The number of implants and their respective configurations for implant-supported treatment modalities have been studied for 4 implant-supported prostheses; however, it is not yet clear whether the use of tilting or short...The number of implants and their respective configurations for implant-supported treatment modalities have been studied for 4 implant-supported prostheses; however, it is not yet clear whether the use of tilting or short implants in rehabilitation would result in substantially improved bone/implant/prosthesis biomechanics in all-on-six concepts. This study compared the biomechanical behavior of tilted long implants and axially short implants to support fixed prostheses in an atrophic maxilla with all-on-six treatment concepts. Three different implant configurations were planned, and six models were obtained with posterior maxilla D3 and D4 bone densities in this study. Implants proper for the all-on-four concept were placed in all models. In models 1 and 2, the short implant was placed; in models 3 and 4, 30°, the mesial-angled implant was placed; and in models 5 and 6, 45°, the mesial-angled implant was placed to the molar region. In the models created, 200 N vertical and 150 N oblique (45° angled buccopalatal direction) forces were implemented to the bilateral tooth regions 4-5-6 on the rigid titanium-supported fixed hybrid prosthesis made on these models. When the stress values in the models were investigated, the oblique forces had higher stress values than the vertical forces did. When the stresses created by oblique forces were assessed, the highest values were observed in the models created with short implants, and the lowest stress values were observed in the models made with 30° angle to mesial. When bone densities were assessed, more stress values were noted in models with D4 bone density. It has been shown that mesial tilted long implants placed in the posterior molar region, in addition to all four implant treatment concepts, create less stress against undesirable oblique forces compared with short implants.
The ultimate goal in implantology is to restore the whole tooth-gingival complex in a fashion that cannot be distinguished from the rest of the natural dentition. This study assesses the volumetric and clinical changes i...The ultimate goal in implantology is to restore the whole tooth-gingival complex in a fashion that cannot be distinguished from the rest of the natural dentition. This study assesses the volumetric and clinical changes in vestibular gingival soft tissues, crucial for satisfactory engraftment and esthetic results, upon treatment with laser-aided pouch roll augmentation in second-stage surgery for dental implant uncovering. Twelve patients with mild ridge deficiencies in 16 edentulous sites, including distal elements, were enrolled and reevaluated for up to 1 year. Digital impressions, taken with an intraoral laser scanner and software, were analyzed before (day 0) and after (month 12) treatment. The digital STL files were superimposed to assess volumetric and linear dimensional variations in selected peri-implant regions of interest by 3D analysis software. Clinical periodontal parameters (probing depth [PD], bleeding on probing [BoP], plaque index [PI]) and subjective patient-reported outcomes were also evaluated. In all patients, the applied technique induced a substantial increase in the volume of the vestibular peri-implant gingiva at 12-month follow-up (range, 24%-69%, mean 40.4%) with respect to day 0. The gingival mucosa appeared normal at both inspection and evaluation of the periodontal parameters (PD 2.7 ± 1 mm; BoP 0.11 ± 0.2 seconds; PI 0.19 ± 0). Patients' satisfaction with perceived pain/discomfort and esthetic outcome was high. These findings indicate that laser-aided pouch roll flap is a safe, patient-liked procedure whose long-term effectiveness has been objectively demonstrated by volumetric and clinical assessment.
When considering placing dental implants in atrophic edentulous sites, there may be inadequate site width and little or no vertical bone loss. Any of several surgical procedures can augment these sites. Extracortical aug...When considering placing dental implants in atrophic edentulous sites, there may be inadequate site width and little or no vertical bone loss. Any of several surgical procedures can augment these sites. Extracortical augmentation is done by applying graft material against the cortical bone. This technique expects progenitor cells to migrate outside the bony ridge's confines and form new bone. Another method entails ridge splitting and expansion to create space for osteogenesis and, when possible, implant placement. This may be a better method for horizontal ridge augmentation. The ridge is split, separating the facial and lingual cortices for a complete bone fracture. The patient's osseous cells can then migrate into the created space from the exposed medullary bone to form bone. The technique can be preferably performed flapless so the intact periosteum maintains a blood supply to ensure appropriate healing.
