Impact of long contact areas for the management of varying levels of interdental papilla loss on the perception of smile esthetics between dentists and laypersons in asymmetric and symmetric situations.

PURPOSE: To determine the effect of restorations with long contact areas for the management of interdental papilla deficiencies, in smile attractiveness among laypersons and dentists. MATERIAL AND METHODS: A full-portrait image was used to create a set of digitally modified images, simulating the management of various levels of interdental papilla loss. In a total of 48 modified images, single as well as multiple loss of interdental papilla among the anterior teeth, treated with a single or multiple restorations were simulated for unilateral and bilateral situations. Through a digital monitor 160 laypeople and dentists were asked to assess the attractiveness of each displayed image utilizing a visual-analog-scale. Multiple Wilcoxon-signed-rank tests followed by Mann-Whitney U tests were performed considering a significance level of 0.05. RESULTS: The management of an open gingival embrasure due to interdental papilla loss, by simulating the restoration of both central incisors led to a significantly higher mean smile attractiveness compared to the restoration of a single central incisor. Among the investigated regions, the management of open gingival embrasure in the area of central incisors using a restorative approach was perceived as the least esthetic (p < 0.05). CONCLUSIONS: Despite the restorative management of interdental papilla loss, with the establishment of longer contact areas for the reduction of open gingival embrasures, as the level of the interdental papilla loss is increased, facial esthetics are compromised. When a longer contact area is accomplished through a single restoration, asymmetry among the teeth can be induced, especially in the region of the central incisors.

Proposal regarding potential causes related to certain complications with dental implants and adjacent natural teeth: Physics applied to prosthodontics.

PURPOSE: Complications can and do occur with implants and their restorations with causes having been proposed for some single implant complications but not for others. METHODS: A review of pertinent literature was conducted. A PubMed search of vibration, movement, and dentistry had 175 citations, while stress waves, movement, and dentistry had zero citations as did stress waves, movement. This paper discusses the physics of vibration, elastic and inelastic collision, and stress waves as potentially causative factors related to clinical complications. RESULTS: Multiple potential causes for interproximal contact loss have been presented, but it has not been fully understood. Likewise, theories have been suggested regarding the intrusion of natural teeth when they are connected to an implant as part of a fixed partial denture as well as intrusion when a tooth is located between adjacent implants, but the process of intrusion, and resultant extrusion, is not fully understood. A third complication with single implants and their crowns is abutment screw loosening with several of the clinical characteristics having been discussed but without determining the underlying process(es). CONCLUSIONS: Interproximal contact loss, natural tooth intrusion, and abutment screw loosening are common complications that occur with implant retained restorations. Occlusion is a significant confounding variable. The hypothesis is that vibration, or possibly stress waves, generated from occlusal impact forces on implant crowns and transmitted to adjacent teeth, are the causative factors in these events. Since occlusion appears to play a role in these complications, it is recommended that occlusal contacts provide centralized stability on implant crowns and not be located on any inclined surfaces that transmit lateral forces that could be transmitted to an adjacent tooth and cause interproximal contact loss or intrusion. The intensity, form, and location of proximal contacts between a natural tooth located between adjacent single implant crowns seem to play a role in the intrusion of the natural tooth. Currently, there is a lack of information about the underlying mechanisms related to these occurrences and research is needed to define any confounding variables.

A decision-making tree for evaluating an esthetically compromised single dental implant.

OBJECTIVE: To develop a comprehensive decision-making tree for evaluating mid-facial peri-implant soft tissue dehiscence in the esthetic zone and provide a systematic approach for assessing various clinical case scenarios, determining appropriate treatment strategies, and considering factors such as the need for soft tissue augmentation, prosthetic changes, or implant removal. CLINICAL CONSIDERATIONS: This clinical decision tree illustrates numerous case scenarios with various esthetic complications around an esthetically compromised, but clinically healthy single implant and provides clinicians with possible solutions as a predictable map for horizontal and vertical soft tissue augmentation in order to manage different clinical circumstances. According to current evidence, the key to treating such esthetic complications is the use of an adequate pre-surgical prosthetic interdisciplinary approach with proper surgical techniques in order to optimize soft tissue dimensions and create better esthetic results. This may be accomplished through a purely surgical, combination of surgical and prosthetic, or purely prosthetic approaches. CONCLUSIONS: The present report describes a series of successfully treated peri-implant esthetic complication cases in accordance with the decision-making tree that the authors recommend in order to achieve better long-term esthetic outcomes. CLINICAL SIGNIFICANCE: The combination of adequate pre-surgical prosthetic interdisciplinary collaboration and proper surgical technique is critical in the optimization of sufficient soft tissue dimensions and contributes to a more highly esthetic result. This study demonstrates a clinical decision-making tree to provide comprehensive, effective therapy of an esthetically compromised dental implant by using one of the following approaches: purely prosthetic, purely surgical, or a combination of surgical and prosthetic with or without abutment removal.

