NEET MDS Lessons
Pedodontics
Causes:
The primary cause of CP is any factor that leads to decreased oxygen supply
(hypoxia) to the developing brain. This can occur due to various reasons,
including complications during pregnancy, childbirth, or immediately after
birth.
Classification of Cerebral Palsy:
-
Based on Anatomical Involvement:
- Monoplegia: One limb is affected.
- Hemiplegia: One side of the body is affected.
- Paraplegia: Both legs are affected.
- Quadriplegia: All four limbs are affected.
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Based on Neuromuscular Involvement:
- Spasticity: Characterized by stiff and tight muscles; this is the most common type, seen in 70% of cases. Affected individuals may have limited head movement and a limp gait.
- Athetosis: Involves involuntary, writhing movements, seen in 15% of cases. Symptoms include excessive head movement and drooling.
- Ataxia: Affects balance and coordination, seen in 5% of cases. Individuals may exhibit a staggering gait and slow tremor-like movements.
- Mixed: A combination of more than one type of cerebral palsy, seen in about 10% of cases.
1. Spastic Cerebral Palsy (70% of cases)
Characteristics:
- Limited Head Movement: Individuals have restrictions in moving their head due to increased muscle tone.
- Involvement of Cerebral Cortex: Indicates that the motor control areas of the brain (especially those concerning voluntary movement) are affected.
- Limping Gait with Circumduction of the Affected Leg: When walking, the patient often swings the affected leg around instead of lifting it normally, due to spasticity.
- Hypertonicity of Facial Muscles: Increased muscle tension in the facial region, contributing to a fixed or tense facial expression.
- Unilateral or Bilateral Manifestations: Symptoms can occur on one side of the body (hemiplegia) or affect both sides (diplegia or quadriplegia).
- Slow Jaw Movement: Reduced speed in moving the jaw, potentially leading to functional difficulties.
- Hypertonic Orbicularis Oris Muscles: Increased muscle tone around the mouth, affecting lip closure and movement.
- Mouth Breathing (75%): The individual may breathe through their mouth due to poor control of oral musculature.
- Spastic Tongue Thrust: The tongue pushes forward excessively, which can disrupt swallowing and speech.
- Class II Division II Malocclusion (75%): Dental alignment issue often characterized by a deep overbite and anterior teeth that are retroclined, sometimes accompanied by a unilateral crossbite.
- Speech Involvement: Difficulties with speech articulation due to muscle coordination problems.
- Constricted Mandibular Arch: The lower jaw may have a narrower configuration, complicating dental alignment and oral function.
2. Athetoid Cerebral Palsy (15% of cases)
Characteristics:
- Excessive Head Movement: Involuntary, uncontrolled movements lead to difficulties maintaining a stable head position.
- Involvement of Basal Ganglia: Damage to this area affects muscle tone and coordination, leading to issues like chorea (involuntary movements).
- Bull Neck Appearance: The neck may appear thicker and less defined, owing to abnormal muscle development or tone.
- Lack of Head Balance, Drawn Back: The head may be held in a retracted position, affecting posture and balance.
- Quick Jaw Movement: Involuntary rapid movements can lead to difficulty with oral control.
- Hypotonic Orbicularis Oris Muscles: Reduced muscle tone around the mouth can lead to drooling and lack of control of oral secretions.
- Grimacing and Drooling: Facial expressions may be exaggerated or inappropriate due to muscle tone issues, and there may be problems with managing saliva.
- Continuous Mouth Breathing: Patients may consistently breathe through their mouths rather than their noses.
- Tissue Biting: Increased risk of self-biting due to lack of muscle control.
- Tongue Protruding: The tongue may frequently stick out, complicating speech and intake of food.
- High and Narrow Palatal Vault: Changes in the oral cavity structures can lead to functional difficulties.
- Class II Division I Malocclusion (90%): Characterized by a deep bite and anterior open bite.
- Speech Involvement: Affected due to uncontrolled muscle movements.
