You will be shown the abstract of a medical clinical trial report. Your task is to extract all the findings from this report into a JSON array. Each finding should contain the following five elements:

- Intervention: The medical intervention being tested. This should be a text span copied from the input passage.
- Comparator: The baseline against which the intervention is being evaluated. This should be a text span copied from the input passage. If no comparator is reported, set to `null`.
- Outcome: The medical outcome whose effect is being measured. This should be a text span copied from the input passage.
- Effect: The effect of the intervention on the outcome, relative to the comparator. The effect should be one of the following three values: ("significantly increased", "significantly decreased", "no significant difference").
- Evidence: The evidence for the effect. This should be a text span copied from the input passage.

Please format your output as a JSON array. Each entry in the output should be an array containing the 5 elements listed above, in the following order: [<intervention>, <comparator>, <outcome>, <effect>, <evidence>].

For example, an output with two findings might read:
```
[["aspirin", "placebo", "headache severity", "significantly decreased", "Mean headache severity was significantly decreased in the aspirin group compared to the placebo group (p < 0.05)."], ["aspirin", "placebo", "weight loss", "no significant difference", "We did not observe any difference in weight loss between the group given aspirin relative to the control group"]]
```

There are 4 finding(s) in the abstract below. Please extract them. Output only the JSON array with these 4 findings. Do not include any additional text.

Abstract:
ABSTRACT.OBJECTIVES:: This study aimed to assess and compare the microleakage of two bulk fill and one conventional composite in class II restorations of primary posterior teeth.

ABSTRACT.MATERIALS AND METHODS:: This in vitro, experimental study was conducted on 60 primary mandibular second molars, which were randomly divided into three groups. Standard class II cavities were prepared in teeth and restored with 3M bulk fill composite in group 1, SonicFill bulk fill composite in group 2 and Z250 conventional composite in group 3. Single Bond 2 bonding agent was used in all cavities. The teeth were then thermocycled and immersed in 1M silver nitrate solution. The teeth were then mesiodistally sectioned and evaluated under a stereomicroscope at×10 magnification. Dye penetration depth was recorded in microns and data were analyzed using one-way ANOVA.

ABSTRACT.RESULTS:: The mean (± standard deviation) dye penetration depth in the gingival margins was 543±523μm, 343±290μm and 597±590μm for 3M bulk fill, SonicFill and Z250 conventional composite, respectively. These values were 214±93μm, 302±127μm and 199±145μm in the occlusal margins, respectively. The three groups were not significantly different in terms of occlusal or gingival microleakage (P>0.05), but gingival margins showed significantly higher microleakage than occlusal margins in all three groups (P<0.05).

ABSTRACT.CONCLUSIONS:: Bulk fill composites are not significantly different from conventional composites in terms of microleakage.

Findings:
[["SonicFill bulk fill", "Z250 conventional composite", "Microleakage of Two Bulk Fill and One Conventional Composite in Class II Restorations of Primary Posterior Teeth", "no significant difference", "The three groups were not significantly different in terms of occlusal or gingival microleakage (P\u003e0.05), but gingival margins showed significantly higher microleakage than occlusal margins in all three groups (P\u003c0.05)."], ["3M bulk fill", "SonicFill", "Microleakage of Two Bulk Fill and One Conventional Composite in Class II Restorations of Primary Posterior Teeth", "no significant difference", "The three groups were not significantly different in terms of occlusal or gingival microleakage (P\u003e0.05), but gingival margins showed significantly higher microleakage than occlusal margins in all three groups (P\u003c0.05)."], ["gingival margin of all groups", "occlusal margin of all groups", "Microleakage (dye penetration depth)", "significantly increased", "The three groups were not significantly different in terms of occlusal or gingival microleakage (P\u003e0.05), but gingival margins showed significantly higher microleakage than occlusal margins in all three groups (P\u003c0.05)."], ["3M bulk fill", "Z250 conventional composite", "Microleakage of Two Bulk Fill and One Conventional Composite in Class II Restorations of Primary Posterior Teeth", "no significant difference", "The three groups were not significantly different in terms of occlusal or gingival microleakage (P\u003e0.05), but gingival margins showed significantly higher microleakage than occlusal margins in all three groups (P\u003c0.05)."]]