) for torus mandibularis sites and (49.6%, 3.73 ± 0.14 mm) for sites treated with a full-thickness fap only; CAL and PPD differences were significant at p-value ≤0.01. Concomitantly, significant radiographic increase in the bone height and density were recorded in the test group.

CONCLUSION

The use of mandibular tori as autogenous bone graft could provide benefits as a periodontal therapeutic modality and enhance regenerative potential of periodontal intraosseous defects.

Effect of clinical factors on bacterial contamination of bone chips collected during implant surgery

PURPOSE

The objective of this study was to investigate the relationship between various clinical factors and bacterial contamination of bone chips (BC) collected during dental implant surgery and to elucidate how bacterial contamination might be minimized.

MATERIALS AND METHODS

Implants were installed in 55 partially edentulous patients (36 men and 19 women), among whom the relationship between various clinical factors and bacterial contamination of BC collected by bone trap was investigated in 37. The effect of rinsing with a saline on BC was determined in 18 patients. Number of contaminating microorganisms was expressed as colony-forming units (CFUs).

RESULTS

CFUs in the maxilla were lower than those in the mandible (P < 0.01). CFUs at the incisors or canines were lower than those at the premolars or molars (P < 0.01). Logistic regression analysis revealed a relationship between average bacterial count and duration of surgery (odds ratio, 1.046; 95% CI, 1.012-1.081). Rinsing of BC reduced bacterial contamination.

CONCLUSION

Duration of surgery is a major clinical factor affecting contamination risk in BC, and rinsing of BC with a sterile saline solution reduces bacterial number.

Morphology of bone particles after harvesting with 4 different devices

INTRODUCTION

Autogenous bone is routinely used for regeneration of osseous defects around teeth and implants, and different instruments are available for bone harvesting.

OBJECTIVES

The purpose of this study was to describe the morphology of bone particles after harvesting with 4 different instruments.

MATERIALS AND METHODS

Bone particles were harvested from fresh cow ribs with 2 different types of back action chisels, a safescraper and a sonic device. The samples were examined morphologically using light microscopy and scanning electron microscopy.

RESULTS

The bone particles after the back action chisel I had an appearance similar to "pencil shavings." With the back action chisel II, they were like thin paper with an "accordion bellows" appearance. After removal with the safescraper, they had an irregular shape (with an irregular surface) resembling "crushed stone." Finally, the appearance of the bone particles obtained with the sonic device was homogenous, condensed and continuous, and had a "seaweed" appearance.

CONCLUSIONS

Harvesting of bone particles with 4 different devices produce distinctly difference sizes and shapes, which may influence the results of grafting procedures.

Treatment of peri-implantitis with deproteinised bovine bone and tetracycline: a case report

OBJECTIVE

The objective of this study is to evaluate the use of tetracycline in a patient with peri-implantitis.

BACKGROUND

Tetracycline is widely used in regeneration procedures owing to its positive effect with bone graft material, regeneration of extraction socket bone and its traditional antibacterial effect. However, there have been limited reports on bone graft procedures combined with tetracycline application in peri-implantitis.

MATERIALS AND METHODS

The detoxification procedure was performed with chlorhexidine and tetracycline, and the defect area was grafted with a 4:1 volume ratio combination of deproteinised bovine bone mixed with tetracycline.

RESULTS

Soft tissue healing was uneventful, and the treatment yielded improved clinical results with a reduced probing depth.

CONCLUSIONS

Tetracycline was used in the treatment of peri-implantitis by burnishing the implant surface and applying tetracycline in conjunction with an osseous graft to the defect area. The treatment of peri-implantitis with tetracycline seemed to show improved clinical results up to the follow-up period.