A comparative analysis of dual-axis implants placed into maxillary anterior extraction sockets versus virtual planning with uniaxial implants: A simulated cone beam computed tomography study of implant length and diameter.

OBJECTIVE: The biaxial nature of the anterior maxilla poses a surgical and restorative challenge in implant dentistry. The present study sought to investigate the apical socket perforation rate (ASPR) from a simulated uniaxial implant placement and to determine the effect of implant length and diameter on ASPR when a uniaxial implant was placed compared with the orientation of the pre-existing dual-axis implant. MATERIAL AND METHOD: Cone beam computed tomography (CBCT) scans from the database of three private practices were searched for patients who received dual-axis implants within the esthetic zone in immediate tooth replacement therapy. A uniaxial implant was virtually placed using the pre-existing screw access channel of the dual-axis implant as a reference. The closest length and diameter were selected for the simulated implant. ASPR by the uniaxial implant was recorded. In addition, the affordable maximum length of a corresponding uniaxial implant that would avoid apical socket perforation was measured. RESULT: Eighty-one patients with a total of 101 dual-axis dental implants were selected for analysis. A simulated virtual surgical planning with uniaxial implants revealed high ASPR (48.51%). When the length of the uniaxial implant was reduced to 11 and 9 mm, ASPR was decreased to 41.58% and 20.79%, respectively. CONCLUSION: Dual-axis implant design effectively evades anatomical challenges in the anterior maxilla (esthetic zone). Considering the current evidence, efforts should be made to carefully consider the angular disparity between the extraction socket-alveolus complex and the future restorative emergence so that a harmonious biologic-esthetic result may be more predictably and consistently obtained.

Selective Serotonin Reuptake Inhibitors and Dental Implant Failure: A Systematic Review and Meta-Analysis.

Selective serotonin reuptake inhibitors (SSRI) are commonly prescribed to treat mental health disorders, and previously published literature, although scarce, has shown a significant association between SSRI use and dental implant failure. This systematic review and meta-analysis aimed to examine whether such an association exists and, if so, to determine its strength. Reviewers performed an extensive search of the literature, last accessed in June 2022 in PubMed/Medline, Embase, and Cochrane databases using MeSH terms. Retrospective and prospective observational cohort and experimental studies evaluating the role of SSRI on dental implant failure among individuals ≥18 years of age, with a minimum follow-up of 6 months after implant placement, were deemed eligible. The search yielded a total of 6 eligible studies, all retrospective cohorts. Statistical analyses were performed using the statistical software R 4.1.3. Results showed higher implant failure rates among SSRI users vs non-SSRI users at both the patient level (5.6%-19.6% vs 1.9%-8.0%) and the implant level (5.6%-12.5% vs 1.9%-5.8%). The pooled relative risk (RR) of implant failure was more than double among SSRI users at the patient level (pooled RR: 2.44, 95% confidence interval [CI]: 1.68-3.55, P < .01) and at the implant level (pooled RR: 2.34, 95% CI: 1.74-3.15, P < .01) compared with non-SSRI users. DerSimonian and Laird estimates showed homogeneity of the studies (I2 = 0%, P > .05), and funnel plots and Egger's test determined no publication bias across all selected studies at both patient and implant levels. In conclusion, SSRI use is significantly associated with higher implant failure. Providers should be aware of this association and educate patients on the risk of implant therapy when obtaining informed consent.

The effect of implant macrogeometry in immediate tooth replacement therapy: A case series.

The concept of immediate tooth replacement therapy (ITRT) in the esthetic zone has become a viable treatment modality and widely accepted in clinical practice. However, achieving adequate primary stability that enables immediate provisional restoration and desirable space for bone-grafting with conventional tapered body implant designs is challenging. The macro-hybrid implant design with a prosthetic angle correction and body-shift feature in a singular form provides not only greater primary stability of a wider diameter implant but also circumferential gap distance both facially and interproximally preserve the labial bone plate and interdental attachment apparatus of the adjacent natural teeth thereby maintaining the interdental papilla. The present clinical series exemplifies the clinical advantages of this inverted body-shift implant design in ITRT in various clinical scenarios in (1) single tooth replacement in a Type 1 intact socket with a thin periodontal phenotype, (2) single tooth replacement in a Type 2 socket with a dentoalveolar dehiscence of the labial bone plate, and (3) multiple adjacent teeth replacement of two maxillary central incisor. CLINICAL SIGNIFICANCE: The macro-hybrid design implant with a prosthetic angle correction and body-shift feature in a singular form provides greater midfacial gap distance as well as tooth-to-implant distance to preserve the interdental attachment of the adjacent natural teeth thereby leaving the interdental papilla undisturbed, without sacrificing higher primary stability afforded by larger diameter implants.

