Histological Techniques for the Study of the Dentogingival Junction: A Scoping Review Using the Anatomical Quality Assurance Checklist (AQUA) / Técnicas Histológicas para el Estudio de la Unión Dentogingival: Una Revisión de Alcance Utilizando el Anatomical Quality Assurance Checklist (AQUA)

SUMMARY: The dentogingival junction (DGJ) is an adaptation of the oral mucosa composed of epithelial and connective tissues intimately related with the mineralised tissues of the tooth. The histological evidence available is mainly based on studies in animals, separate evaluations of hard and soft tissues, and studies using conventional histological techniques that eliminate the enamel from preparations. The aim of this study was to carry out a review of the existing evidence on histological techniques available for study of the tooth and periodontium in conjunction in humans. A scoping review was carried out of the available literature referring to study of the tooth and the periodontium in conjunction in humans, in the Web of Science (WoS), EMBASE, Scopus and SciELO databases, using the terms "Histological Techniques"[Mesh]) and "Epithelial Attachment"[Mesh]. One hundred and fifty-nine articles were found, of which 54 were selected for full- text reading. Ten were finally included in the qualitative synthesis, and we applied the Anatomical Quality Assurance (AQUA) checklist for analysis the methodological quality of the selected articles. The results showed that the only articles with a low risk of bias in all five domains according to the AQUA criteria corresponded to Silva et al. (2011) and Agustín-Panadero et al. (2020). Finally, we conclude that the quality of the histological sections to observe tissues that simultaneously contain the tooth and the periodontium, is conditioned by the selected technique and by the care required in certain specific tasks during the histological processing of the samples.

La unión dentogingival (DGJ) es una adaptación de la mucosa oral compuesta por tejidos epitelial y conectivo íntimamente relacionados con los tejidos mineralizados del diente. La evidencia histológica disponible se basa principalmente en estudios en animales, evaluaciones separadas de tejidos duros y blandos y estudios utilizando técnicas histológicas convencionales que eliminan el esmalte de las preparaciones. El objetivo de este estudio fue realizar una revisión de la evidencia existente sobre las técnicas histológicas disponibles para el estudio del diente y el periodonto en conjunto en humanos. Se realizó un scoping review de la literatura disponible referente al estudio del diente y el periodonto en conjunto en humanos, en las bases de datos Web of Science (WoS), EMBASE, Scopus y SciELO, utilizando los términos "Histological Techniques"[Mesh]) y "Epithelial Attachment"[Mesh]. Se encontraron 159 artículos, de los cuales 54 fueron seleccionados para lectura de texto completo. Diez fueron finalmente incluidos en la síntesis cualitativa, y se aplicó la lista de verificación Anatómica Quality Assurance (AQUA) para el análisis de la calidad metodológica de los artículos seleccionados. Los resultados mostraron que los únicos artículos con bajo riesgo de sesgo en los cinco dominios según los criterios AQUA correspondían a Silva et al. (2011) y Agustín-Panadero et al. (2020). Finalmente, concluimos que la calidad de los cortes histológicos para observar los tejidos que contienen simultáneamente el diente y el periodonto, está condicionada por la técnica seleccionada y por el cuidado requerido en ciertas tareas específicas durante el procesamiento histológico de las muestras.

Determinación de parámetros estéticos gingivales y dentarios en dientes anterosuperiores / Determination of gingival and dental esthetic parameters in anterosuperior teeth