The objective of this paper was to assess the outcome of bone graft material at alveolar bone augmentation sites combined with dental implants in postmenopausal women with compromised bone health by evaluating cone beam...The objective of this paper was to assess the outcome of bone graft material at alveolar bone augmentation sites combined with dental implants in postmenopausal women with compromised bone health by evaluating cone beam computerized tomography (CBCT) scans at multiple time points.CBCT scans were analyzed on 55 postmenopausal women with compromised bone health status to determine the fate of alveolar bone augmentation. CBCT scans were taken immediately after surgery and 9 and 24 months postoperatively. The patient's medication regimens and durations were recorded, and the pixel intensity value (PIV) was measured and standardized using scoring criteria and visual assessment. Statistical analyses included 2-sample t tests for continuous variables and Fisher's exact tests for categorical variables.Among the normal patients, 73% received a grade 2 visual score, and 27% received a grade 1 visual score. After 24 months, 45% of patients received a grade 2 score, and 27% received a grade 3 score. In the osteoporotic group receiving medication, 77% of participants received a grade 1 visual score at the 9-month postoperative evaluation, while 23% received a grade 2 score. At the 24-month assessment, 55% of patients received a grade 1 score, 41% received a grade 2 score, and only 5% received a grade 3 score. Notably, although the graft material did not remodel into native bone, it was a scaffold for implants in controlled osteoporotic patients. The study's results show that the pixel intensity values of particulate graft materials are similar across the three different time points, suggesting that the graft material's pixel intensity value remains constant in postmenopausal women with osteoporosis. The study's limitations include a small sample size and a restricted 24-month follow-up period. This limited time frame may need to capture long-term changes or variations in graft materials adequately. Future research should include a larger sample size and have a longer follow-up duration to provide a more comprehensive understanding of the change in graft materials between patients with normal and compromised bone health.
Various factors influence marginal bone loss after implant placement. This study explored the association between marginal bone loss and posterior implants positioned at different bone levels. Computer records and radiog...Various factors influence marginal bone loss after implant placement. This study explored the association between marginal bone loss and posterior implants positioned at different bone levels. Computer records and radiographs of patients with at least 2 adjacent implants were retrieved. Cases were categorized into nonsplinted prosthesis and splinted prosthesis groups. Radiographic measurements were conducted at the time of abutment placement (T0), 1-3 years follow-up (T1), and the last visit (T2), measuring the vertical distance between adjacent implants. Multilevel linear regression models using generalized estimating equations were employed, with a significance level set at 5% (α = 0.05). Fifty-six patient records were included, comprising 120 implants: 84 nonsplinted (70%) and 36 splinted (30%). In the nonsplinted group, marginal bone loss progression significantly depended on crestal height differences. For the mesial sides of posterior implants, marginal bone loss measured 1.0 ± 0.6 mm from T0 to T1, 2.4 ± 1.1 mm from T1 to T2, and 3.4 ± 1.2 mm from T0 to T2. Similarly, the distal sides of the most anteriorly placed implant exhibited marginal bone loss of 1.0 ± 0.7 mm from T0 to T1, 2.4 ± 1.0 mm from T1 to T2, and 3.5 ± 1.2 mm from T0 to T2. Nonsplinted implants demonstrated a higher progression of marginal bone loss. This study suggests that nonsplinted implants may lead to a more pronounced progression of marginal bone loss, particularly concerning crestal height differences, underscoring the need for further research.
Reconstruction of maxillary defects can be carried out using a variety of treatment modalities. The choice of modality depends on numerous factors, including the size and extent of the defect, patient characteristics, an...Reconstruction of maxillary defects can be carried out using a variety of treatment modalities. The choice of modality depends on numerous factors, including the size and extent of the defect, patient characteristics, and existing comorbidities. One of the various options is reconstruction and rehabilitation using a fixed prosthesis supported over a zygomatic implant. In maxillectomy cases, a zygomatic implant can be used to improve the retention of the obturator prosthesis, as the loss of alveolar bone makes it impossible to use conventional endosseous implants. Although zygomatic implants are reported to have high success rates, they are not free of complication. We hereby present a rare complication associated with the placement of a zygomatic implant in a patient with COVID-19-associated mucormycosis who underwent operation. This rare complication has never been reported before. This case report also highlights on the management of complications involving displacement of a zygomatic implant in the infratemporal region.
