Supracrestal Tissue Attachment Research Articles

Biologic Width Following Different Crown Lengthening Procedures: A Six-Month Follow-Up Study.

One of the important things to preserve during crown lengthening is the biologic width (BW), recently called supracrestal tissue attachment. A healthy periodontium with adequate BW is very essential for the success of restored teeth. There are various techniques to perform crown lengthening procedures. Most of the studies have focused on assessing the changes in the position of the marginal gingiva and bone as outcome parameters rather than BW. Also, most of the research was done on animal models. The purpose of this study was to assess the periodontal tissue changes at three months and six months following two different surgical crown lengthening procedures. Sixty mandibular first molars among 60 patients that required surgical crown lengthening were enrolled in the study and subjected to two different procedures, gingivectomy (Group I; n=30) and apically positioned flap with ostectomy (Group II; n=30). The following parameters were recorded at baseline, three months, and six months, position of free gingival margin (FGM), probing depth (PD), relative attachment level (RAL), bone level (BL), and BW. These measurements were made at three sites in every patient: treated tooth sites (TT), adjacent tooth's adjacent sites (AD), and adjacent tooth's non-adjacent sites (NAD). The data was then subjected to statistical analysis using SPSS software (Version 20.0). Statistical significance was set to p<0.05. When groups I and II were compared at three and six months, there was no statistical difference in terms of position of FGM, PD, and RAL (p>0.05). When BW was compared between the two groups at three and six months, group II showed better reestablishment of BW at any given time period and was statistically significant (p<0.05). Following surgical crown lengthening, the bone level was shifted apically and allowed for the reestablishment of BW. At six months of follow-up, the apically positioned flap with ostectomy was superior in restoring the BWcompared to gingivectomy.

LASER-ASSISTED CROWN LENGTHENING: CLINICAL EFFICACY AND ADVANTAGES OVER CONVENTIONAL TECHNIQUES (SYSTEMATIC REVIEW)

Introduction: Crown lengthening is a widely recognized dental procedure with both aesthetic and functional purposes. It involves the reduction of periodontal hard and soft tissues to obtain supracrestal tooth length, resulting in longer clinical crowns and adequate supracrestal tissue attachment. Laser therapy has emerged as a promising alternative that is currently developing in the field of periodontics and offers several advantages. This review aims to synthesize the current research on the clinical efficacy of laser-assisted crown lengthening procedures and highlight their advantages over conventional methods. Review: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search was conducted in electronic databases PubMed, Scopus, Embase, and Google Scholar for human studies published from 2017 to April 2023. Out of 213 identified and screened studies, three original articles were included in the analysis. Two clinical trial studies used Er,Cr:YSGG while one study used Er:YAG for crown lengthening procedures involving gingiva and alveolar bone reduction, with a 3-month follow-up period. Compared to conventional crown lengthening, the laser-assisted approach showed comparable increases in clinical crown length. However, the laser-assisted group demonstrated better gingival margin stability, improved soft tissue healing, and minimal damage to adjacent tissues. Furthermore, there was a statistically significant lower bacterial load and less post-surgery pain with laser-assisted crown lengthening compared to the conventional method. Conclusion: In cases where both gingival and bone reduction are required, laser-assisted crown lengthening using Er,Cr:YSGG and Er:YAG can be considered a minimally invasive alternative with several advantages over conventional procedures.

Biological shaping as a conservative alternative for crown lengthening: A review.

