Effectiveness of different intrusion modes of maxillary anterior teeth with mini-implants in clear aligner treatment: a three-dimensional finite element analysis.

BACKGROUND: The intrusion of maxillary anterior teeth is often required and there are various intrusion modes with mini-implants in clear aligner treatment. The objective of this study was to evaluate the effectiveness of maxillary anterior teeth intrusion with different intrusion modes, aiming to provide references for precise and safe intrusion movements in clinical practice. METHODS: Cone-beam computed tomography and intraoral optical scanning data of a patient were collected. Finite element models of the maxilla, maxillary dentition, periodontal ligaments (PDLs), clear aligner (CA), attachments, and mini-implants were established. Different intrusion modes of the maxillary anterior teeth were simulated by changing the mini-implant site (between central incisors, between central and lateral incisor, between lateral incisor and canine), loading site (between central incisors, on central incisor, between central and lateral incisor, between lateral incisor and canine), and loading mode (labial loading and labiolingual loading). Ten conditions were generated and intrusive forces of 100 g were applied totally. Then displacement tendency of the maxillary anterior teeth and CA, and stress of the PDLs were analyzed. RESULTS: For the central incisor under condition L14 and for the canine under conditions L11, L13, L23, and L33, the intrusion amount was negative. Under other conditions, the intrusion amount was positive. The labiolingual angulation of maxillary anterior teeth exhibited positive changes under all conditions, with greater changes under linguoincisal loading. The mesiodistal angulation of canine exhibited positive changes under labial loading, while negative changes under linguoincisal loading except for condition L14. CONCLUSIONS: The intrusion amount, labiolingual and mesiodistal angulations of the maxillary anterior teeth were affected by the mini-implant site, loading site, and loading mode. Labial and linguoincisal loading may have opposite effects on the intrusion amount of maxillary anterior teeth and the mesiodistal angulation of canine. The labiolingual angulation of the maxillary incisors would increase under all intrusion modes, with greater increases under linguoincisal loading.

THE IMPACT OF SYSTEMIC DRUGS ON DENTAL IMPLANT OSSEOINTEGRATION: A REVIEW.

The process of osteointegration of dental implants is a biological process. Systemic therapy can interfere with this process, affecting the growth and breakdown processes of the bone and ultimately leading to implant failure. This literature review focuses on specific groups of systemic drugs that directly impact osteointegration. The research in electronic literature was conducted using the National Library of Medicine's PubMed/MEDLINE database from March 2000 to February 2024. The following MeSH (Medical Subject Headings) terms were used: "implant osseointegration," "bisphosphonates," "non-steroidal anti-inflammatory drugs," "glucocorticoids," "proton pump inhibitors," and "selective serotonin reuptake inhibitors (SSRIs)." This search yielded 1,258 articles on implant osseointegration. Among these, 30 articles met our criteria for implant osseointegration and bisphosphonates, 2 articles for non-steroidal anti-inflammatory drugs (NSAIDs), 7 articles for glucocorticoids, 14 articles for proton pump inhibitors (PPIs), and 14 articles for selective serotonin reuptake inhibitors (SSRIs). Clinicians considering implant therapy should be mindful of potential medication-related implant failures. The present systematic review has identified an association between proton pump inhibitors (PPIs), nonsteroidal anti-inflammatory drugs (NSAIDs), selective serotonin reuptake inhibitors (SSRIs), glucocorticoids, and bisphosphonates with an increased implant failure rate.

Correlation Between Implant Stability Quotient and Percussion Sound Frequency.

OBJECTIVES: To determine the correlation between the primary implant stability quotient and the implant percussion sound frequency. MATERIALS AND METHODS: A total of 14 pigs' ribs were scanned using a dental cone beam computed tomography (CBCT) scanner to classify the bone specimens into three distinct bone density Hounsfield units (HU) value categories: D1 bone: >1250 HU; D2: 850-1250 HU; D3: <850 HU. Then, 96 implants were inserted: 32 implants in D1 bone, 32 implants in D2 bone, and 32 implants in D3 bone. The primary implant stability quotient (ISQ) was analyzed, and percussion sound was recorded using a wireless microphone connected and analyzed with frequency analysis software. RESULTS: Statistically significant positive correlations were found between the primary ISQ and the bone density HU value (r = 0.719; p < 0.001), and statistically significant positive correlations between the primary ISQ and the percussion sound frequency (r = 0.606; p < 0.001). Furthermore, significant differences in primary ISQ values and percussion sound frequency were found between D1 and D2 bone, as well as between D1 and D3 bone. However, no significant differences were found in primary ISQ values and percussion sound frequency between D2 and D3 bone. CONCLUSION: The primary ISQ value and the percussion sound frequency are positively correlated.