La odontología estética no es una disciplina especial o área de la odontología en sí misma, pero con consideraciones funcionales y biológicas, representa uno de los objetivos de las intervenciones de tratamiento dental, que abarca todas las áreas de especialidad, desde la odontología preventiva y restaurativa hasta la prostodoncia, ortodoncia, periodoncia, como, así como la cirugía oral y maxilofacial. El cénit gingival es un importante componente de la sonrisa y su estudio sigue siendo muy relevante en la odontoestética internacional. En el presente trabajo se determinaron distancias del cenit al eje longitudinal y se correlacionaron con otros parámetros gingivales, se establecieron diferencias en las alturas de las papilas interdentales y se correlacionaron los datos métricos de las piezas dentarias anteriores de la población estudiada y los datos conocidos con el fin de obtener datos estadísticos relevantes. Los datos mesurables fueron obtenidos de pacientes de ambos sexos, (18 ­ 25) años, con piezas dentarias del grupo anterior y superior a saber: incisivos centrales, incisivos laterales y caninos superiores, normalmente implantados, libres de lesiones o restaruración, ausencia de enfermedad gingivoperiodontal y sin tratamientos ortodoncicos. El trabajo observacional, descriptivo y tranversal arrojó resultados basados en la estadística preponderante. Provee dimensiones y proporciones de dientes maxilares que pueden adaptarse a pacientes individuales en relación con parámetros establecidos en la odontoestética. Estos datos pueden ser pautas útiles para el diagnóstico y la planificación del tratamiento (especialmente cirugía periodontal) en la dentición maxilar (AU)

A esthetic dentistry is not a special discipline or area of dentistry itself, but with functional and biological considerations, it represents one of the objectives of dental treatment interventions, which covers all areas of specialty, from preventive and restorative dentistry up to prosthodontics, orthodontics, periodontics, as well as oral and maxillofacial surgery. The gingival cenith is an important component of the smile and its study remains very relevant in international dentistry. In this work, distances from the cenith to the longitudinal axis were determined and correlated with other gingival parameters, differences in the heights of the interdental papillae were established and the metric data of the anterior teeth of the studied population were correlated and the known data with in order to obtain relevant statistical data. The measurable data were obtained from patients of both sexes, (18 - 25) years, with teeth of the anterior and superior group, namely: central incisors, lateral incisors and upper canines, normally implanted, free of lesions or restoration, absence of disease gingivoperiodontal and without orthodontic treatments. The observational, descriptive and transverse work produced results based on the preponderant statistics. It provides dimensions and proportions of maxillary teeth that can be adapted to individual patients in relation to parameters established in odontoesthetics. These data can be useful guidelines for diagnosis and treatment planning (especially periodontal surgery) in the maxillary dentition (AU)

Three-dimensional periodontal tissue regeneration using a bone-ligament complex cell sheet.

Periodontal tissue is a distinctive tissue structure composed three-dimensionally of cementum, periodontal ligament (PDL) and alveolar bone. Severe periodontal diseases cause fundamental problems for oral function and general health, and conventional dental treatments are insufficient for healing to healthy periodontal tissue. Cell sheet technology has been used in many tissue regenerations, including periodontal tissue, to transplant appropriate stem/progenitor cells for tissue regeneration of a target site as a uniform tissue. However, it is still difficult to construct a three-dimensional structure of complex tissue composed of multiple types of cells, and the transplantation of a single cell sheet cannot sufficiently regenerate a large-scale tissue injury. Here, we fabricated a three-dimensional complex cell sheet composed of a bone-ligament structure by layering PDL cells and osteoblast-like cells on a temperature responsive culture dish. Following ectopic and orthotopic transplantation, only the complex cell sheet group was demonstrated to anatomically regenerate the bone-ligament structure along with the functional connection of PDL-like fibers to the tooth root and alveolar bone. This study represents successful three-dimensional tissue regeneration of a large-scale tissue injury using a bioengineered tissue designed to simulate the anatomical structure.

Periotestometry and tissue hydration. How are these indicators related?

The mobility of teeth in terms of periotestometry and hydration of periodontal tissues in terms of bioimpedance spectrometry were studied in healthy volunteers without dental and concomitant somatic diseases. It was found that teeth of these subjects have both low and pathological mobility. It was also revealed as increased hydration (edema), indicating the presence of inflammation, and reduced hydration, indicating atrophic processes in periodontal tissues. A comparison of the data of periotestometry and bioimpedance spectrometry showed that the indicators of mobility of the teeth and hydration of the periodontal tissues reflect different characteristics of the functional state of dentoalveolar system, and can be used as complementary in the diagnostic studies.

Assessment of Periodontal Biotype in a Young Chinese Population using Different Measurement Methods.

