Developmental Disorders Of Teeth Question And Answers

Developmental Disorders Of Teeth And Orofacial Structures Essay Questions

Question 1. Enumerate the developmental malformation affecting the tooth structure and briefly explain each condition.
(or)
Describe enamel hypoplasia. Explain the pathogenesis and clinical features of each condition.
(or)
Enumerate the causes for generalized discoloration of teeth and describe the pathogenesis and clinical characteristic of each condition.
Answer: Hypoplasia refers to the defective formation of an organ or structure.

Enamel hypoplasia resulting in generalized discoloration of teeth is of 2 types which are as follows:

1. Environmental: Dental fluorosis
2. Genetic:

Read And Learn More: Oral Medicine and Radiology Question And Answers

• 1. Amelogenesis imperfecta
  2. Dentinogenesis imperfecta

1. Environmental Causes

Dental Fluorosis:

• It is a condition characterized by mottled enamel resulting from drinking water with increased fluoride content (above 1 ppm) during the formative phase of dentition.
• The ameloblasts are affected due to the increased fluoride resulting in defective or deficient enamel matrix formation and calcification.

Dental Fluorosis Clinical Features: Fluorosis affects only permanent dentition. The clinical appearance depends on the amount and duration of fluoride intake.

The mottled appearances of enamel include:

• Questionable change: Occasional white spots on the enamel
• Mild change: Opaque white spots involving more tooth surface
• Moderate and severe changes: Pitting and brownish discoloration of the enamel and corroded changes.

Severely affected enamel may show a tendency to chip off and get fractured.

Dental Fluorosis Radiographic findings: No abnormalities noted specifically to fluorosis.

Dental Fluorosis Treatment: Cosmetic, restorative procedures.

2. Genetic Causes:

1. Amelogenesis imperfecta (AI)

• Amelo = enamel
• Genesis = production
• Imperfecta = defective

AI is a developmental defect of enamel resulting in brown discoloration of teeth. It is of 2 types:

1. Hereditary enamel hypoplasia
2. Hereditary enamel hypo calcification.

Amelogenesis imperfecta Pathogenesis:

• In the primary phase of enamel development, the deposition of the enamel matrix begins at the amelodentinal junction and advances toward the outer surface.
• The enamel organ matrix is composed of 65% organic material and water and 35% of inorganic material.
• In the second phase of the developmental process, water and organic materials are removed and replaced by mineral salts, composing about 96% in the final structure.
• A disturbance occurring in the primary phase results in hypoplasia with an altered shape of teeth. The amount of enamel formed will be small in quantity but fully calcified; hence the hardness of the teeth will be reasonable.
• A disturbance occurring in the second phase results in hypo calcification, where the enamel matrix is deposited in normally in quantity, but the calcification will be incomplete. This poor-quality of enamel is quickly worn off and exposes the underlying dentin.

Amelogenesis imperfecta Clinical Features:

• AI affects both deciduous and permanent teeth.
• Teeth are of abnormal size and shape.
• In the hypoplastic type, the teeth are brown- yellow with a smooth and glossy surface. Consistency is hard.
• In the hypo calcification type, the teeth are dark brown; the surface will be rough and dull.

The abrasion and chipping off of enamel result in loss of structural configuration.

Amelogenesis imperfecta Radiographic Features:

• In the hypoplastic type, the tracing of enamel is difficult as its thickness is reduced in spite of normal calcification.
• In hypo calcification, the density of enamel and dentin are the same.

Amelogenesis imperfecta Treatment:

• Restorative management
• Veneering
• Crown and bridge.

2. Dentinogenesis imperfecta (DI)

• Dens = tooth
• Genesis = formation
• Imperfecta = defective

DI is a developmental disturbance resulting in poor-quality of dentin but normal enamel.

Dentinogenesis imperfecta Pathogenesis:

• The dentin is composed of low organic content and increased water with the normal calcium-phosphorous ratio. The enamel is normal, but the pulp chamber and dentin enamel junction are absent.
• The loss of scalloping of DEJ which is responsible for fixing the enamel to the dentin results in increased fracture susceptibility of the enamel.