Xenogeneic Collagen Matrix Versus Free Gingival Graft for Augmenting Peri-Implant Keratinized Mucosa Around Dental Implants: A Systematic Review and Meta-Analysis.

OBJECTIVES: There is a growing evidence to suggest augmenting peri-implant keratinized mucosa in the presence of ≤ 2 mm of keratinized mucosa. However, the most appropriate surgical technique and augmentation materials have yet to be defined. The aim of this systematic review and meta-analyses was to evaluate the clinical and patient-reported outcomes of augmenting keratinized mucosa around implants using free gingival graft (FGG) versus xenogeneic collagen matrix (XCM) before commencing prosthetic implant treatment. MATERIAL AND METHODS: Electronic databases were searched to identify observational studies comparing implant sites augmented with FGG to those augmented with XCM. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool. RESULTS: Six studies with 174 participants were included in the present review. Of these, 87 participants had FGG, whereas the remaining participants had XCM. At 6 months, sites augmented with FGG were associated with less changes in the gained width of peri-implant keratinized mucosa compared to those augmented with XCM (mean difference 1.06; 95% confidence interval -0.01 to 2.13; p = 0.05). The difference, however, was marginally significant. The difference between the two groups in changes in thickness of peri-implant keratinized mucosa at 6 months was statistically significantly in favor of FGG. On the other hand, XCM had significantly shorter surgical time, lower postoperative pain score, and higher color match compared to FGG. CONCLUSIONS: Within the limitation of this review, the augmentation of keratinized mucosa using FGG before the placement of the final prosthesis may have short-term positive effects on soft tissue thickness. XCM might be considered in aesthetically demanding implant sites and where patient comfort or shorter surgical time is a priority. The evidence support, however, is of low to moderate certainty; therefore, further studies are needed to support the findings of the present review.

Multi-objective optimization of custom implant abutment design for enhanced bone remodeling in single-crown implants using 3D finite element analysis.

The optimal configuration of a customized implant abutment is crucial for bone remodeling and is influenced by various design parameters. This study introduces an optimization process for designing two-piece zirconia dental implant abutments. The aim is to enhance bone remodeling, increase bone density in the peri-implant region, and reduce the risk of late implant failure. A 12-month bone remodeling algorithm subroutine in finite element analysis to optimize three parameters: implant placement depth, abutment taper degree, and gingival height of the titanium base abutment. The response surface analysis shows that implant placement depth and gingival height significantly impact bone density and uniformity. The taper degree has a smaller effect on bone remodeling. The optimization identified optimal values of 1.5 mm for depth, 35° for taper, and 0.5 mm for gingival height. The optimum model significantly increased cortical bone density from 1.2 to 1.937 g/cm3 in 2 months, while the original model reached 1.91 g/cm3 in 11 months. The standard deviation of density showed more uniform bone apposition, with the optimum model showing values 2 to 6 times lower than the original over 12 months. The cancellous bone showed a similar trend. In conclusion, the depth and taper have a significant effect on bone remodeling. This optimized model significantly improves bone density uniformity.

The Addition of Hydroxyapatite Nanoparticles on Implant Surfaces Modified by Zirconia Blasting and Acid Etching to Enhance Peri-Implant Bone Healing.

