Immediate Implant Placement with Immediate Loading in Periodontally Compromised Patients: A Literature Review Nabeeh Abdullah AlQahtani

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1 Received: 18 th December 2015 Accepted: 20 th March 2016 Conflicts of Interest: None Source of Support: Nil Review Article Doi: /jioh Immediate Implant Placement with Immediate Loading in Periodontally Compromised Patients: A Literature Review Nabeeh Abdullah AlQahtani Contributor: Assistant Professor, Department of Periodontics and Community Sciences, Division of Periodontics, College of Dentistry, King Khalid University, Abha, Saudi Arabia. Correspondence: Dr. AlQahtani NA. Department of Periodontics and Community Sciences, College of Dentistry, P.O. Box: 3263, King Khalid University, Abha 61471, Kingdom of Saudi Arabia. Phone: +(0) nabeehab@kku.edu.sa How to cite the article: AlQahtani NA. Immediate implant placement with immediate loading in periodontally compromised patients: A literature review. J Int Oral Health 2016;8(5): Abstract: The aim of the present literature review was to assess the outcomes of immediate implant placement with immediate loading in periodontally compromised patients and to review the guidelines for this type of treatment. The MEDLINE-PubMed databases were searched for appropriate articles addressing the purpose of this study. The search included articles published in English literature from 1977 up to The placement of implants immediately in fresh sockets with immediate loading in periodontally compromised patients is a promising treatment modality, but the practitioner should follow a very strict protocol. Further long-term research is required to prove the predictability of utilizing guided bone regeneration around immediate implants with immediate loading in periodontally compromised patients. Key Words: Immediate implant placement, immediate loading, periodontally compromised patients Introduction Dental implants were first described and successfully employed in the treatment of completely mandibles edentulism in 1965, 1 implant supported various designs of prostheses have been shown to be a predictable and reliable treatment option for both partially and fully edentulous patients. 2-6 Historically, the initial phase of implant integration should be at least 4-6 months before any restoration was placed as described by the original Branemark s protocol. 7 Consequently, the whole treatment time will take 24 months or longer, resulting in a significant delay between the time of implant placement and the final restoration. Other concerns with using Branemark s protocol, 7 include alveolar bone loss, longer treatment time with edentulism, additional surgical procedure, and patient psychological impaction. After extraction, bone remodeling will take place to the alveolar ridge, which causes bone volume loss, especially within the 1 st year. 8,9 The same study reported that overall reduction in ridge height of 4.0 mm and 25% loss of total bone volume occurred within the 1 st year post-extraction, and the volume of bone loss increased 40-60% in 3 years. 8 Conventional loading 10 is a predictable, dependable, safe, and accepted treatment modality that has been used as the main point of comparison for other dental implant loading protocols. 11 Recently, clinicians have increasingly begun to evaluate and examine the possibilities of shortening treatment periods either by earlier delivery of the implant-supported restoration or by placing implants in extraction sockets at the time of extraction. 2,3,12,13 Implant placement in fresh extraction sockets was first described by Schulte and Heimke, who referred to this procedure as immediate implant. 14 Several studies, for example, Yukna, 1991, Becker et al., 1998, 1999, Polizzi et al., 2000, and for example, Gelb, 1993, Watzek et al., 1995, Pecora et al., 1996, Goldstein et al., 2002, Cooper et al., 2014 reported high survival rates with this type of treatment The Advantages and Disadvantages of Immediate Implant Placement Several papers suggest that immediate implant placement may provide some advantages, such as, (i) Preventing bone resorption, (ii) maintaining alveolar crest width and height, (iii) reducing surgical procedures and treatment time, and finally, and (iv) good esthetic results, as the implant can be seated according to the natural tooth angulation and aligned with the adjacent teeth. 