Coronally positioned flap with or without acellular dermal matrix graft in the treatment of Class I gingival recessions: a randomized controlled clinical study

BACKGROUND: The aim of this study was to clinically evaluate the treatment of Class I gingival recessions by coronally positioned flap with or without acellular dermal matrix allograft (ADM). METHODS: Thirteen patients with comparable bilateral Miller Class I gingival recessions (> or = 3.0 mm) were selected. The defects were randomly assigned to one of the treatments: coronally positioned flap and acellular dermal matrix (ADM group) or coronally positioned flap alone (CPF group). The clinical parameters included: probing depth (PD), clinical attachment level (CAL), recession height (RH), recession width (RW), height of keratinized tissue (HKT), thickness of keratinized tissue (TKT), plaque index (PI), and gingival index (GI). The measurements were taken before the surgeries and after 6 months. RESULTS: The mean baseline recession was 3.4 mm and 3.5 mm for ADM group and CPF group, respectively. After 6 months, both treatments resulted in significant root coverage (P < 0.01), reaching an average of 2.6 mm (76%) in the ADM group and 2.5 mm (71%) in the CPF group. The difference in recession reduction between treatments was not statistically significant. There were no statistically significant differences between the treatments in PD, CAL, RH, RW, and HKT. However, the mean TKT gain was 0.7 mm for the ADM group and 0.2 mm for the CPF group (P < 0.01). CONCLUSION: It can be concluded that both techniques could provide significant root coverage in Class I gingival recessions; however, a greater keratinized tissue thickness can be expected with ADM.     

An 18-year longitudinal study of untreated mucogingival defects.

BACKGROUND: A study was conducted to observe the changes in areas with untreated mucogingival defects over an 18-year period. The results in this group after 4 and 10 years were previously published. METHODS: Upon entering dental school, a group of 39 freshman dental students were assessed for plaque index, gingival index, probing depth, and width of keratinized tissue. At that time, 112 sites of inadequate keratinized gingiva were found. Seventeen of the original 39 participants with a total of 61 sites were reassessed for the same parameters after 18 years. RESULTS: The results revealed that 19 sites showed a slight increase in keratinized tissue, 35 were unchanged (for a total of 54 stable sites), and 7 sites showed a slight decrease in keratinized tissue. The mean width of keratinized tissue at the beginning of the study was 1.74+/-0.545 mm and 2.02+/-0.885 mm after 18 years. This represented a small, but statistically significant increase in the width. The plaque index (PI) and gingival index (GI) of this group at baseline (PI = 0.77+/-0.439 and GI = 0.93+/-0.447) and at 18 years (PI = 0.36+/-0.344 and GI = 0.65+/-0.303) indicated a high level of oral hygiene and gingival health. CONCLUSIONS: It was concluded that in the absence of gingival inflammation, areas with small amounts of keratinized tissue may remain stable over long periods of time.     

Free gingival graft and acellular dermal matrix for gingival augmentation: a 15-year clinical study

This study evaluated clinical outcomes of acellular dermal matrix (ADM) allograft compared with autogenous free gingival graft (FGG) for gingival augmentat     

Comparison of acellular dermal graft and palatal autograft in the reconstruction of keratinized gingiva around dental implants: a case report

The use of autogenous gingival grafts has proved to be an effective and predictable way to increase the amount of keratinized gingiva. However, discomfort and pain at the donor site are unavoidable. Acellular dermal matrix (ADM) allograft can be used as a donor tissue to eliminate the need for another surgical site and alleviate pain and trauma. The purpose of this study was to evaluate the effectiveness of ADM allograft in increasing the width of keratinized gingiva around dental implants. A patient with inadequate keratinized gingiva around dental implants in maxillary and mandibular anterior regions received either an ADM graft or palatal autograft by random allocation. The width of keratinized gingiva and other clinical periodontal parameters were recorded initially and at 3 and 6 months after surgery. Both grafts provided satisfactory results. The width of keratinized tissues was increased by using the ADM allograft, but by a lesser amount than seen with the autogenous gingival graft.     

