International Journal of Periodontics & Restorative Dentistry, 1/2023
Online OnlyDOI: 10.11607/prd.5711Pages e35-e42, Language: English
Autogenous particulate bone grafts are being utilized in oral implantology for minor grafting procedures. This study aimed to investigate the influence of the bone-harvesting technique, donor age, and donor site on proliferation and differentiation of human primary osteoblast-like cells in the cell culture. Autogenous bone particles (20 samples) were harvested from the maxilla and mandible during surgery using two different protocols, and two types of particulate bone grafts were collected: bone chips and bone sludge. Bone samples were cultured in growth medium and, after 2 to 3 weeks, the cells that grew from bone grafts were cultured in the normal and osteogenic medium for 0, 4, 7, and 20 days. DNA, alkaline-phosphatase (ALP), calcium-content measurements, and Alizarin red/toluidine blue staining were performed. Data were analyzed by repeated-measures analysis of variance with Bonferroni test. The level of statistical significance was set at 5% (P < .05). Total DNA, ALP, and calcium content were significantly higher for the bone chip samples compared to the bone sludge samples. Total DNA and ALP content were significantly higher for the patients in age group 1 (≤ 60 years) compared to age group 2 (> 60 years) and was significantly higher for mandibular samples than maxillary samples on day 20. However, the calcium measurement showed no significant difference concerning donor age and donor site. Data analysis revealed that harvesting technique (bone chips vs bone sludge), donor age (≤ 60 years vs > 60 years), and donor site (maxilla vs mandible) influenced the osteogenic potential of the collected particulate bone graft. The bone chips were superior in terms of osteogenic efficacy and should be considered a suitable option for particulate bone graft collection.
The International Journal of Prosthodontics, 6/2021
DOI: 10.11607/ijp.7074Pages 733-743, Language: English
Purpose: To compare the fit and clinical performance of screw-retained monolithic zirconia implant fixed dental prostheses (FDPs) based on either intraoral optical scanning (IOS) or conventional impressions.
Materials and methods: Patients with two posterior tissue-level implants (Straumann Regular Neck) replacing two or three adjacent teeth were recruited. Impressions were taken with both IOS (True Definition Scanner, 3M ESPE) and a conventional (polyether) pick-up impression. Double-blind randomization was performed after impression-taking, and patients were to receive an FDP based on either the digital or the conventional impression. The fit was evaluated, and the time required for adjustments was recorded. Additionally, survival and technical complication rates with a follow-up of 1 year were documented.
Results: A total of 38 patients requiring 45 FDPs were included: 24 FDPs in the test (IOS) and 21 in the control (conventional) group. The average adjustment time was 6.92 minutes (SD: ± 10.84, range: 0 to 49 minutes) for digital vs 12.38 minutes (SD: ± 14.52, range: 0 to 54 minutes) for conventional impressions (P = .090). A proper fit (no adjustments) was achieved in 33.3% of the digital and 28.6% of the conventional group. Forty-two FDPs could be placed within the two planned appointments, and 3 FDPs exhibited an unacceptable fit and required an extra appointment. Eight technical complications occurred during the first year of function. The overall restoration survival rate was 100%.
Conclusion: The clinical fit of CAD/CAM FDPs based on digital impressions is comparable to conventional impressions. Screw-retained monolithic zirconia FDPs on Ti-base abutments show low major complication and survival rates in the short term.
The International Journal of Oral & Maxillofacial Implants, 6/2021
Online OnlyDOI: 10.11607/jomi.9029Pages e175-e182, Language: English
Purpose: There is a substantial need to perform studies to evaluate crestal bone loss (CBL) and implant success when using a newly introduced low-speed drilling protocol. Therefore, this study aimed to evaluate the mean CBL and implant success rate by placing implants utilizing two drilling protocols, ie, standard and low-speed drilling protocols.
