Gingival and Dentogingival Junctional Tissue

Stillman Cleft

A cleft-like area of gingival recession, related to occlusal trauma.

Junctional Epithelium

A deeper extension of the sulcular epithelium, lines the floor of the gingival sulcus and is attached to the tooth surface. It is attached to the tooth surface by way of an epithelial attachment (EA). The JE surrounds the tooth like a turtle neck with a cross-section resembling a thin wedge.

Earlier Gingival Grafting Procedures

A gingival graft is a generic name for any of a number of surgical periodontal procedures who's combined aim is to cover an area of exposed tooth root surface with grafter oral tissue. When a graft procedure is preformed to reduce the amount of gingival recession on the root, keratinization is taken into consideration because the goal of grafting is to increase the amount of attached keratinized tissue. When a graft procedure is preformed to reduce the amount of gingival recession on the root, keratinization is taken into consideration because the goal of grafting is to increase the amount of attached keratinized tissue. Earlier grafting procedures included free gingival graft (FGG) and lateral pedicle graft (LPG)

Electron Micrographs of Junctional Epithelium and its epithelial attachment.

A) attachment of the junctional epithelium (JE) to the enamel surface (ES, Enamel space) at the internal basal lamina (IBL) and to the connective tissue (CT) of the lamina propria by the external basal lamina (EBL). Note its wide intercellular spaces and the lack of cellular differentiation of the layers of epithelium that would denote maturation.

Gummy Smile

An excessive display of maxillary facial gingival tissue are not ideal, such as when the maxillary central incisors and canines barely touch the lip line or border of the upper lip.

Periodontal Disease

An inflammatory disease that affects the soft and hard structures that support the teeth. In its early stage, it is considered gingivitis, and in its later stages, periodontitis. With active periodontal disease, both the marginal gingiva and attached gingiva can become enlarged, especially the interdental papillae. This spongy enlargement results from edema occurring in the lamina propria of the tissue caused by the inflammatory response.

Gingival Biotype

Another consideration which is also known as the periodontal phenotype. It is the thickness of the gingiva within the faciolingual dimension. According to studies, individuals with a gingival biotype that includes thin scalloped gingiva demonstrated a greater prevalence of recession, which was then correlated with a thinner underlying bone.

Gingival Hyperplasia

Another type of gingival enlargement, can affect both the epithelium and the lamina propria, causing a permanent fibrous enlargement with the gingival margin becoming more coronal.

Gingival Tissue Anatomy Contined

Apical to the contact area, the interdental gingiva assumes a nonviable concave shape between the facial and lingual gingival surfaces forming the gingival col. The col varies in depth and width, depending on the expanse of the contacting tooth surfaces. The attached gingiva is considered a masticatory mucosa. Healthy attached gingiva is pink in color with some areas of melanin pigmentation possible. The tissue when dried it is dull firm immobile tissue, with varying amounts of stippling.

DEJ Tissue Development

Before the eruption of the tooth and after enamel maturation, the ameloblasts secrete a basal lamina on the tooth surface that serves as a part of the primary epithelial attachment (EA). As the tooth actively erupts, the coronal part of the fused consisting of reduced enamel epithelium (REE) and surrounding oral epithelium peels back off the crown. The ameloblasts also develop hemidesmosomes for the primary EA and become firmly attached to the enamel surface. However, the cervical part of the fused tissue remains attached to the beck of the tooth by the primary EA. This fused tissue, which remains near the CEJ after the tooth erupts, serves as the initial JE of the tooth, creating the first tissue attached to the tooth surface. This tissue is later replaced by a definitive junctional epithelium (JE) as the root is formed.

BOP

Bleeding on probing even with a gentle touch, beings to occur even with early signs of gingivitis present. This is due to the periodontal probe damaging the increased blood vessels in the capillary plexus of the lamina propria, which are now closer to the surface because of the ulceration of the JE.

Subepithelial Connective Tissue Gingival Graft

Consists of only lamina propria that is taken from the surrounding keratinized attached gingiva and then grafted directly to the root. These types of grafting are considered passive mucogingival repair procedures. In contrast, active tissue engineering for mucogingival repair now looks very promising for the future as it produces 3 dimensional models of the oral mucosa that may soon be applied to actual patient care.