Acellular dermal matrix allografts to achieve increased attached gingiva. Part 2. A histological comparative study

BACKGROUND: In part 1 of this study, we compared the clinical efficacy of freeze-dried acellular dermal matrix (ADM) allograft in 6 patients with autogenous free gingival graft (FGG) in 6 patients for increasing the width of attached gingiva in the mandibular anterior area. The purpose of the present study was to histologically compare the microstructure of ADM and FGG treated sites from the same group. METHODS: Biopsies were harvested from all 12 patients at 6 months postsurgery. The biopsies included the grafted sites with adjacent alveolar mucosa and gingiva propria and also donor palatal mucosa saved at the time of surgery. The 5 microm thick, neutral buffered formalin fixed, paraffin-embedded tissue sections were stained with hematoxylin and eosin (H&E), Masson's trichrome, and Verhoeff-van Gieson stains in order to investigate the density of collagen and elastic fibers. Additional sections were stained with periodic acid-Schiff (PAS) and Papanicolaou's stain to identify the presence of glycogen granules in the epithelial layer and to highlight the keratin layer respectively. RESULTS: The unique appearance of ADM-derived tissue did not parallel any known oral mucosa. The connective tissue portion contained dense to extremely dense collagen fibers along with scattered elastic fibers. The demarcations between the ADM graft and the coronal gingiva as well as the apical alveolar mucosa were usually not very defined. A moderate to thin epithelial layer, with heterogeneous expression of keratinization and flat epithelium-connective tissue interface, covered the lamina propria. Both the thickness of the epithelium and the degree of keratinization decreased in apical direction, being mostly para- or orthokeratinized in the area close to gingiva and non-keratinized adjacent to the alveolar mucosa. In the FGG-treated sites, the density of collagen fibers was less than in ADM-derived tissue, palatal mucosa, and gingiva. Elastic fibers were very sparse, comparable to gingiva, but much less than in ADM-derived tissue. The epithelium was moderate, somewhat thinner but the shape of the rete ridges resembled that of palatal mucosa. Similar to gingiva epithelium, the epithelium of the FGG-treated area was relatively uniform in both thickness and keratinization, mostly para-keratinized with a well defined border to the non-keratinized alveolar mucosa. Underneath the FGG-alveolar mucosa junction, a scar band composed of extremely dense collagen fibers consistently existed. CONCLUSIONS: The results of this 6-month histological evaluation suggest that: 1) the resultant tissue types of ADM grafts were similar to "scar" tissue; 2) the non-vital dermal matrix of ADM allograft lacked the capability of directing cyto-differentiation of the covering epithelium; 3) autogenous FGG-derived tissue was neither identical to donor palatal mucosa nor to adjacent gingiva propria; 4) the connective tissue of donor palatal mucosa only partially contributed to the differentiation of the epithelium covering the FGG-treated area; and 5) the epithelium/connective tissue microenvironment surrounding the recipient site influenced the epithelial differentiation of the graft; this may play a more critical role in ADM grafting than in the grafting of autogenous FGG.     

Subpedicle acellular dermal matrix graft and autogenous connective tissue graft in the treatment of gingival recessions: a comparative 1-year clinical study

