Three-dimensional quantitative measurement of buccal augmented tissue with modified coronally advanced tunnel technique and de-epithelialized gingival graft: a prospective case series

Digitally measured exposed root surface area for predicting the effectiveness of modified coronally advanced tunnel combined de-epithelialized gingival grafting in the treatment of multiple adjacent gingival recessions

OBJECTIVES

To assess the predictive value of baseline digitally measured exposure root surface area (ERSA) on the effectiveness of modified coronally advanced tunnel and de-epithelialized gingival grafting (MCAT + DGG) technique for the treatment of multiple adjacent gingival recessions (MAGRs).

MATERIALS AND METHODS

A total of 96 gingival recessions (48 RT1 and 48 RT2) from 30 subjects were included. ERSA was measured on the digital model obtained by intraoral scanner. Generalized linear model was used to analyze the possible correlation of ERSA, Cairo recession type (RT), gingival biotype, keratinized gingival width (KTW), tooth type, and cervical step-like morphology on the mean root coverage (MRC) and complete root coverage (CRC) at 1-year after MCAT + DGG. The predictive accuracy of CRC is tested using receiver-operator characteristic curves.

RESULTS

At 1-year postoperatively, the MRC for RT1 was 95.14 ± 10.25%, which was significantly higher than 78.42 ± 22.57% for RT2 (p < 0.001). ERSA (OR:1.342, p < 0.001), KTW (OR:1.902, p = 0.028) and lower incisors (OR:15.716, p = 0.008) were independent risk factors for predicting MRC. ERSA and MRC showed significant negative correlation in RT2(r = -0.558, p < 0.001), but not in RT1(r = 0.220, p = 0.882). Meanwhile, ERSA (OR:1.232, p = 0.005) and Cairo RT (OR:3.740, p = 0.040) were independent risk factors for predicting CRC. For RT2, the area under curve was 0.848 and 0.898 for ERSA without or with other correction factors, respectively.

CONCLUSIONS

Digitally measured ERSA may provide strong predictive values for RT1 and RT2 defects treated with MCAT + DGG.

CLINICAL RELEVANCE

This study demonstrates that digitally measured ERSA is a valid outcome predictor for root coverage surgery, especially applicable for predicting RT2 MAGRs.

Efficacy of Tunnel Technique (TUN) versus Coronally Advanced Flap (CAF) in the Management of Multiple Gingival Recession Defects: A Meta-Analysis

Objective

We systematically assessed the efficacy of tunnel technique (TUN) vs. coronally advanced flap (CAF) in the management of multiple gingival recession defects in adults.

Methods

Five databases were searched until September 2021 for randomized controlled trials (RCTs) assessing TUN vs. CAF; grafts of interest were acellular dermal matrix (ADM) and connective tissue graft (CTG). Primary outcomes were root coverage (RC) and complete root coverage (CRC). Secondary outcomes were clinical attachment level (CAL), keratinized tissue width (KTW), probing depth (PD), and recession coverage (REC). Effect measures were risk ratio (RR) or mean difference (MD) with their confidence intervals (95% CI). Inverse variance methods and random-effects model meta-analyses were used. Subgroup analyses by the type of graft were performed. Quality of evidence was assessed using GRADE methodology.

Results

Five RCTs (n = 173) were included, with a follow-up of 6 months for all outcomes. In comparison to CAF, TUN did not significantly reduce CRC (RR 0.65; 95% CI 0.002-176.7; p = 0.51) and did not increase RC (MD 0.99%; 95% CI -6.7 to 8.6; p = 0.80). In comparison to CAF, TUN showed no significant reduction of secondary outcomes. Subgroup analyses by type of graft showed no differences in comparison to primary analyses for primary and secondary outcomes. Three RCTs had a high risk of bias, and five RCTs had very low quality of evidence for all outcomes.

