Horn Lay Wang

Rationale for the application of immediate load in implant dentistry: part II.

Immediate loading in implant dentistry is increasing in popularity as a clinical procedure. A scientific rationale of immediate occlusal loading of the implant support system should emphasize methods to decrease surgical trauma during implant placement and to decrease bone loading trauma during the early loading period. The surgical trauma may be reduced by decreasing heat generation and pressure necrosis. The early loading trauma may be decreased by decreasing the bone strain adjacent to the implant interface. Greater microstrain conditions in bone increase the remodeling rate of bone. The higher the remodeling rate, the weaker the bone and the more risk of occlusal overload. Occlusal overload may lead to implant failure. Since strain is directly related to stress, methods to decrease stress are beneficial. In the present report, the stress-reducing influences include increasing the number of implants.

Implant Compression Necrosis : Current Understanding and Case Report

BACKGROUND Implants fail for a variety of reasons; it can be difficult to determine the exact cause of failure, especially if there are multiple contributing factors. Overcompression of the adjacent bone during implant placement is a potential contributing factor to implant failure that is not well documented in the literature. METHODS This case report reviews the concept of bone loss induced by overcompression and presents a case of implant failure with overcompression as a potential etiology. Histology, radiographs, and clinical data are presented that document the failure of four implants placed in the posterior mandible of a 48-year-old female patient. RESULTS After uneventful implant placement, one implant exfoliated 3 weeks postoperatively. The other three implants were removed because of severe bone loss up to 2 months later. Histology of the area revealed non-viable bony sequestra with bacterial colonization. CONCLUSIONS This case highlights unusual implant failures that likely occurred as a result of overcompression of the bone during placement. Areas involving dense bone seem to be at increased risk for compression necrosis.

Common implant-related advanced bone grafting complications: classification, etiology, and management.

Bone grafting has become an essential part of implant dentistry. Thanks to the advancement of grafting technology, areas that could only be managed with removable dentures or teeth-supported fixed prostheses can now be successfully treated with implant-supported prosthesis. Nonetheless, the complications associated with bone grafting procedures have slowly emerged to be one of the main challenges to many clinicians. A Medline literature search of articles published from 1984 to 2006 related to advanced bone grafting complications were selected and analyzed. To make it easier to understand, implant-associated bone grafting complications were classified into: socket augmentation related, guided bone regeneration related, onlay grafting (autogenous or allogenic) related, sinus lift related, and others. Etiologies associated with the above complications were categorized into: material related, technique related, anatomical related, patient related, and others. In summary, management of grafting complications requires proper diagnosis of all contributing etiologies and then providing necessary treatments that include nonsurgical pharmacological as well as surgical interventions based upon their clinical implications. Nonetheless, prevention of complication is of the utmost importance.

Impact of Maintenance Therapy for the Prevention of Peri-implant Diseases: A Systematic Review and Meta-analysis.

At the present time, peri-implantitis has become a global burden that occurs with a frequency from 1% to 47% at implant level. Therefore, we aimed herein at assessing the impact of peri-implant maintenance therapy (PIMT) on the prevention of peri-implant diseases. Electronic and manual literature searches were conducted by 3 independent reviewers using several databases, including MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register, for articles up to June 2015 without language restriction. Articles were included if they were clinical trials aimed at demonstrating the incidence of peri-implant diseases under a strict regime or not of PIMT. Implant survival and failure rate were studied as secondary outcomes. A meta-analysis was conducted to evaluate the influence of PIMT and other reported variables upon peri-implant diseases. Thirteen and 10 clinical trials were included in the qualitative and quantitative analysis, respectively. Mucositis was affected by history of periodontitis and mean PIMT at implant and patient levels, respectively. Similarly, significant effects of history of periodontal disease were obtained for peri-implantitis for both implant and patient levels. Furthermore, mean PIMT interval was demonstrated to influence the incidence of peri-implantitis at implant but not patient level. PIMT interval showed significance at both levels. For implant survival, implants under PIMT have 0.958 the incident event than those with no PIMT. Within the limitations of the present systematic review, it can be concluded that implant therapy must not be limited to the placement and restoration of dental implants but to the implementation of PIMT to potentially prevent biologic complications and hence to heighten the long-term success rate. Although it must be tailored to a patient’s risk profiling, our findings suggest reason to claim a minimum recall PIMT interval of 5 to 6 mo. Additionally, it must be stressed that even in the establishment of PIMT, biologic complications might occur. Thus, patient-, clinical-, and implant-related factors must be thoroughly explored.

