Periodontal soft tissue root coverage procedures: a systematic review from the AAP Regeneration Workshop

BACKGROUND

This paper aims to create a "bridge" between research and practice by developing a practical, extensive, and clinically relevant study that translates evidence-based findings on soft tissue root coverage (RC) of recession-type defects to daily clinical practice.

METHODS

This review is prepared in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement based on the proposed focused questions. A literature search with no restrictions regarding status or the language of publication was performed for MEDLINE and EMBASE databases up to and including June 2013. Systematic reviews (SRs), randomized clinical trials, controlled clinical trials, case series, and case reports evaluating recession areas that were treated by means of RC procedures were considered eligible for inclusion through the three parts of the study (part I, an overview of the base of SRs; part II, an alternative random-effects meta-analyses on mean percentage of RC and sites exhibiting complete RC; and part III, an SR of non-randomized trials exploring other conditions not extensively evaluated by previous SRs). Data on Class I, II, III, and IV recessions, type of histologic attachment achieved with treatment, recipient- and donor-site anatomic characteristics, smoking-related outcomes, root surface conditions, tooth type and location, long-term effectiveness outcomes, unusual conditions that may be reported during conventional daily practice, and patient-centered outcomes were assessed as well.

RESULTS

Of the 2,456 potentially eligible trials, 234 were included. Data on Class I, II, III, and IV gingival recessions, histologic attachment achieved after treatment, recipient- and donor-site anatomic characteristics, smoking-related outcomes, root surface conditions/biomodification, tooth type and location, long-term effectiveness outcomes and unusual conditions that may be reported during conventional daily practice, and patient-centered outcomes (i.e., esthetic, visual analog scale, complications, hypersensitivity, patients perceptions) were assessed. Subepithelial connective tissue (CT)-based procedures and coronally advanced flap plus acellular dermal matrix grafts, enamel matrix derivative, or collagen matrix led to the best improvements of recession depth, clinical attachment level (CAL) gain, and keratinized tissue (KT). Some conditions, such as smoking and use of magnification, may affect RC outcomes.

CONCLUSIONS

All RC procedures can provide significant reduction in recession depth and CAL gain for Miller Class I and II recession-type defects. Subepithelial CT graft-based procedures provided the best outcomes for clinical practice because of their superior percentages of mean and complete RC, as well as significant increase of KT.

Interdental papilla loss: treatment by hyaluronic acid gel injection: a case series

OBJECTIVES

The purpose of this prospective clinical trial was to examine the clinical and patient outcomes following esthetic reconstruction of interdental papilla loss in anterior teeth, using an injectable, non-animal-based, hyaluronic acid gel.

MATERIALS AND METHODS

Ten systemically healthy adults, with at least one anterior site with class I or II interdental papilla loss, were recruited. Following local anesthesia, ∼0.2 ml of hyaluronic acid gel was injected directly into the base of the papilla. The injection was repeated twice 21 days later. Patients were seen monthly for follow-up. Lost papilla surface area was calculated from digital clinical photographs taken at baseline and at 4 and 6 months postoperatively. Differences in lost papilla surface area between baseline and postoperative time points were statistically analyzed. Participants completed questionnaires (satisfaction surveys).

RESULTS

Seventeen sites (13 maxillary, 4 mandibular) were treated in 9 females who completed the study. The lost inderdental papilla area at baseline and at the 4- and 6-month postoperative visits was 1.2 ± 1.8 mm(2) (mean ± SD), 0.6 ± 0.9 mm(2), and 0.7 ± 0.7 mm(2), respectively. Differences between baseline and postoperative visits were statistically significant (p < 0.0001). Two thirds of the patients would choose to undergo the procedure again.

CONCLUSIONS

Use of hyaluronic acid gel to treat interdental papilla loss resulted in significant improvement at 6 months. Patients expressed satisfaction with the obtained improvement and dissatisfaction with the associated procedure discomfort.