DGJ Tissue Properties

The DGJ is the junction between the tooth surface and the gingival tissue. The sulcular epithelium and junctional epithelium together form the DGJ tissue.

Microscopic look at sulcular epithelium

Consists of stratified squamous epithelium similar to the deeper epithelium of the attached gingiva and adjacent outer marginal gingiva, making it a transition tissue between the gingival epithelium and JE. Apically, it overlaps the coronal border of the JE, a structural design that minimizes ulceration of the epithelial lining in this region. The thinner SE is nonkeratinized, unlike the keratinized marginal gingiva and attached gingiva. In addition, the interface between the SE and the lamina propria that it shares with the outer gingival tissue is relatively smooth compared to the strongly interdigitated interface of the outer gingival tissue. The deeper interface between the JE and the underlying lamina propria is also relatively smooth, without rete ridges or connective tissue papillae.

Gingivitis Cont

Dental professionals should consider gingivitis the "Line in the sand" beyond which no patient should step. Failure to intervene at this early point will result in some patients progressing to periodontitis, which is incurable and condemns one to a lifetime of complex disease management. Basic dental care should be aimed primarily at reduction of etiologic factors to reduce or eliminate inflammation, thereby allowing the gingival tissue to heal. Over time, appropriate modalities that include home care and professional care is important in preventing reinitiation of inflammation.

Dental Perioscopy Evaluation

Endoscopic evaluation of the periodontal pocket is also becoming increasingly available in dental settings outside of the research facilities; it can facilitate subgingival visual exams without reliance on tactile sense and without surgical flap access. Techniques for identification and interpretation of the hard and soft tissue images, as well as the location of root fractures or deposits, defective restorations, and caries, are being developed.

Periodontal Pocket: Charting

For a periodontal chart, the clinician measures and records pocket depths surrounding the teeth. In a healthy mouth, each toot is surrounded by a free collar of marginal gingiva. At a depth of 0 to 3 mm, the gingiva is attached to the cementum, the surface of the tooth root. The surrounding 0 to 3 mm space within the free color is referred to as the sulcus. In an unhealthy condition, sulcus depths can be much greater because of loss of attachment; these are referred to as periodontal pockets. Measurement is accomplished with a calibrated periodontal probe inserted into the sulcus parallel to the long axis of the tooth. Depending on design, the probe may be marked at each millimeter up to 10 mm. A more common design has the markings at 4mm and 6mm deleted for easier reading. Color coded probes may be marked in blocks with a green block up to 3mm (indicating a healthy condition) and a red block up to 6mm (indicating an unhealthy condition and the presence of periodontal disease).

Gingival Tissue Properties

Gingival tissue in the oral cavity is the most important tissue of the orofacial region for dental professionals to know and understand, and the most challenging as well. All of the periodontal therapy initiated and home care instructions given are for the purpose of creating a healthy environment for the gingival tissue. Even with restorative treatment of the teeth, the impact on the gingival tissue must be considered to ensure the restoration's longevity.

Periodontal Therapy Evaluation

Given that the turnover time of the JE is approximately 1 week ( unlike most oral tissue that have slower turnover times), evaluation of periodontal therapy must occur after this time to allow initial healing of the area. Therefore, follow-up scheduling of patients should occur after this biologic temporal factor of turnover time.

DGJ Tissue Turnvoer

In both the sulcular epithelium (SE) and epithelium of the marginal gingiva, the turnover process insuring the regeneration of the tissue occurs in a manner similar to that of the epithelium of the attached gingiva; the basal cells migrate superficially after mitosis, undergo maturation, and take the place of the superficial cells, which are shed in the oral cavity as they die. In the JE, even thought it does not undergo cellular maturation, its basal cells still migrate superficially upon dividing and continuously replace the dying supra basal cells that are desquamated into the gingival sulcus at a fast pace. The migratory route of the cells as turnover takes place in the JE is in a coronal direction, parallel to the tooth surface. Most interestingly, the JE has the fastest turnover time in the entire oral cavity, which is approximately 4 to 6 days.

Implant DGJ Tissue

In regard to newly placed implants, the superior tissue present originates only from epithelial cells of the oral mucosa, as opposed to the JE located around natural teeth, which originates also from the REE. Structurally, the periimplat tissue closely resembles a long JE.

