Parafunctional Habits and Periodontal Concerns

• Local predisposing factors are conditions or habits increasing susceptibility to periodontal diseases.
• These factors contribute to the disease process initiated by bacterial dental plaque, rather than initiating gingivitis or periodontitis themselves.
• They act through mechanisms that increase plaque retention, enhance pathogenic organism growth, and directly damage gingival and periodontal tissues.

Local Predisposing Factors:

• Calculus
• Iatrogenic factors
• Malocclusion
• Anatomic variations of teeth and soft tissues
• Periodontal complications from orthodontic therapy
• Effect of hypofunction and unreplaced missing teeth
• Food impaction and retention
• Habits
• Chemical and thermal irritation
• Mouth breathing

Iatrogenic Factors:

• Deficiencies in dental restorations or prostheses quality contribute to gingival inflammation and periodontal destruction.
• Inadequate dental procedures leading to periodontal tissue destruction is defined as iatrogenic factors.
• Important characteristics of dental restorations for periodontal health are the location of the gingival margin, contour, occlusion, materials, and removable partial denture design.
• Overhanging margins of dental restorations contribute to periodontal disease development by altering gingival sulcus ecology to favor gram-negative anaerobic microorganisms and inhibiting plaque control.
• Subgingival margins leads to subgingival roughness, severe gingivitis, and deeper periodontal pockets.
• Margins at the gingival crest induce less inflammation. Placement of supragingival margins is associated with periodontal health similar to nonrestored surfaces.
• Over-contoured crowns accumulate plaque and prevent self-cleansing mechanisms.
• Flat buccal and lingual contours that follow the root surface are more compatible with periodontal health.
• Restorations failing to establish adequate interproximal embrasure spaces are associated with papillary inflammation and recession of interdental papilla.
• The contour of the occlusal surface, defined by marginal ridges, and the location of the contact area help prevent food impaction.
• After removable partial dentures insertion, tooth mobility, gingival inflammation, and periodontal pocket formation may increase because they favor plaque accumulation
• Removable partial dentures can alter plaque composition promoting spirochetes increase.
• Restorative materials are generally not injurious to periodontal tissues, except self-curing acrylic resin.
• Variations exists in the ability of restorative material surface textures to retain plaque.
• All materials can be cleaned if polished and accessible for oral hygiene.
• Dental procedures can damage gingival tissues and cause gingival recession, such as tooth preparation, rubber dam placement, and gingival retraction.

Malocclusion:

• Irregular alignment of teeth or crowding enhances bacterial plaque retention.
• It makes plaque control more difficult.
• A relationship between crowding and periodontal disease has not been established between all investigators.

Anatomic Variations of Soft Tissue and Teeth:

• Prominent roots of teeth in buccal or lingual versions often lack bone coverage coronally, causing dehiscence or fenestration and frequently exhibiting gingival recession.
• Cervical enamel projections (CEPs) primarily occur on molars, where amelogenesis has failed near the root.
• CEPs appear as narrow, wedge-shaped enamel extensions towards the furcation area and are more common on buccal surfaces mostly on mandibular second molars.
• They are plaque retentive and predispose to attachment loss in furcation areas.
• Enamel pearls are ectopic enamel deposits of various shapes on root surfaces, and are frequently associated with furcation areas of maxillary molars.
• Enamel pearls complicate scaling and root planing, affect plaque removal, and can predispose to gingivitis and periodontitis.
• Palatogingival grooves often begin at the cingulum of maxillary lateral and central incisors and extend onto the root.
• Extension of the groove predisposes to plaque retention, leading to gingival inflammation, attachment loss, bone loss, and pocket formation.
• A frenum is a mucous membrane fold with muscle fibers attaching lips/cheeks to alveolar mucosa/gingiva.
• Problems occur when frenum attachment is too close to the marginal gingiva as the tension can pull the gingival margin away from the tooth.
• Abnormal frenum attachment is conducive to plaque accumulation and prevents proper brushing, which may lead to gingival recession, especially with minimal attached gingiva.

Periodontal Complications Associated with Orthodontic Therapy:

• Orthodontic therapy can affect the periodontium by increasing plaque retention, directly injuring the gingiva with overextended bands.
• Excessive forces can also lead to unfavorable forces affecting the tooth and supporting structures.

Plaque Retention and Composition:

• Orthodontic appliances increases anaerobic gram-negative bacteria proportions, such as Prevotella intermedia, Prevotella melaninogenica, and Actinobacillus actinomycetemcomitans.

