Here’s the link to my latest summary review paper in EBD
Here’s the link to my latest summary review paper in EBD
Immediate 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:
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.
|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|
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 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.
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.
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 main aim of this systematic review is to look at implant based restorative options for restoring the atrophic posterior mandible using osseointegrated dental implants. The atrophic posterior mandible is defined here as having a residual ridge height of 8mm from the inferior dental nerve to the crest of the ridge. The two options considered are short dental implants < 8mm in length placed in pristine bone compared to standard long implants >8 mm placed after bone augmentation procedures, in this care either autogenous onlay grafts or non-onlay autogenous and xenogeneic bone grafts
This review followed the PRISMA statement. Searches were screened by two independent researchers using Medline, and Cochrane Oral Health Group databases. Databases were searched from January 1st 2006 to July 30th 2016 and restricted to English, manual searches were also carried out in the relevant major journals.
Inclusion criteria were: Randomised clinical studies (RCT’s) that included clinical or radiological outcomes of the surgical strategies for rehabilitation of atrophic posterior mandibles in partially edentulous patients. This including any dimensional change, survival rate and adverse event and follow-up from 12 to 24 months. Excluded studies included animal studies, repeated reports of the same study, and studies including patients who were heavy smokers, drinkers, or had poor oral hygiene.
Quality appraisal was carried out by each of the authors using the Cochrane Collaboration tool for assessing risk of bias in randomised trials. The primary outcomes were implant failure and marginal bone loss. Secondary outcomes were biological complications and prosthesis failure.
|Group A||Risk Ratio||95% Confidence Interval||P-Value|
|Short implant v. long implant (Implant failure)||1.59||0.54 to 4.69||0.397|
|Short implant v. long implant (Prosthesis failure)||1.49||0.0.56 to 3.96||0.426|
|Short implant v. long implant (biological complications)||2.82||1.81 to 4.4||<0.0001|
|Mean Diff||95%Confidence Interval||P-Value|
|Short implant v. long implant (marginal bone loss)||0.05 mm||0.026 to 0.079||<0.0001|
|Group B||Risk Ratio||95% Confidence Interval||P-Value|
|Onlay Group v. Non-onlay Group||1.81||0.42 to 7.84||0.43|
|Mean Diff||95% Confidence Interval||P-Value|
|Onlay Group v. Non-onlay Group||0.006 mm||-0.19 to 0.177||0.946|
The authors concluded:-
Findings from subgroup analyses revealed that
(1) short implants placed in the posterior atrophic areas of partially edentulous mandibles were associated with superior outcomes compared with long implants in augmented bone, such as lower rate of biological complications and of peri-implantbone loss; whereas
(2), there was no evidence that onlay augmentation was inferior to any of theother augmentation techniques employed
Even though the results of this systematic review and meta-analysis favour short implants over standard implants placed in augmented bone the evidence must be interpreted with extreme caution for the following reasons:
In general, there are issues with statistical v. clinical significance. Even though the risk ratio favours short implants in terms of reduced biological complications there are no other metrics where there is a visible clinical difference; an example would be marginal bone loss of 0.05mm. Some qualitative research would be interesting to explore the patient’s experience of bone augmentation procedures in terms of morbidity against short implant placement into pristine bone.
Toti, P. et al., 2017. Surgical techniques used in the rehabilitation of partially edentulous patients with atrophic posterior mandibles: A systematic review and meta-analysis of randomized controlled clinical trials. Journal of Cranio-Maxillofacial Surgery.
Dental Elf – 2nd Dec 2015