Adenomatoid odontogenic tumor: Features of ameloblastic-like epithelial cells differentiation, secretion, and the nature of tumor cells products.

BACKGROUND: This study aimed to investigate the differentiation of ameloblastic-like cells and the nature of the secreted eosinophilic materials in adenomatoid odontogenic tumors. METHODS: We studied histological and immunohistochemical characteristics of 20 cases using: cytokeratins 14 and 19, amelogenin, collagen I, laminin, vimentin, and CD34. RESULTS: Rosette cells differentiated into ameloblastic-like cells positioned face-to-face, displaying collagen I-positive material between them. Epithelial cells of the rosettes can differentiate into ameloblastic-like cells. This phenomenon probably occurs due to an induction phenomenon between these cells. The secretion of collagen I is probably a brief event. Amelogenin-positive areas were interspersed by epithelial cells in the lace-like areas, outside the rosettes and distant from the ameloblastic-like cells. CONCLUSIONS: There are at least two types of eosinophilic material in different areas within the tumor, one in the rosette and solid areas and another in lace-like areas. The secreted eosinophilic material in the rosettes and solid areas is probably a product of well-differentiated ameloblastic-like cells. It is positive for collagen I and negative for amelogenin, whereas some eosinophilic materials in the lace-like areas are positive for amelogenin. We hypothesize that the latter eosinophilic material could be a product of odontogenic cuboidal epithelial or intermediate stratum-like epithelial cells.

Use of enamel matrix- derived proteins combined with bone graft for the treatment of intrabony defects: overview of reviews (FRISBEE review) / Uso de proteínas derivadas de la matriz del esmalte combinado con injerto óseo para el tratamiento de defectos intraóseos: resumen estructurado de revisiones sistemáticas (revisión FRISBEE)

Introduction: The use of enamel matrix-derived proteins (EMD) has increased in recent years due to their tissue-inducing properties that support periodontal regeneration. This study is an overview of systematic reviews with FRISBEE methodology on the use of EMD alone or combined with autologous bone graft materials (BGM) in the treatment of intrabony defects. Materials and Methods: A systematic search in the Epistemonikos database was performed. RevMan 5.3 and GRADEpro were used for data analysis and presentation Results: Four systematic reviews and two clinical trials were identified. All studies analysed change in probing depth, clinical attachment level, gingival margin level and bone defect depth (all changes in favour of EMD+BGM groups: mean difference (MD): 0.37 mm more, MD: 0.7 mm more, MD: 0.3 mm less, MD: 0.75 more, respectively). Conclusions: Adding autologous bone graft to EMD to treat intrabony defects showed better results, but not a relevant clinical difference compared to the use of EMD alone.

Introducción: El uso de proteínas derivadas de la matriz del esmalte (EMD) ha aumentado en los últimos años debido a sus propiedades inductoras de tejidos que apoyan la regeneración periodontal. Este estudio es una revisión sistemática de revisiones sistemáticas utilizando metodología FRISBEE sobre el uso de EMD solo o combinado con materiales injerto óseo autólogo (BGM) en el tratamiento de defectos intraóseos. Materiales y Métodos: Se realizó una búsqueda sistemática en la base de datos Epistemonikos. Se utilizaron RevMan 5.3 y GRADEpro para el análisis y la presentación de los datos. Resultados: Se identificaron cuatro revisiones sistemáticas y dos ensayos clínicos. Todos los estudios analizaron el cambio en la profundidad de sondaje, el nivel de inserción clínica, el nivel del margen gingival y la profundidad del defecto óseo (todos los cambios a favor de los grupos EMD+BGM: MD: 0,37 mm más, media de diferencia (MD): 0,7 mm más, MD: 0,3 mm menos, MD: 0,75 más, respectivamente). Conclusión: La adición de injerto óseo autólogo a la EMD para tratar defectos intraóseos mostró mejores resultados, pero no una diferencia clínica relevante en comparación con el uso de la EMD sola.

Gingival recession treatment with enamel matrix derivative associated with coronally advanced flap and subepithelial connective tissue graft: a split-mouth randomized controlled clinical trial with molecular evaluation.