This study investigated the impact of adding hydroxyapatite nanoparticles to implant surfaces treated with zirconia blasting and acid etching (ZiHa), focusing on structural changes and bone healing parameters in low-density bone sites. The topographical characterization of titanium discs with a ZiHa surface and a commercially modified zirconia-blasted and acid-etched surface (Zi) was performed using scanning electron microscopy, profilometry, and surface-free energy. For the in vivo assessment, 22 female rats were ovariectomized and kept for 90 days, after which one implant from each group was randomly placed in each tibial metaphysis of the animals. Histological and immunohistochemical analyses were performed at 14 and 28 days postoperatively (decalcified lab processing), reverse torque testing was performed at 28 days, and histometry from calcified lab processing was performed at 60 days The group ZiHa promoted changes in surface morphology, forming evenly distributed pores. For bone healing, ZiHa showed a greater reverse torque, newly formed bone area, and bone/implant contact values compared to group Zi (p < 0.05; t-test). Qualitative histological and immunohistochemical analyses showed higher features of bone maturation for ZiHa on days 14 and 28. This preclinical study demonstrated that adding hydroxyapatite to zirconia-blasted and acid-etched surfaces enhanced peri-implant bone healing in ovariectomized rats. These findings support the potential for improving osseointegration of dental implants, especially in patients with compromised bone metabolism.

Influence of the Surface Topography of Titanium Dental Implants on the Behavior of Human Amniotic Stem Cells.

The dental implant surface plays a crucial role in osseointegration. The topography and physicochemical properties will affect the cellular functions. In this research, four distinct titanium surfaces have been studied: machined acting (MACH), acid etched (AE), grit blasting (GBLAST), and a combination of grit blasting and subsequent acid etching (GBLAST + AE). Human amniotic mesenchymal (hAMSCs) and epithelial stem cells (hAECs) isolated from the amniotic membrane have attractive stem-cell properties. They were cultured on titanium surfaces to analyze their impact on biological behavior. The surface roughness, microhardness, wettability, and surface energy were analyzed using interferometric microscopy, Vickers indentation, and drop-sessile techniques. The GBLAST and GBLAST + AE surfaces showed higher roughness, reduced hydrophilicity, and lower surface energy with significant differences. Increased microhardness values for GBLAST and GBLAST + AE implants were attributed to surface compression. Cell viability was higher for hAMSCs, particularly on GBLAST and GBLAST + AE surfaces. Alkaline phosphatase activity enhanced in hAMSCs cultured on GBLAST and GBLAST + AE surfaces, while hAECs showed no mineralization signals. Osteogenic gene expression was upregulated in hAMSCs on GBLAST surfaces. Moreover, α2 and ß1 integrin expression enhanced in hAMSCs, suggesting a surface-integrin interaction. Consequently, hAMSCs would tend toward osteoblastic differentiation on grit-blasted surfaces conducive to osseointegration, a phenomenon not observed in hAECs.

[Effects of cortical bone thickness and jaw bone density on pain during implant surgery].

PURPOSE: To investigate the effects of different cortical bone thickness and jaw bone density at implant sites on intraoperative pain during implant surgery. METHODS: One hundred and eighty-seven patients(263 implant sites) who underwent implant placement surgery at the Fourth Affiliated Hospital of Nanchang University from August 2021 to August 2022 were selected to investigate the effects of different cortical bone thickness and jaw bone density HU values at implant sites on the anesthetic effect under local infiltration anesthesia with epinephrine in articaine. SPSS 26.0 software package was used for data analysis. RESULTS: The mean cortical bone thickness at the painful sites[(3.90±1.36) mm] was significantly greater than that at the non-painful sites [(2.24±0.66) mm], and the difference was statistically significant(P＜0.05). The differences in cortical bone thickness in the mandibular anterior, premolar, and molar regions were statistically significant in the comparison of pain and non-pain sites. The mean HU value of bone density was (764.46±239.75) for the painful sites and (612.23±235.31) for the non-painful sites, with significant difference(P＜0.05). The difference was not significant(P＞0.05) when comparing the HU values of painful sites with non-painful sites in the mandibular anterior teeth and anterior molar region, while the difference was significant(P＜0.05) when comparing the HU values of painful sites with non-painful sites in the mandibular molar region. CONCLUSIONS: Sites with large cortical bone thickness have a greater effect on blocking infiltrative anesthetic penetration and are more prone to intraoperative pain during implantation. In the mandibular anterior and premolar regions, the HU value of the implant sites had less effect on infiltrative anesthetic penetration, and the effect was greater in the mandibular molar region, and the implant sites with high HU values in the mandibular molar region were more likely to have intraoperative pain. When the cortical bone thickness in the planned implant site is greater than 3.9 mm and the mean bone density in the mandibular molar region is greater than 665 HU. If there is sufficient safe distance for hole operation, it is recommended to apply mandibular nerve block anesthesia combined with articaine infiltration anesthesia to avoid intraoperative pain and bad surgical experience for the patients.