Dentinogenesis imperfecta Clinical Features:

• The teeth appear normal in size, but there is a decrease in the thickness and length of the roots.
• The teeth will have a blue opalescent hue.
• Exposure of dentin due to fractured enamel results in pulp-periapical lesions and teeth loss.

Dentinogenesis imperfecta Radiographic Findings:

• The obliterated pulp chamber and pulp canals
• Smaller roots.

Dentinogenesis imperfecta Treatment:

• Restorative management
• Veneering
• Crown and bridge.

Developmental Disorders Of Teeth And Orofacial Structures Short Notes

Question 1. Enumerate the developmental distur¬bances associated with orofacial changes.
Answer:

Generalized Developmental Disturbances with Specific Oral Manifestations:

• Craniofacial dysostosis
• Cleidocranial dysostosis
• Achondroplasia
• Hereditary ectodermal dysplasia
• Osteogenesis imperfecta
• Albers-Schonberg disease.

Generalized Developmental Disturbances with Secondary Oral Manifestations:

• Hereditary intestinal polyposis syndrome (Peutz-Jaggers syndrome)
• Sickle cell anemia
• Cooley’s anemia (Thalassemia)
• Hemophilia.

Local Developmental Disturbance of Nonodon-togenic Structures:

• Benign migratory glossitis
• Fissured tongue
• Cleft lip and palate
• Fordyce’s granules
• Leukemia.

Local Developmental Disturbances Affecting Odontogenic Structures:

• Amelogenesis imperfecta
• Dentinogenesis imperfecta
• Dens in Dente
• Dentin dysplasia
• Gemination, fusion, and concrescences
• Supernumerary teeth, anodontia, oligodontia.

Question 2. Benign migratory glossitis (geographic tongue).
Answer:

• This condition affects the dorsal and lateral aspects of the tongue as large, red patches with slightly raised, white circinate borders. Usually, multiple lesions occur at a time.

• The red patches are due to the atrophy of filiform papillae, and a white boundary is due to the hypertrophy of the papillae. The lesion resembled the world map and was known as the geographic tongue.
• Usually asymptomatic but occasionally cause a burning sensation. The lesions disappear in weeks, and the papilla regenerates but a new lesion appears at another site which gives a picture of the lesion migrating from one area to another and is hence known as migratory glossitis.
• Diagnosis is based on the appearance of the lesion, its location, and recurrence.
• Treatment is not needed, but reassurance should be given to the patient about the simple nature. In some conditions, vitamin supplements and topical anesthetics are used.

Question 3. Fissured tongue.
Answer:

• It is a congenital malformation of the dorsal surface of the tongue; otherwise known as a scrotal tongue.
• The dorsal surface of the tongue shows furrows, grooves, and clefts, directed anteroposteriorly and laterally. The lesions develop over a long period and are asymptomatic. Rarely do these grooves and fissures act a source for food debris accumulation and lead to bacterial infection.
• The burning sensation may be the related symptom.
• Fissured tongue is associated with Melkers-son-Rosenthal syndrome and pernicious anemia.

Fissured tongue Treatment: Improved oral hygiene with home care irrigation.

Question 4. Macroglossia.
Answer: Macroglossia is a larger size tongue that interferes with speech and mastication.

There are two types:

1. Primary macroglossia: Hereditary condition seen in cretinism and Down syndrome. Hemangioma and lymphangioma are the frequent causes of macroglossia.
2. Secondary macroglossia: It is an acquired condition to local or systemic factors like untreated malocclusion, prolonged edentulous condition, neurofibroma, amyloidosis, and benign or malignant muscle tumors of the tongue.

The underlying cause needs to be corrected for effective management.

