Subgingival acellular dermal matrix allograft for the treatment of gingival recession: a case report

A Novel Prehydrated Porcine-Derived Acellular Dermal Matrix: A Histological and Clinical Evaluation

It is well known that soft tissue quality and quantity around dental implants is of paramount importance for later peri-implant health. For this purpose, the clinical and histological outcomes of the peri-implant mucosa, following soft tissue augmentation for soft tissue improvement with a novel prehydrated porcine acellular dermal matrix graft (PPADMG) in conjunction with simultaneous implant placement, were evaluated in this case series. Twenty-two patients were included in the study. They underwent a late implant placement protocol combined with PPADMG for soft tissue augmentation. A punch biopsy was taken at the time of uncovery of the submerged healed implant after a mean of 157 days healing time. Supracrestal soft tissue height (STH) was measured at the time of implant placement and uncovery. All sites showed a clinical increase in STH. The histological structure of the biopsies resembled a similar structure as found in the healthy oral mucosa. No unexpected tissue reactions could be found. Within the limits of this clinical and histological study, it may be concluded that STH improvement with this novel porcine-derived acellular dermal matrix, in combination with simultaneous implant placement, is a viable option to create a peri-implant tissue thickness and stability.

Intra-marrow penetrations and root coverage outcomes: a systematic review

BACKGROUND

Intra-marrow penetrations (IMPs) have been performed during guided tissue regeneration (GTR) procedures with reported clinical benefits. The aim of this systematic review was to investigate the use and effect of IMPs during root coverage procedures.

METHOD

A broad search for human and animal studies was performed on PubMed, Cochrane Database of Systematic Reviews and Cochrane Central Registry of Controlled Trials and Web of Science, following a registered review protocol (PROSPERO). All prospective study designs, case series and case reports on gingival recession treatment (follow-up ≥ 6 months) that employed IMPs were included. Root coverage, complete root coverage prevalence, and adverse effects were recorded, and risk of bias was assessed.

RESULTS

Of 16,181 screened titles, 5 articles (all of them human studies) met inclusion criteria. All studies (including two randomized clinical trials) treated Miller class I and II recession defects, using coronally advanced flap with IMPs alone or in conjunction with GTR protocols. Therefore, all treated defects received IMPs and no studies compared protocols with and without IMPs. Outcomes were indirectly compared with existing root coverage literature. Mean root coverage was 2.7 mm and 68.5% at 6.8 months (median: 6 months, range 6-15 months) for sites treated with IMPs.

CONCLUSION

IMPs are rarely used during root coverage procedures, have not been associated with intra-surgical or wound healing adverse effects and have not been investigated as independent factor. Future clinical studies are needed to directly compare treatment protocols with and without IMPs and investigate the potential benefits of IMPs for root coverage.

A split-mouth randomised controlled trial comparing the clinical effects of MVISTA with chorion membrane or connective tissue graft in multiple gingival recessions

Objectives

Modified form of VISTA (MVISTA), a novel surgical procedure, aims at comprehensive root coverage that maintains the inner continuity of the periosteum and papilla. This technique incorporates any regenerative graft material within the tunnel. The objective of study is to compare the MVISTA for treating multiple adjacent gingival recessions and chorion membranes or grafts of connective tissues.

Materials and methods

This is a split-mouth type randomized trial. In this trial total of 18 patients were considered. The patients in this trial had multiple adjacent, gingival recessions of Miller's Classes I/II, and they were randomized to either the MVISTA with chorion membrane (test) or connective tissue graft (CTG) (control) group. A baseline and one year after surgery were considered for recording to mean root coverage (MRC), complete root coverage (CRC), and clinical periodontal parameters. An intragroup comparison was made.

Results

The intragroup comparison of recession depth baseline and 12 months after-surgery record found a significant difference between the two groups (P = 0.00). In the postoperative condition, the depth of recession reduction was higher in the test group than in the control group. However, from a statistical perspective, the difference was insignificant (P > 0.05). At the end of the year, it was found that the width of the keratinized tissue had increased significantly (P < 0.05). The MRC in the test group was significantly higher (91.33 %±8.17 %) than that in the control group (89.46 %±11.22 %) (P > 000). At the end of 1 year, the test group showed 66.67 % CRC compared to 44.44 % in the control group. The gingival phenotype displayed statistically significant improvement in the test group (p = 0.004). PD and CAL showed statistically nonsignificant outcomes (P > 0.05).

Conclusions

As far as multiple adjacent gingival recession treatment is concerned, MVISTA with chorion membrane treatment enhanced the gingival phenotype, restored complete root coverage (66.6%), and increased the width of keratinized tissue. CTG and CM demonstrated good root coverage results; the latter might be used as a substitute graft to treat multiple recessions.

Quantity of Acellular Dermal Matrix in Immediate Breast Reconstruction and Outcomes

PURPOSE

This study aimed to determine the impact of the quantity of acellular dermal matrix (ADM), "ADM burden," used in implant-based breast reconstruction on infection, drain duration, and seroma formation.

METHODS

A single-institution, retrospective review from 2015 to 2020 was conducted for patients who underwent immediate, implant-based breast reconstruction after mastectomy. Three cohorts were generated based on the amount of ADM used: (1) total ADM, (2) sling ADM, and (3) no ADM.

RESULTS

In total, there were 374 patients who satisfied the inclusion criteria yielding 641 breasts with 143, 432, and 66 breasts in the total ADM, sling ADM, and no-ADM groups, respectively. The no-ADM group had higher mastectomy weights (788.4 g) than the sling (654.2 g) and total ADM (503.4 g) groups (F = 10.8, P < 0.001). Total ADM had higher rates of explantation secondary to infection compared with no ADM (P < 0.001). Linear regression analysis for drain duration was significant for body mass index (P < 0.0001) but not for ADM quantity (P = 0.52). Logistic regression analysis demonstrated a higher risk of infection in the total ADM group (odds ratio [OR], 5.4; P < 0.0001). Diabetes mellitus was a risk factor for both infection (OR, 3.6; P = 0.05) and seroma formation (OR, 0.04; P = 0.04).

