The following criteria were considered in the process of selecting studies of immediate implant placement and restoration for this review:
1. Types of studies: all longitudinal studies were eligible for inclusion – randomized controlled trials, controlled clinical trials, cohort studies, case control studies and consecutive case report series. Only those studies that included 6 patients or more were selected. A minimum follow up time of 1 year was set as an inclusion criterion.
Only studies published in English were included.
2. Type of treatment modality (intervention): immediate implantation into the fresh extraction socket followed an immediate placement of a provisional restoration in the aesthetic zone.
3. Outcomes that were measured:
Implant survival rate.
Patient satisfaction.
Peri implant soft tissue changes.
Peri implant hard tissue changes.
Gingival biotype and its relation to recession.
For this review, a detailed search strategy was used for each selected database in order to identify all of the articles published in relation to the stated aims of this review. The search strategy used was a combination of free text terms and MeSH* terms. The searched data bases were:
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# PUB MED, EBSCOhost and Ovid arms of MEDLINE.
# CENTRAL (The Cochrane Central Registar of Controlled Trials).
# Science Direct.
The terms used in this search were:
Dental Implants, Oral Implants, immediate placement, immediate restoration, Immediate Provisionalization, aesthetic, single tooth replacement, single tooth in the maxilla and extraction socket.
The search strategy was as follows:
(Single Tooth* OR teeth*) AND Maxilla* AND (Immediate OR Immediate placement, OR Immediate Implantation, OR immediate restoration, OR extraction socket)
Single Tooth* AND Maxilla* AND Single Tooth* AND maxilla * AND
Single Tooth* AND Maxilla* AND (OR provisionalization) Single Tooth* AND Maxilla* AND
Furthermore, the search was complemented by checking the references of the selected articles for additional useful publications. Also a manual search was carried out of the following major journals in dental implantology: International Journal of Oral and Maxillofacial Implants, Clinical Oral Implants Research, Clinical Implant Dentistry and Related Research.
The search strategy initially yielded 80 articles. From these, 17 articles were considered
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to fulfil the criteria for inclusion in this review. The other studies were excluded for the following reasons:
1) Review articles (10 articles): [35], [36], [37], [38], [39], [40], [41], [42], [43] and [44].
2) Implantation into healed sockets only (30 articles ): [45], [46], [47], [48], [49], [50], [51], [52], [53], [54], [55], [56], [57], [58], [59], [60], [61], [62], [63], [64], [65] , [66], [67] , [68], [69], [70], [71], [72], [73] and [74].
3) Implantation in the mandible or maxilla without any differentiation (7 articles): [45], [46], [52], [56], [59], [74] and [75].
4) Case reports of immediately placed and loaded implants (16 articles): [45], [47], [50], [52], [53], [59], [76], [77], [78], [79], [80], [81], [82], [83], [84], and [85].
5) The 17 included articles, alongside a description of the study type, implant system used and the numbers of included patients/implants are outlined in Table 1.
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*Delayed implant placement.
RCT, randomized controlled trial; CS, case series.
Table 1 Selected studies reporting on immediately placed and provisionally restored single maxillary implants in the aesthetic zone.
Study Design No. of
Patient/implant
Implant systems
Wohrle 12 (1998) CS 14/ 14 Replace Select
Hui et al 13 (2001) CS 24/ 24 = 13 & 11* Brồnemark
Guirado et al 14 (2002) CS 13/ 18 = 9& 9* Osseotite 3i
Chaushu et al 15 (2001) CS 26/28= 14 & 8* 21 Steri-Oss & 7 Alpha Bio
Groisman et al 86 (2003) CS 92/ 92 Replace select
Kan et al 87 (2003) CS 35/ 35 Replace Select
Lorenzoni et al 88 (2003) CS 9/ 12 =8 & 4* Frialit-2
Norton 89 (2004) CS 25/ 28 =16 & 12* Astra Tech
Tsirlis 90 (2005) CS 38/ 43 =28 & 15* Osseotite 3i
Cornelini et al 91 (2005) CS 22/ 22 ITI
Ferrarra et al 92 (2006) CS 33/ 33 Frialit-2
Kan et al 93 (2007) CS 29/ 38 = 23 &15* Replace Select
Canullo et al 94 (2007) CS 9/ 10 Defcon®
Hall et al 95 (2007) RCT 28/ 28 =14& 14* Southern Implants Palattella et al 96 (2008) CS 16/ 18 = 9& 9* Tapered effect
De Rouck et al 97 (2008) CS 30/ 30 Replace select
Ribeiro et al 98 (2008) CS 64/82= 46 & 36* Connexao sistema de protese
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2.5-1 Survival rate of immediately placed and restored implants in the aesthetic zone
The term ‘implant survival rate’ is defined as the percentage of implants that present at follow up [99], although it is important to note that the status of the implant not specified [100]. Conversely, implant success is defined as the presence of the implant at the end of an observation period, along with the absence of progressive bone loss, radiolucency, mobility (clinically), pain, discomfort and/or neuro-sensory changes [101].
