Biological Complications Research Articles

Retrospective cohort assessment of survival and complications of zygomatic implants in atrophic maxillae.

To report on zygomatic implant (ZI) survival rate and associated complications through a longitudinal retrospective cohort assessment. A total of 940 ZIs (rough: 781, machined: 159; immediate loading: 454, delayed loading: 486) and 451 standard implants (rough: 195, machined: 256; immediate loading: 58, delayed loading: 393) were placed in 302 adult patients with atrophic maxilla from December 1998 till September 2020. Following data collection reported complications were grouped based on their origin as infectious/ non-infectious biological and mechanical. Statistical analysis was performed to identify risk factors and preceding complications leading to implant loss (P < 0.05). The survival rate of ZI was found to be 89.9% and the average time between implant placement and an eventual loss was 4.8 years. The mean ZI follow-up period was 7.9 ± 4.9 years. Amongst the infectious biological complications, sinusitis was the most reported (n=138) occurring at a mean follow-up time-point of 4.5 years, whereas infraorbital nerve hypoesthesia occurred more frequently in the non-infectious biological category (n=8, meantime: 0.3 years). The prosthetic screw fracture was the most reported complication of mechanical origin (n=29, meantime: 4 years). Furthermore, sinusitis, standard implant loss, zygomatic/peri-zygomatic region infection, and oroantral communication were significantly associated with ZI loss. ZI placement offered a high survival rate for the rehabilitation of severely atrophied maxilla with most losses occurring within the first 5 years at follow-up. The most frequently observed complication was sinusitis which tends to develop several years following implant placement.

Impact of local predisposing/precipitating factors and systemic drivers on peri-implant diseases.

Strong evidence suggests the infectious nature of peri-implant diseases occurring in susceptible hosts. Epidemiological reports, though, indicate that peri-implantitis is a site-specific entity. Hence, the significance of local factors that may predispose/precipitate plaque accumulation and the impact of systemic drivers that alter the immune response are relevant in the prevention and management of peri-implant disorders. The purpose of the present review is to shed light on the significance of local and systemic factors on peri-implant diseases, making special emphasis on the associations with peri-implantitis. The biologic plausibility and supporting evidence aiming at providing a concluding remark were explored in the recent scientific literature for local predisposing/precipitating factors and systemic drivers related to peri-implant diseases. Local predisposing factors such as soft tissue characteristics, implant position and prosthetic design proved being strongly associated with the occurrence of peri-implant diseases. Hard tissue characteristics, however, failed to demonstrate having a direct association with peri-implant diseases. Robust data points toward the strong link between residual sub-mucosal cement and peri-implant diseases, while limited data suggests the impact of residual sub-mucosal floss and peri-implantitis. Systemic drivers/habits such as hyperglycemia and smoking showed a strong negative impact on peri-implantitis. However, there is insufficient evidence to claim for any link between metabolic syndrome, atherosclerotic cardiovascular disease, and obesity and peri-implant diseases. Local predisposing/precipitating factors and systemic drivers may increase the risk of peri-implant diseases. Therefore, comprehensive anamnesis of the patients, educational/motivational programs and exhaustive prosthetically-driven treatment planning must be fostered aiming at reducing the rate of biological complications in implant dentistry.

Clinical Outcome of Immediate Loading UV-Photofunctionalized Implants in Patients with Completely Edentulous Mandible, Placed with Guided Surgery.