CONCLUSIONS

Higher ADM burden is associated with an increased risk of infections and device explantation secondary to those infections. Although ADM has created new avenues in breast reconstruction, these findings indicate a need to evolve the technique to minimize the ADM burden. By doing so, patients can minimize their risk of postoperative complications while reducing the financial impact on institutions.

In Vivo Comparison of Three Human Acellular Dermal Matrices for Breast Reconstruction

BACKGROUND/AIM

Acellular dermal matrices (ADMs) have become popular in implant-based breast reconstruction. The aim of this study was to compare three commonly used ADM products in vivo in an animal model.

MATERIALS AND METHODS

The nucleic acid content (residual double-stranded DNA) and the levels of the remaining growth factors after decellularization were measured for each ADM. Cytocompatibility with ADMs was documented using NIH 3T3 mouse fibroblast cells. In vivo, the implanted ADMs were histologically evaluated at 1, 2, 3, and 6 months (n=5) using male 8-week-old Sprague-Dawley rats.

RESULTS

Fibroblasts grew in the SureDerm HD and DermACELL with no cytotoxicity. In a rat model, SureDerm HD and DermACELL incorporated more readily into the surrounding host tissue, as measured by rapid cell influx and collagen deposition, and showed more delayed tissue remodeling with decreased matrix metalloproteinases levels compared to AlloDerm.

CONCLUSION

SureDerm HD and DermACELL can be used as biological materials for breast reconstruction.

Regenerative Potential of Enamel Matrix Protein Derivative and Acellular Dermal Matrix for Gingival Recession: A Systematic Review and Meta-Analysis

Objective: The purpose of this study was to assess the clinical effectiveness of using a combination of enamel matrix protein derivative and acellular dermal matrix in comparison to acellular dermal matrix alone for treating gingival recessions. Methods: The Cochrane Library (Wiley), PubMed by Medline (NLM), Medline (EBSCO), and Embase (Ovid) databases were searched for entries up to April 2020. Only clinical trials were included. Primary outcomes were root coverage (%), changes in keratinized tissue width and recession (mm). Meta-analysis was conducted for root coverage, changes in keratinized tissue width, recession, clinical attachment level and probing depth. Results: Four studies were selected for the analysis. In primary outcomes, root coverage, change in keratinized tissue width and recession analysis showed a mean difference of 4.99% (p = 0.11), 0.20 mm (p = 0.14) and 0.13 mm (p = 0.23) respectively between the two groups. Secondary outcomes analysis also exhibited a statistically insignificant difference between the test and control group with mean difference of 0.11 mm (p = 0.32) in clinical attachment level gain and -0.03 mm (p = 0.29) in probing depth reduction analysis. Conclusions: Within the limits of this study, enamel matrix protein derivative combined with acellular dermal matrix used for treating gingival recession defects resulted in no beneficial effect clinically than acellular dermal matrix only.

A novel soft tissue cone-beam computed tomography study in the evaluation of gingival thickness associated with subepithelial connective tissue graft versus acellular dermal matrix in the management of gingival recession: A clinical study

BACKGROUND

Dental esthetic awareness among patients led the clinicians to introduce newer materials and predictable techniques that satisfy the patients' esthetic demands.

AIM

To evaluate and compare the efficacy of subepithelial connective tissue graft (SECTG) and acellular dermal matrix (ACDM) allograft in the treatment of Millers Class I or Class II recession with the determination of gingival thickness using an impertinent method, soft tissue cone-beam computed tomography (ST-CBCT).

MATERIALS AND METHODS

A split-mouth study with a total of ten patients with bilateral Millers class I or class II recession is randomly assigned by a coin toss method as Group I (SECTG) and Group II (ACDM) along with coronally advanced flap. Clinical parameters including recession height (RH), recession width (RW), probing depth, clinical attachment level (CAL), and height of keratinized tissue (HKT) were evaluated at baseline, 90th day, and 180th day for both groups. The thickness of keratinized tissue (TKT) was determined by most reliable, predictable and noninvasive method called ST-CBCT.

RESULTS

Statistically significant reduction in RH and RW, gain in CAL, and increase in HKT and TKT in both Group I and Group II were seen in 90th day and 180th day. However, when both Group I and Group II were compared between 0 and 180th day, the change in RH and RW, gain in CAL, and increase in HKT and TKT did not show any statistically significant change.

CONCLUSION

The present study suggested that root coverage with both SECTG and ACDM is very predictable procedure and it is stable for 6 months. ST-CBCT is a newer dimension in periodontal imaging and will certainly aid clinicians in the execution of various treatment modalities with increased predictability.

A randomized split mouth clinical study to compare the clinical outcomes of subepithelial connective graft and acellular dermal matrix in Miller's Class I recession coverage therapy

Background:

According to the American Association of Periodontology, subepithelial connective tissue graft (SCTG) is one the most reliable surgical technique available for the treatment of gingival recession (GR) with Miller's Class I defect. However, due to its various disadvantages, alternate grafts such as acellular dermal matrix (ADM) grafts have been introduced for recession coverage. The present study compares the clinical outcome of these two grafts in treating Miller's Class I GR.

Materials and Methods:

All the 15 patients participated in the study who had totally 30 bilateral Miller's Class I GR were divided randomly into SCTG group and ADM group each containing 15 defects. In the SCTG group, coronally advanced flap (CAF) with SCTG was performed, and in ADM group, CAF with ADM was done. Clinical parameters were measured on the day of surgery (baseline) and after 6 months. Data collected were statistically analyzed using paired and unpaired t-tests.

Results:

The analysis of the data collected at the baseline and 6 months later showed that there were no statistically significant differences in the recorded clinical parameters such as probing pocket depth, clinical attachment loss, and GR depth. ADM group showed a better color match than the SCTG group, while SCTG group achieved more keratinized tissue width than ADM group.

Conclusion:

From the outcome of the current study, we can conclude that ADM is an efficient substitute for SCTG for treating Miller's Class I GR. However, additional studies with greater number of samples and lengthier follow-up periods are necessary to validate the present inference.

Root coverage using coronally advanced flap with porcine-derived acellular dermal matrix or subepithelial connective tissue graft: a randomized controlled clinical trial

OBJECTIVE

The aim of this study is to investigate the use of a porcine-derived acellular dermal matrix (MD) in root coverage procedures combined with extended coronally positioned flap (eCAF), in comparison to the subepithelial connective tissue graft (SCTG) associated with the eCAF.