Nanofeatured surfaces in dental implants: contemporary insights and impending challenges.

Dental implant therapy, established as standard-of-care nearly three decades ago with the advent of microrough titanium surfaces, revolutionized clinical outcomes through enhanced osseointegration. However, despite this pivotal advancement, challenges persist, including prolonged healing times, restricted clinical indications, plateauing success rates, and a notable incidence of peri-implantitis. This review explores the biological merits and constraints of microrough surfaces and evaluates the current landscape of nanofeatured dental implant surfaces, aiming to illuminate strategies for addressing existing impediments in implant therapy. Currently available nanofeatured dental implants incorporated nano-structures onto their predecessor microrough surfaces. While nanofeature integration into microrough surfaces demonstrates potential for enhancing early-stage osseointegration, it falls short of surpassing its predecessors in terms of osseointegration capacity. This discrepancy may be attributed, in part, to the inherent "dichotomy kinetics" of osteoblasts, wherein increased surface roughness by nanofeatures enhances osteoblast differentiation but concomitantly impedes cell attachment and proliferation. We also showcase a controllable, hybrid micro-nano titanium model surface and contrast it with commercially-available nanofeatured surfaces. Unlike the commercial nanofeatured surfaces, the controllable micro-nano hybrid surface exhibits superior potential for enhancing both cell differentiation and proliferation. Hence, present nanofeatured dental implants represent an evolutionary step from conventional microrough implants, yet they presently lack transformative capacity to surmount existing limitations. Further research and development endeavors are imperative to devise optimized surfaces rooted in fundamental science, thereby propelling technological progress in the field.

Accuracy of computer-guided implant surgery in partially edentulous patients: a prospective observational study.

PURPOSE: This study aims to evaluate the amount of distortion using computer-guided implant surgery with 3D printed surgical guides in limited edentulous spaces. MATERIALS AND METHODS: 25 bone level self-tapping implants (Straumann® BL and BLT) were randomly inserted in either distal or intercalary posterior mandibular edentulism using a fully digital protocol and 3D printed surgical guides. Amount of inaccuracy was evaluated after superimposing the 3 coordinates of virtually planned and final implant images, which were obtained using intra-oral scans and scan bodies. Four evaluation parameters were considered: origo-displacement, error depth, apical displacement and angle between the planned and the placed implant. RESULTS: The average of distortion was 0.71 mm for the origo-displacement, 0.36 mm for the error depth, 0.52 mm for the horizontal displacement and 3.34º for the error angle. CONCLUSION: The major reason of exclusion was CBCT artifacts. Results of this study were aligned with the results of previous studies concerning partially edentulous spaces. CAD/CAM manufacturing process did not result in significant distortion whilst the biggest part of distortions originated from the surgical process. The learning curve in computer-guided implant surgery presented an important source of inaccuracy.

Nano-Based Approaches in Surface Modifications of Dental Implants: A Literature Review.

Rehabilitation of fully or partially edentulous patients with dental implants represents one of the most frequently used surgical procedures. The work of Branemark, who observed that a piece of titanium embedded in rabbit bone became firmly attached and difficult to remove, introduced the concept of osseointegration and revolutionized modern dentistry. Since then, an ever-growing need for improved implant materials towards enhanced material-tissue integration has emerged. There is a strong belief that nanoscale materials will produce a superior generation of implants with high efficiency, low cost, and high volume. The aim of this review is to explore the contribution of nanomaterials in implantology. A variety of nanomaterials have been proposed as potential candidates for implant surface customization. They can have inherent antibacterial properties, provide enhanced conditions for osseointegration, or act as reservoirs for biomolecules and drugs. Titania nanotubes alone or in combination with biological agents or drugs are used for enhanced tissue integration in dental implants. Regarding immunomodulation and in order to avoid implant rejection, titania nanotubes, graphene, and biopolymers have successfully been utilized, sometimes loaded with anti-inflammatory agents and extracellular vesicles. Peri-implantitis prevention can be achieved through the inherent antibacterial properties of metal nanoparticles and chitosan or hybrid coatings bearing antibiotic substances. For improved corrosion resistance various materials have been explored. However, even though these modifications have shown promising results, future research is necessary to assess their clinical behavior in humans and proceed to widespread commercialization.

