Aim
The objective of this randomized clinical trial was to investigate the influence of the time of implant placement (immediate vs. early) and the time of restoration (immediate vs. early) on ...esthetic outcome in maxillary anterior single implants.
Material and methods
Forty‐eight patients with a single failing incisor in the maxilla and a natural contralateral site were randomly distributed into four groups. Treatment variations affected the time of implant placement (immediate or early) as well as the time of restoration (immediate or early) – in detail, group 1a with immediate implant placement and immediate temporary restoration, group 1b with immediate implant placement and early restoration, group 2a with early implant placement and immediate temporary restoration, and group 2b with early implant placement and early restoration. All patients received the final prosthetic restoration 10–12 weeks after implant placement. Standardized photographs were taken eight months after tooth extraction. Five competent observers analyzed the esthetic outcome according to the PES after Fürhauser. For statistical analysis, the Kruskal–Wallis test and Dunn's post hoc test were applied. Interobserver reliability was evaluated by Krippendorff's alpha.
Results
The overall scores of the four treatment groups revealed PES values of 8.47 (SD 2.08, group 1a), 7.93 (SD 3.21, group 1b), 6.62 (SD 3.24, group 2a), and 8.10 (SD 3.25, group 2b). The differences between groups 2a and 1a and between groups 2a and 2b were statistically significant (P = 0.015 and P = 0.047). The single parameter analysis displayed a certain range of fluctuation and heterogeneity.
Conclusions
Immediate implant placement and restoration appear to be a viable alternative to early implant placement if an experienced surgeon is entrusted with the implantation procedure.
The esthetic outcome of dental implants can be compromised when some degree of bone loss occurs around the implant. This may particularly affect the tissue-level (TL) design. Therefore, bone-level ...(BL) design implants may be preferable if a natural emergence profile is important. Notwithstanding the implant design, the gingival biotype has been identified as a crucial factor in the stability of crestal bone. The objective of this study was to investigate bone loss in patients with different gingival biotypes at TL and BL implant sites in the esthetic zone.
In 41 patients, 20 TL and 22 BL implant procedures were carried out. Intraoral radiographs of all of the 42 sites were taken immediately after implant insertion as well as during the follow-up examination. The analysis of bone height was conducted using a computerized technique. The TRAN method was used to determine the gingival biotype.
After a mean in situ period of 4.9 years in the TL group, 12 implants with a thick biotype had a mean bone loss of 0.21 mm (SD: 0.43 mm). The eight implants with a thin biotype had a loss of 0.05 mm (SD: 0.47 mm; P = .31). After a mean in situ period of 1.9 years, the 14 BL sites with a thick biotype showed a mean bone change of -0.03 mm (SD: 0.38 mm). In the eight implants with a thin biotype, a change of +0.09 mm (SD: 0.32 mm; P = .84) was noted.
Analysis of the obtained results did not reveal a dependency of bone height on implant design or on gingival biotype. However, prior to choosing an implant design, it may nevertheless be beneficial to screen for transparent soft tissues, where the BL design offers a more natural emergence profile. For this purpose, the TRAN method is clearly the fastest and easiest.
The aim of this study was to assess and compare the esthetic outcome of tissue-level (TL) and bone-level (BL) implants that had been placed as single implants in the anterior maxilla.
Between 2001 ...and 2008, patients were treated using TL implants (Straumann). From 2008 until 2012, patients received the newly developed BL implant (Straumann). All patients with a single anterior maxillary implant who came to check-ups regularly were contacted and invited to take part in the study. Standardized photographs were taken to conduct the evaluation. Five observers analyzed the esthetic outcome using the pink esthetic score (PES). For the purpose of statistical analysis, the Wilcoxon rank sum test was applied. Interobserver reliability was evaluated with Krippendorff's alpha.