MATERIAL AND METHODS

Eighteen adult patients presenting bilateral type 1 gingival recession were randomly assigned to SCTG or MD groups. Clinical and patient-based outcomes were recorded at 3 and 6 months after the surgical procedure.

RESULTS

Both groups showed a significant reduction in the mean recession height of 3.33 ± 0.89 mm to 1.24 ± 1.10 mm (MD) and 3.21 ± 0.8 mm to 0.83 ± 0.86 mm (SCTG) without difference between groups. Six patients in the test group and eight in the control group obtained complete root coverage. The keratinized tissue height and thickness (KTT) showed a significant increase after 3 and 6 months in both groups. The average KTT gains were 0.39 ± 0.4 mm (MD) and 0.51 ± 0.5 mm (SCTG) (p < 0.05). Performing multivariate analysis suggests that MD addition to coronally advanced flaps may be similar to SCTG.

CONCLUSION

The MD had similar results in comparison to SCTG and in the context of reducing patient morbidity it can be used as an alternative for the treatment of gingival recessions.

CLINICAL RELEVANCE

The SCTG is the gold standard therapy for root coverage. The MD has been widely used in mucogingival surgery as a substitute for SCTG and proposed similar results. A substitute is very important for clinicians and patients. It will give a better postoperative and possibilities to treat multiples recession. (Clinicaltrials.gov Identifier: NCT03675334).

Root coverage stability with acellular dermal matrix in multiple gingival recessions in esthetic zone: A clinical case report with 12-year follow-up

The importance of surgical intervention for the maintenance of long-term results by root coverage of multiple gingival recessions in an esthetic area treated with a tissue substitute (acellular dermal matrix [ADM]-Alloderm^®) is widely required. The present case report highlights the effectiveness of the ADM for the treatment of multiple recession defects in a female patient with Class I and II gingival recession in relation to maxillary anterior associated with esthetics and dentin hypersensitivity demands. The root coverage rate for the anterior area showed greater value with 70% of coverage; at 90 days and 2 and 12 years of follow-up, it showed 70.5%, 79%, and 77%, respectively. Conversely, for the posterior area, these rates were 68.5%, 63%, and 57% for the same follow-up periods. Results regarding gain of keratinized tissue demonstrated superior values for the anterior area, namely 3.92, 3.34 and 3.22 mm at 90 days and 2 and 12 years. These values for the posterior area were 0.54 mm, 2.41, and 1.87 mm, respectively. These findings suggest that the tissue substitute Alloderm^® showed excellent long-term results for areas of multiple recessions, providing root coverage and stability of keratinized tissue gain. After this long period of evaluation, some local factors associated with recurrence of gingival recessions were detected, and a lack of proper periodontal maintenance care was observed. However, esthetic and functional outcomes achieved with surgical procedure were maintained.

Experimental and clinical studies on plastic periodontal procedures

We have compiled, in this Periodontology 2000 review, all Latin American literature on experimental and clinical studies of periodontal plastic procedures. The body of literature on this subject has led to a discussion of the features and treatment outcomes of root-coverage procedures. Over time, knowledge on periodontal plastic procedures has become less empirical and more supportive of the clinical management of recession-type defects. Gingival recession etiology, animal studies, free gingival grafts, pedicle flaps (semilunar, laterally positioned, and coronally positioned), and subepithelial connective tissue grafts are extensively reviewed. The use of allografts as an alternative to subepithelial connective tissue grafts, the treatment of multiple gingival recessions, and the rationale for use of guided tissue regeneration and enamel matrix derivative in plastic periodontal procedure is discussed. We also assess how smoking can affect the treatment outcomes in plastic surgery procedures. Minimally invasive procedures are of great value in improving the features of the final tissues. The following aspects identified in this compilation were of great interest: (a) some factors, anatomical in nature, favor the formation of root recessions, but it is the inflammatory process (caused by the presence of biofilm and/or by traumatic toothbrushing) that is responsible for the development of root recessions; and (b) pedicle flap procedures (especially the coronally positioned flap) are extremely versatile and have the most predictable outcome of all root-coverage procedures, especially when combined with subepithelial connective tissue grafting and/or allogeneic grafts. In summary: subepithelial connective tissue grafting is considered as the first option to augment gingival width and thickness, and it may provide better long-term results; the same principles of root-coverage procedures in individual sites appear be used in clinical practice also for multiple-recession type defects; an allograft is an efficient alternative to a subepithelial connective tissue graft and, when it is the treatment option of choice, the use of wide, extended flaps should be considered; because of the superiority of plastic periodontal procedures over guided tissue regeneration and the technical difficulty of the latter, guided tissue regeneration has become obsolete for root-coverage procedures; there is rather a large body of evidence attesting that smoking negatively influences root-coverage procedures, especially subepithelial connective tissue grafts; and minimally invasive techniques may be of great value for improving the results obtained with plastic periodontal procedures, but these techniques need to be better addressed in clinical trials, both in terms of the quality and quantity of the new tissue generated.

Clinical, histological, and ultrasound follow-up of breast reconstruction with one-stage muscle-sparing "wrap" technique: A single-center experience

BACKGROUND

Prepectoral implant placement and complete coverage with porcine acellular matrix after mastectomy is a new concept in breast surgery presented in few cases in the literature. This paper aimed to present our single-center experience in one-stage breast reconstruction muscle-sparing "wrap" technique by evaluating clinical and aesthetic outcomes, ultrasound and histological examination, and patient quality of life.

METHODS

From January 2014 to January 2017, 52 patients (40 unilateral, 12 bilateral) underwent one-stage muscle-sparing breast reconstructions with Braxon^® acellular dermal matrix and implant. In 3 patients, a surgical biopsy and histological examination with immunohistochemical analysis of the periprosthetic tissue were performed. All patients underwent breast ultrasound examination, and the occurrence of capsular contracture was assessed through the Baker classification and by measuring the mammary compliance scores with the Antoon Paar Mammary compliance system. Breast appearance was evaluated using a visual analogue scale (VAS) and in terms of quality of life using the EOCRT QLQ C-30 and QLQ BR-23 questionnaires.