Gingival Crevicular Fluid

Is from the adjacent blood supply in the lamina propria. The usually GCF flow rate is quite slow, calculated at 1 to 2 microliters per tooth per hour. Thus, the amount of GCF is minimal at one time in the healthy state. The GCF from the lamina propria seeps between the epithelial cells and then into the gingival sulcus. This fluid allows the components of the blood system to reach the tooth surface through the junctional epithelium from the blood vessels of the adjacent lamina propria.

Dentogingival Junction Tissue Histology

It has hemidesmosomal intercellular junctions, which involve the attachment of cells to an adjacent noncellular surface (the tooth). Note the smaller attachment plaques of the hemidesmosomal junction and tontofilaments on the cellular side. Cell adhesion to the noncellular surface is edited by transmembrane protein. The deepest layer of the JE or basal layer undergoes constant and rapid cell division or mitosis. This proliferative cell layer is in contact with the lamina propria of the nearby gingiva by way of the external basal lamina. This process allows a constant coronal migration of the cells as they die and are shed into the floor of the gingival sulcus at the coronal end of the JE.

Lazer Periodontal Therapy

Laser is an acronym for light amplification by stimulated emission fo radiation and functions by transmitting light energy to tissues. It is a collimated, focused monochromatic ray of light. The energy beam reacts with a target material by being absorbed, reflected, or scattered. A target tissue absorbs the light. If it is well absorbed, the energy virtually explodes the cell ( and extracellular matrix) in a process called ablation. The efficiency of ablation is related to the wavelength and the affinity of the target tissue. If the wavelength is not well absorbed, there is scattering and a thermal reaction occurs with carbonization, charring, and melting. The clinician must understand how this energy is affecting the target tissue and the adjacent tissue as well.

Laser Periodontal Therapy Continued

Lasers are currently available for clinical use to incise soft and hard tissue during surgical periodontal therapy, such as crown lengthening. Many new technologies are being proposed for periodontal procedures. Most technologies, including the laser, are meant to replace curettes, scalpels, and other instruments used in traditional periodontal therapy. In periodontics, lasers have potential application in 3 areas: Surgical procedures such as gingivectomy and osseous crown lengthening. Scaling and root planning Management of pathologic changes resulting from periodontal disease. Laser-mediated periodontal therapy is now being used for nonsurgical subgingival curettage to significantly decrease subgingival pathogenic bacteria. Lasers are currently viewed by some as an adjunct in periodontal therapy for removal of soft tissue within the periodontal pocket.

Increased levels of Gingival Crevicular Fluid

Periodontal inflammation is also accompanied by an increase in the amount of GCF in order to fight the microbial attack, either of serous (Clear) or suppurative nature, distending the already enlarged tissue even further. Thus, relatively large amounts of fluid now pass through the more permeable epithelial wall. This is noted clinically only when it involves the visible whiter suppuration, or pus, resulting from the presence of cellular debris and extensive populations of PMNs.

Periodontal Support Measurements

Periodontal probing continues to be a key element in the diagnosis of periodontal disease and its depth must be recorded in the patient's chart to monitor periodontal disease. However, a probing depth alone does not reveal the complete state of health of the area being measured. Another measurement of the extent of the periodontal support it the clinical attachment level (CAL). This is the measurement of the positIon of the gingiva in relation to the CEJ, which is a fixed point that does not change throughout life. However, this clinical attachment level is not the same as the clinical attachment loss, which is considered the true attachment loss based on histology related to CAL. If clinical attachment loss is defined as the extent of the periodontal support that has been destroyed around a tooth, then in a healthy situation the probe reading would be 0 mm. But this situation never occurs since the tip of the probe always penetrates into the gingival tissue that is internal to the sulcus.

Dentogingival Junctional Tissue Histology:Photomicrograph

Photomicrograph of the initial junctional epithelium before eruption (arrows) overlying the enamel (E, enamel space), note the CEJ (J), the cementum (C), and dentin (D). Deep to the junctional epithelium is the interconnecting connective tissue (CT) of both the lamina propria and adjacent periodontal ligament.

Charting

Probes are designed with blunt or ball-tipped ends to avoid puncturing the junctional epithelium at the base of the sulcus during probing. Assisted probes are also available that record pocket depths automatically on a computerized chart. For a full periodontal chart, 6 readings are taken on each tooth and recorded in 6 boxes above and below the teeth on the chart. Beginning with tooth number one, a measurement is taken at the MB line angle, the midbuccal, the DB line angle, the DL line angle, the midlingal and the ML line angle. The probe can be "walked" around the circumference of the tooth for complete exploration.