Question 5. Lingual varies.
Answer:

• Varices are the varicose vein present at the ventral surface of the tongue in some elderly individuals usually above 60 years of age. It appears as a purple-red or bluish-black, raised lesion measuring 2-5 mm in size.
• Varices are multiple in number and appear as black caviar (caviar spot of the tongue).
• The varicose veins are dilated, torturous, soft consistency, and blanch on pressure. Sometimes, it occurs at labial and buccal mucosa.
• Usually asymptomatic and treatment is not needed.
• Clinical significance: Sometimes thrombi develop within varicose veins and appear as a tumor-like growth.

Question 6. Fordyce granules.
Answer:

• Fordyce granules are the sebaceous glands studded with the oral mucosa. They are the normal variant of the oral cavity and are commonly seen on the buccal mucosa bilaterally. These granules are yellow-orange in color, small, elevated, and sometimes present in clusters.
• It is also seen in the labial mucosa. These granules arise during the age of puberty and have a male predilection.
• Asymptomatic condition. No treatment is necessary.

Question 7. Leukoedema.
Answer:

• Leukoedema is a developmental condition in which the buccal mucosa is milky white or bluish-tinted, folded or striated in appearance. Usually bilateral and symmetrical. Sometimes involving the entire oral mucosa in a diffused pattern.
• The edematous condition is due to intra-cellular edema of epithelial cells of oral mucosa and is responsible for the slightly raised appearance.
• When the mucosa is stretched, it assumes a normal pink color and smooth appearance. Smoking may exacerbate the appearance. Asymptomatic and no treatment is required.
• Leukoedema Differential diagnosis: White sponge nevus, leukoplakia

Question 8. Supernumerary teeth.
Answer:

Supernumerary teeth are extra teeth and are a quite common developmental condition. These extra teeth may completely erupt or be impacted. Size and shape may resemble the normal tooth or may be variable.

This condition is associated with aberrant tooth bud formation.

The most common type of supernumerary teeth are:

• Mesiodens erupt between the maxillary central incisors either in the arch or on the palatal aspect.
• Distomolar erupts distal to maxillary 3rd molars and
• Paramolar erupt adjacent to 1st, or 2nd molars.

If the supernumerary teeth are present in the arch and resemble the adjacent teeth, then it is known as supplementary teeth.

Supernumerary teeth Clinical Significance:

• Multiple erupted and impacted super-numerary teeth are common in cleidocranial dysplastic syndrome.
• Malocclusion, food lodgement, dental caries, and gingivitis or periodontitis are the problems associated with erupted teeth.
• The development of odontogenic cysts and tumors are also arising from these extra teeth.

Question 9. Tori
(or)
Exostosis.
Answer:

• Tori is the dense bony prominence that develops during jaw formation and development. They occur both in the maxilla and mandible.
• In the maxilla, tori occur as a dense bony growth at the hard palate along with the midline. Mandibular tors are usually bilateral and appear as lobular bony nodules, positioned inferior and lingual to premolars.
• They are slow growing and asymptomatic. Normal mucosa covers the surface. Larger tori may cause a disturbance in prosthetic placement and requires surgical removal.
• Exostoses are developmental bony growth, which occurs as nodules on the palate, alveolus, or jaw bones. They are hard in consistency and asymptomatic. Infrequent findings and treatment are not required.

Question 10. Tetracycline stain.
Answer:

• Tetracycline therapy is an environmental agent that causes developmental discoloration of teeth without hypoplasia.
• Tetracycline is a broad-spectrum antibiotic used to treat chronic infectious diseases and many childhood infections.
• When taken by the pregnant mother, the drug can traverse the placental barrier and cause staining of the primary dentition. Children below ten years of age should not be medicated with tetracycline.
• The tetracycline gets incorporated into the enamel during development and gives a gray to yellow appearance depending on the chemical configuration of the drug, and total dosage. These stains involve teeth in correlation with the chronological pattern of tooth development at the time of administration.
• The entire dentition may be affected by long-term therapy.
  These stains cause an only esthetic disturbance, and hence veneering of teeth is ade¬quate to improve the appearance.