The perio-restorative approach to maintaining supracrestal tissue attachment (STA; formerly known as biologic width) is a fundamental goal in modern dentistry. This article aims to review the clinical impact of biologic shaping (BS) as an innovative alternative to traditional crown lengthening procedures, reflecting over two decades of clinical experience. As a review paper, it is crucial to highlight that BS stands as a unique approach designed to optimize STA while emphasizing minimal to no removal of supporting bone. The review spans over two decades, consistently demonstrating clinical efficacy and predictability. Remarkably, BS focuses on addressing issues such as root concavities, developmental grooves, irregularities, furcation lips, and CEJ offering a remarkable level of clinical precision. The reviewed literature underscores that BS has consistently achieved substantial clinical success in fulfilling its objectives. This method presents a biologically sound alternative to traditional crown lengthening, placing a strong emphasis on the preservation of essential bone tissue and the establishment of durable STA. The results suggest that BS is a logical and biologically driven approach for maintaining STA, making it a promising alternative to traditional crown lengthening. The method offers a predictable and reproducible way to preserve bone tissue while achieving durable STA. This innovation holds great promise in the field of periodontal and restorative dentistry.

Restoration of Teeth with Severely Compromised Tooth Structure using Digital Planning Combined with Orthodontic Magnetic Extrusion—A Report of 2 Cases

This report outlines 2 digitally planned cases in which the teeth underwent magnetic extrusion to preserve the supracrestal tissue attachment and regain the ferrule, followed by their restoration. Case 1: A 42-year-old man with the chief concern of a fractured right maxillary second premolar. Following the completion of root canal treatment, the remaining tooth structure was insufficient to create a ferrule for tooth restoration. For this scenario, a rapid magnetic extrusion technique was performed on tooth #4 to obtain an approximate 3-mm ferrule. The condition of both the dentition and the restorative margin was acceptable 18 months following treatment. Case 2: A 62-year-old man with the chief complaint of mobility on both sides of the maxillary arch in relation to a tooth-supported fixed partial denture (FPD). Following removal of the FPD, multiple extractions were carried out and tooth #6 was subjected to magnetic extrusion in 3 stages to a maximum of 4 mm to obtain a ferrule. At the 18-month and 3-year follow-up appointments, the tooth had no symptoms and the gingiva around the restorations had optimal architecture and margins. The 3-dimensional digital planning was helpful in precisely positioning the magnets within the tooth and the provisional restorations to facilitate axial extrusion. The extruded teeth were restored with zirconia crowns in both cases. The beneficial outcomes observed from these cases provides evidence that the integration of digital planning and magnetic extrusion holds promise as a method for reconstructing teeth with crowns that are significantly compromised.

Digital assessment of supracrestal tissue attachment and its correlation with dentogingival components.

The aim of this study is to measure, in vivo, the supracrestal tissue attachment dimensions (STADs) by means of a noninvasive digital method and to investigate the association between STADs and gingival thickness (GT), tooth position, tooth length, tooth width, keratinized tissue width (KTW), buccal bone thickness (BBT), and bone crest (BC) level. Nineteen periodontally healthy subjects who previously received full mouth periodontal charting, cone beam computed tomography, and intraoral scan for the purpose of implant planning were included in the study. A digital imaging software was used for the superimposition of Digital Imaging and Communications in Medicine and stereolithography files, along with hard and soft tissue measurements. Pearson's correlation and ANOVA statistical analyses were used to investigate potential trends between STADs and other dentogingival components. A total of 203 teeth were assessed, with an average STADs of 2.05mm (±0.99mm). STADs were larger in mandibular than maxillary teeth (p-value <0.001) and decreased from anterior to posterior teeth. STADs exhibited an inverse relationship with BBTs and GTs (p-value <0.001) and the KTW (p-value=0.05). Positive correlations were found between GT and BBT (p-value <0.001), whereas both were negatively correlated with the distance between the cementoenamel junction and BC (p-values 0.019 and 0.006, respectively) and positively correlated with KTW (p-value <0.001). This study highlighted the dynamic nature of STA relative to tooth position. Additionally, it explored the intricate relationships of STADs with various dentogingival components. To the best of the authors' knowledge, this study represents the first application of CBCTs, intraoral scans, and clinical probe depths for noninvasive supracrestal tissue attachment measurements. This study advocates for a personalized assessment of supracrestal attachments, incorporating tooth position and other dentogingival components. The study emphasizes the importance for practitioners to consider the specific patient gingival phenotypes during restorative or surgical planning to avoid adverse outcomes.