The purpose of this study was to evaluate clinical results of immediate loading UV-photofunctionalized dental implants placed using guided surgery in patients with completely edentulous mandible. In this study, 58 fully edentulous patients were treated with immediate loading implant-supported mandibular prostheses. All patients underwent a thorough clinical examination according to the generally accepted scheme; qualitative and quantitative parameters of the jaw bones patients were diagnosed with cone beam computerized tomography (CBCT). Surgical templates modeled in the 3 Shape software were made from biocompatible polymeric materials and provided with depth-calibrated drill sleeves for preparing osteotomies using a 3D printer (Stratasys). Before short implant placement, ultraviolet functionalization of implant surfaces was performed by UV Activator YWJ-QSY001 (Foshan, Wenjian Medikal Enstriman) in the device for 20s. After flapless surgery, implant sockets were prepared with guided surgery and implants were placed through the sleeves of the surgical template tightening torque of 35-45 Ncm. An implant-supported temporary prosthesis made of acrylic resin was installed 6h after implantation. Final dental prosthetics was performed 2months after implant placement.The patients had 128 short (length 5-6mm, diameters 4,5-5mm) and 256 implants with length greater than 10mm in bone segments with sufficient bone parameters. The following parameters were assessed: implant success, prosthetics survival and changes in peri-implant marginal bone loss(MBL). During a clinical examination, no serious biological or prosthetic complications have been reported. The esthetic result evaluated from patients was excellent. The mean ISQ of short implants was 69.2 ± 8 for primary stability at implant placement and 73.6 ± 4 ISQ after 3months. The mean of implants with length greater than 10mm was 71,2ISQ at implant placement, respectively, and 75,6 ISQ after 3months. After 3months of prosthetic loading for short implants marginal bone loss (MBL) 0.74mm, after 1year of MBL 11.21mm, after 5years of MBL 1,37mm, for implants with length greater than 10mm after 3months of MBL 0.72mm, after 1year of MBL 1.19mm and after 5years of MBL 1.35. There was no statistically significant difference in clinical indices between short and standard implants. After 5years of follow-up, stable levels of bone tissue around the implants and healthy tissues around the implants were recorded, and postoperative occlusal function was favorable. The success rates of the short implants in maxilla were 95.5%, and the success rates of the short implants in mandible were 98.7%. The success rates of the implants with length greater than 10mm in maxilla were 97.8%, and the success rates of the implants with length greater than 10mm in mandible were 98.8%. Computer-guided implant surgery and immediate loading of UV-photofunctionalized implants in patients with completely edentulous mandible are a predictable and effective method with a minimum rehabilitation period.

Is the Diagnosis of Generalized Stage IV (Severe) Periodontitis Compatible with the Survival of Extended Stabilizing Prosthetic Restorations? A Medium-Term Retrospective Study.

The aim of the study was to identify the most relevant patient-related factors directly involved (alone or in combinations) in the long-term survival and functionality of the abutment teeth of extensive stabilizing bridges and removable prosthesis, in patients treated for Stage IV periodontitis, adhering to SPT over a period of at least 5 years. Seventy-six patients treated between 2000-2022, rehabilitated with FDPs and RDPs, adhering to SPT for at least 5 years were included. Patient-related factors influencing retention of RDPs and FDP, survival rates in regular (RCs) and irregular compliers (ICs), and incidence of biological and technical complications were assessed. During a follow-up of 69 months, from 57 patients with FDPs and 19 patients with RDPs, 39 (51.32%) were ICs, while 37 (48.68%) were RCs. An overall statistically significant association (p = 0.04) was identified between biological complications and the type of prostheses. The RDP patients had more complications than FDP patients. In 5.26% of the RDP patients, root caries were identified, and 10.53% were diagnosed with a periapical (endodontic) lesion, while 3.51% of the FDPS patients presented root caries. In five (6.57%) cases, abutment loss resulted in the loss of the prosthesis. Statistically significant correlations were observed between systemic diseases and tooth loss, and between type of tooth lost and the reason for tooth loss, irrespective of the type of prosthesis. A total of 66.67% of the lost incisors, 85.71% of the lost premolars, and 88.89% of the lost molars occurred due to periodontal causes. Furthermore, 93% of the FDPs and RDPs were still in place and in function.

Immediate Loading of Fixed Prostheses in Fully Edentulous Jaws: A 7-Year Follow-Up from a Single-Cohort Retrospective Study

The aim of this retrospective single-cohort study was to evaluate the clinical outcome of four-to-five implants immediately restored with metal-resin screw-retained cross-arch fixed prostheses in edentulous jaws 10 years after loading. One-hundred-and-four consecutive patients received four to five implants placed with a torque superior 35 Ncm. One-hundred-and-twenty-seven metal-resin screw-retained fixed prostheses (59 mandibular and 68 maxillary) were to be delivered within 3 days. Outcome measures, evaluated by the treating clinician, were: prosthesis and implant failures, prosthetic modifications, peri-implant mucositis, and biological and prosthetic complications. A total of 549 implants were placed. Twenty-one implants failed in 14 patients and 102 prostheses were remade, at least once, in 81 patients: 2 due to implant failures and 33 because of fractures of the prostheses. In particular, 25 original metal-resin prostheses had to be remade because of fractures versus only eight of the replacement monolithic metal-resin prostheses. All patients were wearing fixed prostheses at the end of the follow-up. Thirty-six biological complications occurred in 22 patients. Eighty-six prosthetic complications occurred in 42 patients. In conclusion, immediately loaded cross-arch prostheses supported by four-to-five immediately placed implants are a viable therapeutic option if robust prostheses are made.