Conclusions

In adults with gingival recessions, TUN had similar primary and secondary outcomes in comparison with CAF. Subgroup analyses by the type of graft did not affect main conclusions. More RCTs with better design are needed to further characterize the effects of TUN vs. CAF in the treatment of multiple gingival recession defects.

Accurate gingival recession quantification using 3D digital dental models

Objectives

To develop and validate a method for accurate quantitative assessment of gingival recessions based on superimposition of serial 3D digital models.

Materials and methods

Gingival recessions of mild (0.5–2 mm) and increased (3–7 mm) severity were simulated on stone casts and surface models were created. The outlines of the gingival margins of the mild (A) and severe recessions (B) were compared to the original gingival margins following 3D best fit superimposition through a gold standard technique (GS), which used intact adjacent structures, and the tested method (CC), which used single tooth crowns at the position of recessions, as superimposition reference. The primary outcome was the distance between the most apical point of each corresponding gingival margin along the respective tooth long axis.

Results

For mild recessions, the median difference of the test methods (CC_A) from the reference method (GS_A) was 0.008 mm (IQR: 0.093; range: − 0.143, 0.147). For severe recessions, the median difference of the test method (CC_B) from the reference method (GS_B) was 0.009 mm (IQR: 0.091; range: − 0.170, 0.198). The proposed method (CC) showed very high intra- and inter-operator reproducibility (median: 0.025 and 0.033 mm, respectively).

Conclusions

The suggested method offers highly accurate monitoring of gingival margin changes and diagnosis of gingival recessions using 3D digital dental models. The method is applicable irrespective of changes in tooth position or form, allowing for assessments over any time span.

Clinical relevance

The accurate detection and visualization of gingival margin changes in 3D will enhance diagnosis and patient-doctor communication.

Recombinant human platelet-derived growth factor improves root coverage of a collagen matrix for multiple adjacent gingival recessions: A triple-blinded, randomized, placebo-controlled trial

AIM

To evaluate the efficacy of recombinant human platelet-derived growth factor (rhPDGF)-BB combined with a cross-linked collagen matrix (CCM) for the treatment of multiple adjacent gingival recession type 1 defects (MAGRs) in combination with the coronally advanced flap (CAF).

MATERIALS AND METHODS

Thirty patients were enrolled in this triple-blind, randomized, placebo-controlled trial and treated with either CAF + CCM + rhPDGF, or CAF + CCM + saline. The primary outcome was mean root coverage (mRC) at 6 months. Complete root coverage, gain in gingival thickness (GT), keratinized tissue width, volumetric and ultrasonographic changes, and patient-reported outcome measures were also assessed. Mixed-modelling regression analyses were used for statistical comparisons.

RESULTS

At 6 months, the mRC of the CCM + rhPDGF and CCM alone groups were 88.25% and 77.72%, respectively (p = .02). A significant gain in GT was consistently observed for both treatment arms, and more so for the patients receiving the matrix containing rhPDGF through time (0.51 vs. 0.80 mm, on average, p = .01). The rhPDGF + CCM treated patients presented greater volume gain, higher soft tissue thickness, and a superior aesthetic score.

CONCLUSION

rhPDGF enhances the clinical, volumetric, and aesthetic outcomes of MAGRs above the results achieved with CAF + CCM alone (ClinicalTrials.gov NCT04462237).

Evaluation of gingival recessions with conventional versus digital methods

OBJECTIVES

The present study aimed to compare the conventional clinical and digital methods evaluating differences in gingival recession (ΔREC) in patients with advanced periodontitis treated with the non-surgical treatment protocol.

METHODS

Agreement between the methods was evaluated on a sample of ten patients with periodontitis (stage III/IV, grade B/C) with acquired clinical measurements and digital models from baseline (T0) and 12-months after non-surgical treatment of periodontitis (T1). The evaluation was performed on maxillary teeth from right to left second premolar resulting in overall 99 teeth. Clinical evaluation was performed by subtracting the distance measurements between gingival margin and cemento-enamel junction, obtained at T0 and T1 by a calibrated examiner (intra-examiner agreement >90%). The digital evaluation was performed directly by measuring the distance between the gingival margins on superimposed T0 and T1 digital models. Using Bland-Altman and statistical analysis, all six measurements sites around each included tooth (n=594) acquired with both methods were compared.