The goal of this clinical report was to present an alternative to traditional flat bone reduction guides, using a custom-designed 3-dimensional (3D)-printed guide according to the future gingival margin of the planned de...The goal of this clinical report was to present an alternative to traditional flat bone reduction guides, using a custom-designed 3-dimensional (3D)-printed guide according to the future gingival margin of the planned dentition. A 61-year-old woman with concerns regarding her smile appearance was presented. The initial examination revealed excessive gingival show accompanied by excessive overjet. The dentition was in a failing situation. The proposed treatment plan, relying on the sufficient amount of bone and keratinized tissue, consisted of recontouring of the alveolar ridge and gingiva and placement of 6 implants and an FP-1 prosthesis after extraction of all remaining maxillary teeth. Digital smile design was completed, and a fully digitally guided surgery was planned. This consisted of using 3 surgical guides, starting with the fixation pin guide, continuing with the scalloped hard- and soft-tissue reduction guide, and finally the implant placement template. Following the surgery, the patient received a temporary restoration, and on the 4-month follow-up, a new polymethyl meta-acrylate temporary prosthesis was delivered. The patient's 7-month follow-up is presented in the article. The report of this triple-template guided surgery indicated that digital 3D planning is a considerably predictable tool to properly establish and evaluate future occlusal plane, smile line, and lip support. Scalloped guides seem to be an excellent alternative to conventional bone reduction guides since they require less bone removal and improve patient comfort during surgery.
Bone augmentation is often required before the installation of dental implants. Here, we report a case for a patient who previously received bone augmentation at the upper right jaw using a xenogenic graft, followed by s...Bone augmentation is often required before the installation of dental implants. Here, we report a case for a patient who previously received bone augmentation at the upper right jaw using a xenogenic graft, followed by successful implant installation. Seven years later, the patient presented with mucosal fenestration with bone exposure at the area and gave a history of a recent diagnosis of cutaneous lichen planus. Several attempts were made to manage the situation, and finally, we resorted to connective tissue graft placement at the site. A piece of bone was sent for histologic evaluation, where the results indicated the presence of un-resorbed graft material surrounded by inflammatory cells, with no evidence of bone formation in the area. The case presents histologic evidence for the lack of new bone formation using xenograft over the evaluation period. The case also shows lichen planus, a possible cause for oral complication for patients undergoing augmentation and implant installation.
The aim of this study was to evaluate the mechanical behavior of UCLA and Mini-conical abutments for implants with Tri-channel connections regarding torque loss and vertical misfit. Twenty 3-element metal-ceramic fixed p...The aim of this study was to evaluate the mechanical behavior of UCLA and Mini-conical abutments for implants with Tri-channel connections regarding torque loss and vertical misfit. Twenty 3-element metal-ceramic fixed partial dentures (FPD) supported by 2 implants were manufactured and divided into 2 groups (n = 10): UCLA (group 1) and Mini-conical Abutments (group 2). The evaluation of torque loss was carried out before and after mechanical cycling, while the vertical fit was evaluated throughout the different stages of manufacturing the prostheses, as well pre- and postcycling (300,000 cycles, 30 N). Statistical analyses of torque loss and vertical misfit were performed using the linear mixed effects model. Both groups showed torque loss after mechanical cycling (P < .05); however, there was no significant percentage differences between them (P = .795). Before cycling, the groups showed a significant difference in terms of vertical misfit values (P < .05); however, this difference was no long observed after cycling (P = .894). Both groups showed torque loss after the cycling test, with no significant difference (P > .05). There was no significant difference in vertical misfit after mechanical cycling; however, in group 1 (UCLA) there was accommodation of the implant-UCLA abutment interface, while group 2 (Mini-conical abutment) did not show changes in the interface with the implant after the test. Both groups behaved similarly regarding the torque loss of the prosthesis retention screws pre- and postmechanical cycling, with greater loss after the test.