OBJECTIVES: The goal of this study was to evaluate the impact of enamel matrix derivative (EMD) on periodontal healing after root coverage (RC) surgery, involving CAF in combination with SCTG, and to assess the molecular profile, verifying the inflammation level in early stage (1 and 2 weeks). MATERIALS AND METHODS: Thirty-two recessions (RT1) were submitted to periodontal surgery with (test) or without (control) EMD. The clinical parameters analyzed on the day of surgery and 6 months after the surgical procedure were as follows: recession height and width, keratinized tissue height, percentual root coverage, and the gingival thickness of keratinized tissue. Moreover, the main inflammatory biomarkers and growth factors (IL-1ß, IL-6, IL-8, FGF, MIP-1α and ß, PDGF, TNF-α, and VEGF) were evaluated at baseline, 7, and 14 days after procedures. RESULTS: The average root coverage was significantly higher in the test group as compared to the control group (86% vs. 66%, p = 0.008). The test side had significantly lesser final RH compared to the control side (p = 0.01). Also, there was a significant reduction of RW in both groups, with more significant results in the test group. KTH and GT were not significantly different at any time and group. After 14 days, the immunological analysis showed an increase of VEGF (p = 0.03) on the test group compared to the control side. CONCLUSION: The use of EMD in RC surgeries resulted in a significantly higher RC, as well as a significant increase in VEGF expression, suggesting that EMD may contribute to the angiogenic and healing process. CLINICAL RELEVANCE: EMD provided better results in root coverage treatment when associated with CAF and SCTG, beyond a greater releasing of angiogenic growth factor (VEGF), which enhanced the result.

Treatment of intrabony periodontal defects in controlled diabetic patients with an enamel matrix derivative: a split-mouth randomized clinical trial.

OBJECTIVE: This split-mouth randomized controlled trial aimed to evaluate the effect of enamel matrix derivative (EMD) associated with a simplified papilla preservation flap (SPPF) compared to SPPF alone in the surgical treatment of intrabony defects (ID) in type 2 diabetic mellitus (T2DM) patients. MATERIAL AND METHODS: Thirteen patients with controlled T2DM presenting with ID in at least two quadrants were included. In each patient, the test site (TS) was treated with SPPF plus EMD, whereas the control site (CS) was treated only with SPPF. Prior to surgery and at 6 months after intervention, the following parameters were evaluated: clinical attachment level (CAL), probing pocket depth (PPD), and gingival recession (GR). RESULTS: The TS and CS demonstrated a mean CAL gain of 3.31 ± 0.96 mm and 1.61 ± 1.12 mm, and a PPD reduction from 8.15 ± 0.98 to 3.00 ± 0.57 mm and 7.53 ± 0.96 to 4.69 ± 0.63 mm after 6 months, respectively. In both sites, the mean CAL gain and PPD reduction improved significantly after 6 months compared to baseline; however, the improvement was higher in the TS (p < 0.001). CONCLUSIONS: Both surgical procedures presented with clinical improvements in controlled T2DM patients. However, the additional use of EMD showed enhanced clinical results after 6 months with regard to CAL gain and PPD reduction. CLINICAL RELEVANCE: This study showed a better PPD reduction and CAL gain when an EMD was applied in addition to SPPF. Therefore, EMD may be used to enhance clinical outcomes in periodontal ID of controlled T2DM patients.

Enamel matrix derivative effects on palatal mucosa wound healing: Randomized clinical trial.

BACKGROUND: This study was conducted to evaluate the clinical, immunologic, and patient-centered outcomes of enamel matrix protein derivative (EMD) on excisional wounds in palatal mucosa. MATERIALS: Forty-four patients in need of ridge preservation were randomly allocated into two groups: control group (n = 22): open palatal wound after free gingival graft (FGG) harvest and EMD group (n = 22): open palatal wound after FGG harvest that received 0.3 ml of EMD. Clinical and patient-centered parameters were analyzed for 3 months post-treatment. Wound fluid levels of inflammatory markers were assessed 3 and 7 days postoperatively. RESULTS: No significant inter-group difference was observed in remaining wound area and re-epithelialization. EMD and control groups achieved wound closure and re-epithelialization 30 days postoperatively (p < .001), without inter-group differences. Similarly, number of analgesics and Oral Health Impact Profile scores did not present significant inter-group differences (p > .05). EMD appeared to selectively modulate wound fluid levels of monocyte chemoattractant protein-1, macrophage inflammatory protein-1α, matrix metallopeptidase 9, and tissue inhibitor of metalloproteinases-2. CONCLUSION: Within the limits of the present study, it can be concluded that EMD application to excisional palatal wounds using the investigated protocol does not provide clinical healing benefits, despite an apparent modulation of selected inflammatory markers.

