Biological Complications Research Articles

Monolithic Hybrid Abutment Crowns (Screw-Retained) Versus Monolithic Hybrid Abutments With Monolithic Crowns (Adhesively Cemented): Three-Year Data of a Prospective Clinical Split-Mouth Study.

This study compares the restoration of single-tooth implants with screw-retained lithium-disilicate hybrid-abutment crowns and single-tooth lithium-disilicate crowns adhesively bonded to hybrid abutments with regard to objective clinical and subjective patient-specific evaluation criteria over a time of observation of 3 years. Two bone-level implants were placed in contralateral sides of the same jaw in 10 patients, each with two single-tooth gaps. After osseointegration, implants were uncovered and an impression was taken. In accordance with the split-mouth design, one implant in each patient was restored with a screw-retained hybrid abutment crown and the other implant with a hybrid abutment and an adhesively bonded single-tooth crown. The restorations were randomly allocated to the implants. Prefabricated titanium bases were used. The ceramic abutments and restorations were fabricated monolithically with pressed lithium-disilicate ceramic. An objective evaluation (survival, technical, or biological complications, FIPS) by the practitioner and a subjective evaluation (satisfaction, OHIP) by the patient were carried out after 3, 6, 12, 24, and 36 months after restoration placement. Both restoration types showed a survival rate of 100% after 3 years of observation. No technical or biological complications occurred. No significant difference was observed between the two types of restoration neither for objective (survival, technical or biological complications, FIPS) nor subjective (satisfaction, OHIP) evaluation criteria (p > 0.05). No statistically significant differences were observed between screw-retained and cemented pressed lithium-disilicate restorations on bone-level implants for both objective and subjective evaluation criteria, respectively. Monolithic hybrid-abutment crowns (screw-retained) and monolithic hybrid abutments with single-tooth crowns (cemented) made of pressed lithium disilicate can be used to successfully restore single implants.

Survey on Patient Perception of At-Home Bacterial Biofilm Control in Relation to Peri-Implant Soft Tissue Health.

Bacterial biofilm control around dental implants is critical for the health of the peri-implant soft tissue and longevity of dental implants. The patient's role in regular biofilm removal around dental implants is just as important as that of the dental hygienist. The purpose of this study is to identify the relationship between at-home dental implant care and patients' perceptions of peri-implant soft tissue health. A 15-item paper survey was distributed to adult patients undergoing professional dental hygiene maintenance at a specialty dental practice within a 3-month period and had at least one dental implant. Survey items included participant demographics, patient-reported adjunctive aids for dental implants and patient perceptions of dental implant oral hygiene practices and peri-implant soft tissue health. There was a statistical difference between time spent cleaning dental implants and peri-implant soft tissue health. An association was found between patients who reported spending more time cleaning their dental implants and less bleeding (p = 0.046/54%), gingival inflammation (p = 0.026/58%) and gingival tissue redness (p = 0.036/53%). Additionally, patients who more frequently underwent professional dental hygiene maintenance perceived less gingival inflammation (p = 0.001/66%). To promote peri-implant soft tissue health and reduce oral biological complications, best practice guidelines should be implemented, including optimal at-home dental implant care and regular professional dental hygiene maintenance.

Dental Implant Identification Methods

Dental implants are a well-accepted prosthetic alternative for missing teeth. After implant restoration, they will need maintenance in due course of time due to biological and mechanical complications, during which information about the implant system is required. Until today there is no well-established method for implant identification and conventional tools such as interpretation from radiographs need time and effort. Researchers have proposed several methods for implant identification and the review focuses on a comprehensive discussion of the proposed methods. For this review, comprehensive data from databases, including PubMed, Scopus, Web of Science, Cochrane, and Google Scholar, was thoroughly examined ensuring the most up-to-date and relevant information regarding implant identification. The proposed methods include an interpretation from radiographs based on the implant design specifications listed, implant records, implant recognition software, retrieving implant information through a wireless reader from a radiofrequency chip fitted into an implant screw hole, QR-encoded implant identification wallet, bar code encryption by implant manufacturers, incorporating laser-etched batch and serial numbers in implant collars, Sharma Jhingta system of implant identification and artificial intelligence methods. Amongst existing methods, AI research shows potential in offering a quick and accurate method of implant identification however developing a robust AI model with a comprehensive database is a complex task and requires considerable effort and time.