- Muscle of Deglutition Involvement: Difficulties with swallowing due to affected muscles.
- Bruxism: Involuntary grinding or clenching of teeth.
- Auditory Organs May be Involved: Hearing impairments can coexist.
3. Ataxic Cerebral Palsy (5% of cases)
Characteristics:
- Slow Tremor-like Head Movement: Unsteady, gradual movements of the head, indicative of coordination issues.
- Involvement of Cerebellum: The cerebellum, which regulates balance and motor control, is impacted.
- Lack of Balance Leading to Staggering Gait: Individuals may have difficulty maintaining equilibrium, leading to a wide-based and unsteady gait.
- Hypotonic Orbicularis Oris Muscles: Reduced muscle tone leading to difficulties with oral closure and control.
- Slow Jaw Movement: The jaw may move slower, affecting chewing and speech.
- Speech Involvement: Communication may be affected due to poor coordination of the speech muscles.
- Visual Organ May be Involved (Nystagmus): Involuntary eye movements may occur, affecting visual stability.
- Varied Type of Malocclusion: Dental alignment issues can vary widely in this population.
4. Mixed:
Mixed cerebral palsy involves a combination of the above types, where the
individual may exhibit spasticity, athetosis, and ataxia to varying degrees.
Dental Considerations for Mixed CP:
- Dental care for patients with mixed CP is highly individualized and depends on
the specific combination and severity of symptoms.
- The dentist must consider the unique challenges that arise from the
combination of muscle tone issues, coordination problems, and potential for
involvement of facial muscles.
- A multidisciplinary approach, including occupational therapy and speech
therapy, may be necessary to address oral function and hygiene.
- The use of sedation or general anesthesia might be considered for extensive
dental treatments due to the difficulty in managing the patient's movements and
ensuring safety during procedures.
Associated Symptoms:
Children with CP may exhibit persistent reflexes such as the asymmetric tonic
neck reflex, which can influence their dental treatment. Other symptoms may
include mental retardation, seizure disorders, speech difficulties, and joint
contractures.
Dental Problems:
Children with cerebral palsy often experience specific dental challenges:
- They may have a higher incidence of dental caries (tooth decay) due to difficulty in maintaining oral hygiene and dietary preferences.
- There is a greater likelihood of periodontal disease, often exacerbated by medications like phenytoin, which can lead to gum overgrowth and dental issues.
Dental Treatment Considerations:
When managing dental care for children with cerebral palsy, dentists need to
consider:
- Patient Stability: The child’s head should be stabilized, and their back should be elevated to minimize swallowing difficulties.
- Physical Restraints: These can help manage uncontrolled movements during treatment.
- Use of Mouth Props and Finger Splints: These tools can assist in controlling involuntary jaw movements.
- Gentle Handling: Avoid abrupt movements to prevent triggering the startle reflex.
- Local Anesthesia (LA): Administered with caution, ensuring stabilization to prevent sudden movements.
- Premedication: Medications may be given to alleviate muscle hypertonicity, manage anxiety, and reduce involuntary movements.
- General Anesthesia (GA): Reserved for cases that are too challenging to manage with other methods.
Postnatal Period: Developmental Milestones
The postnatal period, particularly the first year of life, is crucial for a child's growth and development. This period is characterized by rapid physical, motor, cognitive, and social development. Below is a summary of key developmental milestones from birth to 52 weeks.
Neonatal Period (1-4 Weeks)
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Physical Positioning:
- In the prone position, the child lies flexed and can turn its head from side to side. The head may sag when held in a ventral suspension.
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Motor Responses:
- Grasp reflex is active, indicating neurological function.
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Visual Preferences:
- Shows a preference for human faces, which is important for social development.
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Physical Characteristics:
- Face is round with a small mandible.
- Abdomen is prominent, and extremities are relatively short.
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Criteria for Assessing Premature Newborns:
- Born between the 28th to 37th week of gestation.
- Birth weight of 2500 grams (5-8 lb) or less.