Periodontal biotype is used to describe the morphological characteristics of periodontal tissues and is closely related to periodontal health and prognosis of many dental treatments. This study was undertaken to explore the periodontal biotype distribution in a young Chinese population and to evaluate the accuracy of different methods for gingival thickness (GT) measurement. A total of 372 teeth from 31 periodontally healthy subjects were included. GT was measured simultaneously by probe transparency, transgingival probing and cone-beam computed tomography (CBCT). Some other anatomic parameters, including crown width/crown length ratio, attached gingival width, labial bone thickness and papilla volume were recorded for periodontal biotype classification. As found by probe transparency, the gingivae of 222 teeth (59.68%) were thick, while those of 150 teeth (40.32%) were thin. The mean GT of included subjects was 1.03 ± 0.31 mm as measured by transgingival probing and 1.03 ± 0.24 mm as measured by CBCT. Four groups were identified by cluster analysis. Thick-flap biotype, average-scalloped biotype, average-flap biotype and thin-scalloped biotype comprised 137 teeth (36.83%), 96 teeth (25.81%), 39 teeth (10.48%) and 100 teeth (26.88%), respectively. These results demonstrate that the most common periodontal biotype in this young Chinese population was the thick-flap type with low aesthetic risk.

Novel Collagen Matrix to Increase Tissue Thickness Simultaneous with Guided Bone Regeneration and Implant Placement in Esthetic Implant Sites: A Feasibility Study.

The purpose of this case series was to assess safety and feasibility of a novel resorbable collagen matrix (CMX) to enhance tissue thickness simultaneous with implant placement and guided bone regeneration (GBR) in esthetic sites over an 8-week healing period. Soft tissue thickness at implant sites and adjacent teeth was monitored with an ultrasonic device. Overall tissue contour changes were assessed by sequential digital surface model superimpositions. Periodontal parameters and patient-related outcomes revealed no significant changes. Combining a novel CMX and GBR revealed a significant soft tissue thickness increase of 1.56 mm at implant sites after 8 weeks, with no significant decrease between 4 and 8 weeks. The overall tissue contour increase was most significant at a distance of 5 mm from the mucosal margin, corresponding to a tissue increase at the implant shoulder area. No effect was observed at adjacent teeth after 8 weeks.

Profilometric changes of peri-implant tissues over 5 years: A randomized controlled trial comparing a one- and two-piece implant system.

OBJECTIVES: To assess the profilometric changes of the buccal soft tissues between baseline and 5 years of loading using a one- and two-piece dental implant system. MATERIALS AND METHODS: Sixty patients randomly received dental implants of either a two-piece type (BRA) or a one-piece type (STM). Casts were obtained at baseline (after crown insertion), at the 1-year and at the 5-year follow-up. Stereolithography files were obtained from the casts for digital superimposition. One implant and the contralateral natural tooth were selected for the analysis. Thirty-three patients (BRA = 16; STM = 17) were included. Measurements included changes for crown height (CH) and estimated soft tissue thickness, as well as the profilometric change at the implant and the tooth site. Nonparametric methods were applied for the statistical analyses and medians and quartiles presented. RESULTS: The BRA group lost -0.39 mm and the STM group lost -0.40 mm of volume between baseline and the 5-year follow-up at the implant site (p > 0.05). The tooth site lost -0.18 mm (BRA) and -0.12 mm (STM) (p > 0.05). Volume differences between implants and teeth amounted to -0.05 mm (baseline to 1 year) and -0.25 mm (baseline to 5 years) for BRA, while for STM, the values were 0.03 mm (baseline to 1 year) and -0.16 mm (baseline to 5 years). The changes for implant CH at 1 and 5 years of follow-up amounted 0.10 and 0.09 mm (BRA) and to 0.03 and 0.22 mm (STM). The changes in tissue thickness at 1 and 5 years in the BRA group amounted to -0.28 and -0.66 mm at 1 mm, -0.21 and -0.46 mm at 3 mm, and -0.32 and -0.45 mm at 5 mm, respectively. The changes in the STM group amounted to -0.15 and -0.54 mm at 1 mm, -0.24 and -0.48 mm at 3 mm, and -0.32 and -0.57 mm at 5 mm, respectively. No significantly different medians were observed. CONCLUSIONS: Minimal profilometric and linear changes occurred at implant sites between baseline and 5 years, between implant and tooth sites and between the two implant systems.

Effects of crown movement on periodontal biotype: a digital analysis.

Orthodontic treatment has important correlations with periodontal changes. Various mechanical and biological factors are involved in determining such changes, but anatomical and morphological variables, generally addressed as periodontal biotype, play a key role. In measurement of such modifications, digital and non-contact reverse engineering technologies may be of tremendous advantage. The aim of this study is to retrospectively evaluate, in a series of digitized dental casts, some of the parameters addressing periodontal biotype and correlate them to extent and direction of tooth movement. Pre- (T0) and post-treatment (T1) dental casts of 22 patients were scanned by 3Shape TRIOS 3® scanner. A number of variables (crown ratio, gingival margin position, gingival contour, papillae position, gingival scallop) were investigated and their variations calculated after digital measurements on single casts at T0 and T1, or after direct measurement (T1 vs T0) on the superimposition and alignment of digital models. Univariate and multivariate statistics were then performed. No significant correlation was detected between the sagittal or vertical movement of dental crown and displacement of the gingival margin. On the other hand, vestibular gingival contour resulted significantly altered by vestibular and extrusion movements. Further studies are needed to ascertain the differential effect of bone and soft tissue on such modifications. The relationship between orthodontic treatment and the periodontium overcomes the consideration of gingival recession and includes all the concepts of periodontal biotype with its characteristics. Digital technologies and non-contact reverse engineering techniques now available have the potential to allow a more precise definition of such a relationship.

Observation and determination of periodontal tissue profile using optical coherence tomography.

BACKGROUND AND OBJECTIVE: Diagnosis is a crucial step in periodontal treatment. The aim of this study was to evaluate the effectiveness of optical coherence tomography (OCT) for observation and determination of periodontal tissue profiles in vivo. MATERIAL AND METHODS: In experiment 1, refractive indices of purified water, porcine gingiva and human gingiva at 1330 nm were determined for the analysis of OCT images of periodontal tissues. In experiment 2, OCT examination was performed in the midlabial apico-coronal plane of mandibular anteriors in 30 Asian volunteers with healthy gingiva. Sulcus depth was measured on intra-oral photographs taken during probing. In the OCT images, the gingival, epithelial and connective tissue thickness, and the position of alveolar bone crest were determined and finally, the biologic width was measured. RESULTS: Refractive indices of purified water, porcine gingiva and human gingiva were 1.335, 1.393 and 1.397, respectively. Cross-sectional images of gingival epithelium, connective tissue and alveolar bone were depicted in real-time. The sulcular and junctional epithelium could be visualized occasionally. Laser penetration and reflection were limited to a certain depth with an approximate maximal imaging depth capability of 1.5 mm and OCT images of the periodontal structure were not clear in some cases. The average maximal thickness of gingiva and epithelium and biologic width at the mandibular anteriors were 1.06 ± 0.21, 0.49 ± 0.15 and 2.09 ± 0.60 mm, respectively. CONCLUSION: OCT has promise for non-invasive observation of the periodontal tissue profile in detail and measurement of internal periodontal structures including biologic width in the anterior region.

An Evaluation of the Effect of Periodontal Biotype on Inter-Dental Papilla Proportions, Distances Between Facial and Palatal Papillae in the Maxillary Anterior Dentition.

PURPOSE: Gingival esthetics are an essential segment of facial beauty. The aim of the present study was to clinically assess the impact of periodontal biotype (PB), the length between the base of interproximal contact area and the interproximal bone crest (CP-BC), the distance between the facial and palatal papillae (DFPP), and papillary proportions (PP) on the presence of interdental papillae (PIP). MATERIALS AND METHODS: 80 patients aged 18 to 60 years were recruited for study. PB and CP-BC were evaluated clinically. Alginate impressions of maxillary arches were made, and DFPPs were measured using a digital Vernier caliper. The impressions were later poured in dental stone, and PP were calculated. RESULTS: Descriptive statistics and ANOVA were used for statistical analysis for correlation among the variables. A greater proportion of individuals who had a thick PB (77.7%) had significantly higher amounts of PIP than did patients with thin PB (60.7%) (p < 0.01). A strong significant positive correlation was found between PIP in thick PB patients and DFPP (p < 0.01, r = 0.56); DFPP and PP (p < 0.01, r = 0.61). A strong negative correlation was seen between PIP in thin PB and DFPP (p < 0.01, r = -0.67). CONCLUSION: According to the results of this study, PB affected the heights and presence of maxillary interdental papillae by affecting papilla proportion and distances between the facial and palatal papillae.

The relationship between open versus normal contact point and inter-proximal papilla dimensions in periodontally healthy young adults: A controlled clinical trial.

AIM: The gingival architecture is determined by the spatial orientation of the gingival zenith (GZ) and the inter-dental papillae (IP). Among the factors commonly associated with the presence and morphology of the IP, the contact point (CP) and the inter-dental distance relationships have been considered the most important. The objective of the present controlled clinical trial was to evaluate the role of the CP in determining the clinical and morphometric parameters of the inter-dental papilla. MATERIALS AND METHODS: The inter-dental papillae of sixty patients with unilateral diastemas were evaluated by means of periodontal probing, transgingival probing, the papilla presence index and morphometric measurement with a digital calliper and were analysed with a paired t-test, with significance set at alpha value of 0.05 or lower. RESULTS: All the papillae exhibited PPI score = 1. Papillary measurements were significantly increased in the experimental (diastema) group. CONCLUSIONS: In patients with gingival health, the dimensions of the IP are significantly increased in teeth without a contact point in comparison with their contra-lateral controls with a contact point. The contact point does not determine the presence and size of the inter-dental papilla, in patients with a healthy gingiva and without periodontal attachment loss.

Impaired periodontium and temporomandibular joints in tumour necrosis factor-α transgenic mice.

AIM: Tumour necrosis factor (TNF)-α is a pathological factor causing the characteristic symptoms of periodontal disease and rheumatoid arthritis. In this study, we describe the phenotypes of human TNF-α transgenic mice (hTNFtg) with respect to their periodontium and the temporomandibular joint (TMJ). MATERIAL AND METHODS: Periodontal structures, TMJ and skull shape of hTNFtg mice and wild-type (WT) littermates were assessed by microcomputed tomography, automated segmentation, geometric morphometrics and histologic ground sections. RESULTS: We show that hTNFtg mice have an eroded lamina dura and reduced periodontal ligament space compared to (WT) littermates. Transgenic mice further exhibit severe destruction of the TMJ. Geometric morphometrics revealed that hTNFtg mice have a more laterally positioned TMJ with a concomitantly enlarged zygomatic process. Mandibular and maxillary teeth occluded properly. CONCLUSIONS: Our findings suggest that chronic inflammation in hTNFtg mice causes destructive changes of the periodontium and the TMJ.

Relationship Between Clinical and Histologic Periodontal Biotypes in Humans.

Histologic and histomorphometric evaluations of gingival biopsy samples of patients presenting either a thick or a thin gingival biotype were performed. Full-thickness gingival biopsy samples were obtained and processed for histologic and histometric evaluations. Thickness of the keratinized mucosa or gingiva was found to be increased in the thick biotype. Specifically, the connective tissue layer was thicker with no change in epithelial thickness. In conclusion, gingival transparency appears to be an adequate, clinically useful method to classify the gingival biotype. The thin gingival biotype is manifested by reduced connective tissue thickness; therefore, biotype conversion or enhancement may be based on augmentation of the connective tissue portion of the gingival tissues.

Evaluation of Periodontal Changes Adjacent to Extraction Sites during Upper Canine Retraction.