Survival and Complication Rates of Polymer-Infiltrated Ceramic-Network Single- Tooth Restorations with an Observation Period of up to Three Years.

This study evaluated the clinical performance of a polymer-infiltrated ceramic-network (PICN) material for up to 3 years. Patients (N=286) received 581 indirect restorations as crowns (417), overlays (131), and inlays/veneers (33) fabricated using the PICN (VITA Enamic) by CAD/CAM procedures using intraoral scanning (Cerec Omnicam) and milling systems (Cerec MC XL). The restorations were evaluated annually and in case of complications. Data were analyzed using Kaplan-Meier estimate. Complications were classified as biological or technical failures. Until final recall (mean observation period: 18.3 months) with a dropout rate of 4.8%, 3 biological and 10 technical complications were observed. The overall success rate of the placed restorations was 97.7%. Biological complications included pulpitis and pulp necrosis. Technical complications were debonding (n=7) and fracture (n=3). PICN materials can be used as an alternative to lithium-disilicate or zirconium dioxide for single tooth reconstructions, providing that early failures included debonding and fractures.

Maintenance Costs, Time, and Efforts Following Implant Therapy With Fixed Restorations Over an Observation Period of 10 Years: A Randomized Controlled Clinical Trial.

To assess the costs and efforts of maintenance therapy following implant treatment with fixed restoration over an observation period of 10 years. This randomized controlled clinical trial included 64 patients who were randomly assigned to receive one of two implant systems (AST or STM) and fixed restoration. Patients were included in a regular maintenance program and were examined at loading, 1, 3, 5, 8, and 10 years. Outcome measures included technical and biological complications, time, efforts, and costs to resolve them. A total of 97 implants were placed in 64 patients (AST: 54, STM: 43). Patient recall rates at 5 and 10 years were 89% and 67%. In general, technical complications were resolved within one to two appointments (mean = 1.5), and biological complications required a mean of 1.3 appointments. The overall regular maintenance time for the period of 10 years amounted to 77 min per year. Technical complications occurred in 39.5% of the patients, with screw-loosening being the most common one (43.4% of all complications). The most time-consuming technical complication was abutment fracture (94 min ± 68), followed by screw fracture (84 min ± 38). The prevalence of peri-implant mucositis on the patient level was 30.2%, and it was 9.3% for peri-implantitis. The average annual maintenance costs amounted to 9% of the initial cost of the implant treatment over the period of 10 years. Additional regular maintenance costs and costs due to the treatment of potential complications have to be taken into consideration when placing dental implants. The majority of technical complications could be resolved within one appointment, whereas the time needed to treat biological complications varied between one and three appointments for peri-implantitis.

Application of nanoparticles as surface modifiers of dental implants for revascularization/regeneration of bone

BackgroundOsseointegrated dental implants are widely established as a first-choice treatment for the replacement of missing teeth. Clinical outcomes are however often compromised by short or longer-term biological complications and pathologies. Nanoparticle-coated materials represent a very active research area with the potential to enhance clinical outcomes and reduce complications of implant therapy. This scoping review aimed to summarize current research on various types of nanoparticles (NPs) used as surface modifiers of dental implants and their potential to promote biological and clinical outcomes.MethodsA systematic electronic search was conducted in SCOPUS, PubMed and Google Scholar aiming to identify in vivo, in situ, or in vitro studies published between 2014 and 2024. Inclusion and exclusion criteria were determined and were described in the methods section.ResultsA total of 169 articles (44 original papers from Scopus and PubMed, and 125 articles from Google Scholar) were identified by the electronic search. Finally, 30 studies fit the inclusion criteria and were further used in this review. The findings from the selected papers suggest that nanoparticle-coated dental implants show promising results in enhancing bone regeneration and promoting angiogenesis around the implant site. These effects are due to the unique physicochemical properties of nanoparticle-coated implants and the controlled release of bioactive molecules from nanoparticle-modified surfaces.ConclusionNanoscale modifications displayed unique properties which could significantly enhance the properties of dental implants and further accelerate revascularization, and osseointegration while facilitating early implant loading. Yet, since many of these findings were based on in-vitro/in-situ systems, further research is required before such technology reaches clinical application.