Interdisciplinary management of recession defects on maxillary single tooth implants: Diagnosis and treatment strategies.

OBJECTIVE: One of the most common complications with dental implants placed in the smile zone is the development of mid-facial recession, creating an undesirable esthetic result. When deciding how to remediate these clinical scenarios, the question becomes whether it may be feasible to save the problematic implant or if it is more predictable to remove the implant and start all over again. However, patients may be invested emotionally, physically, and financially in the implant and remediation may be a viable option depending on the diagnosis of the specific issues at hand and multi-disciplinary clinical execution. CLINICAL SIGNIFICANCE: What is crucial to understand in order to remediate these cases is answering four separate criteria: (1) is the implant in a restorable position, (2) is the implant healthy, (3) is the implant placed at an adequate depth, and (4) are components available to restore the implant. CONCLUSIONS: Two different clinical reports are presented that demonstrate various treatment remedies when saving implants in the esthetic zone.

When to save or remove implants in the smile zone: A clinical report of maxillary lateral incisor implants in malposition.

OBJECTIVE: The following is a clinical report addressing when to save or remove implants with esthetic deficiencies in the smile zone as well as the sequence and timing of interdisciplinary treatment. CLINICAL CONSIDERATIONS: Key factors in the decision-making process in treating implants in malposition are whether the implants are (1) in a reasonable restorative position, (2) free of disease, and (3) placed with adequate depth. This clinical report encompassed periodontal corrective surgery, non-surgical soft tissue sculpting through subgingival crown contour, material selection for definitive restorations, and cementation techniques for cement-retained restorations. CLINICAL SIGNIFICANCE: Knowledge and understanding of interdisciplinary treatment planning, sequencing, and respective techniques that can be implemented when confronting implants in malposition in the smile zone will allow the interdisciplinary team to achieve the desired esthetic restorative result.

The Relationships Between Tooth-Supported Fixed Dental Prostheses and Restorations and the Periodontium.

PURPOSE: To search the literature and to critically evaluate the findings on the periodontal outcomes of restorations and tooth-supported fixed prostheses. MATERIALS AND METHODS: PubMed was searched according to a systematic methodology, previously reported, but updated to include a larger database. Filters applied were: Case reports, clinical trial, review, guideline, randomized controlled trial, meta-analysis, systematic reviews, and English. A narrative review was then synthesized to discuss periodontal outcomes related to restorations and tooth-supported fixed prostheses. Relevant data was organized into four sections: Direct restorations, indirect restorations, biologic width or supracrestal tissue attachment and tooth preparation/finish line design. RESULTS: While increased gingival index, bleeding on probing, probing depth and clinical attachment loss have been associated with subgingival restorations, intracrevicular margins do not cause periodontal diseases. Inflammation and bone loss occur, for both direct and indirect restorations, only with large overhangs. Different restorative materials are associated with different clinical responses when placed in the gingival sulcus or within the epithelial and connective tissue attachments. When the connective tissue attachment is removed, histological changes occur causing its apical shift and subsequent re-establishment. Gingival displacement during impression procedures can cause gingival recession. Emergence profile can have a range of values, not associated with periodontal diseases. Periodontal response appears to be clinically not different when compared among different finish line designs. CONCLUSIONS: Contemporary procedures and materials used for the placement and fabrication of tooth-supported restorations and fixed prostheses are compatible with periodontal health when adequate patient education and motivation in self-performed oral hygiene are present. Periodontal diagnostic criteria should be thoroughly reviewed before fixed restorative treatments are planned and executed.

Parenchymal and stromal tissue regeneration of tooth organ by pivotal signals reinstated in decellularized matrix.

Cells are transplanted to regenerate an organs' parenchyma, but how transplanted parenchymal cells induce stromal regeneration is elusive. Despite the common use of a decellularized matrix, little is known as to the pivotal signals that must be restored for tissue or organ regeneration. We report that Alx3, a developmentally important gene, orchestrated adult parenchymal and stromal regeneration by directly transactivating Wnt3a and vascular endothelial growth factor. In contrast to the modest parenchyma formed by native adult progenitors, Alx3-restored cells in decellularized scaffolds not only produced vascularized stroma that involved vascular endothelial growth factor signalling, but also parenchymal dentin via the Wnt/ß-catenin pathway. In an orthotopic large-animal model following parenchyma and stroma ablation, Wnt3a-recruited endogenous cells regenerated neurovascular stroma and differentiated into parenchymal odontoblast-like cells that extended the processes into newly formed dentin with a structure-mechanical equivalency to native dentin. Thus, the Alx3-Wnt3a axis enables postnatal progenitors with a modest innate regenerative capacity to regenerate adult tissues. Depleted signals in the decellularized matrix may be reinstated by a developmentally pivotal gene or corresponding protein.