CLINICAL RELEVANCE

Treatment of interdental papilla loss (black triangle) by hyaluronic acid gel injection appears a promising modality to address this esthetic patient concern.

The effects of periodontal therapy on gingival crevicular fluid matrix metalloproteinase-8, interleukin-6 and prostaglandin E2 levels in patients with rheumatoid arthritis

OBJECTIVE

The aim of this study was to evaluate the effects of non-surgical periodontal therapy on gingival crevicular fluid levels of matrix metalloproteinase-8 (MMP-8), interleukin-6 (IL-6) and prostaglandin E2 (PGE2 ) in patients with rheumatoid arthritis (RA) with periodontal disease.

MATERIAL AND METHODS

Twenty-seven patients with gingivitis and periodontitis with RA, 26 patients with gingivitis and periodontitis that were systemically healthy and 13 periodontally and systemically healthy volunteers (control group) were included in this study. RA activity was assessed by disease activity score test. The clinical periodontal parameters, fasting venous blood and gingival crevicular fluid samples were obtained and gingival crevicular fluid MMP-8, IL-6 and PGE2 levels were evaluated at baseline and at 3 mo follow-up after non-surgical periodontal treatment.

RESULTS

Gingival crevicular fluid MMP-8, PGE2 and IL-6 levels were higher in all groups than the control group. Following periodontal therapy, there were significant decreases in gingival crevicular fluid MMP-8, PGE2 and IL-6 levels from patients with RA with periodontitis (p < 0.05). Plaque index, gingival index and bleeding on probing were significantly correlated with IL-6 and PGE2 at baseline and at 3 mo follow-up after non-surgical periodontal treatment.

CONCLUSION

Non-surgical periodontal therapy of patients with RA with periodontitis may provide beneficial effects on local inflammatory control via decreases in gingival crevicular fluid MMP-8, PGE2 and IL-6 levels.

Wound Healing of the Laterally Positioned Flap: A Histomorphometric Assessment

The aim of this study was to histomorphometrically assess the soft tissue anatomy in single gingival recessions (GR) treated with a laterally positioned flap (LPF). Five patients presenting maxillary first molars with GR to the apex of the buccal surface of the mesial-buccal root were invited to take part. The LPF-treated roots were removed en bloc (the root and the soft tissue covering the treated GR) 3 to 4 months postoperatively. Photomicrographs of Mallory trichrome stain sections were taken to allow reassessment of the specimens regarding the longitudinal dimensions of the crevicular/sulcular and junctional epithelia. The use of LPF resulted in new attachment with formation of crevicular epithelium, long junctional epithelium, and some connective tissue, re-establishing the normal anatomical characteristics of the soft tissues covering the previously exposed root.

Gingival Cyst of the Adult as Early Sequela of Connective Tissue Grafting

The subepithelial connective tissue graft (SCTG) is a highly predictable procedure with low complication rate. The reported early complications consist of typical postsurgical sequelae, such as pain and swelling. This case report describes the development and management of a gingival cyst following SCTG to obtain root coverage. Three weeks after SCTG procedure, a slightly raised, indurated, ~5 mm diameter asymptomatic lesion was evident. Excisional biopsy was performed and the histopathological evaluation confirmed the gingival cyst diagnosis. At the 1-year follow-up, the site had complete root coverage and normal tissue appearance and the patient remained asymptomatic.

Fourier transform Infrared spectroscopic characterization of mineralizing type I collagen enzymatic trivalent cross-links

