Abstract
PURPOSE:
To
compare outcomes of immediate non-occlusal loading with delayed implant
loading in the bilateral replacement of mandibular first molars.
MATERIALS AND METHODS:
This
study was designed as a split-mouth, randomised controlled trial.
Twenty patients with bilaterally missing mandibular first molars
randomly received immediately or conventionally loaded single implants.
One molar was restored with a non-occlusal temporary crown within 24
hours after implant placement (immediate loading group, IL) while the
contralateral molar was restored with a definitive crown 4 to 5 months
later (delayed loading group, DL). A total of 40 implants were
installed. All implants were inserted in healed bone with an insertion
torque between 35 and 45 Ncm. Outcome measures were implant failure,
complications, radiographic marginal bone level changes, probing pocket
depths (PPDs) and bleeding on probing (BOP). Clinical data were
collected at implant placement, and after 6, 12 and 60 months.
RESULTS:
No
patients dropped out and no implant failed. Only minor prosthetic
complications were observed (two provisional acrylic crown fractures in
the IL group and four ceramic chipping in the DL group). Two patients
had bilateral peri-implant mucosal inflammation with BOP after 6 months.
The differences between groups were not statistically significant (OR =
0.500; 95% CI: 0.045 to 3.489; P = 0.6831). At the 1-year follow-up
examination, the mean marginal bone level was 0.83 ± 0.16 mm (95% CI:
0.75 to 0.91) in the IL group and 0.86 ± 0.16 mm (95% CI: 0.78 to 0.94)
in the DL group, with no statistically significant differences between
groups (difference = 0.03 ± 0.15 mm; 95% CI: -0.07 to 0.07; P = 0.53).
After 5 years, mean marginal bone level was 1.06 ± 0.38 mm (95% CI: 0.97
to 1.15) in the IL group and 1.07 ± 0.32 mm (95% CI: 0.95 to 1.16) in
the DL group, with no statistically significant differences between
groups (difference = 0.01 ± 0.22 mm; 95% CI: -0.10 to 0.10; P = 0.96).
The mean marginal bone loss after 5 years was 0.62 ± 0.45 mm in the IL
group and 0.69 ± 0.33 mm in the DL group (difference = 0.07 ± 0.32 mm;
95% CI: -0.10 to 0.18; P = 0.567). At the 5-year follow-up the mean PPD
and BOP values were 2.82 ± 0.65 mm and 1.17 ± 0.92 in the IL group, and
2.85 ± 0.53 mm and 1.17 ± 0.86 in the DL group, respectively. No
significant differences were found (difference = 0.03 ± 0.15 mm; 95% CI:
-0.15 to 0.21; P = 0.990; and 0.01 ± 0.07; 95% CI: -0.06 to 0.08; P =
1.000, respectively).
CONCLUSIONS:
Within the limitations
of this study, the present data seem to confirm the hypothesis that the
clinical outcome of immediate versus delayed loading of implants in
mandibular fist molar sites is comparable.
Comments