Materials and methods: A randomized controlled clinical trial was carried out in patients who required dental implants to restore their esthetics and function. The patients were recruited from a university hospital (Academic Centre for Dentistry Amsterdam [ACTA], the Netherlands). Based on the inclusion criteria, patients were randomized to two study groups: (1) control group, standard drilling protocol; and (2) test group, low-speed drilling protocol without saline irrigation. The mean CBL and the implant success rate were evaluated after 12 months of implant placement.
Results: Twenty-three patients (15 men and 8 women with a mean age of 57.5 ± 10.7 years) contributed to the study. Forty Camlog screw-line implants were placed (20 implants per study group). After 12 months of implant placement, the mean CBL of implants placed with the standard protocol and the low-speed protocol was 0.206 ± 0.251 mm and 0.196 ± 0.178 mm, respectively. No statistically significant difference could be recorded among both groups (P = .885). Concerning implants placed in the maxilla, the standard drilling group and low-speed drilling group showed a mean CBL of 0.252 ± 0.175 mm and 0.251 ± 0.175 mm, respectively, compared with 0.173 ± 0.210 mm and 0.141 ± 0.172 mm in the mandible, with no significant difference. The success rate of dental implants at 12 months was 95% in the control group and 90% in the test group.
Conclusion: Within the limitations of this study, it can be concluded that implants placed with the low-speed drilling protocol without saline irrigation exhibited a similar CBL compared with implants placed with the standard drilling protocol. However, a higher success rate was recorded especially in type 1-quality bone for the control group compared with the test group. Further randomized clinical trials with greater sample sizes and extended follow-up times should be performed to obtain stronger evidence and a better understanding of the influence of drilling speed on mean CBL and long-term implant success.
Keywords: crestal bone loss, dental implant, low-speed drilling, standard drilling
The International Journal of Oral & Maxillofacial Implants, 1/2020
DOI: 10.11607/jomi.7648, PubMed ID (PMID): 31184630Pages 141-149, Language: English
Purpose: Autogenous bone grafts are considered a "gold standard." The success of autografts mainly depends on their ability to promote an osteogenic response. The aim of this study was to collect autogenous bone during implant osteotomy preparation using two different drilling protocols and to evaluate and compare the proliferation and differentiation ability of the collected bone particles.
Materials and Methods: Autogenous bone particles were harvested from 20 patients during implant osteotomy preparation using two different drilling protocols: (1) standard drilling protocol with saline irrigation (according to the manufacturer's recommendation) and (2) low-speed drilling protocol without saline irrigation (speed < 200 rpm). Collected bone samples were cultured in growth medium, and after 2 to 3 weeks, cells that grew out from bone grafts were cultured in the normal medium as well as in osteogenic medium for days 0, 4, 7, and 20. Scanning electron microscopy, alizarin red/toluidine blue staining, DNA, ALP, and calcium content measurements were performed. Repeated measures analysis of variance (ANOVA) with Bonferroni's test was employed to analyze the data of this study.
Results: The total DNA content was significantly higher for the low-speed drilling samples compared with the standard drilling on day 4 (P < .05), day 7 (P < .01), and day 20 (P < .001) in the normal medium and on day 7 (P < .01) and day 20 (P < .01) in the osteogenic medium. Besides, calcium measurements and mineralized matrix formation observed with alizarin red/toluidine blue staining were significantly higher for the low-speed drilling group compared with the standard drilling group.
Conclusion: Osteogenic efficacy (differentiation and proliferation) of autogenous bone particles collected using low-speed drilling was superior compared with standard drilling samples.