Avaliação radiográfica da resposta pulpar e periapical de dentes de cães ao Emdogain® após pulpotomia / Radiographic evaluation of pulpal and periapical response of dogs teeth to Emdogain® used as pulpotomy agent

Introdução: O derivado da matriz do esmalte (Emdogain®) é um extrato de proteína usado para cicatrização periodontal. Objetivo: O objetivo desse estudo foi avaliar radiograficamente a resposta pulpar e periapical de dentes de cães após pulpotomia e uso do gel derivado da matriz do esmalte (Emdogain®). Métodos: A pulpotomia foi realizada em 30 dentes (60 raízes) de 3 cães, e o tecido pulpar remanescente foi recoberto com os seguintes materiais: Grupos 1 e 4: gel derivado da matriz do esmalte (Emdogain®); Grupos 2 e 5: hidróxido de cálcio; Grupos 3 e 6: óxido de zinco e cimento de eugenol. Após 10 dias (Grupos 1-3) e 75 dias (Grupos 4-6) foram obtidas radiografias periapicais e a avaliação radiográfica foi realizada considerando-se: a integridade da lâmina dura, presença de áreas de rarefação óssea periapical, reabsorção radicular (interna e externa) e formação de ponte de dentina. Resultados: No período de 10 dias, todos os espécimes dos Grupos 1-3 apresentaram ausência de rarefação óssea periapical, reabsorção radicular (interna e externa) e formação de ponte dentinária. No período de 75 dias, os Grupos 4-6 não apresentaram formação de ponte dentinária em nenhum espécime. Áreas de rarefação óssea periapical foram observadas em 100% das raízes no Grupo 4, 62,5% das raízes no Grupo 6 e em 25% das raízes nos Grupos 5. Conclusão: O uso do gel derivado da matriz do esmalte (Emdogain®) como material para capeamento após a pulpotomia levou à formação de lesões periapicais e não induziu a deposição de tecido mineralizado (AU).

Introduction: The enamel matrix derivative (Emdogain®) is a protein extract used for periodontal healing. The objective of this study was to evaluate radiographically the pulpal and periapical response of dogs teeth after pulpotomy and use of enamel matrix derivative gel (Emdogain®). Methods: Pulpotomy was performed in 30 teeth (60 roots) from 3 dogs and the remaining pulp tissue was capped with the following materials: Groups 1 and 4: enamel matrix derivative gel (Emdogain®); Groups 2 and 5: calcium hydroxide; Groups 3 and 6: zinc oxide and eugenol cement. After 10 days (Groups 1-3) and 75 days (Groups 4-6) periapical radiographs were obtained and the radiographic evaluation was performed considering the integrity of the lamina dura, presence of areas of periapical bone rarefaction, root resorption (internal and external) and dentin bridge formation. Results: In the 10- day period, all specimens in Groups 1-3 presented absence of periapical bone rarefaction, absence of root resorption (internal and external) and absence of dentin bridge formation. In the 75-day period, Groups 4-6 did not present dentin bridge formation in any specimen. Periapical bone rarefaction areas were observed in 100% of the roots in Group 4, 62,5% of the roots in Group 6 and in 25% of the roots in Groups 5. Conclusion: The use of enamel matrix derivative gel (Emdogain®) as a capping material after pulpotomy lead to formation of periapical lesions and did not induce deposition of mineralized tissue(AU).

Radiotherapy changes acquired enamel pellicle proteome in head and neck cancer patients.

OBJECTIVES: To evaluate in vivo the proteomic profile of the acquired enamel pellicle (AEP) in patients with head and neck cancer (HNC) before, during and after radiotherapy. METHODS: Nine patients, after prophylaxis, had their AEPs collected before (BRT), during (DRT; 2-5 weeks) and after (ART; 3-4 months) radiotherapy. AEP was also collected from nine healthy patients (Control). The proteins were extracted in biological triplicate and processed by label-free proteomics. RESULTS: Statherin was increased more than 9-fold and several hemoglobin subunits were increased more than 5-fold DRT compared to BRT, while lactotransferrin, proline-rich proteins, cystatins, neutrophil defensins 1 and 3 and histatin-1 were decreased. ART, there was an increase in lactotransferrin and several isoforms of histones, while statherin and alpha-amylase proteins were decreased. MOAP-1 was exclusively found ART in comparison to BRT. When compared to Control, AEP of patients BRT showed an increase in proteins related to the perception of bitter taste, mucin-7 and alpha-amylases, while cystatin-S was decreased. CONCLUSIONS: HNC and radiotherapy remarkably altered the proteome of the AEP. Antibacterial and acid-resistant proteins were decreased during radiotherapy. CLINICAL SIGNIFICANCE: Our results provide important information for designing more effective dental products for these patients, in addition to contributing to a better understanding of the differential protective roles of the AEP proteins during radiotherapy. Moreover, some proteins identified in the AEP after radiotherapy may serve as prognostic markers for survival of HNC patients.