Gingival Recession

Results in the gingival margin becoming more apical. This change in the gingival margin can result from periodontal disease, tooth position, abrasion by incorrect toothbrushing methods, abfraction from occlusal stresses ( such as parafunctional habits), thin. scalloped gingival biotype, and aging process, as well as tight frenal attachments. The width of the attached gingiva may also decrease with periodontal disease, reducing the underlying support for the tooth, and should be recorded in the patient's chart as well as should any changes present in the gingival tissue.

Free Gingival Groove

Separates the attached gingiva from the marginal gingiva. This slight depression on the outer surface of the gingiva does correspond not to the depth of the gingival sulcus but instead to the apical border of the Junctional epithelium.

Attached Gingiva and the Marginal Gingiva

Share similar histology because both are considered masticatory mucosa; however, each has histologic features specific to the tissue. The attached gingiva has an overlying thick layer of mostly parakeratinized stratified squamous epithelium which obscures its extensive vascular supply in the underlying lamina propria, making the tissue appear pinkish instead of the vascularized reddish or bluish. The lamina propria also has tall narrow connective tissue papillae alternating with the rete ridges, giving the tissue its varying amounts of stippling. Thus the interface between the epithelium and lamina propria is highly interdigitated for the attached gingiva. The lamina propria is directly attached to the underlying boy jaws, making the attached gingiva firm and immobile. The lamina propria thus serves as a mucoepriosteum along with the periosteum of the alveolar process. In contrast, the marginal gingival has an overlying surface layer of only orthokeratinized stratified squamous epithelium. The associated underlying lamina propria also has tall narrow papillae, but this lamina propria is continuous with the lamina propria of the gingival tissue that faces the tooth.

Gingival Apex of the Contour

Since gingival contours form a silhouette around the cervical section of a tooth, this fact should be acknowledged when considering overall esthetics of smile design. The cervical peak of the individual gingival contour is referred to as the gingival apex of the contour.

Microscopic view of JE

The JE cells are loosely packed, with fewer intercellular junctions using desmosomes between cells, as compared with other types of gingival tissue. The number of intercellular spaces between the epithelial cells of the JE is also at a higher level than other types of gingival tissue and all are filled with tissue fluid. Overall the JE is more permeable than other gingival tissue due to its lower density of desmosomal junctions and increased intercellular spaces between the cells of the JE. The increased permeability allows for emigration of large numbers of mobile WBCs from the blood vessels in the deeper lamina propria into the JE, even in healthy tissue. This mostly involves the polymorphonuclear leukocytes (PMNs), with those cells actively undergoing phagocytosis. In the absence of clinical signs of inflammation, approximately 30.000 PMNs migrate per minute through the JE into the oral cavity. The increased presence of these WBCs may keep the tissue healthy by protecting it from microorganisms within the dental biofilm and also associated toxins that continually form on the exposed tooth surface in the vicinity. In addition, the JE is also thinner than then SE, ranging coronally from only 15 30 cells thick at the floor of the gingival sulcus, and then tapering to a final thickness of 3 to 4 cells at its apical part.

Clinical Considerations for Gingival Tissue: Biologic Width

The biologic width or supracrestal tissue attachment describes the combined heights of the suprabony soft tissue, which is attached to the part of the tooth coronal to the crest of the alveolar bone. Thus the biologic width is comprised of the healthy supracrestal lamina propria and the epithelial attachment of the junctional epithelium to the root surface ( and crown if not fully erupted). Based on studies, the biologic width is commonly stated to be 2.04mm , which represents the sum of the epithelial attachment of the junctional epithelium and lamina propria measurements. (photo shows histologic sulcus depth 0.69mm length of the epithelial attachment of the JE (0.97mm) lamina propria attachment length (1.07mm) biologic width (2.4mm from adding both attachment length measurements)

DGJ Tissue Histology

The fewer layers present in the JE, from its basal layer to the supra basal layer, do not show any change in cellular structure related to maturation, unlike other types of gingival tissue. Therefore, the JE does not mature like keratinized tissue, such as the marginal gingiva or attached gingiva, which fills its matured superficial cells with keratin. Nor does JE have cells like nonkeratinized tissue of the sulcular gingiva and throughout the rest of the oral cavity that enlarge and migrate superficially. Thus the JE cells do not mature and form into either a granular layer or intermediate layer. The JE cells have many organelles in their cytoplasm such as rough endoplasmic reticulum, Golgi complex, and mitochondria, indicating a high metabolic activity. However, even with that heightened state, the JE cells remain immature or undifferentiated until they die and are shed or lost in the gingival sulcus.