RESULTS

Early and late postoperative complications are reported. Histological and ultrasound evaluation showed a complete integration of the matrix. According to the VAS scale, the EOCRT QLQ C-30, and QLQ BR-23, patients' satisfaction resulted in a high score in terms of quality of life and aesthetic outcomes.

CONCLUSION

The results of this new surgical technique in selected cases are promising in terms of effectiveness and low rate of postoperative complications, but further long-terms evaluations are required.

Development of a new method for the preparation of an acellular allodermis, quality control and cytotoxicity testing

Demand for use of acellular allodermis is high but commercially appropriate products are not used routinely because of very high price and limited availability. These facts did motivate us to prepare acellular allodermis using a new, simple and less expensive method. We have developed a original method for preparation of acellular allogeneic dermis based on action of a proteolytic enzyme in combination with distilled water. Hypotonic environment in comparison with SDS or Triton ansure no toxicity of the final product. Trials for determination of optimal trypsin concentrations, temperature and time of action were performed. According to our results, the use of 2.5% trypsin/EDTA solution overnight at +4 °C was proving to be optimal. The histology confirmed absence of cells in the prepared dermis. No toxicity of final acellular dermis was confirmed by three independent tests (agar diffusion test contact cytotoxicity test and grow curve). The prepared acellular dermis seems to be suitable not only for direct clinical use, but it can be used as a scaffold for cell cultivation as well.

Evaluation of the zone of keratinized tissue using exposed acellular dermal matrix over tooth extraction sites: a randomized controlled clinical trial

BACKGROUND

The presence of an adequate zone of keratinized tissue has been associated with implant health. This study evaluated the zone of keratinized tissue using exposed acellular dermal matrix (ADM) over extraction sites.

MATERIAL AND METHODS

Fifteen sites received ADM, and fifteen control sites received no biomaterial. All sites were sutured with no attempt to achieve primary closure. Initial measurements of buccal and lingual keratinized tissue were taken from the mucogingival line (MGL) to the most coronal gingival margins. Final measurements were taken from the buccal MGL to the lingual MGL 90 days after surgery. Gingival biopsies were taken before implant placement.

RESULTS

Test and control groups exhibited a mean value of 4.40 ± 1.45 mm and 1.40 ± 1.40 mm, respectively. The newly formed tissue revealed similar histological aspect of normal keratinized tissue.

CONCLUSION

Exposed ADM used over tooth extraction sockets can predictably be used to increase the zone of keratinized tissue.

The use of a biostatic fascia lata thigh allograft as a scaffold for autologous human culture of fibroblasts--An in vitro study

The method for covering gingival recession defects and augmenting keratinized gingiva involves the use of autogenuous connective tissue grafts obtained from palatal mucosa in combination with various techniques of flap repositioning or tunnel techniques. In the case of multiple gingival recession defects the amount of connective tissue available for grafting is insufficient. Therefore, the use of substitutes is necessary. The most widely used material in recent years has been the acellular dermal matrix allograft. The disadvantage of its application lies in the absence of cells and blood vessels, which increases incorporation time. Primary cultured human autologic fibroblasts are commonly used to optimize the healing process. The aim of this study was to examine the in vitro biocompatibility of human fascia lata allograft as a new scaffold for primary cultured human autologic fibroblasts. For that, a fibroblast culture obtained from a fragment of gingival tissue taken from the hard palate mucosa of a subject was used. After 14 days the colony cells were inoculated on a fragment of human fascia lata allograft. After a further 7 days of incubation the material was frozen, cut and prepared for histochemical examination. After two weeks of incubation, and 7 days after inoculation on a fragment of fascia lata allograft numerous accumulations of the cultured fibroblast were found that had a typical structure and produced collagen fibres. A human fascia lata allograft can be used as a scaffold for primary cultured human autologic fibroblasts. Further studies should confirm the clinical efficacy of this solution.

A modified surgical technique for root coverage with an allograft: a 12-month randomized clinical trial

BACKGROUND

The aim of this randomized controlled clinical study is to investigate whether a modified surgical technique could provide better results for root coverage and greater amounts of keratinized tissue (KT) with the acellular dermal matrix graft (ADMG).

METHODS

Fifteen bilateral Miller Class I or II gingival recessions (GRs) were selected. The recessions were treated and assigned randomly to the test group (TG), and the contralateral recessions were assigned to the control group (CG). The ADMG was used in both groups with differences in the graft positioning between them. The following clinical parameters were measured before the surgeries and after 12 months: 1) probing depth; 2) relative clinical attachment level; 3) GR; 4) thickness of KT (TKT); and 5) KT width. A new parameter, the GR area (GRA), was measured in standardized photographs using a special device and software.

RESULTS

There was no significant difference between groups in KT width and TKT parameters at the 12-month postoperative period. However, there was a significant difference between the gains in GR (ΔGR) and GRA (ΔGRA), favoring the TG after 12 months. The TG presented ΔGR = 3.04 ± 0.29 mm and ΔGRA= 38,919 ± 9,238 pixel square values (pix(2)), and the CG presented ΔGR= 2.61 ± 0.41 mm and ΔGRA= 22,245 ± 9,334 pix(2) (P <0.05 and <0.001, respectively).

CONCLUSIONS

Both techniques were successful. The TG treatment was more effective in reducing GR and GRA. The flap and graft position may be of importance in root coverage procedures outcome.

A comparative clinical study of the efficacy of subepithelial connective tissue graft and acellular dermal matrix graft in root coverage: 6-month follow-up observation

Aims:

The purpose of this study was to compare the clinical efficacy of subepithelial connective tissue graft and acellular dermal matrix graft associated with coronally repositioned flap in the treatment of Miller's class I and II gingival recession, 6 months postoperatively.

Settings and Design:

Ten patients with bilateral Miller's class I or class II gingival recession were randomly divided into two groups using a split-mouth study design.

Materials and Methods:

Group I (10 sites) was treated with subepithelial connective tissue graft along with coronally repositioned flap and Group II (10 sites) treated with acellular dermal matrix graft along with coronally repositioned flap. Clinical parameters like recession height and width, probing pocket depth, clinical attachment level, and width of keratinized gingiva were evaluated at baseline, 90^th day, and 180^th day for both groups. The percentage of root coverage was calculated based on the comparison of the recession height from 0 to 180^th day in both Groups I and II.