Gingival Trauma:

• Orthodontic bands should not be forcefully placed beyond the epithelial attachment, because it detaches the gingiva from the tooth.
• This results in apical proliferation of the junctional epithelium, increasing gingival recession incidence.

Tissue Response to Orthodontic Forces:

• Alveolar bone is remodeled by osteoclasts resorbing bone in pressure areas and osteoblasts forming bone in tension areas to permit tooth movement.
• Moderate orthodontic forces usually result in bone remodeling and repair.
• Excessive orthodontic forces can cause necrosis of the periodontal ligament and adjacent alveolar bone, increasing apical root resorption risk.

Effects of Insufficient Occlusal Force (Hypofunction):

• Reduced occlusal force can be harmful to supporting periodontal tissues because the periodontium relies on function-provided stimulation to preserve its structure.
• Insufficient stimulation leads to cancellous bone trabeculae reduction in number and thickness.
• The periodontal ligament atrophies.
• Hypofunction results from conditions like open-bite relationships, absence of functional antagonists, and unilateral chewing habits.

Unreplaced Missing Teeth:

• Failure to replace missing posterior teeth can harm the support of remaining teeth.
• Initial changes include mesial drifting of adjacent teeth, over-eruption of opposing teeth, open contacts, plaque retention, food impaction, gingival inflammation, and bone resorption.

Food Impaction and Food Retention:

• Food impaction is forceful wedging of food into the periodontium, leading to gingival trauma, inflammation, attachment loss, and bone loss.
• Food retention is lateral pressure pushing food interproximally into wide embrasure spaces by lips, cheeks, or tongue.

Mechanism of food impaction:

• Opening of interproximal contact areas due to tooth structure loss or improperly constructed restorations.
• Flattened convex proximal surfaces due to tooth wear increases the wedging effect of opposing cusps.
• Plunger cusps that wedge food forcibly affect interproximal embrasures.
• Excessive anterior overbite is a common cause of food impaction.

Signs and Symptoms of Food Impaction:

• Gingival inflammation with bleeding and altered taste in the affected area
• Gingival recession
• Loss of attachment and alveolar bone resorption
• Periodontal abscess formation
• Pressure sensation
• Vague pain

Parafunctional Habits:

• Parafunctional Habits can cause direct injury to gingival and periodontal tissues.
• Some habits include tooth to tooth contact as bruxism tapping and clenching as well as contact between teeth and oral musculature as lip biting cheek biting, tongue thrusting.
• Psychological stress is associated with the parafunctional habits.

Bruxism:

• Involuntary unconscious and excessive grinding, tapping or clenching of teeth during sleep or while awake.
• In grinding and tapping this is forceful contact that involves mandibular movement.
• During bruxism muscle activity generate forces of high magnitude which can damage the teeth, the supporting periodontal structures as well as the tempromandibular joints.
• Normal functional activities protecting the dental structures from damage are less efficient in controlling muscle activity.

Causes of bruxism:

• Nervous tension
• Occlusal interference

Effects of bruxism:

• On teeth, wear facets, mobility and pulpal pain in severe cases.
• On PDL, lesion of occlusal trauma or widening with increased tooth mobility.
• On muscles of mastication, hypertrophy or tender muscles.
• On TMJ, crepitus, clicking eventually leads to joint arthritis.

Diagnosis of bruxism:

• Advanced attrition of the occlusal surfaces wear facets
• Increased tooth mobility
• Widened PDL space in radiographs
• Hypertonicity of muscles of mastication
• TMJ discomfort

Tongue Thrusting:

• Tongue thrusting is forceful wedging of the tongue against the teeth.
• Several factors may cause tongue thrusting such as digit sucking, allergies, large tonsills and abnormally large tongue.
• Nervous thrusting also pushes the tongue against the teeth while at rest.
• Pressure from the tongue may cause drifting.

Toothbrush Trauma:

• A new or hard toothbrush can abrade the epithelium leaving shallow ulcerations, leading to gingival recession and exposure of the root
• Improper use of dental floss toothpicks may result in lacerations of the interdental papilla.

Chemical Irritation:

• Acute gingival inflammation with ulceration may be caused by direct injury of chemicals.
• Acute gingival inflammation may represent allergy or sensitivity reactions to components in mouthwashes, toothpastes or denture base materials.

Mouth Breathing:

• Mouth breathing is often associated with gingival inflammation causing surface dehydration and irritation leading to inflammation.
• The gingival changes include erythema, edema, mild gingival enlargement .