Does enamel matrix derivative application provide additional clinical benefits in the treatment of maxillary Miller class I and II gingival recession? A systematic review and meta-analysis.

OBJECTIVE: This review aimed to evaluate the effects of enamel matrix derivative (EMD) in association with coronally advanced flap (CAF) or CAF + connective tissue graft (CTG) when compared with CAF alone or CAF + CTG for the treatment of gingival recessions (GR) in maxillary teeth. METHODS: Five databases and gray literature were searched up to April 2020, to find randomized clinical trials comparing the clinical effects of CAF + EMD versus CAF alone (first group) or CAF + CTG + EMD versus CAF + CTG (second group) in the treatment of Miller class I and II or Cairo type I gingival recessions (GR). Random effects model of mean differences was used to determine the GR reduction, gain in keratinized tissue width (KTW), and gain in clinical attachment level (CAL). The trial sequential analysis (TSA) was implemented to determine the optimal information size (OIS) and imprecision using the GRADE approach. Bayes factors were calculated as complementary statistical evidence of p value. RESULTS: From 1349 titles identified, 9 trials representing 336 GR were included. The meta-analysis showed a statistically significant difference for GR reduction and CAL gain in favor CAF + EMD (p ≤ 0.05). The additional effect of EMD showed a statistically significant difference in GR reduction in favor CAF + CTG + EMD (p ≤ 0.05). The differences in KTW gain proved to be not statistically significant in both comparison groups. The OIS were not met among meta-analyses. Evidence certainty according the GRADE approach proved to be moderate for GR reduction and gain in CAL, but very low for gain in KTW. CONCLUSION: The adjunctive application of EMD in the treatment of GR in maxillary teeth either with CAF or CTG provided moderate certainty evidence in favor of their use for reduction in GR and gain in CAL at 6 and 12 months. However, their effect on the increase in keratinized tissue band height showed very low evidence certainty for its use. CLINICAL RELEVANCE: To know if EMD could improve the results for root coverage.

Clinical, radiographic, and patient-centered outcomes after use of enamel matrix proteins for the treatment of intrabony defects in patients with aggressive periodontitis: A 12-month multicenter clinical trial.

BACKGROUND: The aim of this study was to evaluate the clinical, radiographic and patient-centered results of enamel matrix derivative (EMD) therapy in intrabony defects in aggressive periodontitis (AgP) patients and compare them with those in chronic periodontitis (CP) patients. METHODS: Sixty intrabony defects in AgP and CP patients associated with ≥ 6 mm residual probing pocket depth (PPD) were included and randomly assigned to one of three groups: AgP+CS (conservative surgery) (n = 20); AgP+CS/EMD (n = 20); CP+CS/EMD (n  =  20). Clinical parameters were measured at baseline and after 6 and 12 months. Defect resolution (DR) and bone filling (BF) were used for radiographic analysis. The quality of life was recorded at baseline and 6 months using OHIP-14 and VAS scale in the early post-therapy period. RESULTS: PPD and relative clinical attachment level (rCAL) improved for all groups during follow-up (P ≤ 0.05), and AgP+CS/EMD presented a higher rCAL gain (2.4 ± 1.0 mm) when compared to AgP control patients (1.6 ± 1.6 mm, P ≤ 0.05) after 12 months. No difference was observed between AgP+CS/EMD and CP+CS/EMD groups (P > 0.05). No radiographic differences were observed among groups at any time point (P > 0.05). All the groups reported a positive impact on OHIP-14 total score, without differences among them. CONCLUSIONS: EMD therapy of intrabony defects promotes additional benefits in AgP patients, presenting a similar regeneration rate compared to CP patients, and has proven to be a viable therapy for the treatment of individuals with AgP.

Expression of enamel proteins in human dental pulp stem cells by the effect of extracellular matrix / Expresión de proteínas de esmalte en células madre de pulpa dental humana por el efecto de matriz extracelular

SUMMARY: Mesenchymal stem cells are present in adult tissues such as the human dental pulp. They are pluripotent and can differentiate into various specialized cell types in vitro through appropriate stimuli. Ameloblasts produce human tooth enamel only during embryonic development before tooth eruption, so endogenous regeneration is not possible. Various efforts have been aimed at generating natural or artificial substitutes for dental enamel with properties similar to the specific components of said tissue. The purpose of this study was to induce human dental pulp stem cells to produce enamel proteins using extracellular matrix derived from the rat tail tendon and pigskin. Primary cultures of human dental pulp stem cells were established and characterized by RT-PCR and immunofluorescence, using mesenchymal cell markers such as CD14, CD40, CD44, CD105, and STRO-1. The cells were then incubated with the extracellular matrix for fourteen days and labeled with specific antibodies to detect the expression of dental enamel proteins such as amelogenin, ameloblastin, enamelisin, tuftelin, and parvalbumin, characteristics of the phenotype of ameloblasts. This work demonstrated a positive effect of the extracellular matrix to induce the expression of enamel proteins in the stem cells of the human dental pulp.