Clinical performance of lithium disilicate and zirconia CAD/CAM crowns using digital impressions: A systematic review.

The purpose of this systematic review was to compare the clinical performance of lithium disilicate (LDS) and zirconia (Z) single crowns manufactured by computer-aided design/computer-aided manufacturing (CAD/CAM) systems using intraoral optical scanners (IOS). An electronic search for articles published between January 2012 and January 2022 in the English language was performed with the Medline/Pubmed database under the guidelines of Preferred Reporting Items for Systemic Reviews and Meta-analysis (PRISMA). The specific search terms used were "zirconia", "lithium disilicate", "CAD/CAM", "intraoral optical scanner", and "survival". The initial electronic search resulted in 278 articles. Most of the resulting articles were excluded, six clinical studies addressing the clinical outcomes of Z and LDS crowns fitted the inclusion criteria and were selected for review. Of these six studies, three were randomised controlled trials, two were retrospective studies, and one was a prospective study. To quantify the clinical performance of the crowns several parameters were recorded, including fractures, endodontic complications, periodontal complications, technical complications, aesthetic complications, and biological complications. It was noted that the most common technical complication of Z and LDS crowns was chipping at a rate of 1.4% and 5% respectively. Regarding Z crowns, aesthetic concerns were the most frequently observed complication. The outcomes of this systematic review indicate that Z and LDS crowns display a similar incidence of periodontal and endodontic complications when compared to metal-ceramic crowns, suggesting that these all-ceramic materials are viable alternatives. The incidence of chipping was higher in LDS crowns compared to other materials, while Z crowns were inferior in terms of aesthetics.

Correlational study of technical, biological and esthetic complications and level of satisfaction in treatments performed in the Department of Prosthesis of Crowns and Bridges II of the Faculty of Dentistry of the National University of Asuncion

El objetivofue determinar la asociación correlacional que pudiera presentarse entre las complicaciones técnicas, biológicas y estéticas y el nivel de satisfacción de los tratamientos realizados en la Cátedra de Prótesis de Coronas y Puentes II de la Facultad de Odontología de la UNA en el 2019. Este fue un estudio observacional descriptivo, analítico, de corte transverso. Se incluyeron pacientes que recibieron tratamientos del 2016 al 2018. Acudieron 59 pacientes para la evaluación clínica y aplicación del cuestionario. Se analizaron los datos según número de tratamientos encontrados en cada sujeto, por lo que se calcularon los resultados según 119 tratamientos. Las complicaciones biológicas pulpares fueron la sensibilidad o molestia al frio o al calor en los pilares en un 20.1%. Se encontró asociación muy significativa de las complicaciones biológicas pulpares (p&gt;001) con estado civil, complicaciones biológicas periodontales, complicaciones estéticas cervicales. Las complicaciones biológicas periodontales fueron en mayor frecuencia la gingivitis alrededor de la restauración en un 40,4%. El nivel de satisfacción con el tratamiento recibido se presentó favorable en un 89,1% y asociación muy significativa (p&gt;001) con grado de instrucción y significativa (p&gt;005) con estado civil.Se encontró asociación muy significativa de las complicaciones estéticas cervicales, las complicaciones estéticas de forma y significativa de las complicaciones biológicas periodontales con el nivel de satisfacción

Modified Periosteal Inhibition (MPI) Technique for Extraction Sockets: A Case Series Report

