Late Dental Implant Failures Associated with Retained Root Fragments: Case Reports with Histologic and SEM Analysis.

Interest has recently developed in the purposeful retention of root fragments with their periodontal apparatus to support bone and soft tissue at immediate implant sites in the esthetic zone. This methodology is designed to avoid bone grafting, connective tissue grafts, and the use of membranes and may have short-term benefits in terms of tissue preservation. However, it is not completely without long-term risks. At times, implants may be unintentionally placed into edentulous sites where root fragments remain. This report presents two cases of long-term failure postloading associated with unintentionally retained root fragments. Histologic evaluation evidenced retained root fragments in close association with dental implants and the surrounding bone. Scanning electron microscopic evaluation revealed that the failed implant surfaces were infiltrated by bacterial deposits and calculus. Clinicians should exercise caution when placing dental implants in sites with retained root fragments, as long-term risks may be associated with this therapy.

Unintentional root fragment retention in proximity to dental implants: a series of six human case reports.

There has been renewed interest in intentionally placing dental implants in proximity to or in contact with tooth root fragments. In clinical practice, human teeth are usually extracted due to nonrestorable caries, vertical or horizontal root fractures, periodontal disease, or endodontic failure, which is commonly accompanied by inflammation and bacterial contamination. The aim of this case series is to present the adverse effects in humans of clinically undetected root-to-implant contact (CURIC), where implants were unintentionally placed in proximity to undetected retained root fragments. The adverse effects of small (3 to 5 mm) root fragments were detectible 6 to 48 months post implant placement. Three out of seven implants in six patients were removed due to severe coronal bone loss. This differs from retrograde peri-implantitis, where only the apical area of the implant is affected and the coronal portion remains integrated. The detrimental effect of root fragment-to-implant contact is described along with its clinical management. Based on the review of currently relevant data, mixed results have been documented regarding the success of dental implants in proximity to tooth-root fragments. Careful evaluation of long-term, postloading results in humans where hopeless teeth have been extracted due to infection and significant bone loss are required before intentional root fragment retention is considered a safe and reliable clinical option for implant placement.

Periodontal soft tissue non-root coverage procedures: a consensus report from the AAP Regeneration Workshop.

BACKGROUND: Soft tissue grafting for the purposes of increasing the width of keratinized tissue (KT) is an important aspect of periodontal treatment. A systematic review was analyzed, focusing on non-root coverage tissue grafts. The references were updated to reflect the current literature. METHODS: To formulate the consensus report, group members submitted any new literature related to the topic that met criteria fitting the systematic review, and this information was reviewed for inclusion in this report. A consensus report was developed to summarize the findings from the systematic review and to guide clinicians in their treatment decision-making process. RESULTS: Forty-six articles met the criteria for inclusion in the final analysis, and two articles were added that were used to formulate this consensus report. A list of eight clinically relevant questions was posed, and consensus statements were developed. CONCLUSIONS: The evidence suggests that a minimum amount of KT is not needed to prevent attachment loss (AL) when optimal plaque control is present. However, if plaque control is suboptimal, a minimum of 2 mm of KT is needed. The standard procedure to predictably gain KT is the autogenous gingival graft. There is limited evidence for alternative treatment options. However, additional research may offer promising results in certain clinical scenarios. CLINICAL RECOMMENDATIONS: Before patient treatment, the clinician should evaluate etiology, including the role of inflammation and various types of trauma that contribute to AL. The best outcome procedure (autograft) and alternative options should be reviewed with the patient during appropriate informed consent. Proper assessment of the outcome should be included during supportive periodontal care.

Periodontal Soft Tissue Non-Root Coverage Procedures: Practical Applications From the AAP Regeneration Workshop.