The most abundant protein of bone's organic matrix is collagen. One of its most important properties is its cross-linking pattern, which is responsible for the fibrillar matrices' mechanical properties such as tensile strength and viscoelasticity. We have previously described a spectroscopic method based on the resolution of the Amide I and II Fourier transform Infrared (FTIR) bands to their underlying constituent peaks, which allows the determination of divalent and pyridinoline (PYD) collagen cross-links in mineralized thin bone tissue sections with a spatial resolution of ~6.3 μm. In the present study, we used FTIR analysis of a series of biochemically characterized collagen peptides, as well as skin, dentin, and predentin, to examine the potential reasons underlying discrepancies between two different analytical methodologies specifically related to spectral processing. The results identified a novel distinct FTIR underlying peak at ~1,680 cm(-1), correlated with deoxypyridinoline (DPD) content. Furthermore, the two different methods of spectral resolution result in widely different results, while only the method employing well-established spectroscopic routines for spectral resolution provided biologically relevant results, confirming our earlier studies relating the area of the underlying 1,660 cm(-1) with PYD content. The results of the present study describe a new peak that may be used to determine DPD content, confirm our earlier report relating spectroscopic parameters to PYD content, and highlight the importance of the selected spectral resolution methodology.

Altered bone material properties in HLA-B27 rats include reduced mineral to matrix ratio and altered collagen cross-links

Spondyloarthropathy and inflammatory bowel disease (IBD), which includes ulcerative colitis and Crohn's disease, are often associated with severe osteopenia/osteoporosis in both children and adults. HLA-B27 transgenic rats present a phenotype that includes severe colitis and severely accelerated alveolar bone loss. The purpose of this study was to evaluate long bone density status, systemic bone metabolic markers, and intrinsic bone material properties in HLA-B27 transgenic (TG) rats, and compare them with those of age- and sex-matched wild-type (WT) animals. The results indicate that in the HLA-B27 rat, an animal susceptible to both alveolar bone loss (ABL) and long bone osteopenia, there is a statistically significant negative correlation between ABL and long bone bone mineral density (BMD), as well as mineral/matrix ratio at active bone-forming trabecular surfaces. The TG animals had a lower mineral/matrix ratio and higher relative proteoglycan and advanced glycation end product (ϵ-N-Carboxymethyl-L-lysine) content and pyridinoline/divalent collagen cross-link ratio compared with WT. These results may provide better understanding of the interrelationship between osteoporosis and oral bone loss, the underlying causes of the inferior bone strength in the HLA-B27 transgenic animals, and could prove to be a useful model in the elucidation of the pathophysiology of spondyloarthropathy and IBD-associated osteopenia/osteoporosis and in the evaluation of pharmacological intervention(s) against such conditions.

Periodontal soft tissue root coverage procedures: a consensus report from the AAP Regeneration Workshop

BACKGROUND

Management of gingival recession defects, a common periodontal condition, using root coverage procedures is an important aspect of periodontal regenerative therapy. The goal of the periodontal soft tissue root coverage procedures group was to develop a consensus report based on the accompanying systematic review of root coverage procedures, including priorities for future research and identification of the best evidence available to manage different clinical scenarios.

METHODS

The group reviewed and discussed the accompanying systematic review, which covered treatment of single-tooth recession defects, multiple-tooth recession defects, and additional focused questions on relevant clinical topics. The consensus group members submitted additional material for consideration by the group in advance and at the time of the meeting. The group also identified priorities for future research.

RESULTS

All reviewed root coverage procedures provide significant reduction in recession depth, especially for Miller Class I and II recession defects. Subepithelial connective tissue graft (SCTG) procedures provide the best root coverage outcomes. Acellular dermal matrix graft (ADMG) or enamel matrix derivative (EMD) in conjunction with a coronally advanced flap (CAF) can serve as alternatives to autogenous donor tissue. Additional research is needed to do the following: 1) assess the treatment outcomes for multiple-tooth recession defects, oral sites other than maxillary canine and premolar teeth, and Miller Class III and IV defects; 2) assess the role of patient- and site-specific factors on procedure outcomes; and 3) obtain evidence on patient-reported outcomes.

CONCLUSIONS

Predictable root coverage is possible for single-tooth and multiple-tooth recession defects, with SCTG procedures providing the best root coverage outcomes. Alternatives to SCTG are supported by evidence of varying strength. Additional research is needed on treatment outcomes for specific oral sites. Clinical Recommendation: For Miller Class I and II single-tooth recession defects, SCTG procedures provide the best outcomes, whereas ADMG or EMD in conjunction with CAF may be used as an alternative.