19,24-33 On the other hand, there are potential disadvantages of implants being placed in fresh extraction sockets, including, but not limited to the following:(i) Difficulty in controlling the final implant position, (ii) difficulty obtaining primary stability, (iii) inadequate soft tissue coverage, (iv) inability to inspect all aspects of the extraction socket for defects or infection, (v) osteotomy preparation difficulty due to bur movement (chatter) on the walls of the extraction site, and (vi) the additional cost of bone grafting. Since all the disadvantages listed are not present in every situation, any disadvantage may result in a compromised case. 25 One clinical and histological study compared histologic specimens of implants placed into fresh extraction sockets with those placed into mature healed bone. The investigators observed active secretion of osteoblasts in the coronal part of the alveolar crest; no signs of bone resorption were present in either specimen. Furthermore, there were no significant differences in the clinical and radiographic parameters noticed, suggesting that the degree of osseointegration does not differ between immediately placed implants and implants placed 632

2 periodontally compromised patients: A literature review AlQahtani NA into healed, mature bone. 32 Changes in crestal bone level were measured radiographically and several authors reported stable bone conditions and very little bone loss during up to 3 years of observation. 34,35 The Guidelines for Immediate Implant Placement The timing of implant placement has increased the debate, with the following new classification proposed at the Third ITI Consensus Conference, 13 and based on dimensional, morphologic, and histologic changes that follow tooth extraction: Type 1 - Immediate placement: A dental implant is placed immediately in an extraction socket with no healing of bone or soft tissues- Type 2 - Early placement (typically 4-8 weeks of healing) with some soft tissue healing: The post-extraction site has the alveolus covered by soft tissue but without significant bone healing- Type 3 - Early placement with partial bone healing (typically weeks of healing): The post-extraction site has a significant degree of bone healing and is covered by healed soft tissues- Type 4 - Late placement (more than 6 months after extraction): Implant placement in a fully healed edentulous site. The predictable restorative, functional, and esthetic success of implant-supported restoration resulted from the implant position in the bone. Bashutski and Wang (2007) proposed surgical guidelines for implant placement surgery. The implant should be placed at least 2 mm of the buccal bone, 3 mm apical to the cementoenamel junction of the adjacent teeth, and about 1.5 mm from the adjacent tooth root or 3 mm from the adjacent implant. Furthermore, the placement should be more toward the palate and more apically. 36 The Guidelines for Immediate Implant Loading Cochran et al., 2004, 10 recently published consensus statements and recommended clinical procedures regarding loading protocols for endosseous dental implants and promoting the following terms: 1. Immediate restoration (also known as immediate provisionalization): The restoration is delivered within 48 h of implant placement but no occlusal contact with the opposing dentition. 2. Immediate loading: The restoration is placed within 48 h of implant placement and is functionally in occlusal contact with the opposing dentition. 3. Early loading: The implant is restored with a fully functional restoration (in occlusion with opposing dentition) at a second stage procedure between 48 h and 3 months from the time of implant placement. 4. Conventional loading: The implant(s) is restored after a second stage procedure, 3-6 months after implant placement surgery. 5. Delayed loading: An implant-supported prosthesis is placed onto the implant(s) after a period longer than the conventional loading time (3-6 months). The Advantages of Immediate Implant Loading Immediate loading presents several other advantages when compared to conventional loading protocols. These include: 2,5,12, Overall reduction in treatment time 2. Reduction in the alveolar ridge resorption 3. An immediate, esthetic and/or pleasing restorative solution 4. Psychological, resulting in increased patient acceptance 5. Quicker solution to return to function 6. Avoidance of a removable prosthesis that may disturb the healing 7. Superiority of soft tissue profile when utilizing both the immediate implant placement with immediate loading 8. Reduced surgical interventions. Immediate implant placement indications and contraindications Evaluation of smile line, bone architecture, gingival biotype, and hard and soft tissue levels are crucial and essential for implant esthetics. 45,46 Kois emphasized five diagnostic keys for predictable, single-tooth, peri-implant esthetics when immediately placing implants in fresh extraction sockets. They are: 1. Tooth position and its relation to the gingival margin 2. Form of the periodontium 3. Gingival biotype 4. Shape of the tooth 5. Position of the bone crest before tooth extraction. Three of the five diagnostic keys involve hard and soft tissue components. 