9. 2 Various implant characteristics/systems Is a surface modification, an implant shape, a material or an implant system more effective than the others? Last literature search: February 2005. 12 RCTs with 512 participants and 12 different implant systems (19 RCTs excluded). 4 RCTs with a 5-year follow-up. Minor statistically significant differences in marginal bone loss and in the occurrence of perimplantitis (20% risk reduction to have perimplantitis at 3 years around implants with a machined surface). No statistically significant difference in failure rates. We do not know whether any implant system is superior to the others. It does not mean that they are all the same!
10. 3 Immediate, early or conventional loading Is there any difference if implants are immediately or early loaded? Last literature search: February 2004. 5 RCTs with 124 participants (2 RCTs excluded). For “good quality mandibles” we do not know whether a difference does exist. It does not mean that the techniques provide the same results!
11. 4 Maintenance Which is the most effective maintenance technique or regimen? Last literature search: June 2004. 5 RCTs with 127 participants (9 RCTs were excluded); electric (1 RCT) and sonic (1 RCT) vs manual toothbrush; phosphoric acid gel vs debridement (1 RCT); subgingival vs chlorhexidine mouthrinses (1 RCT); adjunctive Listerine mouthrinse vs placebo (1 RCT). Follow-up: 6 weeks-5 months. Adjunctive Listerine mouthrinse reduces dental plaque and marginal bleeding.
12. 5 Surgical techniques Is there any surgical technique associated to higher success rates? Last literature search: September 2002. 4 RCTs (5 RCTs excluded). 2 RCTs compared 2 versus 4 implants with mandibular overdentures (170 participants); 2 RCTs compared a crestal surgical incision with a vestibular incision (20 participants). We do not know whether a surgical technique is superior, however, 2 mandibular implants can be sufficient to hold an overdenture. It does not mean that all techniques are the same!
13. 6 Immediate, immediate-delayed and delayed implants in extraction sockets How long time we need to wait to insert an implant in postextractive sockets? Last literature search: March 2006. 1 RCT with 46 participants: immediate delayed (ca 10 days) vs delayed (ca 3 months) implants. Follow-up (loading) 1 year and half. Patients treated with immediate-delayed implants were more satisfied, and the perimplant tissues position was judged to be more appropriate in relation to the neighbouring teeth by and independent and masked assessor.
16. 7 Treatment of perimplantitis No difference between more complex procedures and conventional debridement in light forms of perimplantitis. The adjunctive use of local antibiotics (doxycycline) to debridement showed an improvement of about 0.6 mm for PAL and PPD, after 4 months in patients affected by severe forms of perimplantitis (bone loss > 50%).
17. 8 Preprosthetic surgery vs implants Which intervention is more effective: preprosthetic surgery and dentures vs a implant supported denture? Last literature search: October 2005. 1 RCT with 60 participants. Patients treated with preprosthetic surgery and dentures are less satisfied than patients who received a mandibular overdenture on implants.
18. 9 Use of prophylactic antibiotics Does the use of prophylactic antibiotics at implant placement decreases postoperative complications and early failures? Last literature search: March 2006. 0 RCT.
19. 10 Zygomatic implants Zygomatic implants with and without bone grafting versus conventional implants in augmented bone. Last literature search: March 2006. 0 RCT.
20. 11 Hyperbaric oxygen therapy Does hyperbaric oxygen (HBO) therapy decrease implant failures and complications in irradiated patients? Last literature search: March 2006. 0 RCT.
21. 12 Denture chewing surface designs Which denture chewing surface design should be used? Last literature search: April 2004. 1 cross-over RCT with 30 participants (1 RCT excluded): lingualised (maxillary anatomic and mandibular non-anatomic) vs zero-degree teeth. Patients preferred dentures with lingualised teeth.