Several Alveolar Ridge Preservation (ARP) procedures have been proposed over the years. The purpose of this study was to describe the new Modified Periosteal Inhibition (MPI) technique for ARP. Seven patients were enrolled (age range: 28–72 years old; 5 males, 2 females). In total, nine hopeless teeth were treated. Following the elevation of a full-thickness flap, atraumatic tooth extraction was conducted, preserving the buccal bone of the alveolar socket. OsteoBiol® Lamina Soft (Tecnoss®, Giaveno, Italy), 0.5 mm thick, was suitably shaped (8–10 mm in height, extending from the mesial and to the distal corners of the socket). The lamina was gently positioned between the buccal periosteum and the buccal bone plate. Tisseel® (Baxter Healthcare Corporation, Deerfield, IL, USA) was applied to seal the cortical membrane. The flaps were sutured with PTFE 4-0 (Omnia, Fidenza, Italy). Postoperative instructions were provided. Patients were strictly monitored during the follow-up. No early or late biological complications were experienced. Cone Beam Computed Tomography (CBCT) exams were performed at baseline and 4 months later. The thickness of the buccal cortical bone at baseline was 1.18 ± 0.57 mm. The pre-operative and post-operative ridge widths were 10.74 ± 1.54 mm and 11.16 ± 1.57 mm, respectively. A horizontal ridge increase of 0.41 ± 0.21 mm was observed during the healing period. At 4 months of healing, the bone volume was adequate for implant placement and no additional bone regeneration procedures were required. MPI technique was effective in preventing the horizontal contraction of the post-extraction socket. Further studies will be needed in the future to confirm our positive results.

Secondary caries in fixed dental prostheses: Long-term clinical evaluation.

Even with excellent fixed dental prostheses (FDPs), there will be a substantial risk of biological complications, such as caries, if proper oral hygiene is not maintained. This study aimed to evaluate the risks of developing secondary caries withFDPs in relation to the patient oral hygiene status. Clinical and radiographic examinations were performed for patients to collect data related to their FDPcomplications and oral hygiene status. The main clinical parameter analyzed was secondary caries. Complications such as a fracture, debonding, or the need for endodontic therapy were also analyzed. The interval survival rateand the cumulative survival rateof FDPs from the time of treatment to the time of follow-up were analyzed. A total of 423 patients (with a total of 1116 FDPs) were examined in this study, with a mean age of 43.7 years and a mean follow-up time of 7 years. Regarding complications, secondary caries was detected in 94 FDPs (8.4%), fracture (or chipping) in 85 (7.6%) cases, need for endodontic treatment in 42 cases (3.7%), and debonding in four(0.3%) cases. Secondary caries was found in nineout of 219 FDPs (4%) in patients with good oral hygiene, 35 out of 634 FDPs (5.5%) in patients with fair oral hygiene, and 50 out of 272 FDPs (18.4%) in patients with poor oral hygiene (p ≤ .001). Good oral hygiene has a great influence on reducing the risk of secondary caries in patients with FDPs. The occurrence of secondary caries is a common complication in patients with poor oral hygiene.

Prevention of soft and hard tissue injuries from implant attachments by using an attachment retained soft-hard tissue guard

Dental attachments, including dental implant attachments, when not in use can cause biological complications intraorally like soreness of lips, the floor of the mouth, tongue, or cheeks. The article describes an appliance designed for patients experiencing these complications. The described soft-hard tissue guard is newly designed and to be worn by the patient when attachments are not in use for retaining a prosthesis. The aim of this article is to describe the process of fabrication, advantages, disadvantages, and requirements of an attachment retained soft-hard tissue guard by means of a case report.

Occlusion as a predisposing factor for peri-implant disease: A review article.

The restoration of dental implants presents a unique challenge due to the intrinsic biomechanical differences between osseointegrated implants and natural teeth, and their subsequent responses to occlusal loading. However, controversy exists regarding the role that occlusion plays in the physiology of the peri-implant complex. To provide an overview of the scientific literature regarding occlusion as it relates to implant dentistry and peri-implant disease. This article presents a narrative review on occlusal loading and its potential effects on the peri-implant complex, as well as some generally accepted guidelines for occlusion in implant dentistry. Although there is strong evidence linking occlusal factors to mechanical complications of dental implants, the same cannot be said regarding biological complications. There is no clear scientific evidence on the relationship between occlusal overload and peri-implant disease. However, occlusal overload may be an accelerating factor for peri-implant disease in the presence of inflammation. As the biomechanical properties of dental implants differ from that of the natural dentition, modifications to classic concepts of occlusion may be necessary when dental implants are involved. Thus, clinical recommendations are proposed which function to minimize unfavorable occlusal forces on implant restorations and reduce the associated biological and mechanical complications.