Keywords: bone graft(s), bone remodeling/regeneration, cell differentiation, dental implants, mineralized tissue/development, osteoblast
International Journal of Periodontics & Restorative Dentistry, 3/2019
DOI: 10.11607/prd.3980, PubMed ID (PMID): 30986287Pages 371-379, Language: English
This study aimed to histologically investigate the bone tissue response to zirconia implants functionalized with a biomimetic calcium phosphate (CaP) coating incorporated with bone morphogenetic protein-2 (BMP-2). Zirconia implants coated with biomimetic CaP were prepared with and without BMP-2. Untreated zirconia implants served as a control. These three groups of implants were placed randomly in the mandibles of six beagle dogs (n = 6). Three months later, samples were harvested for histomorphometric analysis. The present study showed that the application of a biomimetic CaP coating incorporated with BMP-2 enhanced the peri-implant osteogenesis for zirconia implants.
The International Journal of Oral & Maxillofacial Implants, 2/2019
DOI: 10.11607/jomi.6980, PubMed ID (PMID): 30883624Pages 481-488, Language: English
Purpose: This cohort study evaluated patient satisfaction for maxillary implant-retained overdentures (IODs) on two implants up to 4 years and assessed the treatment effect over time.
Materials and Methods: Patients encountering problems with their conventional dentures were included and received maxillary IODs on two titanium-zirconium implants and ball anchors in the canine area. Patient satisfaction was assessed using the oral health impact profile (OHIP-20E) questionnaires both for dentures and IODs. Two months after insertion of IODs (baseline), the patients chose the preferred overdenture design with full or reduced palatal coverage. OHIP-20E questionnaires were followed according to the individual choice at 1 and 4 years, and outcomes were compared with baseline.
Results: Sixteen out of 21 patients were evaluated at a mean follow-up of 4 years (range: 2.4 to 4.8 years). There was no significant difference in the OHIP domains for IODs at 1 year (OHIP_total_1y: 9.5, SD: 13.0) and 4 years (OHIP_total_4y: 14.2, SD: 19.1) compared with baseline (OHIP_total_BL: 12.4, SD: 14.7). Patients were most satisfied with social disability both for IODs (OHIP_BL: 6.0, SD: 7.6; OHIP_1y: 3.4, SD: 5.4; OHIP_4y: 5.7, SD: 9.5) and dentures (OHIP_CD_old: 28, SD: 29.7; OHIP_CD_new: 25.4, SD: 28.67). Patients were least satisfied with functional limitation both for IODs (OHIP_BL: 6.0, SD: 7.6; OHIP_1y: 3.4, SD: 5.4; OHIP_4y: 5.7, SD: 9.5) and dentures (OHIP_CD_old: 28, SD: 29.7; OHIP_CD_new: 25.4, SD: 28.67).
Conclusion: Patient satisfaction with maxillary IODs on two implants did not change from baseline to 4 years and was high at 4 years of function.
Keywords: dental implants, dental prosthesis, edentulous, implant-supported, jaw, maxilla, overdenture, patient-reported outcomes, patient satisfaction, quality of life
Pages 110-117, Language: English
Computer Aided Implant Surgery (CAIS) has lately been gaining popularity among dental clinicians. Several software packages and associated tools are available on the market. Recent literature reviews show that inaccuracies often occur when these techniques are applied. In this article, the authors give an overview of the tools available for CAIS along with their benefits and shortcomings as well as possible solutions to improve overall accuracy in CAIS.
Keywords: Guided surgery, computer planning, CAIS
QZ - Quintessenz Zahntechnik, 2/2018
Pages 170-186, Language: German
In der Prothetik werden verschiedene additive Fertigungsverfahren zur Herstellung von Gerüsten festsitzender Restaurationen, Metallgerüsten herausnehmbarer Teilprothesen sowie von Kunststoff-Mock-ups und Kunststoffmodellationen für den klassischen Metallguss eingesetzt. Die additive Fertigung erweist sich hier als vielversprechend, auch wenn ihre Anwendung noch Einschränkungen unterliegt. Eine Beschäftigung mit diesen Grenzen und aktuellen Entwicklungen der Werkstoffkunde ist unerlässlich, bevor die additive Fertigung als akzeptables Herstellungsverfahren für Zahnersatz gelten darf.