Focused Clinical Question: What are the indications and clinical applications for gingival augmentation procedures, and what factors guide the choice among treatment options in specific situations? Summary: Although there is still controversy regarding whether there needs to be a minimum amount of attached gingiva to maintain the stability of the gingival margin, prospective and retrospective studies have shown that, in the presence of suboptimal plaque control and clinical inflammation, attachment loss and gingival recession (GR) may result unless a minimum amount of keratinized tissue (KT) and attached gingiva are present. Treatment of mucogingival deformities requires gingival augmentation procedures that address both a functional and esthetic component for the patient. Although free gingival grafts (FGGs) are considered the gold standard for treatment of GR defects to obtain root coverage, augmentation of KT and attached gingiva may be accomplished by FGG or other autogenous grafting options, including the free connective tissue graft, the lateral pedicle graft, and the double papilla technique. In addition, the modified apically repositioned flap can be considered in some instances. Alternatives to autogenous graft tissue include acellular dermal matrix, extracellular matrix membrane, bilayer collagen matrix, and living cellular construct. Conclusions: Understanding the clinical importance of the presence of a minimum amount of attached gingiva in patients with suboptimal hygiene is an important first step in addressing the condition. Patient education to address plaque control and counseling to quit smoking in patients who are smokers help enhance the success of these mucogingival surgical procedures. An analysis of patient-specific factors will help with the appropriate choice of surgical procedures aimed at augmenting the dimension of KT/attached gingival tissue. Evidence supporting the treatment decisions described in this practical application is summarized in the companion papers from the American Academy of Periodontology Regeneration Workshop (Kim and Neiva, J Periodontol 2015;86(Suppl.):S56-S72; Scheyer et al., J Periodontol 2015;86(Suppl.):S73-S76).

Planned labial plate advancement with simultaneous single implant placement for narrow anterior ridges followed by reentry confirmation.

This article reports on the efficacy of a technique involving expansion of edentulous ridges of less than 3 mm in width by means of a planned green stick fracture of the labial plate and simultaneous implant placement without the need for membranes. This retrospective case series includes long-term results from 21 patients with 36 sites and 37 implants with a mean follow-up of 4 years, 5 months from the date of restoration. Freeze-dried bone allograft was used in 22 sites (61%) to augment the ridge. Reentry at stage-two surgery confirmed the preservation of the displaced labial plate after implant integration. Three implants were removed prior to the planned uncovering because of incomplete healing of the overlying gingival tissue; therefore, the survival rate of the labial advancement was 92%. No implants failed after definitive prosthetic loading; therefore, the cumulative survival rate of loaded implants was 100%. No significant bone loss was detected at the final follow-up visit. Follow-up after loading ranged from 9 to 148 months. Advancement of the labial plate with simultaneous implant placement to gain horizontal ridge width dimension was shown to be a reliable and practical procedure for single-tooth sites where other grafting methods are often difficult.

Vertical ridge augmentation procedure using guided bone regeneration, demineralized freeze-dried bone allograft, and miniscrews: 4- to 13-year observations on loaded implants.

This retrospective case series presents results from eight patients treated with demineralized freeze-dried bone allograft particles and barrier membranes using either miniscrews or implants to support the membrane in seven patients. In all patients, the amount of vertical bone regeneration enabled placement of one or more implants in the graft sites, followed by loading with definitive prostheses at least 5.5 months after implant placement. Marginal bone heights around the implants have remained stable throughout 4 to 13 years of follow-up.

A descriptive study on retrieved non-threaded and threaded implant designs.

OBJECTIVES: In the light microscope compare the amount of bone saucerization for non-threaded cylindrical and threaded implant designs in retrieved samples from patients. MATERIAL AND METHOD: Consecutively received retrieved oral implants from 117 patients, whereof 85 non-threaded cylindrical and 85 Brånemark implants, have been included in the study. For 75 non-threaded cylindrical and 46 Brånemark implants was the entire implant length available for calculation. Undecalcified ground sections were investigated in the light microscope with calculation of percentage of implant length coronal to the first bone-implant contact and percentage of bone to implant contact. RESULTS: Mean value for implant length coronal to first bone-implant contact was 65%, standard error of the mean (SEM) 3 (range 0-100%), for non-threaded cylindrical implants and 43%, SEM 6 (range 0-100%) for Brånemark implants. Mean values of bone contact along the entire implant length was 23%, SEM 2 (range 0-65%), for the non-threaded cylindrical implants and 33%, SEM 5 (range 0-93%) for the Brånemark implants. CONCLUSION: Within the limitations of this retrospective, retrieval study non-threaded cylindrical implants demonstrated a greater bone saucerization when evaluated in the light microscope.