Alveolar bone quality at the implantation site affects the initial stability of dental implant treatment. However, the relationship between bone quality and osseointegration has yet to be evaluated. Herein, we aimed to i...Alveolar bone quality at the implantation site affects the initial stability of dental implant treatment. However, the relationship between bone quality and osseointegration has yet to be evaluated. Herein, we aimed to investigate the effect of bone quality on dental implant stability in osseointegration formation changes. Patients underwent computed tomography imaging before dental implantation at the posterior. Hounsfield units were measured at the platform, middle, and tip sites. Implant stability was measured using resonance frequency analysis immediately and at 3 months postoperatively, in which the difference in implant stability quotients (ISQ) was defined as the change between primary and secondary fixation. In multiple regression analysis, the dependent variable was the change between the immediate and secondary fixations. We included 81 implants that conformed to the criteria. Primary fixation yielded the following results: R2 = 0.117, F = 2.529, and P = .047. The difference between the maxilla and mandible of the implantation site (P = .02) and the platform-site Hounsfield units (P = .019) were identified as significant factors. The following results were obtained regarding the change between the immediate and secondary fixation: R2 = 0.714, F = 40.964, and P < .001. The difference between diameter (P = .008) and the immediate ISQ (P < .001) were identified as significant factors. Overall, the bone quality of the implantation site affected initial fixation; however, it had limited effect on secondary fixation. Our findings clarified the period where bone quality affects dental implant treatment and is expected to advance dental implant treatment.
The stability of implant-abutment joint is fundamental for the long-term success of implant rehabilitation. The screw loosening, fracture, and head deformation are among the most common mechanical complications. Several...The stability of implant-abutment joint is fundamental for the long-term success of implant rehabilitation. The screw loosening, fracture, and head deformation are among the most common mechanical complications. Several surface treatments of titanium screws have been proposed to improve their resistance and stability. Diamond-like carbon (DLC) coating of the materials is widely used to increase their wear resistance and durability. The present study aimed to evaluate the effect of carbon fiber coating on the screw head on screw removal torque and screw head stripping. One hundred titanium implant screws were used, 50 without coating (Group 1) and 50 with DLC coating of the screw head (Group 2). Each screw was tightened with a torque of 25 Ncm and unscrewed 10 times. The removal torque was measured with a digital cap torque tester for each loosening. Optical 3d measurement of the screw head surface was performed by a fully automatic machine before and after multiple tightening to investigate surface modifications. The reverse torque values decreased with repeated tightening and loosening cycles in both groups without significant differences (P > .05). Optical measurements of surface dimensions revealed average changes of 0.0357 mm in Group 1 and 0.02312 mm in Group 2, which resulted to be statistically significant (P < .001). The DLC coating of the retention screw head can prevent its distortion and wear, especially after multiple tightening.
Ingestion or aspiration of dental implant screwdrivers or implant components is potentially life-threatening. There are no reports on the frequency at which dentists drop these devices within the mouth or which component...Ingestion or aspiration of dental implant screwdrivers or implant components is potentially life-threatening. There are no reports on the frequency at which dentists drop these devices within the mouth or which components are most problematic. There are few reports on what protective measures clinicians take, where risks exist, and how this problem is managed. A 9-part questionnaire was provided to dentists. Data collected included clinicians' roles, implant surgeons, restorative clinicians, or both-the frequency of dropping implant screwdrivers or components, items considered most problematic. Patient protection and management were also requested. Finally, questions related to how much of a problem clinicians considered this to be and if further solutions and a standardized management protocol should be developed. One hundred twelve dentists voluntarily completed the survey. Of the dentists, 54% restored, 37% restored and surgically placed, and 9% solely placed implants. Twenty-nine percent claimed never to drop components, with 56% dropping an instrument less than 10% of the time. Less than half would suggest patients seek medical advice if a screwdriver or component was accidentally dropped intraorally and was not recovered. Thirty percent never tied floss tethers to screwdrivers, and a similar percentage reported they only sometimes did so. Throat pack protection was reported 51% of the time. Ninety percent considered dropping components an issue, with screwdrivers most problematic. Aspiration or ingestion of implant screwdrivers and components is problematic, with dentists varying their use of protection devices. There is a need to standardize and implement patient protection procedures and management and develop methods to reduce the risk of these potentially life-threatening issues.