Short implant versus conventional implant in the posterior atrophic maxilla: A systematic review and meta-analysis

Objective: A comparative study undertaken to measure the the marginal bone loss (MBL), implant survival rate, and prosthetic and biological complications among short implants (8 mm or shorter) and conventional implants (longer than 8 mm) in the posterior atrophic maxilla. Materials and Methods: A search in three databases PubMed (Medline), Scopus, and Cochrane was conducted. The present systematic review was registered with identification number CRD42020212805 at the International Prospective Register of Systematic Reviews. Data extraction included the publication year, patients’ number and number of implants, implant length and width, MBL, implant survival rate, and biological and mechanical complications. The Cochrane Risk of Bias 1.0 tool was used to assess the risk of bias. A meta-analysis was performed to evaluate the outcome variables. Comparisons for dichotomous variables, such as prosthetic and biological complications and implant survival rate, were done by applying the Mantel–Haenszel method. In contrast, a comparison was made by applying the inverse variance method for continuous variables like MBL. Results: Initially, 618 reports were recognized from electronic database searches. Five randomized controlled trials (RCTs) were included in the meta-analyses regarding the MBL, implant survival rate, and prosthetic complications, while three were included for biological complications. In 5 years of follow-up, no evidence of difference could be found between conventional and short implants for survival rate (risk ratio [RR]: 3.54; 95% confidence interval [CI]: 0.99–12.67; P = 0.05; I 2 = 0%). We do not find any evidence of difference for MBL between short implants and conventional implants (mean difference: −0.29; 95% CI: −0.49 to −0.08; P = 0.02; I 2 = 65%). Furthermore, no evidence of a difference exists between short and conventional implants for prosthetic complications (RR: 1.56; 95% CI: 0.68–3.55; P = 0.29; I 2 = 0%). The biological complications were seen less with short implants (RR: 0.47; 95% CI: 0.24–0.93; P = 0.03; I 2 = 0%). Conclusion: The results suggest no significant difference among conventional and short implants regarding survival rate in the posterior atrophic maxilla. The results of this systematic review and meta-analysis suggest that, for a 5-year period of follow-up, short implants are related to rarer biological complications and comparable MBL compared to conventional implants. Despite these promising findings, long-term studies with consistent study designs and clinical protocols are required to appraise the performance and durability of short implants.

Retrospective study on the clinical and radiographic outcomes of 2.8 mm diameter implants supporting fixed prostheses up to 11 years.

This study aimed to report the clinical and radiographic results of 2.8 mm two-piece narrow diameter implant (NDI) supporting fixed restorations. Clinical and radiographic data of 54 NDIs in 32 patients were retrospectively assessed after 2 to 11 (mean 8.17) years of follow-up. Clinical and radiographic measurements were taken. Survival rate, implant and prosthesis failure, pink aesthetic scores (PES), white aesthetic scores (WES), bleeding on probing (BOP), probing depth (PD), marginal bone loss (MBL), and mechanical and biological complications were evaluated. An implant failed during the follow-up period, resulting in a cumulative survival rate of 98.15% at the implant level and 96.88% in the patient. The total mean values of PES and WES for 2.8 mm NDIs were 7.09 ± 1.15 (range: 3.33-9.00) and 7.42 ± 1.03 (range: 3.67-9.33). The prevalence of sites with positive BOP was 38.14 ± 29.77%. The mean PD value was 2.46 ± 0.62 mm. The average MBL was 1.15 ± 0.74 mm (range: 0.25-4.03 mm). No implant or abutment fracture was detected. A veneer chipping was present in one patient, and a loose crown appeared in another patient. Two implants (3.7%) and two patients (6.3%) were diagnosed with peri-implantitis. Within the limitation of the study, the results indicate that the use of two-piece 2.8 mm NDI for the fixed prosthetic rehabilitation of edentulous regions with reduced interdental and/or buccal-lingual width is viable.