Statistical Analysis Used:

Intragroup parameters at different time points were measured using the Wilcoxon signed rank test and Mann–Whitney U test was employed to analyze the differences between test and control groups.

Results:

There was no statistically significant difference in recession height and width, gain in CAL, and increase in the width of keratinized gingiva between the two groups on the 180^th day. Both procedures showed clinically and statistically significant root coverage (Group I 96%, Group II 89.1%) on the 180^th day.

Conclusions:

The results indicate that coverage of denuded root with both subepithelial connective tissue autograft and acellular dermal matrix allograft are very predictable procedures, which were stable for 6 months postoperatively.

A Randomized comparative clinical study of two surgical procedures to improve root coverage with the acellular dermal matrix graft

AIM

This randomized, controlled, clinical study compared two surgical techniques for root coverage with the acellular dermal matrix graft (ADMG) to evaluate which procedure could provide better root coverage and greater amounts of keratinized tissue.

MATERIALS AND METHODS

Fifteen pairs of bilateral Miller Class I or II gingival recessions were treated and assigned randomly to the test group, and the contra-lateral recessions were assigned to the control group. The ADMG was used in both groups. In the control group, the graft and flap were positioned at the level of the cemento-enamel junction (CEJ), and in the test group, the graft was positioned 1 mm apical to the CEJ and the flap 1 mm coronal to the CEJ. The clinical parameters were taken before the surgeries and after 6 months. The gingival recession area, a new parameter, was measured in standardized photographs through a special device and software.

RESULTS

There were statistically significant differences favouring the proposed technique for all parameters except for the amount of keratinized tissue at 6 months.

CONCLUSIONS

The proposed test technique is more suitable for root coverage procedures with ADMG, and the new parameter evaluated appears valuable for root coverage analysis. (Clinicaltrials.gov Identifier: NCT01175720).

Acellular dermal matrices: Use in reconstructive and aesthetic breast surgery

Acellular dermal matrices (ADMs) were first described for use in breast surgery in 2001. Since this initial report, ADMs have become an increasingly common component of implant-based breast procedures. ADMs have shown promise for use in both aesthetic and reconstructive breast surgery; however, concerns about their use remain because of the significant costs associated with these products. The present article reviews the history of ADM use in breast surgery and the outcomes reported to date. Common techniques for placement of ADMs in aesthetic revisionary and breast reconstruction surgery are provided, and use in the setting of chest wall irradiation and capsular contracture is discussed. Finally, the authors comment on the cost implications of these products in the Canadian and American health care systems.

Split mouth de-epithelization techniques for gingival depigmentation: A case series and review of literature

Gingival melanin pigmentation occurs in all races of mankind. Although clinical melanin pigmentation does neither present itself as a medical problem nor a disease entity, it is a major esthetic concern for many people, especially Asians. Esthetic gingival depigmentation procedures can be performed in such patients with excellent results. This case series presents a split mouth de-epithelization procedure using popular surgical techniques such as scalpel, bur abrasion or electrosurgery. These techniques were successfully used to treat gingival hyperpigmentation. Although we found that electrosurgery increased the efficacy of our work, giving a cleaner and neater work field, it required a lot of precision. In contrast, scalpel de-epithelization was easy and technique-friendly, giving excellent results and patient satisfaction. However, the cases are being followed-up to study the factors affecting the rate and length of time required for repigmentation and to study the repigmentation patterns. This case series also reviews the advantages and disadvantages of various techniques available for depigmentation, and reiterates that the scalpel technique still serves as a gold standard for depigmentation.

Coverage of gingival recession defects using acellular dermal matrix allograft with or without beta-tricalcium phosphate

The aim of this study was to investigate the effect of beta-tricalcium phosphate (β-TCP) particles in combination with acellular dermal matrix (ADM) allograft in gingival recession. Experimental gingival recession defects were created in beagle dogs and randomly assigned to one of the following groups: ADM, ADM + β-TCP, or coronally positioned flap (CPF; control). Tissues were histologically examined at 4, 8, or 16 weeks following treatment. A greater thickness of gingiva was observed at the sites treated in both the ADM + β-TCP and ADM groups than in the CPF group. The ADM + β-TCP group showed a statistically significant increase in both new bone and cementum formations compared to the ADM group. The results suggest that the combination of β-TCP and ADM is more effective in promoting new bone and cementum formations than ADM graft alone.

In vitro evaluation of acellular dermal matrix as a three-dimensional scaffold for gingival fibroblasts seeding

BACKGROUND

Tissue engineering principles could improve the incorporation of acellular dermal matrix (ADM). The aim of this study is to verify if ADM is a suitable three-dimensional matrix for gingival fibroblasts and cancerous cells ingrowth, and also if cultured medium conditioned in ADM affect cellular behavior.

METHODS

Canine gingival fibroblasts (CGF), human gingival fibroblasts (HGF), and murine melanoma cell line (B16F10) were seeded on ADM for up to 14 days. The following parameters were assessed: morphology and distribution of CGF, HGF, and B16F10; CGF and HGF viability; and the effect of ADM conditioned medium (CM) on CGF viability.

RESULTS

Epifluorescence revealed that CGF were unevenly distributed on the ADM surface, showing no increase in cell number over the periods of study; HGF formed a monolayer on the ADM surface in a higher number at 14 days (P <0.05); B16F10 exhibited an increase in cell number within 7 days (P <0.05), and were mainly arranged in cell aggregates on the ADM, forming a continuous layer at 14 days. A higher percentage of cells on the ADM surface (P <0.05) compared to inside was observed for all cell types. 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) values indicated higher cell viability in samples cultured with HGF compared to CGF (P = 0.024). A significantly lower cell viability for CGF grown in CM compared to cells grown in non-CM was observed at 48 and 72 hours (P <0.05).

CONCLUSIONS

ADM is not suitable as a three-dimensional matrix for gingival fibroblasts ingrowth. Gingival fibroblasts and highly proliferative cells as B16F10 can only be superficially located on ADM, and CGF are negatively affected by culture medium conditioned in ADM, reducing its viability.