RESUMEN: Las células madre mesenquimales están presentes en los tejidos adultos como la pulpa dental humana. Son pluripotentes y pueden diferenciarse en varios tipos de células especializadas in vitro a través de estímulos adecuados. Los ameloblastos producen esmalte dental humano sólo durante el desarrollo embrionario antes de la erupción dental, por lo que no es posible su regeneración endógena. Varios esfuerzos se han orientado a generar sustitutos naturales o artificiales de esmalte dental con propiedades similares a los componentes específicos de este tejido. El propósito de este estudio fue inducir células madre de pulpa dental humana para producir proteínas del esmalte dental a través del estímulo de matriz extracelular derivada del tendón de la cola de rata y piel de cerdo. Se establecieron cultivos primarios de células madre de pulpa dental humana y se caracterizaron por RT-PCR e inmunofluorescencia utilizando marcadores de células mesenquimales como CD14, CD40, CD44, CD105 y STRO-1. Posteriormente, las células se incubaron con matriz extracelular durante un período de catorce días y se marcaron con anticuerpos específicos para detectar la expresión de proteínas de esmalte dental como amelogenina, ameloblastina, enamelisina, tuftelina y parvalbúmina, las cuales son características del fenotipo de ameloblastos. Este trabajo demostró el efecto positivo que tiene el empleo de la matriz extracelular para inducir la expresión de proteínas de esmalte en las células pluripotenciales de la pulpa dental humana.

Genes in the pathway of tooth mineral tissues and dental caries risk: a systematic review and meta-analysis.

OBJECTIVES: To perform a systematic review of the literature, investigating the influence of tooth mineral tissues genes on dental caries. MATERIALS AND METHODS: Five databases were searched. Only human studies with cross-sectional, longitudinal, and case-control design were included. Meta-analysis was performed for each polymorphism, providing allele and genotype estimates. A meta-analysis was performed, pooling several polymorphisms for each gene. A Funnel Plot and Egger's test were also performed. RESULTS: A total of 1124 records were found. Of these, 25 papers were included in the systematic review and 18 in the meta-analysis. Most of the studies (52%) were of medium quality. With regard to the allele analysis, the T allele of rs134136 (TFIP11) (OR 1.51; 95%CI 1.02-2.22) showed an association with high experience of caries and the summarization of polymorphisms investigated in the TFIP11 gene, after exclusion of SNP linkage disequilibrium, showed an association with caries experience (OR 1.64; 95%CI 1.08-2.50). An analysis of the homozygous genotype did not show any significant association. The pooled SNPs of AMBN showed associations with caries (OR 0.45; 95%CI 0.29-0.72). The pooled polymorphisms of AMELX were associated with caries experience (OR 1.78; 95%CI 1.23-2.56). In the analysis of the homozygous genotype, no SNP showed a significant association. Egger's test showed no significant publication bias for all models (p > 0.05). CONCLUSION: The present findings showed that the genes TFIP11, AMBN, and AMELX play an important role in dental caries. CLINICAL RELEVANCE: Several single nucleotide polymorphisms related to the genes in the formation of tooth mineral are linked to the occurrence of dental caries, and these genes have proved to be important for an explanation of differences in the risk of dental caries.

The use of enamel matrix derivative in the treatment of class II furcation defects: systematic review and meta-analysis.

OBJECTIVE: To evaluate the effect of enamel matrix derivative (EMD) in the regeneration of class II furcation defects, used alone or in conjunction with biomaterials. METHODS: Electronic database searches and hand searches were carried out and double-blind randomized controlled trials evaluating the use of EMD in class II furcation therapy were included, and a meta-analysis comparing the effect of open flap debridement (OFD) + ßTCP/HA with and without EMD was carried out. RESULTS: The initial search resulted in a total of 298 articles, after removing the duplicates and exclusions after analysing the titles, abstracts and full text, five studies were included for the qualitative synthesis and two for the quantitative analysis. The meta-analysis showed no statistical difference when comparing OFD + ßTCP/ HA with or without EMD in the treatment of furcation defects in any of the evaluated parameters. According to GRADE, the certainty of the evidence for the variables evaluated was moderate. CONCLUSION: The therapeutic modalities studied improved the periodontal clinical parameters of class II furcations, but the use of EMD in the treatment of these defects did not contribute to a clinical improvement that justified its use associated with the therapies/biomaterials. It is important to emphasize the need for more studies with larger samples to increase the certainty of the evidence reported in this review.