BACKGROUND: Many surgical techniques have been proposed for the correction of dental root exposition. Among these, bilaminar techniques (BTs) have been reported as offering the best results in terms of root coverage (RC). However, BTs require a second surgical site to harvest the graft, with discomfort for the patient. The use of an acellular dermal matrix (ADM) avoids the need for a donor site. The aim of this study was to compare the clinical results of 2 BTs by autogenous connective tissue (CT) or ADM. METHODS: In 30 systemically healthy, non-smoking patients aged 34.5 +/- 5.2 years, who showed no periodontal pockets >4 mm after a hygienic phase, a Miller's class I or II gingival recession was treated for root coverage. All patients underwent a BT: in 15 patients, an autogenous connective tissue graft was employed (CT group); in the other 15 subjects, ADM was used as a subepithelial graft (ADM group). Prior to and 1 year after surgical treatment, the following clinical parameters were recorded: gingival recession (GR), probing depth (PD), clinical attachment level (CAL), width of keratinized tissue (KT), and gingival thickness (GT); the percentage of RC (%RC) was also calculated, and the data were statistically analyzed. The number of weeks needed to obtain complete healing with mature tissue appearance was also recorded. RESULTS: Both groups yielded significant improvements in terms of GR decrease, CAL and KT gain, and GT increase as compared to baseline values. The mean %RCs were 88.80 +/- 11.65% and 83.33 +/- 11.40% in the CT and ADM groups, respectively. Complete RC was observed in 46.6% of patients from the CT group, and 26.6% of the ADM group patients. No significant differences were observed between the two techniques for GR, CAL, and GT improvements; however, the CT group produced a significantly (P <0.01) greater increase in KT as compared to the ADM group. Complete healing of the surgical procedure was observed 6.20 +/- 1.01 and 8.93 +/- 1.33 weeks after suture removal in the CT and ADM groups, respectively (P <0.001). CONCLUSIONS: The CT and ADM subepithelial grafts were similarly able to successfully treat gingival recession defects; however, the CT group obtained a significantly greater increase in KT, and showed a quicker complete healing.     

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

Root coverage procedures using subgingival soft tissue grafts or guided tissue regeneration have attracted much interest within the past 2 decades. Recently, acellular dermal matrix allograft (ADMA) has been introduced as a substitute for palatal donor tissue in gingival augmentation procedures. This study was undertaken to examine the potential of ADMA to be used as a substitute for autogenous connective tissue graft material in a root coverage procedure in a case with moderate gingival recession combined with reduced keratinized attached gingiva. After thorough root planing and conditioning of the root surface with a saturated solution of tetracycline-HCl, a trapezoidal mucoperiosteal flap was raised and the papillae were de-epithelialized. The exposed bone surrounding the exposed root surface was perforated with a No. 2 round drill, and the exposed root and surrounding bone were covered by ADMA. The allograft was stabilized by 5-0 vicryl sutures. The flap was coronally positioned to completely cover the ADMA. Healing was uneventful. Eight-month observations and measurements showed root coverage of more than 3.5 mm (>80%), a gingival margin that was harmonious with the neighboring teeth, and an increase of the zone of keratinized attached gingiva, from 1 to 3 mm. Within the limitations of these clinical observations, it is suggested that ADMA may be a possible substitute to free autogenous connective tissue grafts and/or bioabsorbable barrier membranes. Further clinical and histological studies are necessary to understand the healing process of this surgical wound.     

Comparison of 2 techniques of subepithelial connective tissue graft in the treatment of gingival recessions.