46 Consequently, when considering immediate implant placement, a careful analysis of the addressed factors is crucial for determining if the patient has the right diagnostic keys to allow for long-term success. A surgical approach for an immediate and conventional implant placement is almost similar except that in immediate implant placement; a possibility of implant shift toward the buccal side should be taken into consideration and certain clinical precautionary measures taken. 47 This is due to a thin buccal plate with a high content of bundle bone and the nature of self-tapping implants that in current use. 48 It is essential to understand the hard and soft tissues surrounding the surgical area in order to appropriately select cases for which immediate implant placement would be successful. Gingival biotype affects the periodontal tissue dimensions, including biologic width and masticatory mucosa. 45 Thick gingival biotype is defined when the periodontal probe cannot be seen through gingival tissues, whereas it is visible in thin biotypes. 49 A thick biotype is resilient and more prone to the 633

3 pocket formation, whereas gingival recession may happen due to thin biotype after mechanical or surgical manipulation. 50,51 This concept plays an important role for peri-implant tissues; when peri-implant soft tissue has a thick biotype, there are greater peri-implant mucosal dimensions. 45 Patients with thick biotypes are better candidates for immediate implant placement because they usually have a wide zone of keratinized gingiva. As a result, there is less chance that the tissues will recede post-placement, resulting in stable esthetics. If immediate placement is done in patients with a thin biotype, then there may be a high risk of exposing the metal margin of the implant because of minimum zones of keratinized gingiva and highly scalloped osseous contours. Furthermore, a thin tissue biotype has a higher frequency for the gingival recession of 1 mm compared with thick biotypes. Sites with immediate implants placement reported that 50% of the original buccal plate width underwent resorption. 52,53 Therefore, the immediate implant is often not recommended in areas with thin gingival biotype due to the above concerns. 47 A sufficient amount of osseous crest ridge, with a width of 4-5 mm and height of 10 mm or more are considered the minimal requirements for predictable immediate implant placement. The height is necessary for the primary stability of the implant and maintenance of a safe distance from vital anatomical structures (maxillary sinus, nasal floor, mandibular canal, or mental foramen). The distance from the alveolar crest to the future prosthesis contact point should be 5 mm or less to ensure the appearance of dental implants papillae. 54 Regarding the immediate placement approach, the ideal extraction socket should present little or no periodontal bone loss. Some authors agree that immediate placement of implants into a chronic infection socket is a major concern. For example, based on clinical observations, Tolman and Keller reported that immediate placement is contraindicated in the presence of periapical lesions. 55 Marcaccini et al. reported implants placed in patients who have periodontally infected sites initially healed slower, but were no different after 3 months. 56 However, implants immediately placed in sites with chronic periapical lesions could still attain a successful outcome similar to uninfected sites. 57,58 Novaes et al., reported periapical infection might not be contraindicated if the socket is debrided and disinfected properly. 59 A critical post-operative protocol needs to be followed. This protocol includes antibiotic administration, meticulous curettage and complete alveolarwall debridement before implant insertion. 57 Currently, it is agreed that implants can be successfully placed immediately at the time of extraction in periapically-infected sites as long as the socket is debrided, the infection removed and implant primary stability attained. 60 Funato et al. created a classification indicating or contraindicating immediate implant placement based on the characteristics of buccal bone and soft tissue profile. This classification provided the proper guidelines for immediate implant placement and timing between extraction and implant placement: 60 Class 1 has an intact buccal bone with thick biotype; for optimal results, immediate placement without flap reflection should be considered. Class 2 has an intact buccal bone with thin biotype; for good results, immediate placement with connective tissue graft procedure should be considered. Class 3 has buccal bone deficiency within the alveolar housing; immediate placement with guided bone regeneration (GBR), plus connective tissue graft, will result in a limited and acceptable result. Class 4 has buccal bone deficiency