Retrospective Study on 57 Direct Interproximal Restorations with Supracrestal Tissue Attachment Violation: Follow-Up Between 10 and 23 Years.

Fifty-seven interproximal restorations invading the supracrestal tissue attachment were evaluated over a mean period of 15 years (10-23 years) in terms of crestal bone loss. The distance from the cavity margin to the bone was measured at T0 and controlled using X-rays and a measurable landmark. The mean bone loss in the vertical dimension was 0.46 mm, with a 96.49% survival rate. Smoking habits (p = 0.02) and tooth type (p = 0.03) significantly affected the bone loss. The proposed technique could help the clinician in adopting a minimally invasive approach in the treatment of heavily compromised teeth. Future research with rigorous study designs would be interesting to guide the clinical decision making.

Hard and soft tissue healing around implants with Ag coating: An experimental study in dogs

Introduction The purpose of this randomized controlled canine experimental study was to evaluate peri‑implant hard and soft tissue healing around implants with silver coating.Methods All mandibular premolars and molars of five male beagle dogs were extracted. 25 test and 25 control implants were randomly installed and connected with the healing abutments. After 2 and 4 month healing period, implants with soft and hard tissues were obtained for histologic and histomorphometric analysis.Results In mesio-distal sections, supracrestal tissue attachment dimensions were 4.03±0.48 mm and 4.25±0.66 mm for test and 4.34±0.6 mm and 5.21±0.72 mm for control implants at 2 and 4 month healing time. The respective crestal bone loss values were 1.10±0.69 mm and 0.74±0.67 mm for test and 1.13±0.48 mm and 1.49±0.65 mm for control implants. The differences were statistically significant only in the 4-month healing period. In buccolingual sections, supracrestal tissue attachment height at 2 and 4 month healing periods were 4.09±0.64 mm and 4.5±0.8 mm for test implants and 4.17±0.76 mm and 4.48±0.76 mm for control implants. The respective mean values for crestal bone loss were 1.31±0.6 mm and 1.02±0.58 mm for test implants, and 1.28±0.61 mm and 1.29±0.69 mm for control implants. No statistical significant differences were recorded, apart from the height of connective tissue at the 2 month healing group. No significant difference in terms of BIC between implants or healing periods was recorded.Conclusions The Ag implant coating resulted in smaller supracrestal tissue attachment dimensions and less bone loss. Within the limits of a canine study, prevention of crestal bone loss along with the effectiveness of Ag antimicrobial properties in dental implantology is demonstrated.

Structurally compromised teeth. Part I: Clinical considerations and novel classification proposal.

A comprehensive classification of structurally compromised teeth (SCT) was introduced. Dental injuries or operative mismanagement undermine the structural integrity of the tooth abutment, reducing its biomechanical strength and rendering restorative procedures challenging. To standardize the overall pre-operative evaluations and determine the biological and mechanical features, a classification of the coronal and cervical tooth defects, as well as an attentive analysis of the most apical location of the residual cervical tooth structure along the whole perimeter and the most coronal location of the bucco/lingual residual structure was presented. Considering the residual cervical structure, five possible clinical scenarios were individuated with respect to the gingival margin, gingival sulcus, supracrestal tissue attachment and bone crest (BC). The latter prevents the isolation procedures rendering the adhesive restorations unfeasible. Instead, the location of the most apical portion of residual cervical structure within subgingival/intrasulcular depth (>1.5 mm above BC) can be considered restorable. This classification is threefold: to enclose all the possible clinically encountered tooth defects, to identify the apical problems of SCT to appropriately manage the perio-restorative interfaces, and to evaluate the tooth resistance capacity of SCT, as to plan and perform the most adequate biomechanical restorative approach. The present classification is proposed to provide a complete perspective of structurally compromised teeth to standardize the biologic and biomechanical evaluations during planning of restorative procedures.

Fixed and on-demand regimens of acetaminophen in periodontal surgery

Aim: to evaluate the clinical efficacy of an acetaminophen analgesic by comparing its prescription in fixed versus ondemand schedules after periodontal surgery. The hypothesis of the study was that the fixed regimen would be more effective than the on-demand regimen for postoperative analgesics following periodontal surgery. Methods: An open randomized clinical trial was conducted. The 68 patients who needed total flap surgery to restore supracrestal tissue attachment or surgical treatment of periodontitis were randomized”. Visual Analogue Scale was used to assess pain. The fixed group (n = 34) received 500 mg of acetaminophen every 4 hours for 2 days. The on-demand group (n = 34) was instructed to use the acetaminophen “as needed,” at intervals of no less than 4 hours between doses. Ibuprofen was the rescue medication for both groups. Pain scores and medication use were recorded 2, 6, 12, 24 and 48 hours after the surgical procedure. The study was registered at the Brazilian Registry of Clinical Trials under RBR-7wv259. Results: The two groups did not differ in relation to the frequency or the intensity of pain in a 48-hour period (n=20 in the fixed group, and n=22 in the on-demand group), or even in the intention-to-treat (n=34 in each group). Individuals who experienced moderate to severe pain used rescue medication more frequently in both groups. No adverse events were reported. Conclusion: Both regimens were effective in controlling postoperative pain after periodontal surgery.

Digital orthodontic extrusion system for complex crown-root fracture of anterior teeth: A technique report

Patients with traumatic dental injuries commonly present in clinical practice with complex crown-root fractures. Prosthodontic treatment of such patients may be unsuccessful because of the violation of the supracrestal tissue attachment, making their management challenging. Minor tooth movement is an effective solution to extruding the residual root but may require referral to an orthodontist. The purpose of this technique was to present a digital orthodontic system including a 3-dimensional virtual patient technique, a computer-aided design and computer-aided manufacture (CAD-CAM) resin facial veneer-retained pontic, and a zirconia post as an orthodontic appliance for tooth extrusion in the esthetic zone. This veneered pontic may also serve as an interim prothesis. The appliance provides a precise design for the direction and extent of orthodontic extrusion.

Supracrestal tissue attachment: an update

Supracrestal tissue attachment (STA) is a relatively new term that was introduced in 2017 following the World Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions, co-sponsored by the American Academy of Periodontology (AAP) and the European Federation of Periodontology (EFP), which included expert participants from all over the world. It has replaced the term biological width, and refers to the junctional epithelium and supracrestal connective tissue. This article provides an updated review of the anatomy of STA, highlights the negative effects of violation and discusses its clinical relevance in restorative dentistry, including the use of crown lengthening. The impact of implants on STA is highlighted, and a summary of the relevance of STA in implant dentistry is also discussed. CPD/Clinical Relevance: To allow dental practitioners to have more confidence providing adequate function, comfort, and aesthetics in the dentition, while maintaining periodontal health.

Forced orthodontic extrusion for an apparently hopeless anterior tooth by using a simplified approach

When restoring severely compromised teeth, respecting the supracrestal tissue attachment and retaining the most coronal and radicular tooth structure is essential to achieving a sufficient ferrule. Forced orthodontic extrusion is a minimally invasive method that allows hard- and soft-tissue conservation. This article describes the treatment of a severely damaged maxillary central incisor that was managed by using a simplified orthodontic extrusion method with intracoronal elastic and metal ligatures applied through a palatal bar and followed by the biologically oriented preparation technique (BOPT). This orthodontic procedure reduces a forward clockwise advance during vertical extrusion, thus maintaining the buccal bone plate.

Clinical Considerations in Orthodontically Forced Eruption for Restorative Purposes.

For restorations on teeth involving invasion of the supracrestal tissue attachment (biological width), as well as for lack of ferrule effect, crown lengthening is required for long-term periodontal health and success of the restoration. In the same fashion, site development is often necessary prior to implant placement in order to provide optimal peri-implant soft and hard tissue architecture conducive to future esthetics and function. Orthodontic extrusion, also known as forced eruption, has been developed and employed clinically to serve the purposes of increasing the clinical crown length, correcting the periodontal defect, and developing the implant site. In order to provide comprehensive guidance on the clinical usage of this technique and maximize the outcome for patients who receive the dental restoration, the currently available literatures were summarized and discussed in the current review. Compared to traditional crown lengthening surgery, forced eruption holds advantages of preserving supporting bone, providing improved esthetics, limiting the involvement of adjacent teeth, and decreasing the negative impact on crown-to-root ratio compared to the traditional resective approach. As a non-invasive and natural technique capable of increasing the available volume of bone and soft tissue, forced eruption is also an attractive and promising option for implant site development. Both fixed and removable appliances can be used to achieve the desired extrusion, but patient compliance is a primary limiting factor for the utilization of removable appliances. In summary, forced eruption is a valuable treatment adjunct for patients requiring crown lengthening or implant restorations. Nonetheless, comprehensive evaluation and treatment planning are required for appropriate case selection based upon the known indications and contraindications for each purpose; major contraindications include inflammation, ankylosis, hypercementosis, vertical root fracture, and root proximity. Further studies are necessary to elucidate the long-term stability of orthodontically extruded teeth and the supporting bone and soft tissue that followed them.

Periodontal and Periapical Outcomes of Surgical Extrusion: A Prospective Clinical Volumetric Study

IntroductionOutcome predictors for the restoration of endodontically treated teeth mainly include cavity wall integrity and the presence of a 1.5–2 mm ferrule. However, in some clinical situations, the aforementioned predictors cannot be achieved. Three different techniques have been proposed to obtain an adequate ferrule respecting the supracrestal tissue attachment: surgical crown lengthening, orthodontic forced eruption, and surgical extrusion. There are little published prospective data evaluating periodontal changes after surgical extrusion. Therefore, the aims of this study were to report the outcome of surgical extrusion in single-rooted teeth, to digitally evaluate soft tissue volumetric changes after surgical extrusion, and to observe patient satisfaction regarding the treatment after a minimum of 1 year. MethodsThis prospective clinical study was performed between 2017 and 2020. Thirteen patients referred for surgical extrusion met the following inclusion criteria: nonsmokers; systemically healthy with at least 1 straight, single-rooted tooth with an insufficient ferrule; a favorable tooth crown-to-root ratio, and no periodontal pathology. Preoperative clinical variables included patient age, sex and phenotype, tooth number, tooth mobility, crown-to-root ratio, gingival index (GI), probing pocket depths at 6 sites, bleeding on probing (BOP), and mesial and distal interproximal papillae volume. Surgical extrusion was performed by a single operator who completed the root canal treatment/retreatment and restored the teeth with a crown. One year later, all patients were controlled, and the following variables were recorded: tooth mobility, crown-to-root ratio, GI, pocket depth, BOP, interproximal papillae aspect, soft tissue rebound, periapical healing, marginal bone loss, and patient-reported outcome measures of the treatment. All variables were analyzed using a descriptive method (mean, %). The Wilcoxon test was used to evaluate pre- and postoperative clinical parameters at a significance level of .05. ResultsAt a mean follow-up period of 18.8 months, no teeth were extracted. Compared with preoperative GI and BOP, a significant reduction was observed at 1 year after surgery. Likewise, no significant differences in probing depths were shown, and only 1 tooth presented a type 2 mobility. The mean soft tissue rebound was −0.46 ± 0.69 mm. Overall, no significant interproximal papillae height loss was observed.Apical lesions were completely healed after surgery. The tooth crown-to-root ratio was favorable in all cases before extrusion, whereas in 3 cases it was appropriate (1 = 1), and only 1 case presented >25% of marginal bone loss during the follow-up period. The reported success rate was 92.3%, and patients were generally satisfied with the outcome. ConclusionsSurgical extrusion of single-rooted teeth was successful with minimal or no soft tissue loss, and patients were satisfied with the surgical procedure and the esthetic result.

Periodontal Analysis of Teeth with Biological Space Invasion submitted to Root Extrusion and Prosthetic Rehabilitation: Literature Review

Aim: The purpose of this literature review was to identify whether root traction may maintain the periodontal health of teeth with invasion of supracrestal tissue attachment and prosthetically rehabilitated. Materials and Methods: A literature review was conducted, in which the periodontal effects of root traction provided on the ability to maintain teeth with invasion of supracrestal tissue attachment and prosthetically rehabilitated were searched in the electronic databases Scopus, PubMed, Web of Science, EMBASE, Scielo and Cochrane using the Mesh descriptors "orthodontic extrusions", "forced eruption" and "crown lengthening". The inclusion criteria considered studies published in English or Spanish that presented the relationship between root traction and the effect on periodontal health in prosthetically rehabilitated teeth. After collection of articles, they were evaluated by three reviewers, who selected the studies according to their relevance according to criteria as type of study, root traction present, rehabilitation with single fixed prosthesis and period of clinical follow-up. Results: A total of 644 references were identified and after exclusion according to eligibility criteria, 33 papers covered all parameters adopted and were included in the qualitative analysis. Satisfactory prosthetic rehabilitation, associated with periodontal health after root traction, could be observed in all studies, notably with variation only in the follow-up time observed up to the first six months, 1, 2, 3 and up to 4 years. Conclusions: Root traction is a conservative and effective tool in the maintenance of periodontal health in teeth with invasion of supracrestal tissue attachment and prosthetically rehabilitated.

Orthodontic Extrusion vs. Surgical Extrusion to Rehabilitate Severely Damaged Teeth: A Literature Review.

The need to rehabilitate severely compromised teeth is frequent in daily clinical practice. Tooth extraction and replacement with dental implant represents a common treatment choice. However, the survival rate for implants is inferior to teeth, even if severely damaged but properly treated. In order to reestablish a physiological supracrestal tissue attachment of damaged teeth and to arrange an efficient ferrule effect, three options can be considered: crown lengthening, orthodontic extrusion and surgical extrusion. Crown lengthening is considered an invasive technique that causes the removal of part of the bony support, while both orthodontic and surgical extrusion can avoid this inconvenience and can be used successfully in the treatment of severely damaged teeth. The aim of the present narrative review is to compare advantages, disadvantages, time of therapy required, contraindications and complications of both techniques.

Treatment of Teeth with Insufficient Clinical Crown. Part 1: One-Year Clinical Outcomes of a Minimally Invasive Crown-Lengthening Approach.

This study describes a clinical strategy based on a flowchart developed to facilitate the treatment of teeth with a severely compromised clinical crown. A group of 168 teeth in 126 patients required periodontal surgery and received a minimally invasive crown-lengthening procedure with the aim to reach a minimal supracrestal tissue attachment width of 2.5 mm, including a free space between the cervical margin of the restoration and the bottom of the sulcus. Surgery was performed with the aid of an operating microscope and microsurgical instruments, trying to reduce bone surgery and invasiveness as much as possible. An average postsurgical radiographic bone resection of 1 ± 0.6 mm was measured. Endodontic treatment was necessary in 73 teeth, re-treatment in 51. Most of the teeth (124 in 94 patients) received a full crown, while the remaining 44 received a direct (24 teeth) or an indirect (20 teeth) reconstruction. Six teeth were orthodontically extruded before surgery. The 1-year average pocket depth at the treated units was 2.5 ± 0.5 mm, resulting in a reduction of 0.7 ± 0.9 mm compared to the preoperative measurement (P < .0001). Bleeding on probing was detected in 19 sites (11.3%) and was significantly reduced from the preoperative condition (57 sites, 33.9%). The distance between the apical margin of the restoration and the gingival margin was 0.2 ± 0.4 mm (range: 0 to 1 mm); clinical attachment level was 2.7 ± 0.6 mm. A clinical approach based on minimally invasive crown lengthening with minimal or no ostectomy and high-quality restorative dentistry resulted in healthy periodontal and dental condition of all the treated units at the 1-year follow-up.

Soft Tissue Interface with Various Kinds of Implant Abutment Materials.

Various materials, such as titanium, zirconia and platinum-gold (Pt-Au) alloy, have been utilized for dental implant trans-mucosal parts. However, biological understanding of soft tissue reaction toward these materials is limited. The aim of this study was to compare the response of cell lines and soft tissue to titanium, zirconia and Pt-Au substrata. The surface hydroxyl groups and protein adsorption capacities of the substrata were measured. Next, gingival epithelial-like cells (Sa3) and fibroblastic cells (NIH3T3) were cultured on the materials, and initial cell attachment was measured. Immuno-fluorescent staining of cell adhesion molecules and cytoskeletal proteins was also performed. In the rat model, experimental implants constructed from various materials were inserted into the maxillary tooth extraction socket and the soft tissue was examined histologically and immunohistochemically. No significant differences among the materials were observed regarding the amount of surface hydroxyl groups and protein adsorption capacity. Significantly fewer cells of Sa3 and NIH3T3 adhered to the Pt-Au alloy compared to the other materials. The expression of cell adhesion molecules and a well-developed cytoskeleton was observed, both Sa3 and NIH3T3 on each material. In an animal model, soft tissue with supracrestal tissue attachment was observed around each material. Laminin-5 immuno-reactivity was seen in epithelia on both titanium and zirconia, but only in the bottom of epithelia on Pt-Au alloy. In conclusion, both titanium and zirconia, but not Pt-Au alloy, displayed excellent cell adhesion properties.

Periodontal response to a tricalcium silicate material or resin composite placed in close contact to the supracrestal tissue attachment: a histomorphometric comparative study.

Subgingival dental restorations and periodontal health have been studied for many years; however, there is a low histological evidence on the behavior of new materials in the supracrestal tissue attachment. The aim of this study is to analyze the periodontal response when a tricalcium silicate material (TSM) or composite margin restorations is placed to 0.5 mm and 1.5 mm from the bone crest with a histomorphometric analysis in dogs. Nine mongrel dogs were used in this study: four dogs (8 canine teeth) for TSM group, 4 dogs (8 canine teeth) for composite group, and 1 dog (2 canine teeth) with cavities without restorations. Cavity preparation of 2×2×1 mm was created on the buccal aspect of the canines at 0.5 and 1.5 mm of the crestal bone. Cavities were restored with composite and TSM or were left unrestored as control. After 12 weeks of healing, the dogs were euthanized and blocks containing the tooth and soft tissues were processed. In all the specimens, the junction epithelium was stablished apical to the tooth preparations. A shorter distance to the bone (0.5 cavity) implies greater apical periodontal migration regardless of the material used. In the TSM groups, the connective tissue height and the distance between bone level and apical margin preparation were greater than those in the composite groups, while the epithelium height was less. However, there were no statistically significant differences comparing TSM and composite groups at either 0.5 mm or 1.5 mm (p > 0.05). Histologic analysis did not show periodontal reattachment to TSM or composite. In both cases, bone crest migrates apically. For that reason, it is recommended to perform composite restorations at the subgingival level whenever the distance to the bone crest is at least 2 mm. Both composite and TSM do not achieve reinsertion of the connective tissue in the biological width.

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

To search the literature and to critically evaluate the findings on the periodontal outcomes of restorations and tooth-supported fixed prostheses. 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. 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. 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.