Survival and complications of zygomatic implants compared to conventional implants reported in longitudinal studies with a follow-up period of at least 5 years: A systematic review and meta-analysis.

Zygomatic implants (ZI) have been frequently indicated to rehabilitate patients with extensive atrophies in alternatives to major bone reconstructions. It can be installed inside the maxillary sinus, called instrasinus zygomatic implant (IZI) or outside the maxillary sinus (EZI), depending on the surgery technique. To evaluate the survival and complication rates of ZI in longitudinal studies when compared with conventional implants (CI). An electronic search was performed in five databases and in Gray literature for articles published until April, 2022. The eligibility criteria comprised observational cohort studies (prospective or retrospective) and randomized clinical trials (RCTs) with at least 5 years of follow-up, reporting survival rate of ZI versus CI. A meta-analysis was conduct with 18 studies. A total of 5434 implants (2972 ZI and 2462 CI) were analyzed in 1709 patients. The mean survival rate was 96.5% ± 5.02 and 95.8% ± 6.36 for ZI and CI, respectively (mean follow-up time of 78 months). There were observed no statistically significant between ZI and CI in prospective studies (risk ratio [RR] of 1.21; 95% confidence intervals [CIs]: 0.28 to 5.28; chi-squared [Chi2 ]=11.37; I2 =56%; degrees of freedom [df]=5; z-score=0.25; P=0.80), retrospective studies IZI (RR of 1.29; 95% CIs: 0.52 to 3.23; Chi2 =4.07; I2 =2%; df=4; z-score=0.55; P=0.58) and retrospective studies EZI (RR of 0.72; 95% CIs: 0.31 to 1.66; Chi2 =1.99; I2 =0%; df=3; z-score=0.78; P=0.44). The biological complications most related to ZI was sinusitis, followed by infection and oroantral communication. ZI have a high long-term survival rate (96.5% with a mean of 91.5months of follow-up), showing no significant difference when compared with CI. The most prevalent biological complication is sinusitis, being most commonly to the IZI technique. This systematic review (SR) was registered in INPLASY under number INPLASY202280025.

Custom-made additively manufactured subperiosteal implant.

Subperiosteal implants were introduced in the last century. Poor clinical results led those implants to be progressively abandoned. Recently, several Authors suggested a revival of subperiosteal implants as an alternative to regenerative procedures. The purpose of this study was to describe the clinical application of custom-made additively manufactured subperiosteal implant for fixed prosthetic rehabilitation of edentulous maxilla. Plaster models of the upper and the lower arch were scanned, as well as the mock-up. Digital Imaging and Communications in Medicine data obtained from cone beam computed tomography were processed through the thresholding procedure. The design of the subperiosteal implant was drawn on the stereolithographic model and scanned. Once the digital project of the subperiosteal implant was completed, it was sent to additive manufacturing. After the surgery, the patient was strictly monitored for up to 2 years. The outcomes were assessed based on the incurrence of biological and mechanical complications, postoperative complications, and implant survival. The patient did not suffer from postoperative complications. Neither biological nor mechanical complications occurred during the follow-up period. At the end of the study, the implant was still in function. Custom-made subperiosteal implants could be considered as an alternative to regenerative procedures for the rehabilitation of severe bone atrophy. Further studies are needed in the future to confirm the positive outcome.

Guided implant surgery with R2Gate®: A multicenter retrospective clinical study with 1 year of follow-up