- Birth length of 47 cm (18 ˝ inches) or less.
- Head length below 11.5 cm (4 ˝ inches).
- Head circumference below 33 cm (13 inches).
4 Weeks
- Motor Development:
- Holds chin up and can lift the head momentarily to the plane of the body when in ventral suspension.
- Social Interaction:
- Begins to smile, indicating early social engagement.
- Visual Tracking:
- Watches people and follows moving objects.
8 Weeks
- Head Control:
- Sustains head in line with the body during ventral suspension.
- Social Engagement:
- Smiles in response to social contact.
- Auditory Response:
- Listens to voices and begins to coo.
12 Weeks
- Head and Chest Control:
- Lifts head and chest, showing early head control with bobbing motions.
- Defensive Movements:
- Makes defensive movements, indicating developing motor skills.
- Auditory Engagement:
- Listens to music, showing interest in auditory stimuli.
16 Weeks
- Posture and Movement:
- Lifts head and chest with head in a vertical axis; symmetric posture predominates.
- Sitting:
- Enjoys sitting with full truncal support.
- Social Interaction:
- Laughs out loud and shows excitement at the sight of food.
28 Weeks
- Mobility:
- Rolls over and begins to crawl; sits briefly without support.
- Grasping Skills:
- Reaches for and grasps large objects; transfers objects from hand to hand.
- Vocalization:
- Forms polysyllabic vowel sounds; prefers mother and babbles.
- Social Engagement:
- Enjoys looking in the mirror.
40 Weeks
- Independent Sitting:
- Sits up alone without support.
- Standing and Cruising:
- Pulls to a standing position and "cruises" or walks while holding onto furniture.
- Fine Motor Skills:
- Grasps objects with thumb and forefinger; pokes at things with forefinger.
- Vocalization:
- Produces repetitive consonant sounds (e.g., "mama," "dada") and responds to the sound of their name.
- Social Play:
- Plays peek-a-boo and waves goodbye.
52 Weeks
- Walking:
- Walks with one hand held and rises independently, taking several steps.
- Object Interaction:
- Releases objects to another person on request or gesture.
- Vocabulary Development:
- Increases vocabulary by a few words beyond "mama" and "dada."
- Self-Care Skills:
- Makes postural adjustments during dressing, indicating growing independence.
Paralleling Technique in Dental Radiography
Overview of the Paralleling Technique
The paralleling technique is a method used in dental radiography to obtain accurate and high-quality images of teeth. This technique ensures that the film and the long axis of the tooth are parallel, which is essential for minimizing distortion and maximizing image clarity.
Principles of the Paralleling Technique
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Parallel Alignment:
- The fundamental principle of the paralleling technique is to maintain parallelism between the film (or sensor) and the long axis of the tooth in all dimensions. This alignment is crucial for accurate imaging.
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Film Placement:
- To achieve parallelism, the film packet is positioned farther away from the object, particularly in the maxillary region. This distance can lead to image magnification, which is an undesirable effect.
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Use of a Longer Cone:
- To counteract the magnification caused by increased film distance, a
longer cone (position-indicating device or PID) is employed. The longer
cone helps:
- Reduce Magnification: By increasing the distance from the source of radiation to the film, the image size is minimized.
- Enhance Image Sharpness: A longer cone decreases the penumbra (the blurred edge of the image), resulting in sharper images.
- To counteract the magnification caused by increased film distance, a
longer cone (position-indicating device or PID) is employed. The longer
cone helps:
-
True Parallelism:
- Striving for true parallelism enhances image accuracy, allowing for better diagnostic quality.
Film Holder and Beam-Aligning Devices
- Film Holder:
- A film holder is necessary when using the paralleling technique, as it helps maintain the correct position of the film relative to the tooth.
- Some film holders are equipped with beam-aligning devices that assist in ensuring parallelism and reducing partial exposure of the film, thereby eliminating unwanted cone cuts.