This case report of a 45-year-old patient at initial presentation shows an illustration of the limitations of periodontal maintenance therapy and subsequent implant prosthetic therapy. In close consultation with the pati...This case report of a 45-year-old patient at initial presentation shows an illustration of the limitations of periodontal maintenance therapy and subsequent implant prosthetic therapy. In close consultation with the patient, treatment strategies were adopted to maximize the preservation of prognostically questionable teeth. Eight years later, the patient had a highly atrophied maxilla that could be successfully restored with implants. This was achieved with 2 zygoma implants and 2 anterior conventional implants, which were immediately loaded according to the All-on-4 concept and immediately provided with a definitive prosthetic restoration. The case report demonstrates to the general practitioner that using zygoma implants in such constellations may offer a solution to achieve a fixed, rapid, and financially acceptable prosthetic rehabilitation.
The study is aimed to assess the effects of serum vitamin D levels and their relationship to early dental implant failures. A total of 174 implants in 109 patients were placed and serum vitamin D levels were noted on the...The study is aimed to assess the effects of serum vitamin D levels and their relationship to early dental implant failures. A total of 174 implants in 109 patients were placed and serum vitamin D levels were noted on the day of implant placement. Implants were followed up until restoration, approximately 3-6 months later, and any implant failure was reported based on 50% or more bone loss or implant mobility. Eight individuals had an implant fail early and their vitamin D levels had a mean of 42.54 ng/mL compared with the successful patients' levels of 31.92 ng/mL. Although not statistically significant, there was no correlation between patients' low serum vitamin D levels and early implant failure.
This study evaluated the clinical survival rates of 170 Morse taper implants through clinical and mechanical parameters in different therapeutic approaches such as single crowns, fixed partial prostheses, and fixed full-...This study evaluated the clinical survival rates of 170 Morse taper implants through clinical and mechanical parameters in different therapeutic approaches such as single crowns, fixed partial prostheses, and fixed full-arch prostheses. Patients referred to the Center on Education and Research on Dental Implants from May 2017 to July 2018 with the indication for dental implant therapy, aged >18 years, without periodontal disease, recent evidence of inflammatory activity or other oral disorders, current pregnancy, uncontrolled diabetes mellitus or heavy smoking habit were included in this study. After 12 weeks of healing since the implants were placed in the mandible and after 16 weeks following implants placed in the maxilla, patients returned to the Center for prosthetic rehabilitation. After implant therapy, all patients underwent periodical, clinical, and prosthetic examinations every 6 months. Prosthetic restorations involved 109 fixed reconstructions in function. Few prosthetic complications were reported (6.55%). Twenty implants were rehabilitated with cemented prostheses; from those, 1 crown suffered a loss in retention/decementation. Of the 148 implants rehabilitated with screwed-retained prostheses, 6.76% suffered prosthetic screw loosening. The cumulative implant survival rate was 98.2%. When peri-implant tissue health was evaluated, the keratinized mucosa band appeared related to peri-implant tissue stability. Thus, Morse taper implants represented a successful procedure for implant rehabilitation, with a high cumulative implant survival rate, low prevalence of biological and prosthetic complications, and good stability of peri-implant tissues over the assessed period.
A series of 50 cases involving reconstruction of the fully edentulous maxilla using sinus grafts, bone expansion, and classic crown and bridge to restore to normal contour, comfort, health, function, and esthetics is ret...A series of 50 cases involving reconstruction of the fully edentulous maxilla using sinus grafts, bone expansion, and classic crown and bridge to restore to normal contour, comfort, health, function, and esthetics is retrospectively analyzed using 25 years of follow-up data.