PurposeTo present the results obtained with a novel sleeveless and keyless guided implant surgery system. MethodsInclusion criteria for this multicenter clinical retrospective study were fully or partially edentulous patients who had been treated with a sleeveless and keyless guided implant surgery system (R2Gate®, Megagen), and who had been rehabilitated with fixed restorations, with a minimum follow-up of 1 year. All surgeries and prosthetic procedures were conducted following the same protocol, and data were obtained from the patients’ medical records. The outcomes were the fit and stability of the surgical guide, any intra-operative and immediate post-operative complications, any biologic and prosthetic complications that occurred during the 1-year follow-up period, implant survival, and prosthetic success. ResultsSixty patients were selected for the installation of 124 implants, through a guided procedure: 66 sleeveless, keyless surgical guides were manufactured. The incidence of immediate intra-operative (lack of space: 12.1%; lack of implant stability 2.6%) and immediate post-operative (pain and discomfort: 6.6%; mild swelling 3.3%) complications was low. In total, 112/124 implants (90.3%) were successfully placed with a guided procedure, in 52 patients; among them, 82 (73.2%) were placed with a flapless procedure. Thirty fixtures supported single crowns (SCs), 42 fixed partial dentures (FPDs) and 52 full-arch (FA) restorations. Sixty-two fixed prosthetic restorations (30 SCs, 22 FPDs and 10 FAs) were delivered; among these restorations, 15 (24.1%) were subjected to immediate functional loading. All implants (100%) survived. Two implants had peri‑implant mucositis (1.6%), two SCs had abutment screw loosenings (1.6%), two FAs and one FPD had ceramic chipping/fracture (2.4%), for an overall prosthetic success amounting to 88.7%. ConclusionsWithin the limits of this study, this novel guided surgery system appeared to be clinically reliable; further studies are needed to confirm these results. Statement of Clinical RelevanceThe use of sleveless and keyless surgical guides can be clinically reliable and may be represent a valid option for the surgeon.

Clinical evaluation of narrow-diameter implants versus standard-diameter implants with lateral bone augmentation in posterior jaws: Three-year results of a randomized controlled trial.

The aim of this study was to compare the 3-year clinical outcomes of narrow-diameter implants (NDI) with standard-diameter implants (SDI) in conjunction with lateral bone augmentation in atrophic posterior jaws. Fifty patients were included and randomly assigned into two groups: Patients in Group 1 received NDI (Ø3.5 mm); patients in Group 2 received SDI (Ø4.3 mm) with simultaneous lateral bone augmentation. Implant survival rates, complications, crestal bone loss, peri-implant conditions, treatment cost, and patient satisfaction were compared. Three patients dropped out the follow-up. No implant loss was observed. The difference in technical complication rates between the two groups was 3.8% (95% CI: -13.7% to 21.3%). No significant differences in crestal bone loss were found between two groups at 3-year follow-up (0.55 ± 0.76 vs 0.41 ± 0.41 mm, p=.429). A total of 20.8% (5/24) of NDI were diagnosed with mucositis and 8.3% (2/24) with peri-implantitis. A total of 17.4% (4/23) of SDI showed mucositis and (1/23) 4.3% showed peri-implantitis. The total cumulative cost of treatment per patient in Group 1 (2849.6 USD, 95% CI: 2726.8-2972.4) was significantly lower than that in Group 2 (3581.4 USD, 95% CI, 3460.9-3701.9) over the 3-year follow-up (p < .01). The patient satisfaction rating of operation was significantly higher in Group 1 (85.42 ± 7.41 vs 80.48 ± 7.95, p=.033). NDI yielded favorable implant survival, acceptable technical and biological complications, and high patient satisfaction supporting single crowns in the atrophic posterior region after 3-year follow-up. NDI might be a reasonable alternative in horizontally deficient posterior jaws. Clinicaltrials.gov identifier: ChiCTR1800020426.

Clinical outcomes of single crown and 3-unit bi-layered zirconia-based fixed dental prostheses: An upto 6- year retrospective clinical study: Clinical outcomes of zirconia FDPs