Forty-six patients agreed to take part in the study. The study comprised 10 immediate (TL = 6, BL = 4), 21 early (TL = 6, BL = 15), and 15 delayed implantations (TL = 11, BL = 4). All implant sites were simultaneously augmented. The prosthetic restorations were delivered 6 to 24 weeks after implant placement in the TL group and 10 to 14 weeks after implant placement in the BL group. Esthetic evaluation was performed after a mean period of 9.5 years for TL implants (range: 5.5 to 12.0) and 3.7 years for BL implants (range: 2.6 to 7.1). The overall PES was 8.49 (SD: 2.35) for TL implants and 9.29 (SD: 1.90) for BL implants (P = .37). Comparison of single parameters was between P = .24 and P = .83, indicating no statistically significant difference between the two implant types.
Within the limits of this study, it can be stated that both implant designs showed comparably satisfying esthetic results.
When failing front teeth are replaced by implants, vestibular bone deficiencies frequently require augmentation, even though the amount of missing alveolar volume may vary. The objective of this ...study was to analyze the horizontal alveolar ridge dimension after implant placement and simultaneous augmentation, and to compare it to the condition at the contralateral natural site.
Forty-eight patients with a failing maxillary incisor received an immediate or early implant (Straumann Bone Level), according to a randomized study protocol. The vestibular wall of the implant site was reconstructed and moderately overcontoured with bovine hydroxyapatite and a collagen membrane (BioOss, BioGide, Geistlich). Provisional restoration followed either immediately, or after a 6-week healing period. To investigate the vestibular volume 6 months after surgery, a plaster model of the maxilla was scanned with cone beam computed tomography (CBCT; Morita 3D) and evaluated using coDiagnostiX software (Dental Wings). Statistical analysis comprised one- and two-sample t tests.
The ridge volume was not significantly influenced by the treatment schedule. The vestibular segments had a mean ± SD volume of 207.9 ± 102.5 mm³ for the implant sites, and 202.1 ± 101.5 mm³ for the corresponding natural sites (P = .28). The difference in vestibular volume between implant sites and natural tooth sites was 10.4 ± 36.2 mm³ for immediate implantation, and 0.00 ± 31.1 mm³ for early implantation (P = .32). Comparing immediate and early restoration, a difference of 0.4 mm³ and 12.5 mm³ between the implant and contralateral site was found (P = .23).
Six months after treatment, no significant differences between the alveolar volumes at augmented implant sites and natural sites were found. Moderate buccal overcontouring may have been beneficial to achieve a symmetrical contour. Long-term follow-up investigation will document if the restored volume remains stable over time.
Intestinal fibrosis is a common feature of Crohn's disease and may appear as a stricture, stenosis, or intestinal obstruction. Fibrostenosing Crohn's disease leads to a significantly impaired quality ...of life in affected patients and constitutes a challenging treatment situation. In the absence of specific medical antifibrotic treatment options, endoscopic or surgical therapy approaches with their potential harmful side effects are frequently used. However, our understanding of mechanisms of fibrogenesis in general and specifically intestinal fibrosis has emerged. Progression of fibrosis in the liver, lung, or skin can be halted or even reversed, and possible treatment targets have been identified. In face of this observation and given the fact that fibrotic alterations in various organs of the human body share distinct core characteristics, this article aims to address whether reversibility of intestinal fibrosis may be conceivable and to highlight promising research avenues and therapies.
Intestinal fibrosis with stricture formation is a common feature of inflammatory bowel disease (IBD) and leads to a significantly impaired quality of life in affected patients, intestinal obstruction ...as well as to the need for surgical intervention. This constitutes a major treatment challenge. Key Messages: Fibrosis results from the response of gut tissue to the insult inflicted by chronic inflammation. Similarly to what occurs in other organs, the underlying fibrogenic mechanisms are complex and dynamic, involving multiple cell types, interrelated cellular events, and a large number of soluble factors. Owing to a breakdown of the epithelial barrier in IBD, luminal bacterial products leak into the interstitium and induce an innate immune response mediated by the activation of both immune and non-immune cells. Other environmental factors as well as chronic inflammation will certainly impact the quality and quantity of intestinal fibrosis. Finally, the composition of the intestinal extracellular matrix is dramatically altered in chronic gut inflammation and actively promotes fibrosis through its mechanical properties. The conventional view that intestinal fibrosis is an inevitable and irreversible process is gradually changing in light of an improved understanding of the cellular and molecular mechanisms that underline its pathogenesis. In addition, clinical observations in patients who undergo strictureplasty have shown that stricture formation is reversible.