Periodontitis in coronary heart disease patients: strong association between bleeding on probing and systemic biomarkers

AIM

Few studies have examined the relationship of individual periodontal parameters with individual systemic biomarkers. This study assessed the possible association between specific clinical parameters of periodontitis and systemic biomarkers of coronary heart disease risk in coronary heart disease patients with periodontitis.

MATERIALS AND METHODS

Angiographically proven coronary heart disease patients with periodontitis (n = 317), aged >30 years and without other systemic illness were examined. Periodontal clinical parameters of bleeding on probing (BOP), probing depth (PD), and clinical attachment level (CAL) and systemic levels of high-sensitivity C-reactive protein (CRP), fibrinogen (FIB) and white blood cells (WBC) were noted and analyzed to identify associations through linear and stepwise multiple regression analyses.

RESULTS

Unadjusted linear regression showed significant associations between periodontal and systemic parameters; the strongest association (r = 0.629; p < 0.001) was found between BOP and CRP levels, the periodontal and systemic inflammation marker, respectively. Stepwise regression analysis models revealed that BOP was a predictor of systemic CRP levels (p < 0.0001). BOP was the only periodontal parameter significantly associated with each systemic parameter (CRP, FIB, and WBC).

CONCLUSION

In coronary heart disease patients with periodontitis, BOP is strongly associated with systemic CRP levels; this association possibly reflects the potential significance of the local periodontal inflammatory burden for systemic inflammation.

Subpontic osseous hyperplasia: a case series and literature review

A subpontic osseous hyperplasia (SOH) is a slow-growing, non-neoplastic bone growth that uniquely affects mandibular posterior edentulous ridges underneath pontics of fixed partial dentures. An SOH can result in significant periodontal and restorative complications, however, it is usually corrected by surgical excision. This report presents a series of SOH cases, illustrates SOH management approaches, and reviews the literature on SOH clinical presentations.

Dimensional changes during early healing after a subepithelial connective tissue graft procedure

BACKGROUND

The subepithelial connective tissue graft (CTG) is a popular means to treat gingival recession and augment keratinized tissue. Studies exist that examine long-term outcomes of this procedure; however, changes in tissue dimensions during early healing (0 to 21 days postoperatively) are unknown. The aim of this study is to examine bucco-lingual tissue dimension (gingival tissue thickness [GT]) changes during early CTG healing using a non-invasive technique.

METHODS

Thirteen patients who had treatment planned for CTG on a single tooth were recruited for the study. Using a customized acrylic stent, GT was measured preoperatively, at surgery completion, and at 3, 7, 14, and 21 days postoperatively. CTG was performed using an envelope technique. GT changes were analyzed by repeated-measures analysis of variance.

RESULTS

All CTG procedures were considered successful with no postoperative complications. GT increased 1.5 mm immediately after surgery (baseline) compared to the preoperative measurement. GT increased on average 96%, 47%, and 2% compared to baseline at days 3, 7, and 14, respectively. Day 3 and day 7 measurements were significantly different from baseline (P <0.001). At day 21, GT decreased 15% compared to baseline, with an average increase of 1.29 mm from preoperative measurements.

CONCLUSIONS

The early postoperative healing of CTGs used for root coverage exhibits a significant but transient increase in bucco-lingual tissue dimension. The observed increase in bucco-lingual tissue dimension subsides by the end of the second postoperative week.

Peri-implant versus periodontal wound healing

AIM

Peri-implant gingival healing following one-stage implant placement was investigated and compared to periodontal healing.