Keywords: Additive Fertigungsverfahren, 3-D-Druck, Prothetik, Gerüstherstellung, Review
The International Journal of Oral & Maxillofacial Implants, 2/2018
Online OnlyDOI: 10.11607/jomi.6048, PubMed ID (PMID): 29534136Pages e37-e44, Language: English
Purpose: To evaluate the feasibility of a commercially available immediate root analog implant system Replicate (Natural Dental Implants).
Materials and Methods: Five consecutive patients in need of an implant in the premolar region were recruited for this pilot study. Following clinical examination, a cone beam computed tomography scan was made and the dental impressions digitized. On the basis of the superimposition of these datasets, a three-dimensional (3D) envelope was created for the selected tooth. Subsequently, the tooth root at the prospective implant site was segmented to create a 3D surface, and the obtained mesh data were used as the basis for designing a single-piece root analog implant within the 3D envelope. The designed root analog implant was fabricated using a five-axis computer-aided manufacturing machine. The root analog implants were inserted following flapless minimally invasive root extraction. Following 3 months of uninterrupted healing, definitive restorations were fabricated. Peri-implant clinical and radiographic measurements were obtained up to 12 months follow-up.
Results: All patients functioned well following 12 months of functional loading. Within one patient, one of the two root analog implants failed early. Peri-implant clinical and radiographic measurements demonstrated a stable situation after 12 months of functional loading.
Conclusion: A novel digital approach for immediately restoring single teeth using root analog implants was introduced. In the future, long-term evaluation of the root analog implant technique is necessary to evaluate the success and survival of implants that were inserted using this technique.
Keywords: CAD/CAM, CBCT, custom implants, digital dentistry, 3D planning
The International Journal of Oral & Maxillofacial Implants, 1/2018
DOI: 10.11607/jomi.6009, PubMed ID (PMID): 29340354Pages 197-205, Language: English
Purpose: The aim of this 1-year randomized trial was to determine the stability and the magnitude of the effect of converting patients' conventional mandibular dentures to implant overdentures (IODs) on their satisfaction and oral health-related quality of life (OHRQoL). The IODs were retained either with two immediately loaded interconnected standard-diameter implants or with four immediately loaded mini dental implants (MDIs).
Materials and Methods: Fifty completely edentulous subjects complaining about insufficient retention of their mandibular dentures were randomly assigned to two groups; 25 patients received IODs retained with four MDIs and 25 patients received IODs retained with two standard-sized tissue level (STL) interconnected implants. All IODs were opposed by conventional maxillary dentures. Patients rated their satisfaction on a 100-mm visual analog scale (VAS) and their quality of life on a denture-specific short version of the oral health impact profile (OHIP-20) before assignment, and after 3 and 12 months. A two-way mixed analysis of variance (ANOVA) was conducted to assess the change in time and its interaction with treatment mode on patients' overall satisfaction ratings, the total OHIP-20, and their specific domain scores.
Results: Immediate loading was possible for all the patients who received the MDIs. By contrast, the immediate loading protocol could be followed for only 15 of the patients allocated to the STL implant group. For the remaining patients, a delayed loading protocol was applied. There was a significant improvement in patients' general satisfaction between baseline and 3 months and between baseline and 12 months postoperatively (F2,44 = 81.006, P < .001). This increase did not differ between the treatment groups (F4,90 = 1.838, P = .128). The results also showed a decrease in mean overall OHIP score (F2,43 = 46.863, P < .001) between baseline and 3 months and between baseline and 12 months postoperatively, indicating a higher level of OHRQoL. In addition, patients scored lower 3 and 12 months after treatment than at baseline for all seven domains. This decrease did not differ between the treatment groups (F4,88 = 0.608, P = .658).
Conclusion: The results suggested that in terms of patient-based outcomes, mandibular overdentures retained by immediately loaded MDIs can offer an improvement of equal magnitude with that achieved by overdentures retained by standard-sized implants.
Keywords: immediate loading, mini dental implants, OHIP-20, VAS