Dental implant placement into fresh extraction sockets

indexImmediate placement of dental implants into fresh extraction sockets has for some time been an established surgical technique. The theory is that it preserves alveolar ridge, reduces morbidity, and is more acceptable to the patient. However, there may also be disadvantages such as reduced implant survival, unfavourable changes in the hard/soft tissue and extended treatment times. To standardise the type of implant placement they have been classified into four types:


  • Immediate placement (type 1).
  • Early placement with soft tissue healing (type 2).
  • Early placement with partial bone healing (type 3).
  • Late placement (type 4).

The research question for this systematic review and meta-analysis was: ‘‘Do immediately inserted implants perform similarly to implants that are inserted into a healed socket?’’


This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and registered with PROSPERO.

The population (P) was patients who had undergone osseointegrated implant insertion into fresh extraction sockets (I) or healed sockets (C). The primary outcome (O) evaluated was implant survival rate. Marginal bone loss, primary implant stability, and soft tissue changes were considered secondary outcomes. The following inclusion criteria were applied: Randomised controlled or prospective studies in English. More than five implants per group with a minimum of six months follow-up. Exclusion criteria were animal and in vitro studies, simple evaluations without comparators or analyses of loading protocols.

Two researchers independently selected and screened articles PubMed/Medline, Embase, and Cochrane databases and manually searched relevant specialist journals. Quality assessment was undertaken using the Jadad scale and Cochrane Collaboration’s tool for assessing risk of bias.


  • The systematic Search found 30 papers out of 3049 which fulfilled the inclusion criteria. On the Jadad risk of bias assessment only 8/30 studies were evaluated as high quality.
  • Meta-analysis results (Primary outcomes)
Relative risk(95% Confidence Interval) Probability
Survival favours healed sockets 2.49, (1.44 – 4.29) p = 0.001
Type 1 compared with type 2 1.45, (0.53 – 3.98). p = 0.47
Type 1 compared with type 3 5.25, (1.67 – 16.49) p = 0.005
Type 1 compared with type 4 2.86, (1.22 – 6.70) p = 0.02
  • There were no statistical differences in the secondary outcomes.


The authors concluded:-

In conclusion, immediate implant insertion should be performed with caution because implant survival rates are significantly lower than with implants inserted into healed sockets.


My intuition tells me that the authors may have the right answer but the evidence they present does not support this for various methodological reasons. The major problem is that the survival data is of relatively short duration and heterogeneous with a mean follow-up being 24 months, median 18 months and a mode  of 12 months.

Clinicians mostly will only be interested in long-term data (60 months plus). Focusing on just these longer-term studies papers in the review just leaves three papers (Cooper et al 2014, Polizzi et al 2000 and Raes et al 2016) , so a second Raes paper (Raes et al 2013)  with a stated 52 months follow up and the 2015 Oxby paper with 55 months follow up were reviewed and meta-analysed.

Looking at these research papers with the longest follow-up is simpler to appraise than the 30 the authors included. Full texts were obtained and the following conclusions made:

  • The Raes paper (Raes et al 2013) states only 52 weeks follow-up not 52 months as in the review, which is quite important if we are meant to be looking a survival studies.
  • In the Polizzi paper (Polizzi et al 2000) there is no randomisation between the healed and fresh extraction sockets.
  • The Oxby paper reads as though it is retrospective review and 25% of the sample was excluded after implant placement as the loading protocol exceeded 60 days (this group could possibly contain the failures?). Not all the implants were reviewed at 60 months (38/182 were reviewed between 36-48 months, 114/182 between 49-60 months and 30/182 between 60-63 months).
  • Lost to follow (LTF) up in the studies varies from 13% – 40%. The authors classified the LFT patients as missing completely at random to optimise the survival data.

The 2013 Raes paper was therefore excluded as the follow-up was too short, and the Oxby paper as a retrospective study (exclusion criteria). The remaining studies were included in a meta-analysis. Group a. is the data as published in the systematic review and Group b. where LTF is considered in the calculations as a failure.

Fig.1 shows the new risk ratio (RR) for the long-term data has reduced from 2.49 to 1.28. If missing data is considered as a failure the RR drops to 1.06 (Fig. 2). An interesting observation is that the risk difference for Group a (Fig. 3) is 0.01.

Fig. 1. Forest plot for the event ‘60-month implants survival rates’ for Group a.


Fig. 2. Forest plot for the event ‘60-month implants survival rates’ for Group b.


Fig. 3. Forest plot for the Risk Difference ‘60 month implants survival rates’ for Group a.


In conclusion from this data there is no difference between techniques, possibly due to the ability to select cases rather than a true randomisation. One interesting point is that long-term survival for fresh v. healed was 94.4 and 96.9; if missing data is considered a failure 5-year survival drops by a further 15%. As usual the truth lies somewhere in between.