RESULTS

Median ΔREC (5th and 95th percentile) acquired with a conventional clinical and digital method was 0.0mm (-2.0 - 1.0) and -0.4mm (-1.6 - 0.8), respectively (p<0.0001). The complete agreement between rounded digital and clinical ΔREC values was only 38%, revealing high disagreement also confirmed by Bland-Altman analysis with 95% limits of agreement ranging from -2.6 to 1.8mm. Absolute differences between the methods higher than 0.5 and 1 mm, was found in 61% and 38% of measurement sites, respectively.

CONCLUSIONS

The conventional clinical method for ΔREC evaluation exhibits lower sensitivity and accuracy than the digital method.

CLINICAL SIGNIFICANCE

The quality of both clinical and research data in periodontology and implantology can be considerably improved by the digital method while still preserving the compatibility with the conventional clinical method.

A novel computer-aided method for direct measurements and visualization of gingival margin changes

AIM

To introduce and validate a computer-aided method for direct measurements and visualization of gingival margin (GM) changes.

MATERIALS AND METHODS

The method consists of five main steps: digital model acquisition, superimposition, computer-aided GM detection, distance calculation between the GM curves, and visualization. The precision of the method was evaluated with repeatability and reproducibility analysis (n = 78 teeth). The method's repeatability was evaluated by repeating the algorithm on the same digital models by two operators. The reproducibility was evaluated by repeating the algorithm on two consecutive digital models obtained with a scan-rescan process at the same time point on the same patient. For demonstration, the proposed method for direct measurements of GM changes was performed on patients who had undergone root coverage procedures and treatment of periodontal disease.

RESULTS

Excellent repeatability was found for both intra- and inter-operator variability, that is, 0.00 mm, regarding computer-aided GM detection. The reproducibility of computer-aided GM detection evaluated on scan-rescan models was 0.10 mm.

CONCLUSIONS

The presented method enables the evaluation of GM changes in a simple, precise, and comprehensive manner through non-invasive acquisition and superimposition of digital models.

Treatment of multiple gingival recessions with concentrated growth factor membrane and coronally advanced tunnel technique via digital measurements: A randomized controlled clinical trial

Background/purpose

Research into biomaterial alternatives to connective tissue grafts (CTG) is a research hotspot. The purpose of this clinical trial was to compare the effectiveness of root coverage through tunnel technique with concentrated growth factor (CGF) vs CTG in treating multiple gingival recessions using digital measurements.

Materials and methods

Seventy Cairo Class I multiple gingival recessions (in 28 patients) were treated with either CGF or CTG combined with coronally advanced tunnel technique. Digital models were obtained at baseline, 2 weeks, 6 weeks, and 6 months post-op to compare the gain in gingival height, area, volume, and thickness. Tooth sensitivity, post-operative pain, and healing index were also recorded.

Results

Complete root coverage at 6 months post-op were 47.06% in the CGF group and 77.78% in the CTG groups. Mean root coverages were 80.55% and 96.18%, respectively. No statistical difference was demonstrated between the two groups in terms of gingival area gain at 2 weeks post-op, but the CTG group had greater increases in gingival height, area, volume, and thickness in the period after 2 weeks post-op. Pain scores were statistically significantly lower in the CGF group. At 6 months post-op, sensitivity scores decreased more significantly in the CTG group.

Conclusion

Digital measurements revealed post-operative gingival shrinkage was more pronounced in the CGF group than in the CTG group when combined with coronally advanced tunnel technique. Despite the ease-of-use and minimal post-operative discomfort, it is difficult to achieve similar root coverage outcomes to CTG when using CGF alone in treating multiple gingival recessions.