METHODS

Healing at surgical sites [implant (I) and adjacent teeth (T+)] was compared to non-operated tooth (T-) in non-smokers receiving one-stage implant. Periodontal Indices (PI, GI) were recorded at surgery and up to 12 weeks post-operatively. Peri-implant (PICF) and gingival crevicular fluids (GCF) were analysed for cytokines, collagenases and inhibitors. Data were analysed by linear mixed model regression analysis and repeated measures anova.

RESULTS

Forty patients (22 females; 21-74 years old) completed the study. Surgical site GI, increased at week 1, decreased significantly during early healing (weeks 1-3; p = 0.0003) and continually decreased during late healing (weeks 6-12) for I (p < 0.01). PICF volume decreased threefold by week 12 (p = 0.0003). IL-6, IL-8, MIP-1β and TIMP-1 levels significantly increased at surgical sites at week one, significantly decreasing thereafter (p < 0.016). Week one IL-6, IL-8 and MIP-1β levels were ~threefold higher and TIMP-1 levels 63% higher, at I compared to T+ (p = 0.001).

CONCLUSION

Peri-implant gingival healing, as determined by crevicular fluid molecular composition, differs from periodontal healing. The observed differences suggest that peri-implant tissues, compared to periodontal tissues, represent a higher pro-inflammatory state.

Root caries: a periodontal perspective

BACKGROUND AND OBJECTIVE

A prevailing dental problem in the periodontal patient is root caries. Specifically, periodontal involvement often results in root surfaces becoming exposed and at risk for this condition. Periodontal therapy often leads to increased gingival recession as well, and the associated increased root caries risk may compromise the long-term success and survival of periodontally treated teeth.This narrative review will address the topic of root caries in the periodontal patient, focusing on unmet research needs.

MATERIAL AND METHODS

The Medline database was searched to identify items dealing with root caries, in terms of clinical features, diagnosis, pathogenic mechanisms and histopathology, as well as epidemiology, focusing then on the relationship between root caries and periodontal disorders.

RESULTS

Although there is extensive literature on root caries, consensus is lacking regarding certain aspects, such as diagnostic criteria, prevalence within populations and indisputable risk factors. Advancing age could be an aggravating factor in susceptibility to root caries for the periodontal patient; however, definitive evidence in this regard is still missing. Similarly, full awareness of the increased risk of root caries in patients with periodontal disease or long-term periodontal treatment appears to be still lacking.

CONCLUSION

Research regarding root caries in age-specific (elderly) periodontal patients is needed. Improved oral hygiene practices, locally applied preventive measures, good dietary habits and regular dental check-ups are crucial approaches to prevent both periodontal disease progression and root caries. Periodontal patients with root exposure should follow a strict root caries prevention protocol, as an integral component of their periodontal maintenance therapy.

Determinants of alveolar ridge preservation differ by anatomic location

AIM

To investigate and compare outcomes following alveolar ridge preservation (ARP) in posterior maxilla and mandible.

METHODS

Twenty-four patients (54 ± 3 years) with single posterior tooth extraction were included. ARP was performed with freeze-dried bone allograft and collagen membrane. Clinical parameters were recorded at extraction and re-entry. Harvested bone cores were analysed by microcomputed tomography (micro-CT), histomorphometry and immunohistochemistry.

RESULTS

In both jaws, ARP prevented ridge height loss, but ridge width was significantly reduced by approximately 2.5 mm. Healing time, initial clinical attachment loss and amount of keratinized tissue at extraction site were identified as determinants of ridge height outcome. Buccal plate thickness and tooth root length were identified as determinants of ridge width outcome. In addition, initial ridge width was positively correlated with ridge width loss. Micro-CT revealed greater mineralization per unit volume in new bone compared with existing bone in mandible (p < 0.001). Distributions of residual graft, new cellular bone and immature tissue were similar in both jaws.

CONCLUSION

Within the limitations of this study, the results indicate that in different anatomic locations different factors may determine ARP outcomes. Further studies are needed to better understand determinants of ARP outcomes.

