Merli 2008.

Methods	Trial Design: randomised, parallel group trial Location: Rimini, Italy Number of centres: one (private practice) Recruitment period: not stated Funding source: partial support for this study was provided by Thommen Medical AG, Wldenburg, Switzerland
Participants	Inclusion criteria: partially edentulous patients (both mandibles and maxillae) allowing the placement of at least 9.5 mm long implants and the bone thickness at implant sites had to be of at least 5.5 mm. For implants to be immediately loaded, a primary implant stability of 40 Ncm had to be achieved at implant insertion Exclusion criteria: patients irradiated in the head and neck area within the previous year, severe bruxism, substance abusers, pregnancy, uncontrolled diabetes, and any systemic diseases likely to compromise implant surgery, lack of opposing occluding dentition, a need for bone‐augmentation procedures with exception of Bio‐Oss granules in post‐extractive sites, presence of less than 4 mm of keratinised mucosa Age at baseline: immediate 50.3 (28 to 72 years); early 48.7 (19 to 68 years) Gender: immediate M10/F20; early M12/F18 Number randomised: 60 Number evaluated: 60
Interventions	Comparison: Immediate versus early loading Gp A (n = 30 patients, 35 implants) Immediate loading: 1 or more implants placed with a flapless technique and restored with non‐occluding acrylic restorations, within 72 hours Gp B (n = 30 patients, 34 implants) Early loading: 1 or more implants placed with a flapless technique and restored with non‐occluding acrylic restorations after 6 weeks For all patients permanent restoration with occluding cemented metal‐ceramic crowns was performed after 6 months SPI®Element System (Thommen Medical AG, Waldenburg, Switzerland) sand‐blasted acid‐etched screws, and in some of the post‐extraction sites SPI®Contact troncoconical screws were used Duration of follow‐up: 1 year
Outcomes	Prosthesis/implant failures and complications 1‐year data used
Notes	Sample size calculation: reported that 26 patients per group would be required to show a difference in proportion of failures from 39% to 4%
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Reported in the first article: "A manually generated restricted randomization list was used to create two groups with equal numbers of patients. Only one of the investigators, not involved in the selection and treatment of the patients, was aware of the randomization sequence and had access to the randomization list stored in a password‐protected portable computer"
Allocation concealment (selection bias)	Low risk	Reported in the first article: "The randomized codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes were opened sequentially only after the implants to be included in the trial were inserted, therefore treatment allocation was concealed to the investigator in charge of enrolling and treating the patients included in the trial"
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Reported in the first article: "These outcome measures (prosthetic failures, implant failures and complications) were assessed by an independent assessor (FB), who was not blinded to the interventions" Reported in the third article: "Although patients and the surgeon were aware of the allocated arm, radiographic outcome assessor (G. Mariotti) was kept blinded to the allocation. Prosthesis failure, implant failure and complications were assessed by an independent assessor (M. Moscatelli), who was not blinded to the intervention"
Incomplete outcome data (attrition bias) All outcomes	Low risk	All data presented
Selective reporting (reporting bias)	Low risk	All outcomes were presented
Other bias	High risk	A substantial rate of protocol deviations were present, for instance of the 30 patients allocated to the early loading group, 5 were conventionally loaded and 2 immediately loaded