Identification of the unique mechanisms of intestinal fibrogenesis should create a practical framework to target and block specific fibrogenic pathways, estimate the risk of fibrotic complications, permit the detection of early fibrotic changes and, eventually, allow the development of treatment methods customized to each patient's type and degree of intestinal fibrosis.
Patients with Crohn’s disease commonly develop ileal and less commonly colonic strictures, containing various degrees of inflammation and fibrosis. While predominantly inflammatory strictures may ...benefit from a medical anti-inflammatory treatment, predominantly fibrotic strictures currently require endoscopic balloon dilation or surgery. Therefore, differentiation of the main components of a stricturing lesion is key for defining the therapeutic management. The role of endoscopy to diagnose the nature of strictures is limited by the superficial inspection of the intestinal mucosa, the lack of depth of mucosal biopsies and by the risk of sampling error due to a heterogeneous distribution of inflammation and fibrosis within a stricturing lesion. These limitations may be in part overcome by cross-sectional imaging techniques such as ultrasound, CT and MRI, allowing for a full thickness evaluation of the bowel wall and associated abnormalities. This systematic literature review provides a comprehensive summary of currently used radiologic definitions of strictures. It discusses, by assessing only manuscripts with histopathology as a gold standard, the accuracy for diagnosis of the respective modalities as well as their capability to characterise strictures in terms of inflammation and fibrosis. Definitions for strictures on cross-sectional imaging are heterogeneous; however, accuracy for stricture diagnosis is very high. Although conventional cross-sectional imaging techniques have been reported to distinguish inflammation from fibrosis and grade their severity, they are not sufficiently accurate for use in routine clinical practice. Finally, we present recent consensus recommendations and highlight experimental techniques that may overcome the limitations of current technologies.
Crohn's disease (CD) is a chronic remitting and relapsing disease. Fibrostenosing complications such as intestinal strictures, stenosis and ultimately obstruction are some of its most common ...long-term complications. Despite recent advances in the pathophysiological understanding of CD and a significant improvement of anti-inflammatory therapeutics, medical therapy for stricturing CD is still inadequate. No specific anti-fibrotic therapy exists and the incidence rate of strictures has essentially remained unchanged. Therefore, the current therapy of established fibrotic strictures comprises mainly endoscopic dilation as well as surgical approaches. However, these treatment options are associated with major complications as well as high recurrence rates. Thus, a specific anti-fibrotic therapy for CD is urgently needed. Importantly, there is now a growing body of evidence for prevention as well as effective medical treatment of fibrotic diseases of other organs such as the skin, lung, kidney and liver. In face of the similarity of molecular mechanisms of fibrogenesis across these organs, translation of therapeutic approaches from other fibrotic diseases to the intestine appears to be a promising treatment strategy. In particular transforming growth factor beta (TGF-β) neutralization, selective tyrosine kinase inhibitors, blockade of components of the renin-angiotensin system, IL-13 inhibitors and mammalian target of rapamycin (mTOR) inhibitors have emerged as potential drug candidates for anti-fibrotic therapy and may retard progression or even reverse established intestinal fibrosis. However, major challenges have to be overcome in the translation of novel anti-fibrotics into intestinal fibrosis therapy, such as the development of appropriate biomarkers that predict the development and accurately monitor therapeutic responses. Future clinical studies are a prerequisite to evaluate the optimal timing for anti-fibrotic treatment approaches, to elucidate the best routes of application, and to evaluate the potential of drug candidates to reach the ultimate goal: the prevention or reversal of established fibrosis and strictures in CD patients.
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