BACKGROUND: The clinical outcome of connective tissue grafts in the treatment of gingival recessions has been documented in numerous studies. However, no attempt has been made to correlate the postoperative mucogingival changes with the surgical parameters. The present retrospective clinical study was undertaken to 1) evaluate root coverage and mucogingival changes 1 to 1.5 years following treatment of Miller's Class I and II recession defects using 2 variants of the subepithelial connective tissue graft (SCTG) procedure, and 2) assess the effect of the surgical parameters on the postoperative gingival width. METHODS: Thirty-one recessions in 10 patients treated with the envelope technique (E) and 31 recessions in 11 patients treated with coronally positioned flap combined with connective tissue graft (CP) were retrospectively analyzed to evaluate: 1) percentage of root coverage obtained with the 2 procedures and variations in width of keratinized tissue (KT) 1 to 1.5 years postsurgery, and 2) the effect of the surgical parameters on the postoperative gingival width. RESULTS: Results showed a mean root coverage percentage of 89.6 +/- 15% for the E group and 94.7 +/- 11.4% for the CP group; the difference between groups was statistically insignificant (P = 0.1388). Mean KT increased significantly from 1.4 +/- 1.1 mm presurgery to 4.5 +/- 1.1 mm postsurgery for the E group while a minor increase in KT was observed in the CP group (2 +/- 1.5 mm presurgery versus 2.7 +/- 1.6 mm postsurgery). For both treatment groups, the mean postsurgical width of keratinized tissue (POSTKT) was found to be mathematically correlated with the mean presurgical width of keratinized tissue (PREKT) and the corono-apical height of the graft that remained exposed (GE) coronal to the flap margin in the recipient site. CONCLUSIONS: Treatment of human gingival recession defects by the 2 variants of SCTG resulted in significant recession reduction. When SCTG is grafted beneath alveolar mucosa using the combined technique (CP), transformation of the mucosa into keratinized tissue does not seem to occur, at least within 1 to 1.5 years postsurgery. The treatment outcome in terms of keratinized tissue width seems to be correlated with the presurgical gingival dimensions and the height of the graft that remains exposed at the end of the surgical procedure.     

Treatment of gingival recession in two surgical stages: Free gingival graft and connective tissue grafting

This report describes a clinical case of severe Miller Class II gingival recession treated by two stages of surgery that combined a free gingival graft and connective tissue grafting. First, a free gingival graft (FGG) was performed to obtain an adequate keratinized tissue level. Three months later, a connective tissue graft (CTG) was performed to obtain root coverage. The results indicated that the FGG allows for a gain in the keratinized tissue level and the CTG allows for root coverage with decreased recession level after 16 months. Therefore, for this type of specific gingival recession, the combination of FGG and CTG can be used.     

下颌后牙区不同时机游离龈移植的效果对比

目的对不同时机的游离龈移植术（FGG）增加下颌后牙区种植体周颊侧角化龈的临床效果进行评价。 方法选择2018年10月至2020年10月就诊于东莞健力口腔医院修复种植科下颌后牙区单牙缺失角化牙龈不足的患者（宽度为2 ~ 4 mm）共40例,将纳入的40例患者进行编号,以随机数字表法抽取20例为实验组,其余20例为对照组。实验组种植Ⅰ期手术时放置愈合基台同期行FGG。对照组种植Ⅰ期手术潜入式愈合,3个月Ⅱ期手术时放置愈合基台同期行FGG。术后观察移植物的存活情况,测量术前牙槽嵴顶剩余角化龈宽度,测量颊侧FGG后即刻、移植术后2个月、戴牙后即刻和戴牙后6个月的颊侧角化龈宽度,使用SPSS 20.0软件对移植物存活率、颊侧不同时间点角化龈宽度等进行统计分析,采用配对t检验进行比较,以P<0.05认为差异有统计学意义。 结果两组手术均获得成功,伤口正常愈合,组织瓣均存活。术前实验组和对照组牙槽嵴顶余留角化龈宽度分别为（2.9 ± 0.3）和（3.0 ± 0.3）mm,差异无统计学意义。实验组和对照组术后即刻种植体颊侧龈缘中点角化龈宽度分别为（4.9 ± 0.5）和（4.9 ± 0.5）mm,差异无统计学意义（t = 0.2,P = 0.8）。实验组和对照组术后2个月颊侧龈缘中点角化龈宽度分别为（4.2 ± 0.4）和（4.5 ± 0.4）mm,差异有统计学意义（t = -2.9,P<0.05）。实验组和对照组戴牙当天种植体颊侧龈缘中点角化龈宽度为（3.2± 0.4）和（3.7± 0.5）mm,差异有统计学意义（t = -2.6,P<0.05）。实验组和对照组戴牙后6个月种植体颊侧龈缘中点角化龈宽度为（3.1 ± 0.4）和（3.5 ± 0.3）mm,差异有统计学意义（t = -3.7,P<0.05）。 结论当下颌后牙区剩余角化龈为2 ~ 4 mm时,FGG在种植Ⅰ期手术同期及Ⅱ期手术同期均能获得较好的增加角化龈的效果。相比于种植Ⅰ期手术同期进行FGG,Ⅱ期手术同期FGG能获得更好的颊侧角化龈的宽度,但会增加手术次数。     

Clinical evaluation of 3 techniques to augment keratinized tissue without root coverage

BACKGROUND: The importance of keratinized tissue is a controversial subject. However, in some situations most clinicians would agree that surgical procedures to increase the amount of keratinized tissue without root coverage are indicated. In this study, 3 surgical procedures were compared in their ability to increase the width of keratinized tissue. They are: the epithelized autogenous masticatory mucosa graft (free gingival graft), autogenous predominately connective tissue graft (connective tissue graft), and acellular dermal matrix. METHODS: Forty-five patients referred for treatment of areas with inadequate keratinized tissue were randomly assigned into 1 of 3 groups of 15 each. Each group was treated with 1 of the 3 surgical procedures to increase the width of keratinized tissue. The width of keratinized tissue pre- and postsurgery was evaluated. RESULTS: All 3 groups started with a similar width of keratinized tissue. All of the surgical procedures resulted in a statistically significant increase in the width of keratinized tissue: free gingival graft, 4.1 mm; connective tissue graft, 3.6 mm; and acellular dermal matrix, 4.1 mm. CONCLUSION: A statistically significant increase in the amount of keratinized tissue was obtained with all 3 surgical procedures evaluated.     

Randomized,Controlled Clinical Trial to Evaluate a Xenogeneic Collagen Matrix as an Alternative to Free Gingival Grafting for Oral Soft Tissue Augmentation

Background : The standard of care for increasing keratinized tissue (KT) and vestibular area is an autogenous free gingival graft (FGG) and vestibuloplasty; however, there is morbidity associated with the harvest of autogenous tissue, and supply is limited. The purpose of this study is to determine if a xenogeneic collagen matrix (CM) might be as effective as FGG. Methods: This study is a single‐masked, randomized, controlled, split‐mouth study of 30 patients with insufficient zones of KT (<2 mm). It uses a within‐patient treatment‐comparison design to establish non‐inferiority of the test (CM) versus control (FGG) therapy. The primary efficacy endpoint was change in KT width (?KT) from surgery to 6 months post‐surgery. Secondary endpoints included traditional periodontal measures, such as clinical attachment level, recession, and bleeding on probing. Patient‐reported pain, discomfort, and esthetic satisfaction were also recorded. Biopsies were obtained at 6 months. Results: Surgery and postoperative sequelae were uneventful, with normal healing observed at both test and control sites. The primary outcome, ?KT width at 6 months, did not establish non‐inferiority of CM compared to FGG (P = 0.9992), with the FGG sites averaging 1.5 mm more KT width than CM sites. However, the amount of new KT generated for both therapies averaged ≥2 mm. Secondary outcomes were not significantly different between test and control sites. All site biopsies appeared as normal mucoperiosteum with keratinized epithelium. CM sites achieved better texture and color matches, and more than two‐thirds of patients preferred the appearance of their CM sites. Conclusion: With the proviso of sufficient KT (≈2 mm in width) and study goals of lower morbidity, unlimited supply, and patient satisfaction, CM appears to be a suitable substitute for FGG in vestibuloplasty procedures designed to increase KT around teeth.     