deviating from the alveolar housing; immediate placement is not indicated, and unacceptable, delayed approach is recommended. This classification system supports the idea that case selection is critical for determining whether immediate implant placement should be considered, and the importance of hard and soft tissue parameters in this selection. In general, immediate implant placement can be challenging due to the hard and soft tissue healing is unpredictable. Cases should be selected carefully to avoid treatment failures and esthetic complications. Furthermore, explaining the risks, benefits, and limitations of immediate implant placement with patients is important to avoid any future misunderstanding. GBR around immediate implant GBR can be used to manage the exposure of the implant surface due to the incongruity between the implant diameter and the morphology of the alveolus. In this situation, a regenerative barrier is applied, and primary closure of soft tissues is considered a prerequisite to the success of the GBR process. Although there are contrasting opinions about the necessity of primary closure in GBR, most authors agree that primary closure is very crucial and at least a goal that a clinician should consider in GBR. 61 Important to the procedure is that, after installing the immediate implant, the flap edges are approximated and the socket is passively (without tension) closed. Tension must be avoided, as it may lead to ischemia and flap necrosis, and increases the likelihood of barrier exposure with the associated infection, bone loss and even implant failure. When flap closure is not possible, the use of relaxing incisions, or rotated pedicle flaps, or a combination of them should be considered to reduce tension and increase flap manipulation. The relaxing incisions are either vertical full thickness or horizontal releasing incision of the periosteum. In the pedicle flap technique, the anterior part of the flap is dissected to separate a mucosal layer from the underlying periosteum using a split-thickness incision (pedicle flap). 22,62 Then, the pedicle layer is rotated laterally to cover the immediately placed implant. Horizontal mattress sutures are recommended to close the wound. However, soft tissue closure should be modified depending on the region where the implant is placed. On occasions, gingival grafts or split thickness connective tissue grafts may be utilized. 63,64 Becker et al. used non-resorbable expanded polytetrafluoroethylene (e-ptfe) membranes for GBR around immediate implants 634

4 periodontally compromised patients: A literature review AlQahtani NA and reported an incidence of 40% wound dehiscence necessitating premature membrane removal in an additional surgery. The frequent occurrence of membrane exposures in immediate implant placements was probably caused by inadequate primary wound closure. 65 Several authors reported incomplete bone regeneration in cases of early membrane exposure associated with signs of inflammation. 66,67 To avoid all these disadvantages, resorbable membranes were introduced and compared with the conventional e-ptfe-material. Zitzmann et al., comparing the defect fill utilizing the collagen membrane Bio-Gide A and the Gore-Tex barrier, reported a mean defect reduction of 92% and 78%, respectively. Using absorbable collagen membrane, the occurrence of wound dehiscence did not lead to an adverse clinical reaction in the surrounding soft tissues. However, premature degradation of the collagen membrane in the exposed area was reported, resulting in a shortened barrier function of the Bio-Gide membrane with reduced bone fill (87%), compared to areas without wound dehiscence (94% bone fill). 68 In another study of 1925 immediate implants, performed between 1988 and 2004, mineralized freeze-dried bone allograft with an absorbable barrier was utilized to cover exposed implant threads. They retrospectively reviewed the charts and reported a 1-16 years survival rate of 96%, with a failure rate of 3.7% pre-restoration and 0.3% post-restoration. 69 Gelb (1993) mentioned another factor influencing the success of bone regeneration by describing the defect morphology and distinguished among no-wall, 3-wall, and circumferential defects. He covered the exposed implant surfaces with or without bone grafting material and/or membrane, depending on the residual bony walls surrounding the defect. 