Effects of a new implant abutment design on peri-implant soft tissues

The purpose of this study was to assess the effects of a modified implant abutment design on peri-implant soft and hard tissues in dogs. Three months after extraction of mandibular premolar teeth, 3 dental implants were placed in each side of the jaw using a 1-stage approach. Implants on one side of the mandible received standard abutments (control), and implants on the contralateral side received modified, patented, grooved abutments (test). Two months after implant placement, animals were euthanized and specimens were prepared for histologic and histomorphometric assessment. The linear distance (in micrometers) was measured from the implant shoulder (IS) to the following landmarks: gingival margin (GM; distance IS-GM), most apical position of the junctional epithelium (JE; distance IS-JE), and bone crest (BC; distance IS-BC). Percent of bone-to-implant contact was also measured. Histologic assessment revealed that all implants were osseointegrated and that interimplant gingival fibers between test abutments appeared to be more numerous and organized than control abutments. The IS-GM and IS-JE distances in test implants were greater than the corresponding distances in control implants (P = .024 and P = .015, respectively), whereas crestal bone loss (IS-BC) was greater for control implants than test implants (P = .037). There were no differences between control and test implants in bone-to-implant contact (P = .69), which averaged close to 50%. These results suggest that the modified groove design incorporated in standard abutments confers both soft and hard tissue benefits.

Excessive gingival display: treatment by a modified lip repositioning technique

AIM

The objective of this prospective study was to investigate outcomes of a lip repositioning technique for the treatment of excessive gingival display.

MATERIALS AND METHODS

Thirteen consecutively treated patients with excessive gingival display were treated with a modified lip repositioning technique. Treatment consisted of the removal of two strips of mucosa, bilaterally to the maxillary labial frenum and coronal repositioning of the new mucosal margin. The clinical dimensions of gingival display, upper lip and vermillion length were measured at baseline, 3 and 6 months post-operatively. Subjects completed surveys to evaluate satisfaction with outcomes.

RESULTS

The baseline gingival display of 5.8 ± 2.1 mm significantly decreased to 1.4 ± 1.0 mm at 3 months (p < 0.0001) and was maintained until 6 months (1.3 ± 1.6 mm). The reduction in gingival display strongly correlated to the combined change in upper lip and vermillion length (r(2)  = 0.60, p = 0.0018). Subjects were satisfied with their smile after surgery and would likely choose to undergo the procedure again (92%). The worst part of undergoing the procedure was the discomfort or the inability to move the lip during the early healing (69%).

CONCLUSION

Treatment of excessive gingival display by means of a modified lip repositioning technique results in high level of patient satisfaction and predictable outcomes that are stable in the short term.

Non-surgical periodontal therapy reduces coronary heart disease risk markers: a randomized controlled trial

AIM

Periodontal disease elevates systemic inflammatory markers strongly associated with coronary heart disease (CHD) risk. The aim of this randomized controlled trial was to investigate the effect of non-surgical periodontal therapy on systemic C-reactive protein (CRP), fibrinogen and white blood cells in CHD patients.

MATERIALS AND METHODS

Angiographically proven CHD patients with periodontitis (n = 317) were randomized to intervention (n = 212) or control group (n = 105). Primary outcome was reduction in serum CRP levels; secondary outcomes were reductions in fibrinogen and white blood cells. Periodontal treatment included scaling, root planing and oral hygiene instructions. Periodontal and systemic parameters were assessed at baseline and at 2-month follow-up. Intent-to-treat (ITT) analysis was performed.

RESULTS

Study was completed by 246 subjects (intervention group = 161; control group = 85). Significant improvements in periodontal and systemic parameters were observed in intervention group. The number of subjects with CRP > 3mg/L in intervention group decreased by 38% and in control group increased by 4%. ITT analysis gave a significant (χ(2) =4.381, p = 0.036) absolute risk reduction of 12.5%.

CONCLUSION

In CHD patients with periodontitis, non-surgical mechanical periodontal therapy significantly reduced systemic levels of C-reactive protein, fibrinogen and white blood cells.