Primary paper

Mello CC, Lemos CAA, Verri FR, Dos Santos DM, Goiato MC, Pellizzer EP.Immediate implant placement into fresh extraction sockets versus delayed implants into healed sockets: A systematic review and meta-analysis. Int J Oral Maxillofac Surg. 2017 May 3. pii: S0901-5027(17)31361-9. doi: 10.1016/j.ijom.2017.03.016. [Epub ahead of print] Review. PubMed PMID: 28478869.

Other references

Cooper LF, Reside GJ, Raes F, Garriga JS, Tarrida LG, Wiltfang J, Kern M, De Bruyn H. Immediate provisionalization of dental implants placed in healed alveolar ridges and extraction sockets: a 5-year prospective evaluation. Int J Oral Maxillofac Implants. 2014 May-Jun;29(3):709-17.

Polizzi G, Grunder U, Goené R, Hatano N, Henry P, Jackson WJ, Kawamura K, Renouard F, Rosenberg R, Triplett G, Werbitt M, Lithner B. Immediate and delayed implant placement into extraction sockets: a 5-year report. Clin Implant Dent Relat Res. 2000;2(2):93-9.

Raes S, Raes F, Cooper L, Giner Tarrida L, Vervaeke S, Cosyn J, De Bruyn H. Oral health-related quality of life changes after placement of immediately loaded single implants in healed alveolar ridges or extraction sockets: a 5-year prospective follow-up study. Clin Oral Implants Res. 2017 Jun;28(6):662-667. Epub 2016 May 22.

Oxby G, Oxby F, Oxby J, Saltvik T, Nilsson P. Early Loading of Fluoridated Implants Placed in Fresh Extraction Sockets and Healed Bone: A 3- to 5-Year Clinical and Radiographic Follow-Up Study of 39 Consecutive Patients. Clin Implant Dent Relat Res. 2015 Oct;17(5):898-907.

Raes F, Cosyn J, De Bruyn H. Clinical, aesthetic, and patient-related outcome of immediately loaded single implants in the anterior maxilla: a prospective study in extraction sockets, healed ridges, and grafted sites. Clin Implant Dent Relat Res. 2013 Dec;15(6):819-35.

Dental Elf – 2 August 2017

Dental Elf -12th Dec 2014


The 10 Golden Rules

I was just fli164145237_1595faa60d_bcking through some files and found a nice little check list from a course run by the University of Bern in the about 2004. It’s a fantastic reminder of the fundamentals of dental treatment planning.


  1. Treat oral disease as an opportunistic infection.
  2. Eliminate and control infection.
  3. Obtain and maintain health before aesthetics.
  4. Classify chewing elements according to prognosis.
  5. Follow a sequence of treatment phases.
  6. Satisfy the patients needs for aesthetics and function.
  7. Consider shortened dental arches (Kayser).
  8. Increase chewing comfort in the premolar region.
  9. Diagnose continually during maintenance.
  10. Render interceptive supportive care.

Methodological Quality of Consensus Guidelines in Implant Dentistry (Faggion et al. 2017)

Clinicians rely heavily on consensus guidelines when they develop treatment protocols for their patients. The idea is that the most experienced clinicians and academics meet and systematically develop what they feel is best practice in their particular field. Health care providers and regulators then rely on this distillation of knowledge, experience and evidence in their decision making. A systematic review of guideline quality in peer-reviewed medical literature was conducted in 1999  and found only a 43% adherence to reporting standards (Shaneyfelt et al. 1999). In 2003, a generic tool was created by the AGREE (Appraisal of Guidelines, REsearch and Evaluation) collaboration to create “common standards to improve the quality process and reporting of guideline development” (Cluzeau et al. 2003). With use the protocol evolved into AGREE II (Brouwers et al. 2010) which is made up of 23 items in 6 domains:

  1. Scope and Purpose
  2. Stakeholder Involvement
  3. Rigour of Development
  4. Clarity of Presentation
  5. Applicability
  6. Editorial Independence

The research question reference consensus guidelines in implant dentistry was: “Do consensus guidelines published in high ranked implant journals meet the requirements proposed in the AGREE II instrument? A secondary objective was to evaluate whether the inclusion of systematic reviews conducted to support the consensus guidelines improved their methodological quality.


Two authors (KA,MA) independently searched and evaluated consensus guidelines from the 6 highest impact implant dentistry journals (assigned by Journal Citation Reports) and Medline database via PubMed. The search was limited to May 2009 – February 2016 in line with the publication of AGREE II. Reasons for papers to be excluded was recorded.

Four authors (KA,TA,LM,MA), following assessor training then independently applied the AGREE II tools to the consensus guidelines as described in the user’s manual. Domain scores were presented as median percentages of the maximum possible with their respective interquartile ranges. Domain scores were divided into consensus guidelines, and consensus guidelines with systematic reviews.