Beyond microroughness: novel approaches to navigate osteoblast activity on implant surfaces.

Considering the biological activity of osteoblasts is crucial when devising new approaches to enhance the osseointegration of implant surfaces, as their behavior profoundly influences clinical outcomes. An established inverse correlation exists between osteoblast proliferation and their functional differentiation, which constrains the rapid generation of a significant amount of bone. Examining the surface morphology of implants reveals that roughened titanium surfaces facilitate rapid but thin bone formation, whereas smooth, machined surfaces promote greater volumes of bone formation albeit at a slower pace. Consequently, osteoblasts differentiate faster on roughened surfaces but at the expense of proliferation speed. Moreover, the attachment and initial spreading behavior of osteoblasts are notably compromised on microrough surfaces. This review delves into our current understanding and recent advances in nanonodular texturing, meso-scale texturing, and UV photofunctionalization as potential strategies to address the "biological dilemma" of osteoblast kinetics, aiming to improve the quality and quantity of osseointegration. We discuss how these topographical and physicochemical strategies effectively mitigate and even overcome the dichotomy of osteoblast behavior and the biological challenges posed by microrough surfaces. Indeed, surfaces modified with these strategies exhibit enhanced recruitment, attachment, spread, and proliferation of osteoblasts compared to smooth surfaces, while maintaining or amplifying the inherent advantage of cell differentiation. These technology platforms suggest promising avenues for the development of future implants.

Evaluation of the accuracy of conventional and digital implant impression techniques in bilateral distal extension cases: a randomized clinical trial.

BACKGROUND: This clinical study aims to evaluate the accuracy of the conventional implant impression techniques compared to the digital impression ones in bilateral distal extension cases. METHODS: A total of 32 implants were placed in eight patients missing all mandibular posterior teeth except the first premolars. Each patient received a total of four implants, with two implants placed on each side, in order to provide support for three units of screw-retained zirconia restorations. Following osteointegration, the same patient underwent two implant-level impression techniques: Conventional open-tray impressions CII (splinted pick-up) and digital implant impressions DII with TRIOS 3 Shape intraoral scanner. The accuracy of impressions was evaluated utilizing a three-dimensional superimposition analysis of standard tessellation language (STL) files. Subsequently, the scan bodies were segmented using Gom inspect software to measure three-dimensional deviations in a color-coding map. Data were statistically analyzed using the Kruskal Wallis test and then a post-hoc test to determine the significance level (P < 0.05). RESULTS: The study revealed that higher angular and positional deviations were shown toward distal scan bodies compared to mesial ones for both impression techniques. However, this difference was not statistically significant (P > 0.05). CONCLUSION: Splinted open-tray conventional impression and intraoral scanning implant impression techniques have demonstrated comparable accuracy. TRIAL REGISTRATION: Clinical Trials.gov Registration ID NCT05912725. Registered 22/06/ 2023- Retrospectively registered, https://register. CLINICALTRIALS: gov .

The role of bone ring technique for bone augmentation in implant surgery: A Narrative Review.

Bone grafting with simultaneous implant placement using the novel bone ring technique was a procedure introduced with the intention of three-dimensional bone augmentation with simultaneous implant placement in both maxilla and mandible. A ring-shaped bone is placed in the socket, which is secured by an implant placed through the ring. The current narrative review was planned to provide a concise summary of the core concepts surrounding bone augmentation, to provide context for understanding the bone ring technique, and to highlight the basics of bone grafting and the origin of the technique to its advancement and its importance in the light of current literature.

Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri-implant diseases.