20 Apart from factors such as wound dehiscence with membrane exposure and defect morphology, no other factors have, according to the literature, been mentioned to determine the amount of bone fill achieved when using GBR techniques around implants. Poor bone quality in the maxilla and cigarette smoking have been reported as complicating factors in relation to a higher number of implant failures On the other hand, Chen et al. conducted a prospective study and compared five groups in which patients received an immediate implant, randomly received 1 of 5 augmentation treatments and were submerged with connective tissue grafts: Group 1 e-ptfe membrane only, Group 2 resorbable polylactide/polyglycolide copolymer membrane only, Group 3 resorbable membrane and autogenous bone graft, Group 4 autogenous bone graft only, and Group 5 no membrane and no bone graft as control group. His results showed that defects adjacent to immediate implants might heal predictably without the use of membranes and/or bone grafts. 73 Finally, most authors agree that primary closure is one of the important factors that clinicians should consider in GBR. The use of a non-resorbable membrane or a resorbable allogenic material around immediate implants can provide predictable results in the long term. The use of grafts under barrier membranes in immediate implantation is a clinical judgment, and most studies indicate the superiority of combining bone grafts with barriers over the single use of either of them. 74 Esthetics is not only about harmonizing the size, shape, position, and color of each prosthesis with the adjacent teeth. 75 It is also essential to establish peri-implant soft tissue compatibility with the surrounding gingiva and mucosa. 76 Hence, the contralateral natural tooth may be considered the ultimate reference, especially in the anterior teeth. All morphometric differences in papilla levels, midfacial soft tissue levels, and crown parameters have been used to assess the esthetic outcome of single implant treatment. 77,78 Obvious advantages of immediate implant placement include, in addition to what was mentioned previously, potentially superior esthetics since hard and soft tissues have not fully remodeled yet. At least with respect to the midfacial soft tissue level, Schropp et al. described the ideal clinical crown length in significantly more cases following early placement when compared with conventional placement. 79 While a recent systematic review showed the lack of comparative studies with thorough esthetic analyses by clinicians and patients, it remains unclear whether single implant placement in healing sites of the anterior maxilla yields superior esthetic treatment outcome when compared with healed sites. 80 Immediate implant in periodontally compromised patients Historically, many studies showed that patients previously treated for periodontitis were at a higher risk of developing peri-implantitis and implant loss compared with periodontally healthy patients. 81 Thus, it was suggested that periodontitis still persists, even after tooth extraction, and it may impact the survival rate and long-term prognosis of dental implants Good results have been documented with early implant function after insertion in fresh extraction sockets of periodontally compromised teeth at 1-year follow-ups, with high survival rates (100%) and low marginal bone loss ( mm) when requiring high-implant stability and low inflammation during surgical and post-surgical treatment. 85 These recent studies suggest that the immediate implants placed in immediate function in patients with a history of the periodontal disease may be viable; this surgical protocol is used to control the inflammatory response. While several studies have reported the success of immediate placement in periodontally compromised patients, clinical documentation of the long-term survival of these implants is still lacking. Conclusion The placement of implants immediately in fresh sockets with immediate loading in periodontally compromised patients is a promising treatment modality, but the practitioner should follow a very strict protocol. Further long-term research is 635

5 required to prove the predictability of utilizing GBR around immediate implants with immediate loading in periodontally compromised patients. References 1. Brånemark PI, Hansson BO, Adell R, Breine U, Lindström J, Hallén O, et al. Osseointegrated implants in the treatment of the edentulous jaw. Experience from a 10-year period. Scand J Plast Reconstr Surg Suppl 1977;16: Wang HL, Boyapati L. PASS principles for predictable bone regeneration. Implant Dent 2006;15(1): Chiapasco M. Early and immediate restoration and loading of implants in completely edentulous patients. Int J Oral Maxillofac Implants 2004;19 Suppl: Misch CE, Wang HL, Misch CM, Sharawy M, Lemons J, Judy KW. Rationale for the application of immediate load in implant dentistry: Part I. Implant Dent 2004;13(3): Misch CE, Wang HL, Misch CM, Sharawy M, Lemons J, Judy KW. Rationale for the application of immediate load in implant dentistry: Part II. Implant Dent 2004;13(4): Tarnow DP, Emtiaz S, Classi A. Immediate loading of threaded implants at stage 1 surgery in edentulous arches: Ten consecutive case reports with 1- to 5-year data. Int J