Novel LRAP-binding partner revealing the plasminogen activation system as a regulator of cementoblast differentiation and mineral nodule formation in vitro.

Amelogenin isoforms, including full-length amelogenin (AMEL) and leucine-rich amelogenin peptide (LRAP), are major components of the enamel matrix, and are considered as signaling molecules in epithelial-mesenchymal interactions regulating tooth development and periodontal regeneration. Nevertheless, the molecular mechanisms involved are still poorly understood. The aim of the present study was to identify novel binding partners for amelogenin isoforms in the cementoblast (OCCM-30), using an affinity purification assay (GST pull-down) followed by mass spectrometry and immunoblotting. Protein-protein interaction analysis for AMEL and LRAP evidenced the plasminogen activation system (PAS) as a potential player regulating OCCM-30 response to amelogenin isoforms. For functional assays, PAS was either activated (plasmin) or inhibited (ε-aminocaproic acid [aminocaproic]) in OCCM-30 cells and the cell morphology, mineral nodule formation, and gene expression were assessed. PAS inhibition (EACA 100 mM) dramatically decreased mineral nodule formation and expression of OCCM-30 differentiation markers, including osteocalcin (Bglap), bone sialoprotein (Ibsp), osteopontin (Spp1), tissue-nonspecific alkaline phosphatase (Alpl) and collagen type I (Col1a1), and had no effect on runt-related transcription factor 2 (Runx2) and Osterix (Osx) mRNA levels. PAS activation (plasmin 5 µg/µl) significantly increased Col1a1 and decreased Bglap mRNA levels (p < .05). Together, our findings shed new light on the potential role of plasminogen signaling pathway in the control of the amelogenin isoform-mediated response in cementoblasts and provide new insights into the development of targeted therapies.

Treatment of dehiscence-type defects with collagen matrix and/or enamel matrix derivative: Histomorphometric study in minipigs.

BACKGROUND: This study aimed to evaluate, histomorphometrically, the use of collagen matrix (CM) and/or enamel matrix derivative (EMD) for the treatment of dehiscence-type recession defects in minipigs. METHODS: Eight healthy, male, young BR-1 minipigs, with no periodontal disease were treated. Bilateral dehiscence-type defects were surgically created on the buccal of the mandibular premolars (PI and PII). After 30 days, the defects were randomly assigned to four groups: coronally advanced flap (CAF); CAF + CM; CAF + EMD; and CAF + CM + EMD (split-mouth design). The evaluated parameters (mm): total defect length; new cementum (NC); new bone (NB); gingival margin position; total epithelium length; epithelium on the root; connective tissue adaptation; and soft tissue thickness (STT). RESULTS: The EMD-treated groups showed a superior length of NC [4.13 ± 1.22 (CAF + EMD); 3.95 ± 1.11 (CAF + CM + EMD); 2.94 ± 0.77 (CAF + CM); 2.72 ± 0.81 (CAF), P = 0.02] and NB [3.21 ± 0.68 (CAF + CM + EMD); 3.01 ± 0.56 (CAF + EMD); 2.15 ± 0.47 (CAF + CM); 2.29 ± 0.82 (CAF), P = 0.005]. The CAF and CAF + CM groups showed a superior epithelial length when compared to EMD-treated groups after 3 months. A superior STT was observed for CAF + CM + EMD group (1.5 ± 0.33) when compared with the other groups [1.09 ± 0.26 (CAF + EMD); 1.04 ± 0.34 (CAF + CM); and 1.14 ± 0.29 (CAF), P = 0.03]. CONCLUSION(S): The results of the present study indicate that EMD application, irrespective of the combination with CM, may improve the periodontal regeneration of dehiscence-type defects in this animal model.

Treatment of an Advanced Gingival Recession Involving the Apex of the Tooth: Periodontal Plastic, Endodontic Surgical Approach With a Laterally Stretched Flap and a Connective Tissue Graft.