Clinical evaluation of a dermic allograft in procedures to increase attached gingiva width

The aim of this study was to clinically evaluate the use of alloderm to increase the width of attached gingiva. Nine patients were selected. The inclusion criteria were: attached gingiva smaller than 1 mm; Miller's class I and II gingival recession; patients able to attend control dental appointments; absence of periodontal pocket and endodontic treatment in the neighboring area where the acellular dermal graft would be placed. The clinical evaluation included: allograft shrinkage 7, 14, 21, 30, 60 and 90 days after surgery; width of attached gingiva at the end of the study; difference in color and mobility of allograft. Allograft shrinkage was calculated by comparing its area immediately after surgery to its areas in the other days. Five standardized photographs were taken, digitized and the allograft area was measured. Paired Student's t-test was used to compare the clinical data (alpha=0.05). The mean allograft shrinkage 90 days after surgery was 90.43% and the mean width was 1.27 mm. Difference in color was observed in only 1 subject and no allograft mobility was detected. The results showed a large shrinkage of allograft 90 days after its insertion, raising doubts as to its validity for increasing the width of attached gingiva.

Biocompatibility of acellular dermal matrix graft evaluated in culture of murine macrophages

The acellular dermal matrix allograft has been used as an alternative to autogenous palatal mucosal graft. The aim of this study was the evaluation of the biocompatibility of an acellular dermal matrix (AlloDerm®) in culture of macrophages. For hydrogen peroxidase determination we used the method of Pick & Kesari, and the Griess method for nitric oxide determination,. Statistical analysis showed no significant difference (p ≤ 0,05) in the release of nitric oxide and hydrogen peroxide by the macrophages exposed to acellular dermal matrix and the negative control. The results suggest that acellular dermal matrix did not activate the cell inflammatory response.

Clinical and histological evaluation of an acellular dermal matrix allograft in combination with the coronally advanced flap in the treatment of Miller class I recession defects: an experimental study in the mini-pig

OBJECTIVES

To study the wound healing of acellular dermal matrix (ADM) allografts when used together with coronally advanced flaps (CAF) in the treatment of localized gingival recessions in the mini-pig experimental model.

MATERIAL AND METHODS

Dehiscence defects 4 x 5 mm were surgically created in one buccal root surface in each quadrant of PI, II, or III in three mini-pigs. They were then treated with CAF and the interposition of either a connective tissue graft (CTG) or ADM. As the primary outcome, the histological interface between the ADM and the root surface was studied and was compared with CTG. As secondary outcomes, we assessed the amount and quality of the keratinized tissue and clinical outcomes in terms of root coverage and recession reduction.

RESULTS

At 3 months, the CTG group attained a mean 76% root coverage, versus 62% in the ADM group. The histological interface with the root surface was similar in both groups. The apical migration of the epithelium was 1.79+/-0.46 mm for the CTG and 1.21+/-0.35 mm for ADM. Newly formed cementum was observed with both treatments. New bone and a newly formed periodontal ligament were shown in five specimens in the ADM group and in three in the CTG group.

CONCLUSION

Both materials showed similar clinical and histological outcomes.

A comparative evaluation of immediate dental implant with autogenous versus synthetic guided bone regeneration

Immediate implant is a placement of the implant immediately into fresh extraction socket site after tooth extraction and is considered to be a predictable and acceptable procedure. The present work is designed to evaluate the periodontal condition after immediate implant placement and the success rate of implant with autogenous versus synthetic guided bone regeneration. Twenty adult male patients with an endodontic failure, tooth fracture decayed tooth (hopeless tooth) were included in this study. Patients were divided into 2 groups: One group (I) received immediate implants augmented with autogenous bone graft, and the other (group II) received immediate implants augmented with a synthetic bone graft. The results revealed that there was a significant difference between the groups for pocket depth and clinical attachment level. The difference between the groups was statistically highly significant only at 12 months (P < .01). In addition, there was statistically significant difference between the groups at 9 and 12 months (P < .001). Moreover, there was significant decrease of marginal bone loss in group I compared with group II (P < .01). In addition, there was statistically significant difference between the both groups at 9 and 12 months for bone density (P < .001). Moreover, there was significant decrease of marginal bone loss in group I compared with group II (P < .01). In conclusion, the immediate dental implant placement with autogenous bone graft showed a significant superiority to synthetic bone graft. In addition, the immediate placement-delayed loaded dental implant remains the procedure of choice for predictable achieving of osseointegration.

A patient-centered clinical evaluation of acellular dermal matrix graft in the treatment of gingival recession defects

BACKGROUND

The present randomized controlled trial was conducted to evaluate acellular dermal matrix (ADM) graft in terms of patient satisfaction and its effectiveness and efficiency in the treatment of gingival recession.

METHODS

Fourteen patients (seven males and seven females) with Miller Class I and II recessions > or =3 mm participated in this 6-month clinical study. They were assigned randomly to the ADM group (ADM graft and coronally positioned flap [CPF]) or the CPF group (CPF alone). Results were evaluated based on parameters measuring patient satisfaction and clinical outcomes associated with the two treatment procedures. Significance was set at P <0.05.

RESULTS

The mean recession was 4.0 +/- 1.0 mm and 3.7 +/- 0.7 mm for the ADM and CPF groups, respectively. For the ADM group, the defect coverage was 3.85 +/- 0.89 mm or 97.14% compared to the CPF group, in which the defect coverage was 2.85 +/- 0.89 mm or 77.42%. The difference between the two groups was statistically significant (P <0.05). There were no statistically significant differences between the two groups in the remaining clinical parameters and overall patient satisfaction except in criteria related to patient comfort and cost effectiveness, in which CPF alone produced significantly better results (P <0.03).

CONCLUSIONS

ADM graft is significantly superior with regard to effectiveness and efficiency in the treatment of gingival recession than CPF alone. CPF emerges as a better option than ADM graft in terms of cost effectiveness and patient comfort.