All studies selected for this review reported on the survival rates of immediate implant placement and restoration in the aesthetic zone. A review of these studies in relation to the implant survival outcome is presented in this part of the review.
The primary goal of Wohrle‘s (1988) investigation was to predictably maintain soft tissue morphology in the aesthetic zone of the maxilla and avoid postextraction complications related to hard tissue resorption and soft tissue recession. Fourteen implants were placed in fourteen consecutive patients (14/14). Five of the implants were placed in the lateral incisor position and the other nine were placed in the central incisor position. The implant system used was Replace (Steri-Oss, Yorba Linda, CA, USA) and both screw-type cylindrical and screw-type tapered implants were used. All surgical and prosthetic procedures were carried out by the same clinician. None of the implants were lost with an overall survival rate of 100% in a follow-up period ranging from six to 36 months [12]. In 2001, Hui et al [13]
proposed immediate placement and restoration as a treatment modality aimed at provide an immediate and cost effective solution for restoring a single missing tooth in the maxillary aesthetic region. This prospective clinical investigation included twenty-four participants,
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thirteen of which had immediate implant placement and restoration while eleven received implants in healed sites. All of the implants were placed in the maxillary aesthetic region.
The overall follow-up period ranged from one to 15 months. According to the authors, the desirable goals of patient satisfaction, good aesthetic outcome and reduced treatment cost were achieved in this treatment protocol. The implant system used was Brồnemark (Nobel Biocare AB, Gửteborg, Sweden), and the implant types were both screw-type tapered and cylindrical. The implant survival rate of this study was 100% within the reported one to 15 months period of follow-up for both groups.
Guirado et al [14] conducted a prospective study involving eighteen implants in thirteen patients using the Osseotite system (3i, Implant Innovation, USA). All of the implants were placed in the maxillary aesthetic zone with nine placed into fresh extraction sockets and nine into healed sites. The observation period was one year and a 100% implant survival rate was reported. Advantages associated with the one stage protocol included immediate aesthetics, comfort and no need for surgical re-entry. Furthermore, the interdental papilla adjacent to the implants were preserved leading to optimal aesthetic results. The author concluded that the placement of implants immediately into fresh extraction sockets was a viable and predictable treatment alternative associated with a high survival rate.
Chaushu et al [15] hypothesised that the immediate restoration of implants replacing single missing teeth could be successfully achieved following immediate implant placement into fresh extraction sockets, as well as healed sockets. This study included twenty-six consecutive patients who received twenty-eight implants. Nineteen implants were placed into fresh extraction sites, and nine were placed into healed sites. The two implant systems used in this study were Steri-Oss, (Yorba Linda, CA, USA), (21 implants) and Alpha Bio hydroxy-
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apatite coated cylindrical implants, (7 implants). The follow-up period ranged from six to 18 months, with a mean of 13 months for the immediately placed implants and 16.4 months for implants placed into healed sites. There were three failures among the immediately placed and restored implants, all occurring during the first month following implantation, resulting in an overall survival rate of 82.4% for this group. The patients who lost their implants were over 50 years of age. In each of these patients there was initial discomfort, followed by moderate pain and implant mobility. Another two patients experienced swelling with a purulent exudate. On the other hand, all of the non-immediate implants survived the healing period without any loss leading to a 100% short term survival rate for this group. All surviving implants of both groups were free from any complications. The results of this study revealed a 100% success rate in the healed sites but about a 20% failure rate associated with immediate placement into extraction sites. The use of a press fit cylindrical implant type may explain in part the low success rate in the immediate group.
In another prospective clinical study carried out by Kan et al [87] the implant survival rate, peri-implant tissue response, aesthetic outcomes and patient satisfaction were evaluated.
This study included thirty-five patients with a mean age of 36.5 years, and each patient received a single flat platform, screw type tapered implant (Replace, Nobel Biocare, Yorba Linda, CA, USA). All of the implants were placed into fresh extraction sockets. The implant survival rate was 100% after a follow-up period of one year. All of the patients were satisfied with the aesthetic outcome of their restorations. The author concluded that a favourable implant success rate, peri-implant tissue response and aesthetic outcome can be achieved with immediately restored single implants placed in the maxillary aesthetic zone. In a more recent investigation with similar aims, the same author conducted another study, but instead of using flat platform implants, a scalloped implant platform design was used [93]. The introduction
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of this new platform design aimed to replicate the irregular bony topography which results after tooth extraction, thus preventing future bone loss. The implant system used was (Nobel perfect; Nobel Biocare, USA). Thirty-eight implants were placed in twenty-nine patients with a mean age of 45.1 years. Fifteen implants were placed into healed sites while the other twenty-three were placed into fresh extraction sites. At the one year follow-up all implants remained in function with an overall survival rate of 100%.