Reconstructive Procedures for Treating Peri-implantitis A Systematic Review

This review aimed at evaluating the effectiveness of reconstructive procedures for treating peri-implantitis. Searches of electronic databases and cross-referencing were performed for human comparative clinical trials with ≥10 implants for ≥12 months of follow-up, reporting radiographic defect fill and at least one of the following parameters: probing depth reduction, clinical attachment level gain, bleeding on probing reduction, and mucosal recession. The searches retrieved 430 citations. Only 1 randomized controlled trial was identified, which compared reconstructive therapy and open flap debridement. Case series studies were also included to evaluate the overall performance of the reconstructive procedures. Twelve studies were finally included. Meta-analysis revealed that the weighted mean radiographic defect fill was 2.17 mm (95% confidence interval [CI]: 1.46-2.87 mm), probing depth reduction was 2.97 mm (95% CI: 2.38-3.56 mm), clinical attachment level gain was 1.65 mm (95% CI: 1.17-2.13 mm), and bleeding on probing reduction was 45.8% (95% CI: 38.5%-53.3%). Great variability in reparative outcomes was found, attributed to patient factors, defect morphology, and reconstructive agents used. Currently, there is a lack of evidence for supporting additional benefit of reconstructive procedures to the other treatment modalities for managing peri-implantitis.

Long-term Radiographic and Clinical Outcomes of Regenerative Approach for Treating Peri-implantitis: A Systematic Review and Meta-analysis.

PURPOSE The purpose of this systematic review was to evaluate long-term outcomes of regenerative procedures for treating peri-implantitis. MATERIALS AND METHODS Electronic searches of five databases and hand searches of journals were performed to identify human trials that had treated more than 10 periimplantitis lesions using a regenerative approach with a follow-up period of at least 36 months. To meet the inclusion criteria, studies had to report at least one of the following parameters: radiographic bone fill (RBF), probing depth (PD) reduction, clinical attachment level gain, bleeding on probing reduction, and mucosal level gain. The pooled weighted mean and the 95% confidence interval (CI) of each variable were estimated. RESULTS The searches yielded 1,412 records, and after evaluating titles, abstracts, and full texts, 5 case series and 1 controlled trial were included for quantitative data synthesis. Meta-analysis of the studies for the amount of RBF revealed a weighted mean of 2.41 mm (range, 1.46 to 3.30 mm) with 95% CI. For PD reduction, the weighted mean was 3.06 mm (range, 1.24 to 5.21 mm). CONCLUSION There is limited evidence in the literature reporting long-term results of the regenerative approach for treating peri-implantitis. Within the limits of this meta-analysis, regenerative treatment of peri-implantitis resulted in a mean radiographic defect fill of 2.41 mm after a minimum healing time of 36 months. However, this finding must be interpreted with caution, since it is difficult to discern between grafting material and newly formed bone.

Effect of barrier membranes on the outcomes of maxillary sinus floor augmentation: a meta-analysis of histomorphometric outcomes.