INTRODUCTION: There is an intimate relationship between orthodontic therapy and the periodontal changes that occur during tooth movement. MATERIALS AND METHODS: This prospective clinical trial aims at investigating the movement of both the free and attached gingiva, as well as the movement of the alveolar bone in the extraction site of the upper 1st premolars during the retraction of the upper canines. In this study, 17 patients (10 female, 7 male) requiring 1st premolar extraction before orthodontic tooth movement were selected and treated at the Department of Orthodontics in the Faculty of Dentistry in University of Hama, Hama, Syria. The upper 1st premolars were extracted, and the implant AutoTacs were applied on the alveolar bone afterward. Then, measurements between the center of the implant AutoTacs and the L-shape wire were taken, utilizing digital Vernier caliper. After 3 weeks of extraction, tattooing marked points were placed on the free and the attached gingival, and the measurements were taken using the same digital Vernier caliper. Closed coil springs made of nickel-titanium were used to retract the upper canines, and a force of 150 gm was applied. RESULTS: The results of this study showed significant differences between the movement of both the free and attached gingiva and the movement of the corresponding upper canines (p < 0.001). The movement of the free gingiva had formed about 77% of the amount of the movement of the upper canine retraction. No significant differences were detected between the place of implant AutoTac X1 and the L-shaped wire (W) during the retraction of the upper canine. On the contrary, significant differences were noticed between the place of implant AutoTac X2 and the L-shaped wire (W) during the retraction of the upper canine (p < 0.001). CONCLUSION: There is significant movement of hard and soft tissues during and after premolar extraction and orthodontic therapy. CLINICAL SIGNIFICANCE: The movement of supporting tissues of the teeth along with the alveolar bone during canine retraction is an important biological characteristic of the orthodontic tooth movement. Clinicians need to understand the role and importance of the supporting tissues during orthodontic treatment, which needs to be incorporated into their routine clinical evaluations.

Development and capture of soft tissue contours at time of implant placement.

A technique is described which will generate a customized healing abutment for a dental implant to allow the development of ideal soft tissue contours. With implant position and soft tissue contours defined at surgery, customized impression techniques can be used to capture those details and help generate the definitive implant-supported restoration. This workflow reduces the number of patient visits.

Effect of the Keratinized Mucosa Width on the Health Status of Periimplant and Contralateral Periodontal Tissues: A Cross-sectional Study.

INTRODUCTION: The purpose of this study was to examine whether the width of keratinized mucosa (WKM) is associated with the health status of tissue surrounding dental implants and the contralateral teeth. MATERIALS AND METHODS: Sixty patients who received implant-fixed unilateral prostheses in the premolar or molar region were recruited for the study. The following parameters were measured for each implant and contralateral tooth: WKM, gingival index (GI), probing pocket depth (PPD), bleeding on probing (BOP), pus discharge, plaque accumulation (PA), gingival recession (GR), and difficulty of brushing. The effect of the WKM on the health status of the surrounding tissue was evaluated by comparing the different WKM groups (WKM < 2 mm vs WKM ≥ 2 mm). RESULTS: Implants with a WKM <2 mm demonstrated significantly greater PPD, PA, and a higher rate of BOP compared with implants with a WKM ≥2 mm. There was significantly greater GR in contralateral teeth with a WKM <2 mm compared with a WKM ≥2 mm. In addition, implant sites had a higher rate of BOP compared with the contralateral teeth. CONCLUSIONS: Inadequate keratinized mucosa decreased cleansibility of implant sites and increased mucosal inflammation. There is a possibility that PA in implant sites caused more pronounced inflammatory response compared to contralateral tooth.

[Failure in anterior rehabilitation of agenesic maxillary lateral incisors]. / Échec dans la réhabilitation antérieure en cas d'agénésies des incisives latérales maxillaires.

Agenesis of the maxillary lateral incisors poses particular problems for dentists, orthodontists and patients. Treatment of these ageneses is still highly controversial, both functionally and esthetically. The patient's smile and anterior guidance are affected and must be restored. The diagnosis is easy. Few mistakes are possible. However, managing patients with missing maxillary lateral incisors can be a challenge, commonly involving two possible treatment approaches: space opening to replace the missing lateral incisor with a prosthetic unit (denture, bridge or implant) or orthodontic space closure replacing the missing lateral incisor with the maxillary canine camouflaged to mimic the appearance of a lateral incisor. One of these two options will be adopted using multiple means...liable to trigger a multitude of possible errors. Ultimately, optimal results can only be achieved if there is excellent coordination between different practitioners in various specialties. Each clinician will have a specific role to play. Also, the patient and family are at the heart of the decision-making process, by virtue of their consent (treatment duration, financial resources) and their motivation. This multi-factorial, multi-disciplinary decision process means that treatment of the lateral incisor is an ongoing challenge for the clinician striving for the best possible result. Each case is different. No set rules exist. No single factor can be neglected if we are to avoid "failure".