Smile Design

The gingival contour is also related to its position in regard to the lip line with continued consideration of smile design. The optimal smile line clinical appearance should reveal the least amount of maxillary facial gingival tissue as possible under the lip line.

Gingival Tissue Anatomy

The gingival tissue that tightly adheres to the bone around the roots of the teeth is the attached gingiva. The gingival tissue between adjacent teeth is an extension of attached gingiva and is the interdental gingiva, forming the interdental papillae.

External Basal Lamina

The internal basal lamina of the EA is also continuous with this; between the JE and the lamina propria at the apical extent of the JE. The EA is very strong in a healthy state, acting as a type of protective seal between the soft gingival tissue and the hard tooth surface. Thus the JE has 2 basal laminas, one that faces the tooth ( internal) and one that faces the lamina propria of the nearby gingiva (external).

McCall Festoon

The marginal gingiva can become extremely rolled. The lifesaver-shaped edema of the marginal gingiva is called McCall festoon.

Pathologic Tooth Migration

The overall tooth displacement that results when the balance among the factors that maintain physiologic tooth position is disturbed, may also be present due to a weakened periodontium. The occlusal forces need not be at an abnormal level the periodontal support is already reduced by periodontal disease.

Bleeding on Probing

The presence of bleeding is one of the first clinical signs of active periodontal disease in uncomplicated cases and should be recorded per individual tooth and tooth surface the patient's chart. However, in patients who used nicotine products, the gingival tissue rarely bleeds because of unknown factors that do not seem related to dental biofilm and calculus formation but to the incorporated nicotine that causes vasoconstriction, a narrowing of the blood vessels.

Biologic Width

The primary significance of biologic width to the clinician is its importance relative to the position of restorative margins and its impact on post surgical tissue position. Evaluation of biologic width can be made during probing of the area noting chronic progressive gingival inflammation, possibly along with gingival hyperplasia as well as clinical attachment loss around the restoration. Bone sounding under local anesthesia and radiographic interpretation (only of inter proximal violations) can also be used.

Periodontal Disease Classification Guidelines

The recent more precise staging and intuitive grading of periodontal disease guidelines by both the American Academy of Periodontology (AAP) and the European Federation of Periodontology (EFP) have started a new paradigm that includes factors for future risk analysis for the patient as well as the first-ever classifications for periimplat diseases and conditions.

Dentoging Junctional Tissue Properties

The slight depression of the free gingival groove on the outer surface th gingiva corresponds to the apical border of the inner JE and not to the depth of the gingival sulcus. Instead, the probing depth of the gingival sulcus is measured by the use of a calibrated periodontal probe. The depth of the healthy gingival sulcus varies from 0.5 to 3mm, with an average of 1.8mm. However, the clinical probing depth of the gingival sulcus may be considerably different from the true microscopic gingival sulcus depth. In a healthy-case scenario and taking a more microscopic perspective of what occurs with probing, one can note that the instrument is gently inserted, then slides right by the SE, and is finally stopped by the EA of the JE.

Dentogingival Junctional Tissue Properties

The sulcular epithelium (SE) or crevicular epithelium stands away from the tooth, creating a gingival sulcus. The gingival sulcus is filled with gingival crevicular fluid (GCF). The depth of the healthy gingival sulcus varies from 0.5 to 3mm with an average of 1.8mm.

Internal Basal Lamina

The suprabasal cells, which make up the most superficial layer of the JE, serve as part of the EA of the gingiva to the tooth surface. These more supra basal epithelial cells of the JE provide the hemidesmosomes and the internal basal lamina that create the EA because this is a cell-to-noncellular type of intercellular junction. Furthermore, because the structure of the EA is similar to that of the junction between the epithelium and subadjacent connective tissue, this internal basal lamina also consists of a lamina Lucida and lamina densa.