PURPOSE Sinus floor elevation via the lateral window approach represents a reliable technique for augmenting bone volume in the atrophic posterior maxilla. However, controversy remains regarding the effect of placement of a barrier membrane over the lateral window. This histomorphometric meta-analysis sought to clarify the effect of barrier membranes in lateral window sinus augmentation. MATERIALS AND METHODS An electronic search of three databases and a hand search in implant-related journals for studies published through January 2013 in the English language was conducted. Randomized controlled trials, prospective human clinical studies, retrospective investigations, and case series reporting histomorphometric results after sinus elevation using the lateral window approach with at least six patients and a minimum follow-up period of 6 months were included. RESULTS The initial search yielded 1,040 articles, of which 94 were further evaluated for eligibility. Finally, 37 studies were chosen and separated into membrane (group 1) and no-membrane (group 2) groups. Similar vital bone formation was found in both groups: 32.36% for group 1 and 33.07% for group 2. CONCLUSION Based does not influence the amount of vital bone formation after sinus augmentation. Additionally, the type of grafting material used and healing time did not influence the histomorphometric outcome.

Vertical Bone Grafting and Periosteal Vertical Mattress Suture for the Fixation of Resorbable Membranes and Stabilization of Particulate Grafts in Horizontal Guided Bone Regeneration to Achieve More Predictable Results: A Technical Report.

Osteosynthesis screws and titanium or resorbable pins have been recommended for fixing guided bone regeneration (GBR) membranes and stabilizing the graft. However, the removal of fixation screws or pins often requires an additional surgical procedure. This article presents a periosteal suturing technique with resorbable sutures for the fixation of grafts and membranes in GBR in single implant sites. This technique avoids potential complications of using fixation screws or pins, such as perforation of the roots when inserting the pins, and eliminates the need for a second retrieval surgery.

Is Metal Particle Release Associated with Peri-implant Bone Destruction? An Emerging Concept:

Peri-implant diseases affecting the surrounding structures of endosseous dental implants include peri-implant mucositis and peri-implantitis. The prevalence of peri-implantitis ranges between 15% and 20% after 10 y, highlighting the major challenge in clinical practice in the rehabilitation of dental implant patients. The widespread nature of peri-implant bone loss poses difficulties in the management of biological complications affecting the long-term success of osseointegrated implant reconstructions. Metal and titanium particles have been detected in peri-implant supporting tissues. However, it remains unclear what mechanisms could be responsible for the elicitation of particle and ion release and whether these released implant-associated materials have a local and/or systemic impact on the peri-implant soft and hard tissues. Metal particle release as a potential etiologic factor has been intensively studied in the field of orthopedics and is known to provoke aseptic loosening around arthroplasties and is associated with implant failures. In dental medicine, emerging information about metal/titanium particle release suggests that the potential impact of biomaterials at the abutment or bone interfaces may have an influence on the pathogenesis of peri-implant bone loss. This mini-review highlights current evidence of metal particle release around dental implants and future areas for research.

Comparison of Freeze-Dried and Solvent-Dehydrated Acellular Dermal Matrix for Root Coverage: A Randomized Controlled Trial.

The prevalence of gingival recession has been estimated at around 22.5% in people aged older than 29 years. Classic treatment approaches include the use of connective tissue grafts in combination with coronally advanced flaps (CAFs). To reduce morbidity and the need for a secondary surgical site, allograft materials are currently being used. Nevertheless, long-term randomized studies testing the efficacy of these materials are lacking. Hence, the aim of the present randomized controlled clinical trial was to compare two acellular dermal matrix (ADM) materials produced by different processing techniques, freeze-dried (FDADM) and solvent-dehydrated ADM (SDADM). At 12 months, both groups showed significant improvement in attachment level, recession depth, and recession width. A mean improvement in attachment level of 2.0 ± 1.08 mm for FDADM and 2.0 ± 0.70 mm for both SDADM was achieved (P = .002). Root coverage after 12 months was 80.66 ± 22.90% for FDADM and 80.97 ± 18.08% for SDADM. Hence, it was concluded that both FDADM and SDADM grafting materials can successfully achieve root coverage in Miller Class I and II recession defects for up to 12 months when used in combination with CAFs.