Subcrestal versus Bone-Level One-Stage Implants: Early Bone and Soft Tissues Modification: One-Year Randomized Clinical Trial

Reducing marginal bone resorption is a challenge in implant dentistry. Sub-gingival implant placement has been suggested as a suitable strategy to avoid long-term esthetic and biological complications. A total of 38 healthy patients received bone-level (BLG-Control) or 2 mm sub-crestal (SCG-Test) conical connection, platform-switched implants. The test group received an immediate tissue-level abutment, following the one-time abutment (OTA) concept. Marginal bone modification (MBM) was calculated on standardized radiographs at surgery (T0), loading (T1), and 6 (T2) and 12 (T3) months after loading and classified as bone loss (BL) if it occurred below the implant neck and bone remodeling (BR) if above. Pocket-probing depth (PPD), Bleeding on probing (BoP), and Plaque Index (PI) were collected. At 12 months, the mean MBM was 0.61 mm in the test group and 0.52 mm in the control group. In all the cases of the test group (SCG), MBM occurred only above the implant neck, therefore being classified as BR, and no BL was observed. In the control group (BLG), MBM occurred below the implant neck, thus corresponding entirely to BL. The test group had an average PPD of 2.38 mm compared to 3.04 mm in the control group, with BoP at 50% and 43%, and PI at 33% and 19.44%, respectively. At one year after loading, sub-crestal conical connection, platform-switched implants show comparable MBM to bone level implants; however, no bone loss was observed.

Survival, technical and biological outcome of fixed tooth- and implant-supported restorations: A retrospective analysis of a patient cohort treated in an undergraduate dental education program

ObjectivesThere is a paucity of data on the outcome of fixed tooth- and implant-supported porcelain-fused-to-metal (PFM) and ceramic-based (CB) restorations fabricated during undergraduate dental education. Therefore, this retrospective study examined the outcome of fixed restorations placed in patients participating in an undergraduate program. MethodsPatient records were searched for data on fixed PFM and CB restorations. For these restorations, the functional period in situ and technical and biological complications, namely restoration fracture, decementation, screw loosening, secondary caries, and loss of vitality, were recorded. Periodontal parameters were also documented. Kaplan-Meier survival and complication estimates after 1 and 5 years were calculated for restoration types, materials, designs (veneered/non-veneered), cementation/retention modes and localizations with group sizes ≥ 15. Regression models were used to analyze the influence of demographic data and abovementioned restoration characteristics on restoration survival, technical and biological outcome. Results1196 restorations with a mean observation time of 5 years were included in the analysis. The different restoration types exhibited survival rates of > 90.8% after 5 years, accompanied by a favorable biological outcome. However, monolithic resin-matrix or feldspathic ceramic restorations were found to have a higher fracture rate than lithium disilicate or zirconium dioxide ceramic restorations resulting in lower survival rates for these restorations. Additionally, resin-matrix ceramic restorations showed a higher decementation rate than lithium disilicate restorations. ConclusionsFixed tooth- and implant-supported CB restorations fabricated from lithium disilicate and zirconium dioxide ceramics demonstrated better survival and lower complication rates than restorations fabricated from resin-matrix or feldspathic ceramics in an undergraduate dental education program. Clinical significanceDue to the more favorable outcome of CB restorations fabricated from lithium disilicate or zirconium dioxide ceramics, undergraduate dental education should focus on the application of these ceramics to increase restoration survival by reducing technical complications.