The stated purpose of Groisman‘s study [86] was to evaluate the survival rate of ninety- two tapered implants which were immediately placed and restored in the maxillary aesthetic region. The diameter of the inserted implants was selected based upon the size of the tooth sockets (Nobel Biocare, Yorba Linda, CA, USA). The observation period was two years, but only ten implants were followed up for the full 24 months. At the conclusion of the follow up period, 6 implants had been lost resulting in an overall implant survival rate of 93.5%.
According to the author, one implant was lost due to trauma and two others due to overload in patients with a deep overbite. The cause of failure for the other three implants was not described. The study concluded that immediately placed and restored tapered implants did not show any adverse effects with regards to osseointegration. Favourable aesthetic outcome was achieved in eighty-two of 92 cases, representing 89% of the total number.
Lorenzoni et al [88] evaluated the clinical outcomes of immediately placed and restored stepped-screw type grit-blasted, acid etched FRIALIT-2 Synchro implants one year after placement in the maxillary anterior region. In the course of this study, nine patients received 12 implants; eight of which were placed into fresh extraction sites and four were placed into healed sites. All implants were immediately restored with acrylic resin provisional crowns,
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and patients provided with occlusal splints so that the restorations were free from any direct loading. No implants failed in the 12 months after insertion, resulting in a 100% survival rate.
Norton [89] evaluated the clinical outcome of single-tooth immediately restored implants placed in the upper arch. Twenty-five consecutive patients with a mean age of 48.2 years received twenty-eight Astra Tech ST implants (Lexington, MA). Sixteen of the implants were placed into fresh extraction sockets while the rest were placed into healed sites. The follow- up period ranged from twelve to thirty months. All patients received friction-fit temporary crowns instead of cemented crowns. After a mean duration of four and half months following the surgical procedure, the permanent crowns were placed. Implant survival, along with hard and soft tissue changes, was recorded at follow up with an overall survival rate of 96.4%.
One patient, a heavy smoker, lost one implant within one month of surgical placement.
Furthermore, unfavourable soft tissue recession was associated with one implant. However, most of the restorations maintained an aesthetic gingival contour and architecture. Eleven of the 28 provisional restorations needed further treatment; six required replacement during the temporization period and five required re-cementation after becoming loose. The study concluded that immediate temporization of maxillary single-tooth implants could be both safe and predictable and the procedure appeared to yield favourable soft tissue aesthetic outcomes.
The authors concluded that this treatment protocol utilizing the Astra Tech ST implant system resulted in predictable outcomes following immediate implant placement and restoration with provisional acrylic resin crowns.
In a study using two different implant systems, NT Osseotite (3i Implant Innovations Inc) implants and Frialit-2 (Friatec AG, Mannheim- Germany), forty-three single implants were inserted in thirty-eight patients. A survival rate of 100% was reported following an
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observation period of 24 months. The patients were divided into two groups, immediate and delayed implant installation. The first group received twenty-eight immediately placed implants while the rest of the patients received delayed implant placement [90].
In another study using the Straumann TE implant system (Institute Straumann AG, Waldenburg, Switzerland), twenty-two single implants were immediately restored and followed up for one year. Three of these implants were placed into healed sockets while the rest were placed immediately into fresh extraction sockets [91]. The temporary crowns were completely out of occlusion in both centric and eccentric positions. Screw-retained temporary crowns were constructed to avoid the use of adhesive cements which may interfere with the healing process during osseointegration [16]. Nineteen of the implants were placed in the maxilla and three in the mandible. Premolars were the most common teeth to be replaced (13 teeth), followed by central incisors (6 teeth) and lateral incisors (3 teeth). The study reported a survival rate of 100%. All the implants were successful according to the criteria of Smith and Zarb[101]. Within the limits of this investigation, immediate restoration of single-tooth implants placed in fresh extraction sockets was considered to be an acceptable option.
In a study conducted by Ferrara et al [92], thirty-three consecutive patients with a mean age of 41 years received a single implant supported crown to replace a missing maxillary tooth at the time of tooth extraction. The implant system used was Frialit-2 (Friatec AG, Mannheim- Germany). Thirteen central incisors, nine lateral incisors, four canines and seven first premolars were included. The follow-up period ranged from one to four years. There were two implant failures resulting in an overall success rate of 93.9%. One implant did not integrate while another one became unstable as a result of trauma.