Oral Maxillofac Implants 1997;12(3): Brånemark PI. Osseointegration and its experimental background. J Prosthet Dent 1983;50(3): Carlsson GE, Bergman B, Hedegård B. Changes in contour of the maxillary alveolar process under immediate dentures. A longitudinal clinical and x-ray cephalometric study covering 5 years. Acta Odontol Scand 1967;25(1): Schulte W, Kleineikenscheidt H, Lindner K, Schareyka R. The Tübingen immediate implant in clinical studies. Dtsch Zahnarztl Z 1978;33(5): Cochran DL, Morton D, Weber HP. Consensus statements and recommended clinical procedures regarding loading protocols for endosseous dental implants. Int J oral Maxillofac Implants 2004;19 Suppl: Degidi M, Piattelli A, Gehrke P, Felice P, Carinci F. Fiveyear outcome of 111 immediate nonfunctional single restorations. J Oral Implantol 2006;32(6): Schwartz-Arad D, Levin L. Symphysis revisited: Clinical and histologic evaluation of newly formed bone and reharvesting potential of previously used symphysial donor sites for onlay bone grafting. J Periodontol 2009;80(5): Hämmerle CH, Chen ST, Wilson TG Jr. Consensus statements and recommended clinical procedures regarding the placement of implants in extraction sockets. Int J Oral Maxillofac Implants 2004;19 Suppl: Schulte W, Heimke G. The Tübinger immediate implant. Quintessenz 1976;27(6): Yukna RA. Clinical comparison of hydroxyapatite-coated titanium dental implants placed in fresh extraction sockets and healed sites. J Periodontol 1991;62(7): Becker BE, Becker W, Ricci A, Geurs N. A prospective clinical trial of endosseous screw-shaped implants placed at the time of tooth extraction without augmentation. J Periodontol 1998;69(8): Becker W, Dahlin C, Lekholm U, Bergstrom C, van Steenberghe D, Higuchi K, et al. Five-year evaluation of implants placed at extraction and with dehiscences and fenestration defects augmented with eptfe membranes: Results from a prospective multicenter study. Clin Implant Dent Relat Res 1999;1(1): Polizzi G, Grunder U, Goené R, Hatano N, Henry P, Jackson WJ, et al. Immediate and delayed implant placement into extraction sockets: A 5-year report. Clin Implant Dent Relat Res 2000;2(2): Gelb DA. Immediate implant surgery: Three-year retrospective evaluation of 50 consecutive cases. Int J Oral Maxillofac Implants 1993;8(4): Watzek G, Haider R, Mensdorff-Pouilly N, Haas R. Immediate and delayed implantation for complete restoration of the jaw following extraction of all residual teeth: A retrospective study comparing different types of serial immediate implantation. Int J Oral Maxillofac Implants 1995;10(5): Pecora G, Andreana S, Covani U, De Leonardis D, Schifferle RE. New directions in surgical endodontics; Immediate implantation into an extraction site. J Endod 1996;22(3): Goldstein M, Boyan BD, Schwartz Z. The palatal advanced flap: A pedicle flap for primary coverage of immediately placed implants. Clin Oral Implants Res 2002;13(6): Cooper LF, Reside G, Raes F, Garriga JS, Tarrida LG, Wiltfang J, et al. Immediate provisionalization of dental implants in grafted alveolar ridges in the esthetic zone: A 5-year evaluation. Int J Periodontics Restorative Dent 2014;34(4): Rosenquist B, Grenthe B. Immediate placement of implants into extraction sockets: Implant survival. Int J Oral Maxillofac Implants 1996;11(2): Schwartz-Arad D, Chaushu G. The ways and wherefores of immediate placement of implants into fresh extraction sites: A literature review. J Periodontol 1997;68(10): Wilson TG Jr, Schenk R, Buser D, Cochran D. Implants placed in immediate extraction sites: A report of histologic and histometric analyses of human biopsies. Int J Oral Maxillofac Implants 1998;13(3): Cornelini R, Scarano A, Covani U, Petrone G, Piattelli A. Immediate one-stage postextraction implant: A human clinical and histologic case report. Int J Oral Maxillofac Implants 2000;15(3): Kan JY, Rungcharassaeng K. Immediate placement and provisionalization of maxillary anterior single implants: A surgical and prosthodontic rationale. Pract Periodontics Aesthet Dent 2000;12(9): Rosenquist B, Ahmed M. The immediate replacement of teeth by dental implants using homologous bone membranes to seal the sockets: Clinical and radiographic 636