A pilot study to evaluate a tissue-engineered bilayered cell therapy as an alternative to tissue from the palate

BACKGROUND: This study evaluated the safety and effectiveness of a tissue-engineered skin product composed of viable neonatal keratinocytes and fibroblasts and compared it to a free gingival graft (FGG) in a procedure to enhance keratinized tissue (KT) and wound healing around teeth that do not require root coverage. METHODS: Twenty-five subjects were enrolled who had at least two non-adjacent teeth in contralateral quadrants exhibiting an insufficient zone of attached gingiva requiring soft tissue grafting where root coverage was not desired. One tooth was randomized to receive an FGG, and the other was randomized to receive bilayered cell therapy (BCT). The amount of KT was measured at baseline and 3 and 6 months, and the texture and color of the grafted tissue were compared to the surrounding tissue at months 1, 3, and 6. A questionnaire was used to determine subject preference at 6 months. Biopsies and persistence studies were performed on a subset of the subjects. RESULTS: The FGG generated statistically significantly (P <0.001) more KT than the test device (BCT) (4.5 +/- 0.80 mm versus 2.4 +/- 1.02 mm); no significant difference in recession or clinical attachment level was detected between treatment groups (P = 0.212 and P = 0.448, respectively); and no significant differences were detected at any time point for bleeding on probing (BOP), resistance to muscle pull, or inflammation. The BCT group had significantly better color and texture match with surrounding tissue (P <0.001), and subject preference was significantly greater for the BCT group (P = 0.041). No device-related adverse events or safety issues occurred during the course of the study. CONCLUSIONS: The tissue-engineered graft BCT was safe and capable of generating de novo KT without the morbidity and potential clinical difficulties associated with donor-site surgery. The amount of KT generated with FGG was greater than generated with BCT; however, 24 of 25 test sites demonstrated an increase in KT at 6 months, with more than three-quarters of the sites yielding > or =2 mm bands of KT.     

Is there any biomaterial substitute for peri-implant soft tissue phenotype modification? A network meta-analysis of the appraisal literature

Evidence shows that an increased width and thickness of the keratinized mucosa favours peri-implant health. The aim of this network meta-analysis was to compare the clinical effects of alternative biomaterials for peri-implant soft tissue phenotype modification (PSPM) in patients with dental implants when compared to autologous tissue grafts. An electronic search without language or date limitations was performed in four databases and the grey literature for articles published until November 2020. The eligibility criteria included randomized clinical trials (RCTs) evaluating the clinical outcomes of biomaterials for PSPM. A pairwise and network meta-analysis was conducted for each parameter to assess and compare the outcomes between the different treatment arms for the primary and secondary outcomes. A total of 11 RCTs were included in this review. The free gingival graft (FGG) showed the best clinical effect for increasing keratinized mucosa width (KMW). When compared in a network, the FGG demonstrated the best treatment ranking of probability results, followed by connective tissue graft (CTG), acellular dermal matrix (ADM), and xenogeneic collagen matrix (XCM). For the parameters ‘mucosa thickness’ and ‘participant satisfaction with aesthetics’, the results were CTG > ADM > XCM and XCM > ADM > CTG, respectively. Autogenous tissue grafts (FGG/CTG) demonstrate the best results in increasing KMW and mucosa thickness when compared to the other biomaterials.     

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.     

Creeping attachment: autogenous graft vs dermal matrix allograft

For many years, free autogenous grafts have been used as a method of gaining keratinized tissue around teeth with mucogingival problems. Creeping attachment using autogenous graft material has been actively studied. In addition, biocompatible, acellular connective-tissue material has recently been used as an alternative to free gingival grafts to increase the zone of keratinization. This report presents a patient with bilateral mucogingival defects in the canine and premolar areas. The patient received an autogenous graft on one side and a dermal matrix allograft on the contralateral side. Creeping attachments were measured and compared at 3 months and 12 months after surgery. After 12 months of healing, an average of 1.23 mm of creeping attachment was measured on the free gingival graft side and 0.96 mm of creeping attachment was measured with the dermal matrix allograft.     

Comparative clinical evaluation of freeze-dried skin allografts and autogenous gingival grafts in humans.