Clinical outcome of monolithic zirconia on bonded or mechanically retained prefabricated titanium-base: A 4-year retrospective study

ObjectiveTo assess the clinical performance of monolithic screw-retained implant-supported zirconia crowns (MSI) bonded or mechanically retained on prefabricated Ti-bases using a complete digital workflow. MethodsA retrospective analysis was conducted on patients who underwent single dental implant procedures between January 2017 and May 2018. Inclusion criteria were: patients over 18 years of age; implants placed in posterior sites; MSI on prefabricated Ti-base realized by using a complete digital workflow; a minimum follow-up period of 2 years. Cemented crowns and fixed dental prosthesis were excluded. Mechanical complications included: fracture of Ti-base; loss of retention; loosening of Ti-base screws. Technical complications included: fracture and debonding of monolithic zirconia. Biological complication was set strictly at a probing pocket depth of 5 mm and bleeding on probing or pus secretion. ResultsA total of 144 dental implants placed in 127 patients were included, 73 with a fully tapered implant system (BLX) and 71 with a conical connection system (Nobel Parallel CC).Of the 73 BLX implants, 4 experienced loosening of the Ti-base screw, while 3 Nobel Parallel CC implants experienced the same problem. In addition, 4 fractures of the Ti-base and 6 fractures of the inner surface of the monolithic zirconia were observed in the Nobel Parallel CC implants. Cumulative survival was 100 % for bonded crowns and 85 % for mechanically retained crowns. Radiographic evaluation revealed a mean CBL of 0.12 mm for the BLX and 0.13 mm for the Nobel Parallel CC implants with no statistically significant differences between the Ti-base types. There was no evidence of bleeding on probing or pus secretion. All probing pocket depths were <3 mm. ConclusionThe use of a prefabricated Ti-base remains a clinically acceptable choice, however, MSIs bonded to prefabricated Ti-bases had fewer mechanical and technical complications than the MSI mechanically retained to a prefabricated Ti-base.

Biologic Complications Associated with Cylindrical Lead Spinal Cord Stimulator Implants: A Narrative Review

Biologic Complications Associated with Cylindrical Lead Spinal Cord Stimulator Implants: A Narrative Review

Clinical outcomes and supragingival microbiota analysis around dental implants and teeth in patients with a history of periodontitis: a preliminary study of 6 months follow-up.

To investigate the supragingival microbiome surrounding dental implants and neighbouring tooth in periodontitis history and periodontally healthy patients. Subjects with a history of periodontitis (test) and periodontally healthy subjects (control) received one of two types of dental implants with different surface characteristics: sandblasted acid-etched (SLA) or precision dimension laser-treated (PDL). Periodontal clinical measurements were collected at baseline (V1), 3 months after implant placement (V4), at zirconia crown placement (V6) and 3 months after zirconia crown placement (V8). Supragingival bacterial microbiota was studied using Illumina MiSeq sequencing. Supragingival microbial community on SLA implants in test group significantly differed to control group at V8 (p < 0.05). A longitudinal shift displaying microbial dysbiosis occurred on SLA implants (p < 0.05) and adjacent teeth (p < 0.05) among test patients from V6 to V8. On PDL implants and the adjacent tooth, no significant difference between test and control groups from V6 to V8 (p > 0.05). Co-occurrence network in test group of SLA implants and the adjacent tooth at V8 showed increased disease-associated bacteria and reduced health-associated bacteria. Health-associated bacteria were dominant in control group of SLA implants at V8. The surface characteristics and prosthetic components of dental implants may be important risk factors in patients with a history of periodontitis. Dysbiosis of supragingival microbiome may predispose dental implants to peri-implant diseases. Thus, a strict supportive periodontal care plan is imperative to prevent early onset of biological complications.

Immediate versus conventional loading in short and ultra-short implants: a protocol design.

