The placement of immediate dental implants in the esthetic zone is a highly successful procedure, however it requires careful case selection. Depending on the structural integrity of the alveolar socket and the gingival level, either an implant can be placed immediately and provisionalized or its insertion may need to be delayed. If the extraction site is compromised, implant placement should be deferred to allow bone or soft-tissue grafting or a combination of both to facilitate esthetic implant placement. In addition, two other treatment factors need to be considered with regard to immediate placement: (1) if the implant has low primary stability (ie, low insertion torque value), a custom healing abutment should be fabricated to maintain tissue contour and retain bone placed into the buccal gap; (2) if there is high primary stability (ie, high insertion torque value), fabrication of an immediate fixed provisional will preserve tissue contour, hold a buccal gap bone graft in place, and provide an esthetic result. At sites where the implant will be placed, factors favoring immediate placement include the following: coronal position of the gingiva compared to adjacent teeth, a type I socket classification, and class I or II sagittal root position. The purpose of this article is to present clinical guidelines that can aid in the decision-making process for delayed versus immediate implant placement.

After tooth extraction, a modeling and remodeling phase of bone and soft tissues occurs. It has been fully demonstrated that bone resorption as high as 50% can take place regarding ridge width and a variable amount concerning ridge height, making it difficult to perform implant surgery.
Active members of the Italian Academy of Osseointegration (IAO) participated in this Consensus Conference, and three systematic reviews were conducted before the meeting to provide guidelines on alveolar ridge preservation procedures. The systematic reviews covered the following topics: (1) What material best preserves the dimensions of the ridge horizontally and vertically?; (2) what material favors the formation of the highest quantity of new bone?; (3) which technique would best seal the socket?; and (4) what effect does alveolar ridge preservation have on soft tissues?
The main conclusions reached by the assembly were that alveolar ridge preservation is advisable after dental extraction, particularly in esthetic areas, in proximity of anatomical structures (ie, maxillary sinus, inferior alveolar nerve, and mental foramen), whenever the treatment plan requires delayed placement, and whenever patients ask to postpone implant insertion for various reasons. Socket debridement is advised before the use of a \"regenerative material,\" and xenograft is considered the gold standard material to maintain ridge dimensions. Another indication is antibiotic therapy, which is recommended in the case of alveolar ridge preservation (amoxicillin 2 g 1 hour before the intervention and 1 g every 12 hours for 6 days). A membrane or autologous soft tissue should be used to seal the socket and protect the regenerative material, and the indicated reentry time (implant insertion) is 4 to 6 months.
This Consensus Conference agreed that the adoption of alveolar ridge preservation can effectively prevent physiologic bone loss, especially in esthetic areas. It is recommended to cover the xenograft material with a membrane or autologous soft tissue, and antibiotic therapy is advisable.

OBJECTIVE: To analyse and compare the dimensional changes of unassisted extraction sockets with alveolar ridge preservation (ARP) techniques and investigate any factors that impact the resorption of the alveolar bone.
METHODS: A systematic search was conducted to identify randomised clinical trials (RCTs). All data were extracted, and a meta-analysis was performed for the changes in all buccolingual ridge width, midbuccal and midlingual ridge height, and mesial and distal ridge height, and horizontal width at reference points apical to the crestal area.
RESULTS: Based on 14 RCTs, the effectiveness of ARP in reducing the dimensions of the postextraction alveolar socket was confirmed. The clinical magnitude of this effect was 1.95 mm in the buccolingual ridge width, 1.62 mm in the midbuccal ridge height, and 1.26 mm on the midlingual ridge height. Additionally, 0.45 mm and 0.34 mm for mesial and distal ridge height, and 1.21 mm, and 0.76 mm for ridge width changes at points 3 and 5 mm apical to the crest were noted. Meta-regression analyses revealed that the reflection of flaps and primary wound coverage during ARP may have detrimental effects on bone remodelling, while no statistical significance was observed for any of the bone graft substitutes or the percentage of molar sockets.
CONCLUSIONS: Regardless of the protocol, ARP can only minimise ridge resorption. ARP is most effective on horizontal ridge width, providing the most benefit coronally (approximating the crest), followed by the midbuccal ridge height.