6 periodontally compromised patients: A literature review AlQahtani NA findings. Clin Oral Implants Res 2000;11(6): Schwartz-Arad D, Gulayev N, Chaushu G. Immediate versus non-immediate implantation for full-arch fixed reconstruction following extraction of all residual teeth: A retrospective comparative study. J Periodontol 2000;71(6): Chaushu G, Chaushu S, Tzohar A, Dayan D. Immediate loading of single-tooth implants: Immediate versus nonimmediate implantation. A clinical report. Int J Oral Maxillofac Implants 2001;16(2): Paolantonio M, Dolci M, Scarano A, d Archivio D, di Placido G, Tumini V, et al. Immediate implantation in fresh extraction sockets. A controlled clinical and histological study in man. J Periodontol 2001;72(11): Schultes G, Gaggl A. Histologic evaluation of immediate versus delayed placement of implants after tooth extraction. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2001;92(1): Crespi R, Capparé P, Gherlone E, Romanos GE. Immediate versus delayed loading of dental implants placed in fresh extraction sockets in the maxillary esthetic zone: A clinical comparative study. Int J Oral Maxillofac Implants 2008;23(4): Canullo L, Rasperini G. Preservation of peri-implant soft and hard tissues using platform switching of implants placed in immediate extraction sockets: A proof-ofconcept study with 12 - To 36-month follow-up. Int J Oral Maxillofac Implants 2007;22(6): Bashutski JD, Wang HL. Common implant esthetic complications. Implant Dent 2007;16(6): Avila G, Galindo P, Rios H, Wang HL. Immediate implant loading: Current status from available literature. Implant Dent 2007;16(3): Bhola M, Neely AL, Kolhatkar S. Immediate implant placement: Clinical decisions, advantages, and disadvantages. J Prosthodont 2008;17(7): Nordin T, Graf J, Frykholm A, Helldén L. Early functional loading of sand-blasted and acid-etched (SLA) Straumann implants following immediate placement in maxillary extraction sockets. Clinical and radiographic result. Clin Oral Implants Res 2007;18(4): Canullo L, Goglia G, Iurlaro G, Iannello G. Shortterm bone level observations associated with platform switching in immediately placed and restored single maxillary implants: A preliminary report. Int J Prosthodont 2009;22(3): Collaert B, De Bruyn H. Immediate functional loading of TiOblast dental implants in full-arch edentulous maxillae: A 3-year prospective study. Clin Oral Implants Res 2008;19(12): Mijiritsky E, Mardinger O, Mazor Z, Chaushu G. Immediate provisionalization of single-tooth implants in fresh-extraction sites at the maxillary esthetic zone: Up to 6 years of follow-up. Implant Dent 2009;18(4): Morton D, Jaffin R, Weber HP. Immediate restoration and loading of dental implants: Clinical considerations and protocols. Int J Oral Maxillofac Implants 2004;19 Suppl: Degidi M, Piattelli A. Comparative analysis study of 702 dental implants subjected to immediate functional loading and immediate nonfunctional loading to traditional healing periods with a follow-up of up to 24 months. Int J Oral Maxillofac Implants 2005;20(1): Kan JY, Rungcharassaeng K, Umezu K, Kois JC. Dimensions of peri-implant mucosa: An evaluation of maxillary anterior single implants in humans. J Periodontol 2003;74(4): Kois JC. Predictable single-tooth peri-implant esthetics: Five diagnostic keys. Compend Contin Educ Dent 2004;25(11):895-6, 898, Evans CD, Chen ST. Esthetic outcomes of immediate implant placements. Clin Oral Implants Res 2008;19(1): Araújo MG, Sukekava F, Wennström JL, Lindhe J. Tissue modeling following implant placement in fresh extraction sockets. Clin Oral Implants Res 2006;17(6): Kois JC. Predictable single tooth peri-implant esthetics: Five diagnostic keys. Compend Contin Educ Dent 2001;22(3): Müller HP, Heinecke A, Schaller N, Eger T. Masticatory mucosa in subjects with different periodontal phenotypes. J Clin Periodontol 2000;27(9): Sanavi F, Weisgold AS, Rose LF. Biologic width and its relation to periodontal biotypes. J Esthet Dent 1998;10(3): Gher ME, Quintero G, Assad D, Monaco E, Richardson AC. Bone grafting and guided bone regeneration for immediate dental implants in humans. J Periodontol 1994;65(9): Botticelli D, Berglundh T, Lindhe J. Hard-tissue alterations following immediate implant placement in extraction sites. J Clin Periodontol 2004;31(10): Tarnow D, Elian N, Fletcher P, Froum S, Magner A, Cho SC, et al. Vertical distance from the crest of bone to the height of the interproximal papilla between adjacent implants. J Periodontol 2003;74(12): Tolman DE, Keller EE. Endosseous implant placement immediately following dental extraction and alveoloplasty: Preliminary report with 6-year follow-up. Int J Oral Maxillofac Implants 1991;6(1): Marcaccini AM, Novaes AB Jr, Souza SL, Taba M Jr, Grisi MF. Immediate placement of implants into periodontally infected sites in dogs. Part 2: A fluorescence microscopy study. Int J Oral Maxillofac Implants 2003;18(6): Lindeboom JA, Tjiook Y, Kroon FH. Immediate placement of implants in periapical infected sites: A prospective randomized study in 50 patients. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;101(6): Novaes AB Jr, Novaes AB. Immediate implants placed into infected sites: A clinical report. Int J Oral Maxillofac 637

7 Implants 1995;10(5): Novaes AB Jr, Vidigal Júnior GM, Novaes AB, Grisi MF, Polloni S, Rosa A. Immediate implants placed into infected sites: A histomorphometric study in dogs. Int J Oral Maxillofac Implants 1998;13(3): Funato A, Salama MA, Ishikawa T, Garber DA, Salama H. Timing, positioning, and sequential staging in esthetic implant therapy: A four-dimensional perspective. Int J Periodontics Restorative Dent 2007;27(4): Fugazzotto PA. Maintenance of soft tissue closure following guided bone regeneration: Technical considerations and report of 723 cases. J Periodontol 1999;70(9): Edel A. The use of a connective tissue graft for closure over an immediate implant covered with occlusive membrane. Clin Oral Implants Res 1995;6(1): Bianchi AE, Sanfilippo F. Single-tooth replacement by immediate implant and connective tissue graft: A 1-9-year clinical evaluation. Clin Oral Implants Res 2004;15(3): Evian CI, Cutler S. Autogenous gingival grafts as epithelial barriers for immediate implants: Case reports. J Periodontol 1994;65(3): Becker W, Dahlin C, Becker BE, Lekholm U, van Steenberghe D, Higuchi K, et al. The use of e-ptfe barrier membranes for bone promotion around titanium implants placed into extraction sockets: A prospective multicenter study. Int J Oral Maxillofac Implants 1994;9(1): Simion M, Baldoni M, Rossi P, Zaffe D. A comparative study of the effectiveness of e-ptfe membranes with and without early exposure during the healing period. Int J Periodontics Restorative Dent 1994;14(2): Nowzari H, Slots J. Microbiologic and clinical study of polytetrafluoroethylene membranes for guided bone regeneration around implants. Int J Oral Maxillofac Implants 1995;10(1): Zitzmann NU, Naef R, Schärer P. Resorbable versus nonresorbable membranes in combination with Bio- Oss for guided bone regeneration. Int J Oral Maxillofac Implants 1997;12(6): Wagenberg B, Froum SJ. A retrospective study of 1925 consecutively placed immediate implants from 1988 to Int J Oral Maxillofac Implants 2006;21(1): Bain CA. Smoking and implant failure benefits of a smoking cessation protocol. Int J Oral Maxillofac Implants 1996;11(6): De Bruyn H, Collaert B. The effect of smoking on early implant failure. Clin Oral Implants Res 1994;5(4): Jaffin RA, Berman CL. The excessive loss of Branemark fixtures in type IV bone: A 5-year analysis. J Periodontol 1991;62(1): Chen ST, Darby IB, Adams GG, Reynolds EC A prospective clinical study of bone augmentation techniques at immediate implants. Clin Oral Implants Res 2005;16(2): El Helow K, El Askary Ael S. Regenerative barriers in immediate implant placement: A literature review. Implant Dent 2008;17(3): Moskowitz ME, Nayyar A. Determinants of dental esthetics: A rational for smile analysis and treatment. Compend Contin Educ Dent 1995;16(12):1164, Meijer HJ, Stellingsma K, Meijndert L, Raghoebar GM. A new index for rating aesthetics of implant-supported single crowns and adjacent soft tissues the implant crown aesthetic index. Clin Oral Implants Res 2005;16(6): Chang M, Wennström JL, Odman P, Andersson B. Implant supported single-tooth replacements compared to contralateral natural teeth. Crown and soft tissue dimensions. Clin Oral Implants Res 1999;10(3): Cosyn J, De Rouck T. Aesthetic outcome of single-tooth implant restorations following early implant placement and guided bone regeneration: Crown and soft tissue dimensions compared with contralateral teeth. Clin Oral Implants Res 2009;20(10): Schropp L, Isidor F, Kostopoulos L, Wenzel A. Interproximal papilla levels following early versus delayed placement of single-tooth implants: A controlled clinical trial. Int J Oral Maxillofac Implants 2005;20(5): den Hartog L, Slater JJ, Vissink A, Meijer HJ, Raghoebar GM. Treatment outcome of immediate, early and conventional single-tooth implants in the aesthetic zone: A systematic review to survival, bone level, soft-tissue, aesthetics and patient satisfaction. J Clin Periodontol 2008;35(12): Hardt CR, Gröndahl K, Lekholm U, Wennström JL. Outcome of implant therapy in relation to experienced loss of periodontal bone support: A retrospective 5 - Year study. Clin Oral Implants Res 2002;13(5): Karoussis IK, Salvi GE, Heitz-Mayfield LJ, Brägger U, Hämmerle CH, Lang NP. Long-term implant prognosis in patients with and without a history of chronic periodontitis: A 10-year prospective cohort study of the ITI dental implant system. Clin Oral Implants Res 2003;14(3): Evian CI, Emling R, Rosenberg ES, Waasdorp JA, W, Shah S, et al. Retrospective analysis of implant survival and the influence of periodontal disease and immediate placement on long-term results. Int J Oral Maxillofac Implants 2004;19(3): Villa R, Rangert B. Early loading of interforaminal implants immediately installed after extraction of teeth presenting endodontic and periodontal lesions. Clin Implant Dent Relat Res 2005;7 Suppl 1:S Cornelini R, Cangini F, Covani U, Wilson TG Jr. Immediate restoration of implants placed into fresh extraction sockets for single-tooth replacement: A prospective clinical study. Int J Periodontics Restorative Dent 2005;25(5):