  • From an initial 258 publications 27 consensus guidelines fulfilled the inclusion criteria of which 19 was included for comparison
  • The journals were: Clinical Oral Implants Research (COIR), Clinical Implant Dentistry and Related Research (CIDRR), European Journal of Oral Implants (EJOI), The International Journal of Oral and Maxillofacial Implants (JOMI), Journal of Oral Implantology, and Implant Dentistry.
  • 26 guidelines were developed after meetings in Europe.
  • The European Association of Osseointigration (EAO) developed the most guidelines (n=9)
  • The number of authors ranged from 2-27 (median, 9)

Primary Outcomes

AGREE II Domains Consensus guidelines only.

Median is % of maximum score

Consensus guidelines plus systematic reviews.


Domain 4 (Clarity of presentation) Median, 75; (IQR 15.30) Median, 84.70;(IQR, 9.80).
Domain 1 (Scope and Purpose) Median, 69.40; (IQR, 36.20). Median, 79.20; (IQR, 73)
Domain 2 (Stakeholder Involvement) Median, 41.70; (IQR, 17.70) Median, 76.40; (IQR,18.10)
Domain 6 (Editorial Independence) Median, 41.7 ;(IQR, 83.30) Median, 56.30 (IQR, 34.40)
Domain 3 (Rigour of Development) Median, 30.70; (IQR, 26.50) Median, 50 (IQR,44.40)
Domain 5 (Applicability) Median, 26;(IQR, 12.50) Median, 26; (IQR, 20.80)

Conclusion (the author concluded)

“Methodological improvement of consensus guidelines published in major implant dentistry journals is needed. The findings of the present study may help researchers to better develop consensus guidelines in implant dentistry, which will improve the quality and trust of information needed to make proper clinical decisions”.


For the clinician in practice placing or restoring on dental implants this is a very important paper and goes a long way in explaining the disjoint between what is presented on the international conference circuit and what we see in day-day practice.

To help with interpreting the authors data I have modified it slightly to present the data as median with 95% confidence intervals and place the meta-analysis it in a forest plot.

The first chart show the AGREE II scores relating to the consensus guidelines that did not include the use of systematic reviews. The highest scoring domains were Domain 4. (Clarity of Presentation) and Domain 1. (Scope and Purpose) which score in the 70’s. There is a gap and the next four Domains in rank order are; 6. (Editorial Independence), 2. (Stakeholder Involvement), 3. (Rigour of Development) and lastly 6. (Applicability). These narrative guidelines therefore only fulfil 50% of the AGREE II criteria.

Agree II narr

The second chart show a meta-analysis comparing the narrative guideline scores compared with the consensus guidelines + systematic reviews, and there is roughly a 9% improvement bringing the score up to 60% compliance with AGREE II.

Forest plot

What becomes obvious however is that 18% improvement came out of Domain 3. (Rigour of Development) but 34% from Domain 6. (Editorial Independence). Going back then to the meta-analysis of consensus guidelines + systematic reviews the improvement has been weak and polarises the results.

Agree II SR

From a clinicians point of view what options do we have available to us to improve consensus guidelines?


  • Domains 1 (Scope and Purpose) and 4 (Clarity of Presentation) are good, we know what questions to ask and how to present them.
  • Domain 6 (Editorial Independence) is improving but there still needs to be more clarity over the editorial independence from funding bodies and conflicts of interest from the funding bodies and authors.
  • Domain 3. (Rigour of Development) More effort needs to be spent in this area as is is the foundation on which the guidelines are built, based on validated systematic methods for assessing and analysing the relevant primary research. Analysis also needs to include health benefits, side effects and complications. The guidelines should also be externally validated prior to publication.
  • Domain 2 (Stakeholder Involvement) at present is dominated by University professors and private practitioners with strong academic connections. This area would benefit from the views of clinicians working outside of specialist practice, health care providers, funders and patient groups.
  • Domain 6. (Applicability) is the weakest domain, this may be in part due to the lack of input at the stakeholder level . For clinicians in practice, and their patients cost implications are a major barrier to applying guideline recommendations.


 Primary paper

Faggion, C.M.J. et al., 2017. Methodological Quality of Consensus Guidelines in Implant Dentistry. PloS one, 12(1), p.e0170262. Available at:

 Other references

Brouwers, M.C. et al., 2010. AGREE II: Advancing guideline development, reporting and evaluation in health care. Journal of Clinical Epidemiology, 63(12), pp.1308–1311.

Cluzeau, F. et al., 2003. Development and validation of an international appraisal instrument for assessing the quality of clinical practice guidelines: the AGREE project. Quality & safety in health care, 12(1), pp.18–23. Available at:

Shaneyfelt, T.M., Mayo-Smith, M.F. & Rothwangl, J., 1999. Are guidelines following guidelines? JAMA: The Journal of the American Medical Association, 281(20), pp.1900–1905.