The transition from a tooth requiring extraction to its replacement (with a dental implant) requires a series of clinical decisions related to timing, approach, materials, cost-effectiveness and the assessment of potential harm and patient preference. This workshop focused on the formulation of evidence-based consensus statements and clinical recommendations.
Four systematic reviews covering the areas of alveolar ridge preservation/bone grafting, immediate early and delayed implant placement and alveolar bone augmentation at the time of implant placement in a healed ridge formed the basis of the deliberations. The level of evidence supporting each consensus statement and its strength was described using a modification of the GRADE tool.
The evidence base for each of the relevant topics was assessed and summarized in 23 consensus statements and 12 specific clinical recommendations. The group emphasized that the evidence base mostly relates to single tooth extraction/replacement; hence, external validity/applicability to multiple extractions requires careful consideration. The group identified six considerations that should assist clinicians in clinical decision-making: presence of infection, inability to achieve primary stability in the restoratively driven position, presence of a damaged alveolus, periodontal phenotype, aesthetic demands and systemic conditions.
A substantial and expanding evidence base is available to assist clinicians with clinical decision-making related to the transition from a tooth requiring extraction to its replacement with a dental implant. More high-quality research is needed for the development of evidence-based clinical guidelines.

This prospective case series proposes a method for selecting the diameter of immediate postextraction anterior implants and guiding the placement position of the implant based on the buccolingual dimension with the goal of preserving the buccal bone wall. The socket buccolingual distance was measured to determine the appropriate implant diameter, considering a 3-mm gap to the buccal wall. Pre- and postoperative cone-beam computed tomography images were compared to evaluate the buccal bone. The socket width measurements were not significantly different (P = .931). The mean widths of the postoperative buccal bone were 3.01 ± 0.18 mm, 2.92 ± 0.38 mm, and 2.83 ± 0.42 mm for the crestal bone at the implant platform and at 2 and 4 mm apically, respectively, after 35 months of follow-up. This new diameter selection method for implants demonstrated predictable buccal plate preservation.

BACKGROUND: Different therapeutic concepts and methods have been proposed for improving dental implant outcomes in three specific clinical situations: (i) the fresh extraction socket with alveolar ridge preservation protocols; (ii) the posterior maxilla with limited bone height with either the placement of regular-sized implants after sinus elevation and grafting or short dental implants and; (iii) the posterior mandible with limited bone height with either vertical bone augmentation and placement of implants or short dental implants.
METHODS: Three systematic reviews, based on randomized and controlled clinical trials have evaluated the efficacy of these different therapeutic modalities in terms of dental implant outcomes.
CONCLUSIONS: Interventions aimed for alveolar ridge preservation have shown efficacy in terms of allowing the placement of dental implants and for reducing the need of further augmentation procedures at implant placement. Both therapeutic options, the placement of implants after sinus elevation and grafting or short dental implants, were valid alternatives in the treatment of the posterior maxilla with deficient bone availability, although short implants resulted in fewer complications. Similarly, the placement of implants in vertically augmented bone rendered comparable outcomes with those of short implants in the treatment of the posterior mandible, but short implants resulted in fewer complications.

BACKGROUND: The objectives of this working group were to update the existing knowledge base in computer-guided implant treatment (accuracy and clinical advantages), to search for scientific evidence on the need for keratinized tissue around implants, and to review recent literature in the search for new insights into ridge preservation after tooth extraction.
METHODS: The literature was systematically searched and critically reviewed. Four manuscripts were prepared, three systematic and one narrative review, that allowed the group to develop evidence-based conclusions, as well as clinical implications and recommendations for future research.
RESULTS: The results and conclusions of the reviews were presented in the following papers: Van Assche et al. (2012) Accuracy of computer-aided implant placement. Hultin et al. (2012) Clinical advantages of computer-guided implant placement: a systematic review. Wennström & Derks (2012) Is there a need for keratinized mucosa around implants to maintain health and tissue stability? Wang & Lang () Ridge preservation after tooth extraction. The group\'s consensus statements, clinical implications and implications for future research are presented in this article.

The reliability of immediately loaded dental implants in the mandible has prompted many to investigate their application in the maxilla. Although the body of literature is growing, the long-term survivability of immediate loading in the maxilla is still pending. This review of literature investigates the status of immediate loading of dental implants in the maxilla to determine its predictability as a treatment option for partial and complete maxillary edentulism. Current terminology in the field is summarized first. Subsequently, the rationale and advantages of immediate loading in the maxilla are reviewed, and the relationships between immediate loading and osseointegration, primary stability, implant design, micromotion, immediate implant placement, and bone character are explored. The importance of a prosthodontically driven implant treatment plan emphasizing the role of splinting a high-precision and passively fitting implant restoration with reduced micromotion under function is summarized. The reliability and predictability of immediately loaded implants as a treatment option are proposed, and recommended guidelines for the successful delivery of immediately loaded implants in the maxilla are presented.

暂无摘要。

With the increased popularity of implants and focus on .. esthetics, there is great emphasis on idealized bone foundation and soft tissue contours. The goal of reconstructive procedures is to provide peri-implant bone that support and maintain gingival contours. This article reviews ridge deficiency diagnosis and predicts the need for bone augmentation before tooth extraction. It also presents early intervention to minimize bone loss, various bone reconstruction techniques, and suggests predictable methods for different clinical scenarios.