Freeze-dried skin (FDS) allografts and fresh autogenous free gingival grafts (FGG) were placed in five paired sites in four patients. Both types of grafts healed uneventfully. Evaluation over a 1-year period demonstrated no statistically or clinically significant differences between the FDS and FGG when: a) increase in the width of keratinized gingiva, b) decrease in recession, c) decrease in sulcus depth, k) gain in attachment level, or e) percent shrinkage of the graft were compared. It was concluded that FDS performs essentially similar to FGG in the correction of mucogingival problems, and has the advantages of decreased patient morbidity (no donor site) and availability of abundant amounts of graft material when needed.     

Clinical efficacy of acellular dermal matrix for plastic periodontal and implant surgery: a systematic review

This review was performed to validate the clinical efficacy of acellular dermal matrix (ADM) for plastic periodontal and implant surgery. Four electronic databases and a manual search were utilized to select randomized clinical trials (RCTs) published until March 2019. Overall, 28 RCTs were included: 25 on teeth and three on implants. For plastic periodontal surgery, ADM exhibited a comparable gingival recession reduction (RecRed) and soft tissue thickness (STT) gain to connective tissue graft (CTG). Subgroup analyses revealed that ADM obtained a similar keratinized tissue width (KTW) gain to CTG within 3–6 months postoperative, but significantly less KTW gain at 1–5 years postoperative (P = 0.01, mean difference (MD) −0.86 mm). Analyses comparing ADM with free gingival graft (FGG) demonstrated similar RecRed but significantly more KTW/STT gain favouring FGG (KTW: P = 0.01, MD −1.78 mm; STT: P = 0.01, MD −0.77 mm). Significantly more RecRed and KTW/STT gain were verified in ADM + coronally advanced flap/laterally positioned flap compared with these flaps alone (RecRed: P < 0.00001, MD 0.65 mm; KTW: P = 0.001, MD 0.66 mm; STT: P < 0.00001, MD 0.59 mm). Limited data for implant surgery indicated a similar trend as for periodontal surgery. Concerning patient-reported outcomes, ADM achieved favourable aesthetic appearance, alleviation of dentinal hypersensitivity, and less surgical morbidity. In conclusion, ADM exerted comparable clinical efficacy to autogenous tissue for root coverage procedures, with good long-term stability. However, for soft tissue augmentation, ADM exhibited inferior 3–6-month postoperative outcomes compared with FGG and less long-term stability of KTW gain compared with CTG.     

Subepithelial connective tissue graft for root coverage in smokers and non-smokers: a clinical and histologic controlled study in humans

BACKGROUND: The aim of this study was to evaluate root coverage of gingival recessions and to compare graft vascularization in smokers and non-smokers. METHODS: Thirty subjects, 15 smokers and 15 non-smokers, were selected. Each subject had one Miller Class I or II recession in a non-molar tooth. Clinical measurements of probing depth (PD), relative clinical attachment level (CAL), gingival recession (GR), and width of keratinized tissue (KT) were determined at baseline and 3 and 6 months after surgery. The recessions were treated surgically with a coronally positioned flap associated with a subepithelial connective tissue graft. A small portion of this graft was prepared for immunohistochemistry. Blood vessels were identified and counted by expression of factor VIII-related antigen-stained endothelial cells. RESULTS: Intragroup analysis showed that after 6 months there a was gain in CAL, a decrease in GR, and an increase in KT for both groups (P <0.05), whereas changes in PD were not statistically significant. Smokers had less root coverage than non-smokers (58.02% +/- 19.75% versus 83.35% +/- 18.53%; P <0.05). Furthermore, the smokers had more GR (1.48 +/- 0.79 mm versus 0.52 +/- 0.60 mm) than the non-smokers (P <0.05). Histomorphometry of the donor tissue revealed a blood vessel density of 49.01 +/- 11.91 vessels/200x field for non-smokers and 36.53 +/- 10.23 vessels/200x field for smokers (P <0.05). CONCLUSION: Root coverage with subepithelial connective tissue graft was negatively affected by smoking, which limited and jeopardized treatment results.     

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 × 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.