Gingival Tissue Anatomy Cont

The width of the attached gingiva is measured by the distance between the MGJ that remains stationary after the permanent dentition eruption and the projection on the external surface of the apex of the gingival sulcus. The width of the attached gingiva on the facial aspect varies according to its location and is an important clinical parameter of periodontal health. The attached gingiva has the greatest usually in width for the incisor region at 3.5 to 4.5 mm for the max arch and 3.3 to 3.9 mm for the man arch; in contrast; the narrowest is for the max posterior quadrants at 1.9mm and 1.8mm for mandibular first premolars At the gingival margin of each tooth is the marginal gingiva ( of free gingiva) , which is continuous with the attached gingiva.

Periodontitis Fig 10.12

True apical migration of EA also occurs with advanced periodontal disease, causing a deepened gingival sulcus, which is now considered a periodontal pocket, lined by pocket epithelium (PE) instead of dentogingival junctional tissue. The most prominent histologic characteristic of PE are the presence of ulceration and gingival hyperplasia with the formation of rete ridges and connective tissue papillae at the once smooth tissue interface.

Attached Gingiva Vs. Marginal Gingiva

Unlike the attached gingiva, the marginal gingiva is not attached to the underlying bony alveolar process, making this tissue firm but mobile. Further, the epithelium covering the col consists of the marginal gingiva of the adjacent teeth, except that in this small area it is nonkeratinized. The lack of keratinization of the Cole tissue may be important in the formation of periodontal disease along with its thinness and apically inclined form. It is important to note that the gingival fiber group is located in the lamina propria of the marginal gingiva.

Free Gingival Graft

Uses a thickness of both keratinized epithelium and lamina propria harvested from the hard palate and grafted to the root to form a new band of keratinized attached gingiva. This procedure generally is somewhat slightly successful, but the graft tends to be lighter colored, and studies show that the epithelium does not survive the procedure, which means that the donor site requires extra time to heal and allow migration of the surrounding epithelium to cover the site.

Marginal Gingiva

Varies in width from 0.5 to 2.0 mm from the free gingival crest to the attached gingiva. The marginal gingiva follows the scalloped pattern established by the contour of the CEJ of the teeth. When dried, the marginal tissue is similar in clinical appearance to the attached gingiva, including pinkness, dullness, and firmness because the marginal gingiva is also considered a masticatory mucosa. However, the marginal gingival lacks the presence of stippling, and the tissue is mobile or free from the underlying tooth surface, which can be demonstrated with a periodontal probe or blowing air into the gingival sulcus. In addition, the marginal gingiva is more translucent than the attached gingiva, so much so that the darker subgingival calculus and even the dark margins of poorly executed prosthetic crowns can show through if present.

DGJ Epithelium Pathology: Periodontitis

When the deeper tissue of the periodontium is affected by periodontal disease, further damage can occur, and the disease can become chronic in nature, this condition is now considered periodontitis. As the disease progresses apically, exposed furcations (areas between the roots) are now present around the posterior teeth, and the teeth become increasingly mobile.

Gingivitis

When these damaging agents can enter the JE, the gingival tissue undergoes the initial signs of active periodontal disease with gingivitis. This occurs due to the increased permeability of the JE allows emigration of the PMN type of WBC and also allows microorganisms from the dental biofilm and associated toxins from the exposed tooth surface to enter this tissue from the deeper lamina propria. These signs of gingivitis include acute or even chronic inflammation with the formation of edema as well as an increased number of WBCs and epithelial ulceration with tissue thinning. The ulceration of the JE allows even more damaging agents to enter the deepest parts of the periodontium, thus progressing the disease toward the bony jaw. The process of gingivitis begins with the recognition of the invasion by microorganisms from the dental biofilm by the gingival epithelial cells. Embedded in the cell membrane of the gingival epithelial cells ( and many others including the skin and gastrointestinal tract) are toll-like receptors (TLRs)

Periodontopathogens

Within a periodontal pocket are believed to play an important role in periodontitis, such as aggregatibacter actinomycetamcomitans (Aa) or Porphyromanas gingival (Pg).

Periodontal Pocket: Abscess Formation

Without intervention, a periodontal pocket can become a localized infected fascial space and may result in an abscess formation with a papule appearing on the gingival surface.