BACKGROUND: Periodontitis and peri-implant diseases are chronic inflammatory conditions occurring in the mouth. Left untreated, periodontitis progressively destroys the tooth-supporting apparatus. Peri-implant diseases occur in tissues around dental implants and are characterised by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone. Treatment aims to clean the pockets around teeth or dental implants and prevent damage to surrounding soft tissue and bone, including improvement of oral hygiene, risk factor control (e.g. encouraging cessation of smoking) and surgical interventions. The key aspect of standard non-surgical treatment is the removal of the subgingival biofilm using subgingival instrumentation (SI) (also called scaling and root planing). Antimicrobial photodynamic therapy (aPDT) can be used an adjunctive treatment to SI. It uses light energy to kill micro-organisms that have been treated with a light-absorbing photosensitising agent immediately prior to aPDT. OBJECTIVES: To assess the effects of SI with adjunctive aPDT versus SI alone or with placebo aPDT for periodontitis and peri-implant diseases in adults. SEARCH METHODS: We searched the Cochrane Oral Health Trials Register, CENTRAL, MEDLINE, Embase, two other databases and two trials registers up to 14 February 2024. SELECTION CRITERIA: We included randomised controlled trials (RCTs) (both parallel-group and split-mouth design) in participants with a clinical diagnosis of periodontitis, peri-implantitis or peri-implant disease. We compared the adjunctive use of antimicrobial photodynamic therapy (aPDT), in which aPDT was given after subgingival or submucosal instrumentation (SI), versus SI alone or a combination of SI and a placebo aPDT given during the active or supportive phase of therapy. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures, and we used GRADE to assess the certainty of the evidence. We prioritised six outcomes and the measure of change from baseline to six months after treatment: probing pocket depth (PPD), bleeding on probing (BOP), clinical attachment level (CAL), gingival recession (REC), pocket closure and adverse effects related to aPDT. We were also interested in change in bone level (for participants with peri-implantitis), and participant satisfaction and quality of life. MAIN RESULTS: We included 50 RCTs with 1407 participants. Most studies used a split-mouth study design; only 18 studies used a parallel-group design. Studies were small, ranging from 10 participants to 88. Adjunctive aPDT was given in a single session in 39 studies, in multiple sessions (between two and four sessions) in 11 studies, and one study included both single and multiple sessions. SI was given using hand or power-driven instrumentation (or both), and was carried out prior to adjunctive aPDT. Five studies used placebo aPDT in the control group and we combined these in meta-analyses with studies in which SI alone was used. All studies included high or unclear risks of bias, such as selection bias or performance bias of personnel (when SI was carried out by an operator aware of group allocation). We downgraded the certainty of all the evidence owing to these risks of bias, as well as for unexplained statistical inconsistency in the pooled effect estimates or for imprecision when evidence was derived from very few participants and confidence intervals (CI) indicated possible benefit to both intervention and control groups. Adjunctive aPDT versus SI alone during active treatment of periodontitis (44 studies) We are very uncertain whether adjunctive aPDT during active treatment of periodontitis leads to improvement in any clinical outcomes at six months when compared to SI alone: PPD (mean difference (MD) 0.52 mm, 95% CI 0.31 to 0.74; 15 studies, 452 participants), BOP (MD 5.72%, 95% CI 1.62 to 9.81; 5 studies, 171 studies), CAL (MD 0.44 mm, 95% CI 0.24 to 0.64; 13 studies, 414 participants) and REC (MD 0.00, 95% CI -0.16 to 0.16; 4 studies, 95 participants); very low-certainty evidence. Any apparent differences between adjunctive aPDT and SI alone were not judged to be clinically important. Twenty-four studies (639 participants) observed no adverse effects related to aPDT (moderate-certainty evidence). No studies reported pocket closure at six months, participant satisfaction or quality of life. Adjunctive aPDT versus SI alone during supportive treatment of periodontitis (six studies) We were very uncertain whether adjunctive aPDT during active treatment of periodontitis leads to improvement in any clinical outcomes at six months when compared to SI alone: PPD (MD -0.04 mm, 95% CI -0.19 to 0.10; 3 studies, 125 participants), BOP (MD 4.98%, 95% CI -2.51 to 12.46; 3 studies, 127 participants), CAL (MD 0.07 mm, 95% CI -0.26 to 0.40; 2 studies, 85 participants) and REC (MD -0.20 mm, 95% CI -0.48 to 0.08; 1 study, 24 participants); very low-certainty evidence. These findings were all imprecise and included no clinically important benefits for aPDT. Three studies (134 participants) reported adverse effects: a single participant developed an abscess, though it is not evident whether this was related to aPDT, and two studies observed no adverse effects related to aPDT (moderate-certainty evidence). No studies reported pocket closure at six months, participant satisfaction or quality of life. AUTHORS' CONCLUSIONS: Because the certainty of the evidence is very low, we cannot be sure if adjunctive aPDT leads to improved clinical outcomes during the active or supportive treatment of periodontitis; moreover, results suggest that any improvements may be too small to be clinically important. The certainty of this evidence can only be increased by the inclusion of large, well-conducted RCTs that are appropriately analysed to account for change in outcome over time or within-participant split-mouth study designs (or both). We found no studies including people with peri-implantitis, and only one study including people with peri-implant mucositis, but this very small study reported no data at six months, warranting more evidence for adjunctive aPDT in this population group.