Considerations for Pediatric Patients
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Size Adjustment:
- For smaller children, the film holder may need to be reduced in size to accommodate both the film and the child’s mouth comfortably.
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Operator Error Reduction:
- Proper use of film holders and beam-aligning devices can help minimize operator error and reduce the patient's exposure to radiation.
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Challenges with Film Placement:
- Due to the shallowness of a child's palate and floor of the mouth, film placement can be somewhat compromised. However, with careful technique, satisfactory films can still be obtained.
Pulpotomy
Pulpotomy is a dental procedure that involves the surgical removal of the coronal portion of the dental pulp while leaving the healthy pulp tissue in the root canals intact. This procedure is primarily performed on primary (deciduous) teeth but can also be indicated in certain cases for permanent teeth. The goal of pulpotomy is to preserve the vitality of the remaining pulp tissue, alleviate pain, and maintain the tooth's function.
Indications for Pulpotomy
Pulpotomy is indicated in the following situations:
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Deep Carious Lesions: When a tooth has a deep cavity that has reached the pulp but there is no evidence of irreversible pulpitis or periapical pathology.
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Trauma: In cases where a tooth has been traumatized, leading to pulp exposure, but the pulp is still vital and healthy.
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Asymptomatic Teeth: Teeth that are asymptomatic but have deep caries that are close to the pulp can be treated with pulpotomy to prevent future complications.
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Primary Teeth: Pulpotomy is commonly performed on primary teeth that are expected to exfoliate naturally, allowing for the preservation of the tooth until it is ready to fall out.
Contraindications for Pulpotomy
Pulpotomy is not recommended in the following situations:
-
Irreversible Pulpitis: If the pulp is infected or necrotic, a pulpotomy is not appropriate, and a pulpectomy or extraction may be necessary.
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Periapical Pathology: The presence of periapical radiolucency or other signs of infection at the root apex indicates that the pulp is not healthy enough to be preserved.
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Extensive Internal Resorption: If there is significant internal resorption of the tooth structure, the tooth may not be viable for pulpotomy.
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Inaccessible Canals: Teeth with complex canal systems that cannot be adequately accessed may not be suitable for this procedure.
The Pulpotomy Procedure
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Anesthesia: Local anesthesia is administered to ensure the patient is comfortable and pain-free during the procedure.
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Access Opening: A high-speed bur is used to create an access opening in the crown of the tooth to reach the pulp chamber.
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Removal of Coronal Pulp: The coronal portion of the pulp is carefully removed using specialized instruments. This step is crucial to eliminate any infected or necrotic tissue.
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Hemostasis: After the coronal pulp is removed, the area is treated to achieve hemostasis (control of bleeding). This may involve the use of a medicated dressing or hemostatic agents.
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Application of Diluted Formocresol: A diluted formocresol solution (typically a 1:5 or 1:10 dilution) is applied to the remaining pulp tissue. Formocresol acts as a fixative and has antibacterial properties, helping to preserve the vitality of the remaining pulp and prevent infection.
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Pulp Dressing: A biocompatible material, such as calcium hydroxide or mineral trioxide aggregate (MTA), is placed over the remaining pulp tissue to promote healing and protect it from further injury.
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Temporary Restoration: The access cavity is sealed with a temporary restoration to protect the tooth until a permanent restoration can be placed.
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Follow-Up: The patient is scheduled for a follow-up appointment to monitor the tooth's healing and to place a permanent restoration, such as a stainless steel crown, if the tooth is a primary tooth.
Erythroblastosis fetalis
Blue-green colour of primary teeth only. It is due to excessive haemolysis of
RBC. The Staining occurs due to diffusion of bilirubin and biliverdin into the
dentin
Porphyria
Purplish brown pigmentation. to light and blisters on The other features hands
and face e Hypersensitivity are are red red coloured urine, urine,
Cystic fibrosis
(Yellowish gray to dark brown. It is due to tetracycline, which is the drug of
choice in this disease
Tetracycline
Yellow or yellow-brown pigmentation in dentin and to a lesser extent in enamel
that are calcifying during the time the drug is administered. The teeth
fluoresce yellow under UV light
Xylitol and Its Role in Dental Health
Xylitol is a naturally occurring sugar alcohol that is widely recognized for its potential benefits in dental health, particularly in the prevention of dental caries.