After tooth extraction, inevitable resorption of the postextraction socket occurs. Placing an immediate implant does not fully preserve the bone integrity of the socket. Preservation techniques cannot avoid alveolar resorption. In residual atrophies, bone augmentation techniques are necessary for subsequent rehabilitation with implants. The aim of this study was to propose a protocol of immediate loading in short implants as an alternative to bone augmentation techniques, comparing the immediate versus conventional loading, evaluating peri-implant bone loss, the biological and prosthetic complications, the survival of the implant and prosthesis and the patient satisfaction after one year. This study consists of a randomized controlled clinical trial. For implant planning, periapical intraoral radiographs and Cone Beam Computed Tomography will be used. All patients will receive Straumann Group® (Basel, Switzerland) titanium-zirconia implants with a 4.1mm or 4.8mm diameter and a 4 mm or 6 mm length. The expected results show similar or even minor bone loss, biological and prosthetic complications, identical or even better survival of the short implants with immediate loading, and greater satisfaction. Short implants demonstrate similar survival to conventional length implants, with comparable or even minor biological and prosthetic complications and bone loss. Immediate loading gives satisfactory results similar to conventional loading, with similar biological and prosthetic complications, and generally depends on poor hygiene levels. Bone loss is even less, and the satisfaction increases.

Seven-Year Retrospective Study on Conometric Retention for Complete Fixed Prosthesis

The aim of the present work was to evaluate retrospectively, after seven years of function, the efficacy of a conometric retention to stabilize complete prostheses (CPs) on four implants. Data from twenty-three patients with CPs supported by four implants, with at least seven years of follow up were retrieved. All the CPs were immediately fixed to the implants using a conometric retention. Outcome measures were prosthesis and implant success, biological and prosthetic complications, probing pocket depth changes, marginal bleeding, and plaque index changes. A total of 92 implants were evaluated. No fixture or abutment fractures were reported. No abutment unscrewing was reported. Four framework fractures occurred after three, four, six, and seven years of function. The overall success rate of the rehabilitation was 82.6%. Mucositis was observed in eight patients and 13 implants. No peri-implantitis was recorded. A 0.55 mm difference of PPD and 0.74 mm of MBL was recorded after seven years (p &lt; 0.001). The present implant-supported conometric retention system proved to be effective in giving fixed retention to a CP supported by four implants. Biological complications were easily detected and treated. An adequate metal framework should be provided to the definitive restoration to avoid fractures in the long term.

Survival and complication rates of tooth- and implant-supported restorations after an observation period up to 36 years.

Tooth- and implant-supported fixed dental prostheses are well-documented and aesthetic treatment alternatives, and after a comprehensive periodontal treatment, a protocol with a good long-term prognosis if the maintenance program is strictly followed. To reexamine a pre-existing patient cohort in order to obtain estimated long-term survival and complication outcomes of fixed dental prostheses. For this study, patients treated with fixed dental prostheses between 1978 and 2002 were reexamined between 2019 and 2020. The restorations were divided in single crowns and fixed dental prostheses supported by teeth (TSC, FPTDP) and implants (ISC, FPIDP). Survival and complication rates were obtained. Kaplan-Meier functions were used to model complication probabilities, and average hazard ratios of different strata were compared using weighted Cox regression. The mean observation time of 40 patients and 223 reconstructions was 20.3 (±9.7, 1.2-36.2) years. The estimated survival rates were 84% (CI: 77%-92%) for TSC, 63% (CI: 51%-79%) for FPTDP, 87% (CI: 71%-100%) for ISC, and 64% (CI: 34%-100%) for FPIDP after 25 years. Biological complications included carious lesions (10.6%), periodontitis (7.9%), and peri-implantitis (6.8%). Technical complications included chipping (20.2%) and loss of retention (10.8%). Biological complications lead to abutment loss in more than two-thirds of cases, regardless of the type of abutment (tooth or implant). Technical complications are less associated with abutment loss than biological complications.

Impact Testing in Implant-Supported Prostheses and Natural Teeth: A Systematic Review of Properties and Performance.

