Evaluating the quality of active-control trials in periodontal research

Prehydrated collagenated cortico-cancellous heterologous bone gel and papillae tunneling for isolated intrabony defects: 12-month noninferiority trial

OBJECTIVES

This study assessed the effectiveness of prehydrated collagenated xenogenic bone gel and a collagenated cortico-cancellous heterologous bone mixture in conjunction with papillae tunneling techniques (PTT) for treating isolated periodontal intraosseous defects.

MATERIALS AND METHODS

Twenty patients with periodontitis stage III/IV and at least one deep isolated interdental 2/3-wall intraosseous defect were included in the study. Surgical incisions were made vertically at the adjacent tooth or horizontally at the mucogingival junction. A full-thickness flap was then carefully lifted under the papillae using special tunneling instruments. The root surfaces were completely cleaned, and the defects were randomly filled with either prehydrated collagenated bone gel (test group; n = 10) or collagenated cortico-cancellous heterologous bone mixture (control group; n = 10). Wounds were closed with microsurgical sutures. We predicted that the lower 95% confidence interval for the difference between the two procedures would exceed a prespecified noninferiority threshold.

RESULTS

All wounds closed sufficiently to prevent biomaterial exposure. The test and control groups showed similar mean pocket depth reduction (3.5 ± 1.0 vs. 3.9 ± 1.7 mm; p = 0.52), similar gingival recession (-0.10 ± 0.99 vs. 0.2 ± 0.8 mm; p = 0.46), and similar clinical attachment gain (3.6 ± 1.51 vs. 3.7 ± 1.8 mm; p = 0.89) at the 12-month follow-up. All results were below the noninferiority margin of the sample.

CONCLUSIONS

At 12 months, prehydrated collagenous bone gel performed similarly to collagenous heterologous bone granules in the treatment of intraosseous lesions with PTT. In addition, both biomaterials preserved soft tissue with minimal further recession at 1 year.

CLINICAL RELEVANCE

When combined with PTT, collagenous xenogeneic bone granules and prehydrated collagenous bone gel achieve comparable clinical outcomes in intrabony defects. The study was registered under the NCT04782921 on ClinicalTrails.

Reliability and validity of MINCIR scale for methodological quality in dental therapy research

The clinical paradigm of evidence-based medicine requires a foundation of good quality research upon which clinical and epidemiological decisions can be based. Several instruments have been designed to assess research quality and validated, though most have limitations. The MINCIR scale was designed to determine the methodological quality (MQ) of clinical research, its psychometric properties for dental research involving large-scale evaluations have not yet been determined. The aim of this study was to determine the validity and reliability of the MINCIR scale for assessment of the MQ of dental therapy studies published in journals indexed in Institute for Scientific Information (ISI) databases. A validation study was performed on a sample of 99 articles from four representative ISI dental journals. Criterion validity was determined in relation to level of evidence (LoE) classification as described by the Oxford Center for Evidence-Based Medicine (OCEBM) ranking system, reliability was determined by calculation of intra-class correlation coefficient (ICC) values, and internal consistency was determined by calculation of Cronbach's alpha. Very good inter-observer reliability (ICC=0.93), excellent temporal stability (ICC=0.97), good internal consistency (Cronbach's alpha=0.77), and a strong (inverse) correlation with OCEBM LoEs (-0.807; p<.0001) were obtained. These results indicate that the MINCIR scale has adequate psychometric properties and therefore is a valid option for use in the assessment of MQ in dental therapy research articles.

Risk of bias of animal studies on regenerative procedures for periodontal and peri-implant bone defects - a systematic review

OBJECTIVES

(1) To assess the risk of bias of studies in which animal models were used for investigating regenerative therapies for periodontal and peri-implant defects. (2) To investigate changes in risk of bias by comparing samples drawn from two different publication periods.

MATERIAL & METHODS

We searched the PubMed and LILACS electronic databases, independently and in duplicate, for randomized and controlled trials published from 1998 to 2000 and from 2008 to 2010. Hand searching included search of 10 dental journals, in the issues published between August 2008 and August 2010. Studies on non-human primates and canines were included. We assessed independently and in triplicate the risk of bias with reference to a six-item checklist based on the Cochrane Collaboration's tool for assessing the risk of bias and information about formal sample size calculation.

RESULTS

One hundred and seven studies were included in the review. Checklist items were poorly reported in the studies selected, and therefore for most of the studies, the risk of bias was unclear.

CONCLUSION

As a result of the unclear risk of bias of animal studies in periodontal and peri-implant treatments, it is difficult to determine the accuracy of treatment effect estimates. There is a need for standardization of reporting procedures on animal experiments.

Comparison of the effects of treatment of peri-implant infection in animal and human studies: systematic review and meta-analysis

OBJECTIVE

The main objective of this systematic review is to compare the effects of treatment of peri-implant infection between animal and human studies.

MATERIAL AND METHODS

A literature search was conducted using the Medline, Cochrane Central Register of Controlled Trials, and Latin American and Caribbean Health Sciences Literature databases up to and including May 2008. In addition, bibliographies of systematic reviews on peri-implant diseases were searched manually. Non-surgical and surgical treatments of peri-implantitis/mucositis in animal models or human studies were compared. Meta-analysis was conducted to investigate the difference between the reported treatment effects in animal and human studies. Changes in probing pocket depth (PPD) and probing attachment level (PAL) from baseline measurements were used as measures of outcome. Single-level and multilevel meta-regression analysis was performed by taking into account the different follow-up times of the studies included.

RESULTS

The single-level and multilevel random-effects meta-analysis showed that the difference in PPD reduction [0.31 mm, 95% confidence interval (CI): -0.27, 0.88] and in PAL gain (0.21 mm, 95% CI: -0.47, 0.88) between animal and human studies was not statistically significant. The random-effects meta-regression suggested that studies with longer follow-up times revealed greater PPD reduction (0.25 mm per month, 95% CI: 0.14, 0.35). However, when the different follow-up times were taken into account, these differences became greater. Substantial heterogeneity between studies was found in the meta-analyses (I(2)=97.6% for animal studies and 99.9% for human studies).

CONCLUSION

There was great heterogeneity between human and animal studies in terms of study designs and treatment procedures. Therefore, the results from this meta-analysis should be interpreted with caution. Heterogeneity between studies and its causes merit further investigations.

A randomized clinical multicentre trial comparing enamel matrix derivative and membrane treatment of buccal class II furcation involvement in mandibular molars. Part III: patient factors and treatment outcome

OBJECTIVE

Evaluation of effects of patient factors on the outcome of regenerative treatment of buccal mandibular class II furcation defects.

MATERIAL AND METHODS

Fifty-one patients were recruited. In the intention-to-treat population 21 patients were allocated into the sequence left treatment with enamel matrix protein derivative (EMD) and right guided tissue regeneration (GTR) and 27 in the sequence left GTR and right EMD. Evaluated patient factors were: smoking, age, gender, hypertension and oral hygiene status. Outcome parameters included change of: (a) horizontal depth of the defect at the deepest point (b) distance from the fornix of the furcation to bone crest of the defect, (c) distance from stent to the bottom of the defect, (d) pocket depth and (e) attachment level at the middle of the furcation.

RESULTS

In patients 54 years of age and older, in males, in non-smokers and in patients with "poor" hygiene EMD-treated sites showed a significant higher mean reduction of the parameters d (age), b (gender, hygiene) a (smoking, hygiene) when compared with sites treated with GTR.

CONCLUSIONS

These data provided an indication of a possible effect of patient factors on the outcome of regenerative treatment of buccal mandibular class II furcation defects.