ObjectivesThe aim of this retrospective clinical study was to evaluate the survival and the occurrence of technical and biological complications in bi-layered zirconia-based (Zi) single crown and 3-unit fixed dental prostheses (FDPs). Also, the study aimed to analyze the effects of tooth vitality (vital versus non-vital), abutment location (anterior versus posterior), and luting cement (self-adhesive resin versus resin-reinforced glass ionomer) on clinical outcomes. MethodsA total of 147 prostheses (in 94 patients) placed by undergraduate dental students in a university dental center during the period 2015–2021 were examined clinically using modified United States Public Health Service (USPHS) and California Dental Association (CDA) criteria. The mean duration of follow-up was 37 months (range, 6 - 63 months) for the single crowns (n = 77) and 25 months (range, 6 - 68 months) for the 3-unit FDPs (n = 70). Data were descriptively analyzed to determine the types and rates of complications based on USPHS and CDA criteria. The Kaplan-Meier survival estimation method was used to determine the cumulative survival and success rates of the prostheses (α=0.05). Differences in clinical outcomes (survival or failure) according to tooth vitality, luting cement, and location were statistically analyzed using cross-tabulations and Х2 test (α=0.05). ResultsThe Kaplan-Meier cumulative survival rate was estimated as 96% for the Zi 3-unit FDPs after 5.5 years, and 90% for the Zi single crowns after 4.8 years. The 5-year estimated success rate was 68% for both 3-unit FDPs and single crowns. Seven (9.1%) 77Zi single crowns and 70 2 (2.9%) Zi 3-unit FDPs were recorded as failures with occlusal roughness being the most commonly-observed complication (crowns: 4 [5.6%]; 3-unit FDPs: 8 [11.4%]). In terms of clinical outcomes, statistically significant differences were found between all included vital and non-vital teeth (p = .006), and cement types (p = .028). Taking single crowns alone, significant differences in clinical outcomes according to tooth vitality were noted (p = .036), but not for PFDPs. The location of the prostheses did not produce any significant differences in the clinical outcomes, for both prostheses types independently or combined (p > .05). ConclusionsThe estimated cumulative survival rates in this study for single crowns and 3-unit Zi FDPs concurred with the ranges reported in systematic reviews. Zi-based prostheses on vital teeth produced better clinical outcomes than those placed on non-vital teeth, and type of luting cement influenced the final clinical outcome. Clinical significanceZi crowns and 3-unit PFDPs fabricated using the specific CAD-CAM system used in the controlled environment of this study showed good clinical performance with minimal veneer porcelain chipping. Root canal treated teeth seem to be at higher risk for failure of Zi prostheses compared with vital teeth.

Immediate flapless full-arch rehabilitation of edentulous jaws on 4 or 6 implants according to the prosthetic-driven planning and guided implant surgery: A retrospective study on clinical and radiographic outcomes up to 10 years of follow-up.

to retrospectively evaluate clinical and radiographic outcomes of immediate, flapless full-arch prostheses, supported by 4/6 implants according to prosthetic-driven planning and guided surgery. The study involved 28 edentulous patients (20 female/8 males; average age 67.75 ± 8.627 years), 32 prostheses (17 all-on-4/15 all-on-6) and 164 implants. The Implants survival, prostheses success/survival, peri-implant marginal bone loss, incidence of biological and prosthetic complications were evaluated. Multiple linear regression analysis was performed to analyze the influence of implant and patient characteristics on marginal bone loss. Cumulative implant survival rate was 89.7% for all-on-four (seven failures) and 99.0% for all-on-six (one failure) after a mean follow-up of 6.46 ± 2.236 years (range 1-10 years). Cumulative prosthesis success rate was 51.5% (58.8% for all-on-four/ 43.8% for all-on-six). Prosthesis survival rate was 88.2% for all-on-four. No failure was registered in all-on-six. Mean value of marginal bone loss was 1.38 ± 0.1.28 mm at 5-year and 2.09 ± 0.56 mm at 10-year follow-up. No difference was found in the mean value of marginal bone resorption between all-on-four (1.56 ± 1.61 mm) and all-on-six (1.20 ± 0.85 mm) (p= 0.104) and between tilted (1.22 ± 1.29 mm) and axial implants (1.44 ± 1.27 mm) (p= 0.385) after 5-year follow-up. The incidence of biological complications was 1.0% in all-on-six (one mucositis) and 10.3% in all-on-four (two peri-implantitis). Prosthetic complications affected teeth of final rehabilitations with 3 detachments, 10 chippings or fractures, and 3 severe occlusal wears. Based on the results and within the limitations of the present study, the implant-supported hybrid prosthesis according to prosthetic-driven planning and guided surgery showed to be an efficient, safe, and effective approach to rehabilitate edentulous jaws.

Accuracy of the landing of the original and non-original supraconstructions on implants

BACKGROUND: An integral part of modern orthopedic dentistry is the rehabilitation of patients with partial or completely missing teeth using intraosseous implant prosthetics. Despite the high success rate of implant integration, practicing dentists continue to encounter biological and technical complications during prosthetic treatment. One of the reasons for the resulting complications is inaccuracies in the design of orthopedic components. Since today the Russian dental market offers a wide range of suprastructures from different manufacturers and price categories, there is a need to compare the accuracy of their designs.&#x0D; AIM: To identify the difference between the accuracy of fit of original and non-original suprastructures presented in the Russian dental materials market by studying microgaps between these components and original Straumann implants.&#x0D; MATERIAL AND METHODS: Seven bone-level implants and six tissue-level Straumann implants were used. The original Straumann titanium bone-level and tissue-level bases were used as control superstructures. The following non-original components were used as test specimens: cast cobaltchromium bone and tissue-level bases from GeoMedi, plastic burnout bone-level abutments from NT-trading, and non-original titanium bone- and tissue-level abutments from GeoMedi, Zirkonzahn, and NT-trading. Cobalt-chromium abutments for tissue-level to a soft state were obtained from GeoMedi. Cobaltchromium specimens, namely, cast-to-fabricate and pre-smooth abutments from GeoMedi and a plastic burnout abutment from NT-trading, underwent a full technical cycle of metal-ceramic crown fabrication. All specimens were pressed in epoxy using a SimpliMet 1000 automatic hot press. Specimens were ground using a Buehler Beta-1 grinding and polishing machine with an automatic Vector attachment. Grinding was conducted layer by layer in three steps with a step of 1 mm. The contact area was examined with a Tescan Mira LMU scanning electron microscope.&#x0D; RESULTS: Segments between the implant and abutment and between the abutment and screw were considered in calculating the study results. Using a scanning electron microscope (Tescan Mira LMU), the length of the gap sections not exceeding 1 m and the length of each gap section exceeding 1 m were measured on each segment. For each gap, the area percentage was calculated, with the gap width not exceeding 1 m.&#x0D; CONCLUSION: For Straumann bone- and tissue-level implants, the original Straumann titanium bases had the highest fit accuracy, but for Straumann bone-level implants, the non-original titanium abutments from GeoMedi and Zirkonzahn also had a similar fit. The fit of the non-original cobaltchromium bases from GeoMedi and the burnout plastic abutment from NT-trading did not meet the criteria for an accurate fit of the superstructures.

Piège diagnostique : neurotoxicité au lithium avec lithémie normale

We describe here the case of a 54-year-old bipolar woman, followed in psychiatry and treated with lithium and a selective serotonin reuptake inhibitor (escitalopram) and lamotrigine, presenting a lithium poisoning with an altered state of consciousness caused by a supposed mismanagement of her treatment. Lithium poisoning was suggested based on neurological clinical features, but the blood test brought out a lithium concentration within the therapeutic values at 1,2 mmol/L (N: 0,6–1,2 mmol/L). The classic biological complications related to lithium poisoning (hypercalcemia, diabetes insipidus) confirmed the diagnosis. The patient has been transferred to our nephrology department where she got two hemodialysis sessions conducting to clinical and biological improvement, confirming the diagnosis of lithium poisoning despite the normal blood levels. Later, she was transferred to the psychiatry department for follow-up and for treatment adjustment.

Intraorally welded wing abutments supporting full-arch prostheses: A retrospective clinical study.

Delayed loading in the rehabilitation of edentulous patients with an implant-supported prosthesis implies a longer treatment time. It requires additional surgery to uncover the submerged implants, and this may increase patients' discomfort and morbidity. The immediate loading-based technique described in this article involves creating a metal framework by intraorally welding the implants pair by pair, using specific wing abutments. The aim of the study was to investigate the implant-prosthetic success and complication rates of this technique when used to rehabilitate totally edentulous patients. The clinical records of totally edentulous patients were retrospectively evaluated. The prosthetic success rate as well as technical and biological complications were analyzed. Furthermore, the implant survival and success rates were assessed by measuring marginal bone loss (MBL) at the implant, prosthesis and patient levels. The records of 37 patients (284 implants and 43 prostheses) were included in the study. At the last follow-up (45.5 ±33.6 months), the prosthetic success rate was 100%. Mucositis affected 4 implants (1.4%), while peri-implantitis affected 4 implants (1.4%). Meanwhile, 7 implants (2.5%) showed a lack of early osseointegration. According to the criteria of Albrektsson et al., 271 implants (95.4%) were successful. The average MBL at the implant, prosthesis and patient levels was 0.26 ±0.42 mm, 0.26 ±0.19 mm and 0.26 ±0.18 mm, respectively. The technique described in this article seems to be a viable approach to the rehabilitation of totally edentulous patients through immediate loading. However, these results should be confirmed by appropriately designed prospective and comparative clinical studies.