Properties of Xylitol
- Low-Calorie Sweetener: Xylitol is a low-calorie sugar substitute that provides sweetness without the high caloric content of traditional sugars.
- Natural Occurrence: It is found in small amounts in various fruits and vegetables and can also be produced from birch wood and corn.
Mechanism of Action
- Inhibition of Streptococcus mutans:
- Xylitol has been shown to inhibit the growth of Streptococcus mutans, the primary bacterium responsible for dental caries.
- It disrupts the metabolism of these bacteria, reducing their ability to produce acids that demineralize tooth enamel.
Research and Evidence
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Studies by Makinen:
- Dr. R. Makinen has conducted extensive research on xylitol, collaborating with various researchers worldwide.
- In 2000, he published a summary titled “The Rocky Road of Xylitol to its Clinical Application,” which highlighted the challenges and successes in the clinical application of xylitol.
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Caries Activity Reduction:
- Numerous studies indicate that xylitol chewing gum significantly reduces caries activity in both children and adults.
- The evidence suggests that regular use of xylitol can lead to a decrease in the incidence of cavities.
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Transmission of S. mutans:
- Research has shown that xylitol chewing gum can decrease the transmission of S. mutans from mothers to their children, potentially reducing the risk of early childhood caries.
Applications of Xylitol
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Incorporation into Foods and Dentifrices:
- Xylitol has been tested as an additive in various food products and dental care items, including toothpaste and mouth rinses.
- Its sweetening properties make it an appealing option for children, promoting compliance with oral health recommendations.
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Popularity as a Caries Prevention Strategy:
- The use of xylitol chewing gum is gaining traction as an effective caries prevention strategy, particularly among children.
- Its palatable taste and low-calorie nature make it an attractive alternative to traditional sugary snacks.
White Spot Lesions (Incipient Caries)
White spot lesions, also known as incipient caries, are early signs of dental caries that manifest as opaque areas on the enamel surface. These lesions are significant indicators of the demineralization process that occurs before the development of cavitated carious lesions.
Characteristics of White Spot Lesions
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Appearance:
- White spots are characterized by a high concentration of minerals and fluoride at the surface layer of the enamel, which diffracts light and creates an opacity that is clinically visible.
- These lesions typically appear as white, chalky areas on the enamel surface.
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Caries Development:
- While white spots are recognized as the first clinical evidence of developing caries, the carious process actually begins much earlier at the microscopic level.
- Demineralization of the enamel occurs before the white spot becomes visible, indicating that the caries process is ongoing.
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Influence of Fluoride:
- The presence of fluoride can positively affect the appearance and
texture of white spot lesions:
- With Fluoride: The surface of the white spot becomes smooth and shiny, indicating some degree of remineralization.
- Without Fluoride: The lesion appears rough and chalky, suggesting a higher level of demineralization and a greater risk of progression to cavitation.
- The presence of fluoride can positively affect the appearance and
texture of white spot lesions:
Clinical Considerations
-
Probing:
- It is important to avoid probing the surface of white spot lesions too aggressively. Although the surface may appear intact, the underlying enamel is mineral-deficient and weak.
- Excessive probing can lead to the breakdown of these weak layers, potentially resulting in cavitation and the progression of caries.
-
Management:
- Early intervention is crucial for managing white spot lesions.
Strategies may include:
- Fluoride Treatments: Application of fluoride varnishes or gels to promote remineralization.
- Dietary Counseling: Educating patients about reducing sugar intake and improving oral hygiene practices to prevent further demineralization.
- Monitoring: Regular dental check-ups to monitor the progression of white spot lesions and assess the effectiveness of preventive measures.
- Early intervention is crucial for managing white spot lesions.
Strategies may include: