Partial Extraction Therapy (Part 1): Applications in Full-Arch Dental Implant Therapy.

Partial extraction therapy (PET) is a set of surgical techniques that preserve a portion of the patient's own root structure to maintain blood supply derived from the periodontal ligament complex in order to maintain the periodontium and peri-implant tissues during restorative and implant therapy. PET includes the socket shield technique (SST), proximal shield technique (PrST), pontic shield technique (PtST), and root submergence technique (RST). In a traditional hybrid technique, total extraction and full-arch dental implant therapy often require significant bone reduction and palatal/lingual implant placement. In addition, postextraction preservation of the ridge architecture is a major challenge. This case series demonstrates the use of a combination of PET techniques with digital implant planning and guided implant surgery to achieve highly esthetic outcomes in full-arch implant therapy.

Partial Extraction Therapy (Part 2): Complication Management in Full-Arch Dental Implant Therapy.

Partial extraction therapy (PET) is a group of surgical techniques that preserve the periodontium and peri-implant tissues during restorative and implant therapy by conserving a portion of the patient's own root structure to maintain the blood supply, derived from the periodontal ligament complex. PET includes the socket shield technique (SST), proximal shield technique (PrST), pontic shield technique (PtST), and root submergence technique (RST). Although their clinical success and benefits have been demonstrated, several studies report possible complications. The focus of this article is to highlight management strategies for the most common complications associated with PET, including internal root fragment exposure, external root fragment exposure, and root fragment mobility.

Root submergence technique as a partial extraction therapy to preserve the alveolar ridge tissues: A systematic review and appraisal of the literature.

STATEMENT OF PROBLEM: As socket grafting with commercially available biomaterials has become popular, reports of the root submergence technique for ridge preservation have decreased. A systematic review of this partial extraction therapy is lacking. PURPOSE: The purpose of this systematic review was to review the root submergence technique as well as critically appraise the available data. MATERIAL AND METHODS: A review was carried out that observed the Participant, Intervention, Comparison, Outcomes (PICO) strategy and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The focused question was "What are the outcomes of the different methods to submerge tooth roots for ridge preservation?" Medical subject headings (MeSH) terms that related to the root submergence technique were searched in PubMed/MEDLINE, Scopus, and the Cochrane Library databases. RESULTS: A total of 7709 abstracts and study titles were individually screened from the initial search results. After reviewing the full-text articles and applying the selection criteria, the final included search results totaled 47 full-text articles for in-depth review. In 10 animal studies, 258 roots were studied in 34 dogs and 7 monkeys. Histological data confirmed that coronal bridging (bone or cementum growth over the cut root) was a common outcome. Of the vital roots submerged, the majority maintained their vitality. In 37 human studies, 475 roots were submerged and reported on. Subjective ridge preservation was often reported. Among the adverse healing outcomes, exposure of the root through the mucosa was the most common. Nonetheless, in animals, 86.8% of roots remained submerged; in humans, 74.7%. CONCLUSIONS: Root submergence is an established technique for ridge preservation. Exposure is a common complication, and correct technique may be key to its prevention. Further research of this partial extraction therapy is encouraged.

The root submergence technique at single tooth sites to short-span edentulous sites: A step-by-step partial extraction therapy protocol.

Submerging roots for ridge preservation was the earliest partial extraction therapy and has been described since the 1970s. Despite the approximately 47 animal and human studies published since, an updated and contemporary step-by-step protocol has not yet been provided. This technique report describes in detail how to manage submerged roots at single tooth sites and at short-span edentulous areas.

The socket shield technique with proximal extensions for single-rooted teeth.

The conventional socket shield (SS) design extends from the mesiolabial to the distolabial line angle. C-shaped SS, L-shaped SS, and proximal SS designs have proximal extensions that help to maintain the hard and soft tissue in the interproximal areas. This is beneficial for implant sites adjacent to an existing implant or an edentulous space. The most common complication of the socket shield technique (SST) is internal shield exposure. Due to anatomical features such as a scalloped ridge shape and an oval socket shape of some teeth, the risk of complications such as internal shield exposure, inadvertent SS displacement, and fracture of the SS during implant insertion is greater in proximal shield areas. The present article describes guidelines for case selection for proximal shield extensions, along with SS preparation and the selection of implant and prosthetic components.

Guided Bone Regeneration of a Seibert Class III Bone Defect With Bioactive Calcium Phosphosilicate Bone Graft: Human Histology and Clinical Report.

This clinical case aimed to achieve two main objectives. The first was to determine if the use of only calcium phosphosilicate bone graft as a regeneration material (with no autologous bone added) on a severe vertical and horizontal mandibular defect would allow enough bone to be obtained to enable the placement of dental implants. The second objective was to determine histologic characteristics of the regenerated site after a healing period of 10 months.

Three-Dimensional (3D) Facially Driven Workflow for Anterior Ridge Defect Evaluation: A Treatment Concept.

The esthetic rehabilitation of anterior ridge defects and achieving patient satisfaction have become major clinical challenges for dentists and technicians. Poor diagnosis and treatment planning are frequently associated with multiple surgical procedures that fail to meet patient expectations. The loss of hard and soft tissues in anterior ridges results in an esthetically compromised zone that affects the rehabilitation prognosis. The presence of interdental papilla and papillary configuration play a decisive role in patient satisfaction. A treatment plan considering esthetic parameters, prosthetic needs, and morphological defects must be used to improve treatment outcomes. Therefore, this study aims to propose a treatment concept for anterior ridge defects that focuses on digital evaluation systems and is guided by an ideal facially driven smile design project. In addition, the relevance of the papilla for esthetic outcomes and treatment alternatives for anterior ridge defects are also addressed.

Dimensions of the dentogingival tissue in the anterior maxilla. A CBCT descriptive cross-sectional study.

BACKGROUND: The characteristics of the periodontium in anterior teeth influence the outcomes and prognosis of different periodontal, implant, and restorative procedures. In the present study, CBCT images were used to determine alveolar bone thickness and, to a lesser extent, gingival thickness. The aim was to evaluate the use of CBCT to measure the dentogingival complex in the anterior maxilla. MATERIALS AND METHODS: CBCT scans from 25 healthy patients were taken and the maxillary anterior teeth (n = 138) analyzed in the radial plane. The study provided descriptive data on gingival thickness, alveolar bone thickness (horizontal measurements), and vertical measurements related to biologic width. RESULTS: The mean distance from gingival margin to bone crest (BC) was 3.4 ± 0.7 mm, and that between the cementoenamel junction and BC was 2.6 ± 1.0 mm. The average mid-labial gingival thickness 1 mm apical of the gingival margin was 1.0 ± 0.3 mm; a thinner gingiva was observed in females (P = 0.01) and canines (P < 0.001). The average crestal labial bone thickness was 0.8 ± 0.3 mm. In total, 62% of the tooth sites had a thin gingiva (< 1 mm), and 72% had thin labial bone plates; a moderate positive correlation was found between these parameters (P < 0.001). CONCLUSIONS: CBCT was effective in providing data on the thickness of the labial plate and gingiva as well as on the relationship among BC, CEJ, and gingival margin. The majority of tooth sites had thin labial bone and thin gingiva, with thinner gingiva observed in females and at canine sites.

The Ball Technique for Peri-implant Soft Tissue Augmentation Using a Xenogeneic Collagen Matrix: A Technical Report.

In the maxillary anterior region, augmentation to correct a soft tissue deficiency is often required for an esthetic outcome and long-term implant therapy success. This case series of three patients presents a novel approach for soft tissue augmentation using xenogeneic collagen matrix balls in the esthetic zone around the implants. This technique avoids a secondary donor site compared to autogenous connective tissue graft. With this technique, a horizontal soft tissue volume increase (range: 3 to 5 mm) was observed postsurgically and maintained at later follow-ups. The described ball technique offers a viable method for peri-implant mucosal augmentation in the maxillary anterior region.

Buccal Sliding Palatal Pedicle Flap Technique for Wound Closure After Ridge Augmentation.

One standard approach for wound closure after ridge augmentation is coronal flap advancement. Coronal flap advancement results in displacement of the mucogingival junction and reduction of the vestibulum. In the maxilla, a buccal sliding palatal flap can be applied for primary wound closure after ridge augmentation. The dissected part of the palatal connective tissue is left exposed, thus eliminating or reducing the amount of the coronal flap advancement respectively and increasing the amount of keratinized gingiva. In combination with guided soft tissue augmentation, this flap design enables a three-dimensional peri-implant soft tissue augmentation.

A decade of the socket-shield technique: a step-by-step partial extraction therapy protocol.

Ten years have passed since Hürzeler and coworkers first introduced the socket-shield technique. Much has developed and evolved with regard to partial extraction therapy, a collective concept of utilizing the patient's own tooth root to preserve the periodontium and peri-implant tissue. The specifications, steps, instrumentation, and procedures discussed in this article are the result of extensive experience in refining the socket-shield technique as we know it today. A repeatable, predictable protocol is requisite to providing tooth replacement in esthetic dentistry. Moreover, a standardized protocol provides a better framework for clinicians to report data relating to the technique with procedural consistency. This article aims to illustrate a reproducible, step-by-step protocol for the socket-shield technique at immediate implant placement and provisionalization for single-rooted teeth.

A novel guided surgery system with a sleeveless open frame structure: a retrospective clinical study on 38 partially edentulous patients with 1 year of follow-up.

BACKGROUND: This retrospective clinical study aims to present results of experience with a novel guided surgery system with a sleeveless, open-frame structure, in which the surgical handpiece (not the drills used for preparation) is guided. METHODS: This study was based on an evaluation of the records of partially edentulous patients who had been treated with a sleeveless open-frame guided surgery system (TWIN-Guide®, 2Ingis, Brussels, Belgium), between January 2015 and December 2017. Inclusion criteria were patients with good systemic/oral health and a minimum follow-up of 1 year. Exclusion criteria were patients who had been treated without a guide, or with a guide with sleeves, patients with systemic/oral diseases and who did not have a follow-up of 1 year. The main outcomes were surgical (fit and stability of the surgical guide, duration of the intervention, implant stability, and any intra-operative or immediate post-operative complication), biologic, and prosthetic. RESULTS: Thirty-eight patients (24 males, 14 females; mean age 56.5 ± 14.0 years) were included in the study. These patients had been treated with 110 implants inserted by means of 40 sleeveless, open-frame guides. With regard to fit and stability, 34 guides were excellent, 4 acceptable, and 2 inadequate for use. The mean duration of the intervention was 23.7 (± 6.7) minutes. Immediately after placement, 2 fixtures were not stable and had to be removed. Two patients experienced pain/swelling after surgery. The 108 surviving implants were restored with 36 single crowns and 32 fixed partial prostheses (24 two-unit and 8 three-unit bridges); these restorations survived until the 1-year follow-up, with a low incidence of biologic and prosthetic complications. CONCLUSIONS: Within the limits of this study, this novel guided surgery system with sleeveless, open frame-structure guides seems to be clinically reliable; further studies on a larger sample of patients are needed to confirm these outcomes.

The socket-shield technique at molar sites: A proof-of-principle technique report.

The socket-shield technique for avoiding postextraction tissue alteration was first described in 2010. The technique was developed for hopeless teeth in anterior esthetic sites but has not yet been described for molar sites. Managing postextractive ridge changes in the posterior region by prevention or regeneration remains a challenge. The socket shield aims to offset these ridge changes wherever possible, preserving the patient's residual tissues at immediate implants. This technique report describes the molar socket-shield step by step.

Esthetic tunnel exposure: A combination technique for peri-implant soft tissue development at second-stage surgery.

An esthetically pleasing result is the product of both prosthetic excellence and the health and quality of the soft tissue that frames the restoration. Management of the peri-implant coronal soft tissue is key to the ultimate success of treatment. This technique report describes an alternative, novel approach, combining established concepts and methods into a single technique to improve esthetic results.

The "Scalloped Guide": A Proof-of-Concept Technique for a Digitally Streamlined, Pink-Free Full-Arch Implant Protocol.

Inadequate restorative space can result in mechanical, biologic, and esthetic complications with full-arch fixed implant-supported prosthetics. As such, clinicians often reduce bone to create clearance. The aim of this paper was to present a protocol using stacking computer-aided design/computer-assisted manufacturing (CAD/CAM) guides to minimize and accurately obtain the desired bone reduction, immediately place prosthetically guided implants, and load a provisional that replicates predetermined tissue contour. This protocol can help clinicians minimize bone reduction and place the implants in an ideal position that allows them to emerge from the soft tissue interface with a natural, pink-free zirconia fixed dental prostheses.

Flapless Postextraction Socket Implant Placement, Part 3: The Effects of Bone Grafting and Provisional Restoration on Soft Tissue Color Change-A Retrospective Pilot Study.

This article presents the results of a soft tissue color study on flapless immediate implant therapy from a sample of 23 patients who received either a provisional restoration alone or with bone grafting. The gingival color in clinical photographs was measured for the implant and for the contralateral tooth site at 2.0 and 5.0 mm below the free gingival margin using Photoshop software (Lightroom CC, Adobe). The average color difference (ΔE) values for the two groups were 2.6 and 2.4 at 2.0 mm and 1.9 and 2.5 at 5.0 mm from the free gingival margin, respectively. Approximately 80% of the sites were below the visibly perceptible threshold (ΔE = 3.1 ± 1.5) and not detectable by the human eye. The use of provisional restorations has shown positive outcomes on the stability of peri-implant soft tissue thickness and lower ΔE values. Further research is required to assess esthetic outcomes inclusive of color change relative to the clinical treatment rendered.

Human Histologic Evidence of New Bone Formation and Osseointegration Between Root Dentin (Unplanned Socket-Shield) and Dental Implant: Case Report.

The socket-shield technique described 7 years ago has since grown in its reporting in the literature as a valid method of ridge preservation at immediate implant placement. To date, large clinical cohorts with up-to-4-year follow-up have been reported. Additionally, evidence of tissue histology at the dental implant and socket-shield has been demonstrated in the animal model. However, human histologic evidence has not yet been available, and the clinician's uncertainty regarding the tissues that may form between the socket-shield and dental implant may remain unanswered until now. This case report presents the first human histologic evidence that bone may entirely fill the space between root dentin and an osseointegrated implant surface.

A retrospective evaluation of 128 socket-shield cases in the esthetic zone and posterior sites: Partial extraction therapy with up to 4 years follow-up.

OBJECTIVES: Tooth loss results in an inevitable alveolar ridge reduction. This has established a cautionary approach to extract, wait, augment, and insert the implant, in lieu of immediate placement. However, saving the tooth or part of it whenever possible is more conservative and supports the vital periodontal tissue buccofacial to an implant. The purpose of this cases series was to report on implant survival using this technique in a large cohort of patients at mid-term follow-up. MATERIALS AND METHODS: A private practice patient database was searched for all patients having received socket-shield treatment in conjunction with immediate implant placement. Of the results returned, 128 met the inclusion criteria of ≥12 months from date of restoration, or failing prior to definitive restoration. These patients were recalled for evaluation of the restored implants up to 4 years post-treatment. RESULTS: Seventy immediate implants with socket-shields were placed in female patients and 58 in males, age range 24-71 (mean 39 years). The distribution of sites treated were: maxillary incisors (64%), premolars (22%), canines (14%); maxilla (89.9%), mandible (10.1%). 123/128 implants osseointegrated and survived 1-4 years following restoration (survival rate 96.1%). A combined complication rate of 25/128 implants occurred (19.5%). Five implants failed to osseointegrate and were removed. The remaining 20 complications were all managed or observed without management, with implants surviving at mid-term follow-up. CONCLUSIONS: Notwithstanding technique sensitivity and the need for randomized control studies, this case series demonstrates that the socket-shield performs competitively when compared to implant survival rates in both conventional immediate and delayed implant placement.

Use of platelet-rich fibrin in regenerative dentistry: a systematic review.

OBJECTIVES: Research across many fields of medicine now points towards the clinical advantages of combining regenerative procedures with platelet-rich fibrin (PRF). This systematic review aimed to gather the extensive number of articles published to date on PRF in the dental field to better understand the clinical procedures where PRF may be utilized to enhance tissue/bone formation. MATERIALS AND METHODS: Manuscripts were searched systematically until May 2016 and separated into the following categories: intrabony and furcation defect regeneration, extraction socket management, sinus lifting procedures, gingival recession treatment, and guided bone regeneration (GBR) including horizontal/vertical bone augmentation procedures. Only human randomized clinical trials were included for assessment. RESULTS: In total, 35 articles were selected and divided accordingly (kappa = 0.94). Overall, the use of PRF has been most investigated in periodontology for the treatment of periodontal intrabony defects and gingival recessions where the majority of studies have demonstrated favorable results in soft tissue management and repair. Little to no randomized clinical trials were found for extraction socket management although PRF has been shown to significantly decrease by tenfold dry sockets of third molars. Very little to no data was available directly investigating the effects of PRF on new bone formation in GBR, horizontal/vertical bone augmentation procedures, treatment of peri-implantitis, and sinus lifting procedures. CONCLUSIONS: Much investigation now supports the use of PRF for periodontal and soft tissue repair. Despite this, there remains a lack of well-conducted studies demonstrating convincingly the role of PRF during hard tissue bone regeneration. Future human randomized clinical studies evaluating the use of PRF on bone formation thus remain necessary. CLINICAL RELEVANCE: PRF was shown to improve soft tissue generation and limit dimensional changes post-extraction, with little available data to date supporting its use in GBR.