INTRODUCTION: This case report presents the successful multidisciplinary treatment of a maxillary lateral incisor with a deep and narrow recession involving the root apex associated with pulpal necrosis. The tooth initially considered with a hopeless prognosis, was treated with a combined periodontal plastic, regenerative, and endodontic surgical procedure. CASE PRESENTATION: A recently reported technique, the laterally stretched (LAST) flap with a connective tissue graft (CTG) technique for root coverage, was combined with enamel matrix derivative (EMD) for periodontal regeneration of the periapical lesion, that complemented an apicoectomy with retrograde sealing. The 6-year follow-up evidenced root coverage (RC) of 91.6% and increased keratinized tissue. Clinical and radiographic evaluation showed resolution of the periapical process. CONCLUSIONS: A severe gingival recession with endodontic involvement can be repaired if adequate control of the endodontic infection is obtained. The LAST flap, originally described for lower anterior teeth, was used successfully in a maxillary tooth, under extreme circumstances.

Deproteinization of primary enamel with sodium hypochlorite before phosphoric acid etching.

The aim of this study was to evaluate the deproteinization of primary enamel by analyzing etching pattern types, with and without the application of 5% NaOCl before acid etching with 37% H3PO4. Fifteen extracted human primary molars were randomly selected for the present in vitro study; 1mm x 1mm blocks were prepared and divided into two groups (n = 21). These groups were treated as follows: Group A- Acid Etching with 37% H3PO4 gel for 15 s; Group B- 5% NaOCl for 60 s + Acid Etching with 37% H3POfor 15 s. The specimens were prepared for scanning electron microscopy analysis. The images were evaluated for quality types I and II etching of the enamel surface using ImageJ software. Datasets were checked for normality by Kolgomorv-Smirnov test and the nonparametric unpaired Mann-Whitney test was applied. The mean surface area of type I and II etching pattern values was 1922.314 µm2for Group A and 3840.473 µm2Group B. We conclude that deproteinization with 5% NaOCl prior to acid etching can be used to increase the area of adhesion and the quality of the etching pattern.

El objetivo del estudio fue evaluar la desproteinización del esmalte primario a través de los tipos de patrones de grabado, con y sin NaOCl 5% utilizado antes del grabado ácido con H3PO4 37%. Quince dientes primarios humanos extraídos se seleccionaron al azar para el presente estudio in vitro, se prepararon bloques de 1mm x 1 mm y se dividieron en dos grupos (n = 21). Estos grupos se trataron de la siguiente manera: Grupo A: Grabado ácido con H3PO4 37% en gel durante 15 segundos; Grupo B: NaOCl 5% durante 60 segundos + Grabado ácido con H3PO4 37% durante 15 segundos. Las muestras se prepararon para el análisis de microscopía electrónica de barrido. Las imágenes obtenidas se evaluaron principalmente por la calidad de los grabados tipo I y II de la superficie del esmalte primario, utilizando el software Image J. Los datos se analizaron en cuanto a su normalidad mediante la prueba de Kolgomorv-Smirnov, se utilizó pruebas no paramétricas: Prueba de Mann-Whitney no pareada. Como resultado, se encontró que el área de superficie media de los valores de patrón de grabado de tipo I y II para el Grupo A era 1922,314 µm2 y el Grupo B era 3840,473 µm2. Finalmente, llegamos a la conclusión de que se puede usar la desproteinización con NaOCl 5% antes del grabado ácido para aumentar el área de adhesión y la calidad del patrón de grabado.

Ectodermal and ectomesenchymal marker expression in primary cell lines of complex and compound odontomas: a pilot study.

BACKGROUND: Odontomas are odontogenic tumors with hamartoma features that are classified as compound or complex. Our objective was to characterize the proliferation of ectodermal and ectomesenchymal profile markers of primary cell cultures of complex and compound odontomas. METHODS: Four samples of compound odontomas (OdCm) and three of complex odontomas (OdCx) were obtained from patients attending the Oral Pathology and Medicine Clinic of the Graduate Dental School, National Autonomous University of Mexico for primary culture generation. MTT, immunocytochemistry and RT-PCR assays of CD34, Sox2, Amel, Ambn, p21, EDAR, Msx1, Msx2, Pax9, RUNX2, BSP, OPN, Barx1 and GAPDH (control) were performed. Additionally, six paraffin-embedded odontomas were obtained for immunocytochemistry and RT-PCR validation assays. The mean and standard deviation were determined, and ANOVA and Kruskall-Wallis tests were performed. RESULTS: Cultured compound odontoma exhibited higher proliferation, and an ectomesenchymal immunocytochemistry profile with predominant expression of Amel, BSP, Pax9, EDAR, Barx and Msx2; in complex cultured odontoma Sox2, CD34, RUNX2 and OPN predominated. Our statistical analysis showed a significant difference in PCR analysis (P<0.05) for OPN and CD34. Paraffin-embedded odontomas showed similar pattern with difference for NGFR and Sox2 for immunohistochemistry and EDAR, BARX1 and PAX9 for RT-PCR assays. CONCLUSIONS: The results suggested heterogeneous behavior for both odontoma cell lines, because in compound odontomas predominant biomarkers are related to the enamel knot, late-stage odontogenesis and ectomesenchymal interactions; and in complex odontoma the significant expression of CD34 and OPN could be responsible for the difference behavior and mineralized amorphous structure.