Ridge Expansion With Acellular Dermal Matrix and Deproteinized Bovine Bone: A Case Report

Reduction of the original height and width of the alveolar bone of an edentulous site precludes optimal positioning of implant fixtures and may esthetically compromise the prosthesis. Ridge expansion at the time of extraction can prevent the need for ridge reduction and reduces the number of surgical interventions.A patient with a narrow ridge with buccal deformity was treated for the staged placement of an implant. The tooth was extracted. The socket was expanded with an osteotome and an acellular dermal matrix graft was applied as a barrier membrane. The underlying bone showed good healing with maturity and the acellular dermal matrix had the potential to increase the keratinized tissue in the extraction area.

Comparison of Two Surgical Procedures for Use of the Acellular Dermal Matrix Graft in the Treatment of Gingival Recessions: A Randomized Controlled Clinical Study

BACKGROUND

The aim of this randomized, controlled, clinical investigation was to compare two surgical techniques for root coverage with the acellular dermal matrix graft to evaluate which technique provided better root coverage, a better esthetic result, and less postoperative discomfort.

METHODS

Fifteen patients with bilateral Miller Class I or II gingival recessions were selected. Fifteen pairs of recessions were treated and assigned randomly to the test group, and the contralateral recessions were assigned to the control group. The control group was treated with a broader flap and vertical releasing incisions; the test group was treated with the proposed surgical technique, without vertical releasing incisions. The clinical parameters evaluated were probing depth, relative clinical attachment level, gingival recession (GR), width of keratinized tissue, thickness of keratinized tissue, esthetic result, and pain evaluation. The measurements were taken before the surgeries and after 6 months.

RESULTS

At baseline, all parameters were similar for both groups. At 6 months, a statistically significant greater reduction in GR favored the control group. The percentage of root coverage was 68.98% and 84.81% for the test and control groups, respectively. The esthetic result was equivalent between the groups, and all patients tolerated both procedures well.

CONCLUSIONS

Both techniques provided significant root coverage, good esthetic results, and similar levels of postoperative discomfort. However, the control technique had statistically significantly better results for root coverage of localized gingival recessions.

A Comparative Study of Root Coverage Using Acellular Dermal Matrix With and Without Enamel Matrix Derivative

BACKGROUND

The aim of this study was to compare root coverage using acellular dermal matrix (ADM) with and without enamel matrix derivative (EMD) on the percentage of root coverage, probing attachment level, and the amount of keratinized tissue in the treatment of localized recession.

METHODS

Eighty-two contralateral sites in 14 patients with >or=2 mm of Miller Class I or III buccal tissue recession were treated. Forty-one test sites were treated with coronally advanced flap (CAF) using ADM in conjunction with EMD, whereas 41 control sites were treated with CAF using ADM alone. A split-mouth design was used for this study with 82 sites. Patients were followed for 3 and 6 months. A paired t test was conducted with the subject as the unit of analysis.

RESULTS

Based on paired t tests, both groups had significant improvement in the percentage of root coverage, probing attachment levels, and increased keratinized tissue. Only keratinized tissue in the test group demonstrated a statistically significant greater increase compared to controls at the 6-month evaluation (P = 0.006).

CONCLUSION

The use of EMD in conjunction with ADM resulted in a statistically significant effect on keratinized tissue increase, but no significant effects on probing attachment level or percentage of root surface coverage.

Effect of In Vitro Gingival Fibroblast Seeding on the In Vivo Incorporation of Acellular Dermal Matrix Allografts in Dogs

BACKGROUND

Acellular dermal matrix allograft (ADMA) has been used in various periodontal procedures with successful results. Because ADMA has no blood vessels or cells, slower healing and incorporation are observed compared to a subepithelial connective tissue graft. Fibroblasts accelerate the healing process by regulation of matrix deposition and synthesis of a variety of growth factors. Thus, the objective of this study was to evaluate histologically if gingival fibroblasts affect healing and incorporation of ADMA in dogs when used as a subepithelial allograft.

METHODS

Gingival fibroblasts were established from explant culture from the connective tissue of keratinized gingiva collected from the maxilla of seven mongrel dogs. ADMA was seeded with gingival fibroblasts and transferred to dogs. Surgery was performed bilaterally, and the regions were divided into two groups: ADMA+F (ADMA containing fibroblasts) and ADMA (ADMA only). Biopsies were performed after 2, 4, and 8 weeks of healing.

RESULTS

The quantity of blood vessels was significantly higher in the ADMA+F group at 2 weeks of healing (Kruskal-Wallis; P <0.05). There was no statistical difference (P >0.05) in the number of cell layers, epithelial area, or inflammatory infiltrate between the two groups at any stage of healing.

CONCLUSION

The enhanced vascularization in vivo in early stages supports the important role of fibroblasts in improving graft performance and wound healing of cultured graft substitutes.

A two-year prospective study of coronally positioned flap with or without acellular dermal matrix graft

AIM

Evaluation of the treatment of gingival recessions with coronally positioned flap with or without acellular dermal matrix allograft (ADM) after a period of 24 months.

METHODS

Thirteen patients with bilateral gingival recessions were included. The defects were randomly assigned to one of the treatments: coronally positioned flap plus ADM or coronally positioned flap alone. The clinical measurements were taken before the surgeries and after 6, 12 and 24 months.

RESULTS

At baseline, the mean values for recession height were 3.46 and 3.58 mm for the defects treated with and without the graft, respectively (p>0.05). No significant differences between the groups were observed after 6 and 12 months in this parameter. However, after 24 months, the group treated with coronally positioned flap alone showed a greater recession height when compared with the group treated with ADM (1.62 and 1.15 mm, respectively--p<0.05). A significant increase in the thickness of keratinized tissue was observed in the group treated with ADM as compared with coronally positioned flap alone (p<0.05).

CONCLUSIONS

ADM may reduce the residual gingival recession observed after 24 months in defects treated with coronally positioned flap. In addition, a greater gingival thickness may be achieved when the graft is used.