Methods and parameters for digital evaluation of gingival recession: a critical review

OBJECTIVES

The aim of the present review was to find, compare, and critically discuss digital methods for quantitative evaluation of gingival recessions dimensions.

DATA

Collection of articles and classification related to digital evaluation of gingival recessions.

SOURCES

A search of PubMed, Web of Science, Scopus, and reference lists of articles was conducted up to April 2021 STUDY SELECTION: Twenty-two articles used digital evaluation of gingival recessions dimensions. The methods in the included articles were extracted, compared, and categorized.

RESULTS

Digital measurements were performed on 2D intraoral photographs, 3D models, or cross-sections obtained from 3D models. Baseline measurement were performed for diagnostic and treatment planning and categorised into distance and area measurements. Follow-up evaluation of treatment was based either on repeating the "baseline" measurements and calculating differences or measuring differences directly on composite images, composed from two superimposed images obtained at two time-points. Direct measurements were categorised into distance, area, and volume measurements.

CONCLUSIONS

Digital evaluation predominantly means just digitalization of the established evaluation methods; therefore, increasing measurements accuracy and maintaining comparability with past studies. At present, a large variability of digital evaluation workflow among the included studies renders the comparison among different studies difficult if not impossible. The potential of digital evaluation seems not to have been fully exploited as only a few novel measurements and parameters introduced, i.e., volumetric evaluation of soft tissue dynamics. For reproducible and comparable studies in the future, the research should be aimed at evaluation, optimization and standardization of all phases of the digital evaluation.

CLINICAL SIGNIFICANCE

Digital evaluation, based on 3D image superimposition is a promising approach as it increases measurements accuracy, maintains compatibility with past studies and simultaneously introduces novel evaluation possibilities.

Modified coronally advanced tunnel technique with enamel matrix derivative in addition to subepithelial connective tissue graft compared with connective tissue graft alone for the treatment of multiple gingival recessions: prognostic parameters for clinical treatment outcomes

Objectives

To investigate factors that influence 12-month outcomes after treatment of multiple gingival recessions (GR) with modified coronally advanced tunnel (MCAT) and subepithelial connective tissue graft (SCTG) with enamel matrix derivative (EMD) (tests) or without (controls).

Materials and methods

Twenty patients with 150 GR were treated. Logistic regression models were used to identify baseline parameters that could predict 12-month average root coverage (ARC), complete root coverage (CRC), root esthetic coverage score (RES), gain in keratinized tissue width (KTW), and gain in gingival thickness (GT).

Results

The likelihood of ARC > 85% increased sevenfold (odds ratio [OR] = 7.33; 95% confidence interval [CI] = 2.43–12.12), of achieving CRC: 21-fold (OR = 21.23; 95% CI = 10.21–45.32), and of gaining RES = 10: tenfold (OR = 10.23; 95% CI = 5.78–32.23) in favor of EMD-treated sites. With each 1-mm² increase in baseline avascular exposed root surface area (AERSA), the odds of failure (ARC ≤ 85%, not achieving CRC and postoperative GT ≤ 2 mm) increased almost fourfold (OR = 3.56; 95% CI = 1.98–10.19), fourfold (OR = 4.23; 95% CI = 1.11–9.02), and nearly sixfold (OR = 5.76; 95% CI = 2.43–12.87), respectively. The greater the baseline GT, the more likely the chance of achieving CRC (OR = 10.23; 95% CI = 8.37–16.23) and RES = 10 (OR = 5.50; 95% CI = 3.34–16.43). All models exhibited fair to excellent discrimination and satisfactory calibration.

Conclusions

Based on logistic regression, EMD application improved postoperative ARC, CRC and RES; baseline AERSA predicted 12-month ARC, CRC, and GT gain, whereas baseline GT was a predictor of achieving CRC and perfect RES.

Clinical relevance

Additional use of EMD, lower baseline AERSA, and greater baseline GT significantly increase the odds of obtaining better outcomes 12 months after MCAT + SCTG technique.