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Canullo and Rasperini [94] investigated immediately placed and restored implants using the TSATM series 5 Defcon® Impladent (Barcelona, Spain) system. A platform switching design, whereby the trans-mucosal abutment was narrower than the implant platform, was used in order to maintain the surrounding peri-implant tissue dimensions. Ten 6 mm diameter implants were immediately placed into fresh extraction sockets in the aesthetic zone of the maxilla. A provisional 4 mm diameter trans-mucosal abutment was subsequently connected to the implant body, and a provisional crown was adapted and adjusted for non-occlusal contact in centric as well as eccentric positions. The definitive restoration was completed three months following implant placement. Nine patients with 10 sites were treated and the follow- up period was 22 months. All 10 implants were found to be clinically osseointegrated with a 100% survival rate.
Hall et al [95] evaluated the use of immediately placed and temporized tapered implants (Southern Implants Ltd, Irene, South Africa) to replace single teeth in the anterior maxilla.
The participants’ mean ages were 43.25 years and the implants were followed up for one year.
The patients were randomly divided into conventional (control group = 14 patients) and immediate restoration groups (test group = 14 patients). The test implants received provisional screw-retained crowns within four hours of implant placement, while in the conventional restoration group; temporary crowns were placed after 26 weeks. In the immediate placement/restoration group, one implant was lost for an overall survival rate of 93%, while in the control group two implants were lost at the one year follow-up. This investigation concluded that the immediate placement and restoration protocol used in this study resulted in similar outcomes as conventionally restored implants.
The main aim of Palattella‘s study [96] was to compare the immediate restoration of
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implants placed using an immediate and a delayed placement protocol. Sixteen patients with a mean age of 35 years were treated for single-tooth substitution in the anterior maxilla. The patient population was randomly divided into two groups. In the first group (test group), eight patients received nine implants placed and restored at the time of tooth extraction. The second group (control group) of eight patients received nine implants placed eight weeks after tooth removal. All implants underwent immediate restoration. All patients received the same implant system in the form of tapered effect (TE) Straumann implants (Institute Straumann AG, Waldenburg, Switzerland). Marginal bone resorption, papilla index and the position of mucosal margin were assessed at the time of provisional restoration fabrication (within 48 hours after implant placement) and at a two year follow-up visit. No implants were lost, resulting in a 100% survival rate for both groups after twenty-four months. The results suggest that immediate implant placement and restoration without functional loading may be considered a valuable therapeutic option for selected cases of single-tooth replacement in the aesthetic area.
A recent study conducted by De Rouck [97] also evaluated implant survival rates, soft and hard tissue changes and patient satisfaction in relation to immediately placed and restored implants in the anterior maxilla. Thirty consecutive patients underwent the same treatment protocol which consisted of flap elevation followed by immediate implant placement and connection of a screw-retained provisional restoration. The implant system used was Nobel Replace Tapered (Nobel Biocare, Goteborg, Sweden). Clinical and radiographic assessments were carried out at 1, 3, 6 and 12 monthly intervals. The results revealed that one implant failed in the first month of follow up resulting in a survival rate of 97%. It was concluded that this particular protocol can be considered to be a valuable treatment modality in carefully selected patients.
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Ribeiro et al [98] compared immediately placed implants with those placed into healed sockets. Eighty-two implants were placed in the maxilla of forty-six patients, with forty-six implants inserted using the immediate placement protocol while the other thirty-six were inserted using the delayed placement protocol. The implant system used for this investigation was Conexao Sistema (de Protese Ltda, Sao Paulo, SP, Brazil). Success of implant integration was assessed according to the criteria described by Albrektsson [102]. The follow-up period ranged from 18 to 39.7 months. Three of the implants from the immediate placement group failed, resulting in a survival rate of a 93.5%. The delayed placement group had an overall success rate of 100 %. The differences in survival rate between the two groups were not statistically significant [98].
Summary and conclusion:
Table 2 shows the results of studies which investigated the survival rate of immediately placed and restored implants in the aesthetic zone. An implant survival rate of 100% was described in all except five studies, namely, Chaushu et al [15] achieved osseointegration in 78.6% of the cases while Groisman [86] achieved 93.5% and Ferrara et al [92] reported 93.9%. In two other recent studies, the reported implant survival rates were 93% and 97% respectively [95, 97]. Therefore, the majority of the studies reported that the implant survival rate following immediate placement and restoration is comparable to that achieved using conventional therapy.
Based on the results of studies carried out over relatively short time periods, the replacement of single teeth in the maxillary aesthetic region can be predictably achieved using an immediate implant placement and restoration protocol. However, studies with a