Dental implants offer an effective solution for partial and total edentulism, but mechanical and biological complications exist. Furthermore, high occlusal loads challenge implants and lead to potential failures. This review focuses on impact testing in contrast to incremental and static tests, an underexplored aspect of assessing daily loads on implants, bringing to light potential complications. The review examines studies employing impact forces to assess implant-supported prostheses and natural teeth properties, highlighting their significance in dental research. A systematic search following PRISMA guidelines identified 21 relevant articles out of 224, emphasizing studies employing impact forces to evaluate various aspects of dental implant treatments. The diverse applications of impact forces in dental research were categorized into tooth structure, restorative materials, interface evaluation, implant properties, and finite element models. Some studies showed the significance of impact forces in assessing stress distribution, shock absorption, and biomechanical response. Impact testing is a critical tool for understanding the daily forces on implants. Despite diverse experimental approaches, a lack of standardized protocols complicates the systematization of the results and, therefore, the conclusions. This review highlights the need for consistent methodologies in impact testing studies for future research on implant-supported prostheses.

The survival and clinical performance of anterior composite resin restorations and posterior indirect and cast restorations used to treat generalised tooth wear

Objective To evaluate the survival and clinical performance of restorative materials used in the rehabilitation of generalised severe tooth wear within a UK NHS postgraduate teaching hospital.Methods The clinical performance of 527 restorations on 20 patients with generalised severe tooth wear was reviewed after a mean period of five years. Anterior teeth were restored with direct composite resin and posterior teeth with indirect restorations. The study used the modified United States Public Health Service criteria for restoration assessment. Survival of the restorations was analysed using Kaplan-Meier survival curves, the log-rank test and the Cox proportional hazards regression analysis.Results The sample included 20 participants: 13 men and 7 women, with a median age of 51.8 years (range: 33-73 years). The median survival time for all restorations was 11.3 years when major failures were considered and 5.9 years for restorations when all types of failure were considered. A median survival time of 5.9 years for composite resin restorations and over seven years for cast restorations was found when considering all failures. Composite resin restorations commonly failed as a result of fracture, wear and marginal discolouration. Factors significantly influencing restoration survival were the material used, aetiology, incisal relationship and tooth location. The biological complications associated with this treatment regime were rare. Patient satisfaction remained generally high, with greatest dissatisfaction related to treatment time.Conclusions The use of anterior composite resin with posterior indirect restorations to treat generalised severe tooth wear is a viable treatment modality with very few major complications.

Analysis of histomorphology and SERNINA5 gene expression in different regions of epididymis of cattleyak.

The molecular mechanism of sterility in cattleyak is still unresolved. The related factors of infertility in cattleyak were studied by tissue section, SERPINA5 gene cloning and bioinformatics technology. Tissue sections of the epididymis showed poorly structured and disorganized epithelial cells in the corpus of the epididymis compared to the caput of the epididymis, while in the cauda part of the epididymis, the extra basal smooth muscle was thinner, the surface of the epithelial lumen was discontinuous and the epithelium was markedly degenerated. The results of gene cloning showed that the coding sequence (CDS) region of the SERPINA5 gene in cattleyak was 1215bp in length, encoding a total of 404 amino acids, of which the isoleucine content was the highest, accounting for a total of 49 amino acids (12.1%). The results of real-time fluorescence quantitative PCR (qPCR) showed that the expression of the SERPINA5 gene in the epididymis caput in cattleyak was significantly higher than that in the corpus and cauda (P < 0.05), but there were no significant differences between the corpus and cauda. In the current study, histological and bioinformatics analysis, physicochemical properties, and the expression analysis of the SERPINA5 gene in different regions of the epididymis in cattleyak were carried out to explore the biological complications of cattleyak infertility.

Combined laser, guided bone regeneration and probiotics approach in the treatment of periimplantitis: a case report

Biological complications which involve osseointegrated implants created up today a great interest in dentistry, and several kinds of treatments were proposed in these last years to avoid the loss of the implant due to the bone reabsorption. The aim of this case report was to show an original approach to treat periimplantitis by combining the use of Er:YAG and bone guide regeneration during the intervention, followed by a probiotics therapy in the immediate follow-up.