Evaluation of the Efficacy of the Acellular Dermal Matrix Allograft with Partial Thickness Flap in the Elimination of Gingival Melanin Pigmentation. A Comparative Clinical Study with 12 Months of Follow-Up

Acellular dermal matrix (ADM) has been used as a substitute for gingival allografts. The aim of this study was to evaluate the effectiveness of ADM with partial thickness flap in the elimination of gingival melanic pigmentations. Fifteen patients presenting bilateral gingival melanin pigmentation were selected for this study. Each side of the pigmentation was randomly assigned to be part of a group. The sites of the experimental group had a partial thickness flap raised, excised, followed by adaptation and suture of the ADM. On the opposite side (ie, sites from the control group), the oral epithelium was removed with a diamond bur. The healing process was evaluated at 1 and 2 weeks, and 1, 3, 6, 9, and 12 months postoperatively. Images of the patient's follow-up were digitalized, and occurrence and quantification of clinical repigmentation were evaluated. After 12 months, minimal repigmentation (mean 3.14 +/- 7.45%) was noted in 8 of 15 sites from the ADM group, while significant repigmentation (mean 55.84 +/- 27.25%) was seen in 15 of 15 abrasion sites. According to our results, it can be concluded that ADM may be successfully used in the elimination or greater reduction of gingival melanic pigmentations, and is more efficient than epithelium abrasion after 12 months (p < 0.0001).

CLINICAL SIGNIFICANCE

Gingival pigmentation is a common finding in several ethnic groups. Although physiologic melanin pigmentation is not a medical problem, cosmetic demands may turn it into a problem of social acceptance in different cultures. In this way, different treatment modalities have been used with the aim of removing pigmentations for esthetic reasons. In the present study, the use of ADM with partial thickness flap resulted in more effective elimination of gingival melanin pigmentation, as repigmentation occurred later and was much weaker when compared to the outcomes of epithelial abrasion.

Acellular dermal matrix for mucogingival surgery: a meta-analysis

BACKGROUND

Many clinical studies revealed the effectiveness of acellular dermal matrix (ADM) in the treatment of mucogingival defects. The purpose of this meta-analysis was to compare the efficacy of ADM-based root coverage (RC) and ADM-based increase in keratinized tissues to other commonly used mucogingival surgeries.

METHODS

Meta-analysis was limited to randomized clinical trials (RCT). Articles from January 1, 1990 to October 2004 related to ADM were searched utilizing the MEDLINE database from the National Library of Medicine, the Cochrane Oral Health Group Specialized Trials Registry, and through hand searches of reviews and recent journals. Relevant studies were identified, ranked independently, and mean data from each were weighted accordingly. Selected outcomes were analyzed using a meta-analysis software program. The significant estimates of the treatment effects from different trials were assessed by means of Cochrane's test of heterogeneity.

RESULTS

1) Few RCT studies were found to compile the data. In summary, selection identified eight RCT that met the inclusion criteria. There were four studies comparing ADM versus a connective tissue graft for root coverage procedures, two studies comparing ADM versus coronally advanced flap (CAF) for root coverage procedures, and two studies comparing ADM to free gingival graft in augmentation of keratinized tissue. 2) There were no statistically significant differences between groups for any of the outcomes measured (recession coverage, keratinized tissue formation, probing depths, and clinical attachment levels). 3) The majority of the analyses demonstrated moderate to high levels of heterogeneity. 4) Considering the heterogeneity values found among the studies, certain trends could be found: a) three out of four studies favored the ADM-RC group for recession coverage; b) a connective tissue graft tended to increase keratinized tissue compared to ADM (0.52-mm difference; P = 0.11); c) there were trends of increased clinical attachment gains comparing ADM to CAF procedures (0.56-mm difference; P = 0.16).

CONCLUSIONS

Differences in study design and lack of data precluded an adequate and complete pooling of data for a more comprehensive analysis. Therefore, considering the trends presented in this study, there is a need for further randomized clinical studies of ADM procedures in comparison to common mucogingival surgical procedures to confirm our findings. It is difficult to draw anything other than tentative conclusions from this meta-analysis of ADM for mucogingival surgery, primarily because of the weakness in the design and reporting of existing trials.

Evaluation of osteogenic and chondrogenic activities of prefabricated periallografts

Reconstruction of cartilage and bone defects has always been a challenging problem for the surgeon. Basic elements that are responsible for the repair process of these tissues are periost and perichondrium. Although several methods for the use of periost and perichondrium are proposed in the literature, the osteogenic and chondrogenic capacities of these tissues were shown to be the most important factor for a successful outcome. Bone and cartilage formation in acellular dermal matrix (ADM) prefabricated with periost and perichondrium was studied in 20 New Zealand rabbits. Morphologic and histologic evaluation and comparison of the newly formed tissues were evaluated. Four rabbits were excluded from the study because of infection, and specimens were obtained at 4, 6, 8, and 12 weeks after the study began from the remaining 16 rabbits. A gradual increase in bone and cartilage tissue formation through the 4th to 12th weeks was documented by reason of perichondrium and periost activation infiltrating into acellular dermal allografts. In view of the data obtained, it was concluded that periost or perichondrium prefabricated over ADM may be an alternative technique of cartilage and bone formation that may provide adequate tissue with elastic and osteo- and chondroconductive properties for the reconstruction of challenging defects.

Oral reconstructive and corrective considerations in periodontal therapy

This paper was prepared by the Research, Science and Therapy Committee of the American Academy of Periodontology. It is intended to provide information for the dental profession and other interested parties. The purpose of this paper is to provide a general overview of oral reconstructive and corrective procedures used in periodontal therapy. It is not intended to be a comprehensive review of this subject.

Management of Gingival Recession by the Use of an Acellular Dermal Graft Material: A 12-Case Series

BACKGROUND

Different soft tissue defects can be treated by a variety of surgical procedures. Most of these techniques require the palatal area as a donor site. Recently, an acellular dermal graft has become available that can substitute for palatal donor tissue.

METHODS

This study describes the surgical technique for gingival augmentation and root coverage and the results of 12 clinical cases. A comparison between the three most popular mucogingival procedures for root coverage is also presented.

RESULTS

The results of the 12 patients and the 26 denuded surfaces have shown that we can obtain a mean root coverage of 74% with the acellular dermal graft. Thirteen out of the 26 denuded surfaces had complete root coverage. The average increase in keratinized tissue was 1.19 mm. It seems that the long-term results of the cases are stable.

CONCLUSION

The proposed technique of root coverage with an acellular dermal graft can be a good alternative to soft tissue grafts for root coverage, and it should be part of our periodontal plastic surgery armamentarium.