Is immediate dental implant in fibula free flap beneficial for implant survival and osteoradionecrosis in jaw reconstruction?

OBJECTIVES: This study aimed to compare the risk of osteoradionecrosis and implant survival in oral cancer patients undergoing immediate dental implants during jaw reconstruction, termed "Jaw in a Day" (JIAD), with those receiving no implants or delayed implants (non-JIAD). PATIENTS & METHODS: Clinicopathologic data were collected from prospectively enrolled JIAD patients (n = 10, 29 implants) and retrospectively from non-JIAD patients (n = 117, 86 implants). Survival analyses were performed to assess implant survival and osteoradionecrosis-free survival. RESULTS: Osteoradionecrosis occurred in 0 % of JIAD cases compared to 19.3 % in non-JIAD cases without implants and 71.4 % in non-JIAD cases with delayed implants (p = 0.008). Osteoradionecrosis-free survival was significantly better in the JIAD group than the non-JIAD group (p = 0.0059). Implants in the JIAD group all survived regardless of radiation therapy (29/29, 100 %) and 95.1 % (58/61) of implants survived in delayed implants in non-irradiated fibula without radiotherapy. Meanwhile, only 11 of 25 implants placed in irradiated fibula flaps survived, even when the implants were placed after a median time interval of 624 days after radiotherapy, and none of them were earlier than 360 days. The survival analysis revealed a significant difference (p < 0.0001). CONCLUSION: JIAD appears to offer superior outcomes in terms of implant survival and osteoradionecrosis prevention compared to delayed implant placement. Placing implants in irradiated fibula, even after years, significantly poses high risk of implant failure and osteoradionecrosis. JIAD represents a promising approach for optimal rehabilitation, particularly in oral cancer patients requiring postoperative radiotherapy. Proper positioning and orientation of implants and flaps are crucial for implant survival.

Antimicrobial Potential of Strontium-Functionalized Titanium Against Bacteria Associated With Peri-Implantitis.

OBJECTIVES: To explore the antimicrobial potential of strontium (Sr)-functionalized wafers against multiple bacteria associated with per-implant infections, in both mono- and multispecies biofilms. MATERIALS AND METHODS: The bactericidal and bacteriostatic effect of silicon wafers functionalized with a strontium titanium oxygen coating (Sr-Ti-O) or covered only with Ti (controls) against several bacteria, either grown as a mono-species or multispecies biofilms, was assessed using a bacterial viability assay and a plate counting method. Mono-species biofilms were assessed after 2 and 24 h, while the antimicrobial effect on multispecies biofilms was assessed at Days 1, 3, and 6. The impact of Sr functionalization on the total percentage of Porphyromonas gingivalis in the multispecies biofilm, using qPCR, and gingipain activity was also assessed. RESULTS: Sr-functionalized wafers, compared to controls, were associated with statistically significant less viable cells in both mono- and multispecies tests. The number of colony forming units (CFUs) within the biofilm was significantly less in Sr-functionalized wafers, compared to control wafers, for Staphylococcus aureus at all time points of evaluation and for Escherichia coli at Day 1. Gingipain activity was less in Sr-functionalized wafers, compared to control wafers, and the qPCR showed that P. gingivalis remained below detection levels at Sr-functionalized wafers, while it consisted of 15% of the total biofilm on control wafers at Day 6. CONCLUSION: Sr functionalization displayed promising antimicrobial potential, possessing bactericidal and bacteriostatic ability against bacteria associated with peri-implantitis grown either as mono-species or mixed in a multispecies consortium with several common oral microorganisms.

A microtomographic and histopathological evaluation of dental cements as late-stage peri-implant complication in a rat model.

Cement mediated peri-implantitis accounts for 1.9-75% of dental implant failures associated with peri-implant diseases. This study evaluated the biological impact of dental cements on osseointegrated implants using Lewis rats. Twenty-two rats were distributed into 6 groups: negative control (NC) soft diet (SD), and hard diet (HD); positive control SD and HD (n = 3); Implant + bio-ceramic Cement (BC) SD and HD which included contralateral Sham sites (n = 5). Titanium implants were placed on either side of the maxillae and allowed to heal for 14 days. Later, both sides of experimental groups underwent a re-entry surgery to simulate clinical cementation. The right side received 0.60 mg of BC. At 14 days post cement application, maxillae were harvested for clinical, microtomographic, and histological evaluations. Clinical and microtomographic evaluations indicated evidence of extensive inflammation and circumferential bone resorption around BC implants in comparison to NC. Histology revealed cement particles surrounded by inflammatory infiltrate in the implant area accompanied by biofilm for SD groups. Both sides of BC indicated intensive bone resorption accompanied by signs of osteolysis when compared to NC. Cemented groups depicted significantly lower bone to implant contact when compared to NC. In conclusion, residual cement extravasation negatively impacted osseointegrated implants after re-entry surgeries.

Simulating the Entire Clinical Process for an Implant-Supported Fixed Prosthesis: In Vitro Study on the Vertical Implications of Implant-Abutment Connections and Rotational Freedom.

OBJECTIVES: The aim of this in vitro study was to investigate whether and to what extent different scenarios of rotational freedom in different IAC designs affect the vertical dimension of a three-part fixed partial denture (FPD). At the same time, the experimental setup should simulate all clinical and laboratory steps of the implementation of such an FPD as accurately as possible. MATERIAL AND METHODS: Twenty identical pairs of jaw models were fabricated from aluminum, each lower-jaw model holding two implants with conical or flat IACs. Three impressions of each model were taken to fabricate stone casts and three-unit FPDs. Three assembly scenarios were compared for the vertical position stability they offered for these FPDs, differing by how the sequential implant components (impression posts > laboratory analogs > abutments 1 > abutments 2) were aligned with the positional index of the IAC. In this way, a total of 60 stone casts and FPDs were fabricated and statistically analyzed for changes in vertical dimension (p < 0.05). RESULTS: Regardless of whether a conical/flat IAC was used (p > 0.05), significantly greater mean changes in vertical dimension were consistently (all comparisons p < 0.0001) found in a "worst-case scenario" of component alignment alternating between the left- and right-limit stop of the positional index (0.286/0.350 mm) than in a "random scenario" of 10 dentists and 10 technicians with varying levels of experience freely selecting the alignment (0.003/0.014 mm) or in a "best-case scenario" of all components being aligned with the right-limit stop (-0.019/0.005 mm). CONCLUSIONS: The likelihood of integrating a superstructure correctly in terms of vertical dimension appears to vary considerably more with assembly strategies than with IAC designs. Specifically, our findings warrant a recommendation that all implant components should be aligned with the right-limit stop of the positioning index.

A Simplified Bone Regeneration Technique for Implant Placement Using a Titanium Membrane.

The treatment of edentulism with dental implants is often combined with hard- and soft-tissue grafting procedures as a means to improve marginal bone stability and esthetic outcomes. One such method of hard-tissue grafting involves the utilization of a titanium membrane as a space maintenance device to contain the graft material and support the soft tissue. These membranes, however, are typically limited in their ability to be customized and, therefore, are often unsuitable for varying clinical situations. This case report presents a simplified prototype design of an abutment-associated titanium membrane. This design enables a greater level of customization and demonstrates stable clinical and radiographic results after 2 years of follow-up.