Experimental and clinical studies on regenerative periodontal therapy.

The recognition of a periodontal therapy as a regenerative procedure requires the demonstration of new cementum, periodontal ligament, and bone coronal to the base of the defect. A diversity of regenerative strategies has been evaluated, including root surface conditioning, bone grafts and bone substitute materials, guided tissue regeneration, enamel matrix proteins, growth/differentiation factors, combined therapies and, more recently, tissue-engineering approaches. The aim of this chapter of Periodontology 2000 is to review the research carried out in Latin America in the field of periodontal regeneration, focusing mainly on studies using preclinical models (animal models) and randomized controlled clinical trials. This review may help clinicians and researchers to evaluate the current status of the therapies available and to discuss the challenges that must be faced in order to achieve predictable periodontal regeneration in clinical practice.

The effect of enamel matrix derivatives on root coverage: a 12-month follow-up of a randomized clinical trial.

Subepithelial connective tissue grafts (SCTGs) with a coronally advanced flap (CAF) are accepted as the gold standard for covering denuded root surfaces. In recent years, enamel matrix derivatives (EMDs) have been used for their regenerative potential in periodontics. The aim of this split-mouth and randomized controlled study was to assess the clinical and aesthetical impacts of EMD application in combination with SCTG+CAF in patients with Miller's Class I and II gingival recessions in contralateral canines of the maxilla. Participants who underwent SCTG+CAF+EMD application were identified as the test group (n = 19) and those who underwent SCTG+CAF as control group (n = 19). The outcome parameters were recession depth/width, root coverage percentage, and root coverage aesthetic score (RES). RES was evaluated by two calibrated blind periodontists one year after the treatment. Statistically significant root coverage percentage was observed at one year post-treatment for both groups (p < 0.05). However, significant differences between the groups were not observed in terms of total RES and complete root coverage rate (p > 0.05). The test group had significantly better results than the control according to the soft tissue texture and mucogingival junction alignment results (p < 0.05). These results indicate that EMDs contribute to the healing of soft tissue without scarring. As a result of better wound healing, the EMD-added group exhibited better results in terms of the harmony of the mucogingival junction between adjacent teeth. This paper is the first split-mouth study in which SCTG+CAF and SCTG+CAF+EMD were compared using RES in bilateral canines.

Analysis of Polymorphisms in Genes Differentially Expressed in the Enamel of Mice with Different Genetic Susceptibilities to Dental Fluorosis.

Genes expressed during amelogenesis are candidates to increase the risk of dental fluorosis (DF). Thus, this study aimed to evaluate the association between polymorphisms in enamel development genes and susceptibility to DF in mice. Mice of both sexes, representing strains 129P3/J (n = 20; resistant to DF) and A/J (n = 20; susceptible to DF), were divided into 2 groups. Each strain received a diet with a low concentration of fluoride (F) and drinking water containing 0 or 50 mg/L of F for 6 weeks. Clinical evaluation and analysis of Vickers enamel microhardness of the incisors were performed. Livers were collected for genomic DNA extraction. Seventeen genetic polymorphisms in Amelx, Ambn, Ambn, Col14a1, Col1a1, Col5a2, Enam, Fam20a, Fam83h, Foxo1, Klk4, Mmp20, Serpinf1, Serpinh1, Smad3, Tuft1, and Wdr72 were genotyped by real-time PCR using Taqman chemistry. Overrepresentation of alleles and genotypes in DF was evaluated using the χ2 test with an alpha of 5%. The clinical aspects of the enamel and the surface enamel microhardness confirmed the DF condition. In the polymorphisms rs29569969, rs13482592, and rs13480057 in Ambn, Col14a1, and Mmp20, respectively, genotype and allele distributions were statistically significantly different between A/J and 129P3/J strains (p < 0.05). In conclusion, polymorphisms in Ambn, Col14a1, and Mmp20 are associated with the susceptibility to DF.