Question 11. Lingual tonsils
(or)
Foliate papillitis
(or)
Papillitis.
Answer:

• The posterior and posterolateral aspect of the dorsal surface of the tongue contains aggregates of lymphoid tissues with circumvallate papilla (on the posterior dorsum) and folia¬tes papilla (on the posterolateral tongue surfaces) bilaterally.
• These natural aggregates occasionally become enlarged, hyperplastic, and sometimes inflamed. This condition mimics malignancy.
• The enlarged lingual tonsils appear as elevated, yellow-colored submucosal swellings on the posterolateral surface of the tongue bilaterally. This may be accompanied by red, inflamed foliate papillae which are often painful.
• Lymphoid aggregates commonly occur as movable nodules on the pharyngeal-tonsillar region, uvula, and soft palate. Rarely they may be present on the buccal mucosa, floor of the mouth and lingual vestibules.

• Upper respiratory tract infections may aggravate these conditions. Diagnosis is based on clinical appearance, site, and duration. There are no severe sequelae of this condition.

Question 12. Linea alba.
Answer:

• The linea alba is a white line that occurs on the buccal mucosa parallel to the line of occlusion bilaterally. This extends into the triangular area inside the labial commissure on the respective sides.
• This is a normal frictional response and appears distinctive in some individuals.
• The habit of taking coarse foods, smoking, and other irritants may increase the intensity of frictional cornification.
  Variable degrees of keratinization in the course of linea alba in the same individual are also common.
• It is an asymptomatic condition and no need for any treatment.
• Differential diagnosis: Lichen planus, liche¬noid reaction, leukoplakia.

Developmental Disorders Of Teeth And Orofacial Structures Multiple Choice Questions

Question 1. The joining of two individual adjacent tooth buds by enamel, dentin, and cementum is known as.

1. Concrescence
2. Fusion
3. Gemination
4. Odontome

(Note: Fusion is the joining of two individual adjacent tooth buds by enamel, dentin, and cementum during the developmental stage, resulting in a giant tooth).

Answer: 2. Fusion

Question 2. The fusion of two teeth only by cementum is known as.

1. Concrescence
2. Fusion
3. Gemination
4. Odontome

Answer: 1. Concrescence

Question 3. The division of a single tooth bud resulting in the formation of two teeth is called as.

1. Concrescence
2. Supplemental
3. Gemination
4. Hyperdontia

(Note: Gemination is an attempted division of a single tooth germ resulting in complete or incompletely separated crowns with single root and root canal. Also known as Siamese twins).

Answer: 3. Gemination

Question 4. The enlarged midfoot structure, with a large pulp chamber and short apex, is known as.

1. Tuberculate
2. Submerged
3. Dilaceration
4. Taurodontism

(Note: Taurodontism is seen in amelogenesis imperfecta, Down syndrome, and Klinefelter syndrome).

Answer: 4. Taurodontism

Question 5. Dens in Dente is common in.

1. Maxillary molars
2. Mandibular molars
3. Maxillary lateral incisors
4. Mandibular canines

Answer: 3. Maxillary lateral incisors

Question 6. Harelip denotes.

1. Cleft lip
2. Angular cheilitis
3. Double lip
4. Lip pits

Answer: 1. Cleft lip

Question 7. Developmental condition of absence of some teeth is denoted as.

1. Anodontia
2. Oligodontia
3. Isodontia
4. Microdontia

Answer: 2. Oligodontia

Question 8. Oligodontia commonly manifests as missing.

1. Maxillary lateral incisors
2. Mandibular lateral incisors
3. Maxillary canines
4. Mandibular canines

Answer: 1. Maxillary lateral incisors

Question 9. Complete anodontia may be seen in.

1. Hypophosphatasia
2. Rickets
3. Hypothyroidism
4. Cleidocranial dysplasia
5. (Note: Complete anodontia may be seen in rickets and ectodermal dysplasia).

Answer: 2. Rickets

Question 10. Multiple supernumerary teeth are seen in.

1. Hyperthyroidism
2. Hyperparathyroidism
3. Down’s syndrome
4. Cleidocranial dysplasia

Answer: 4. Cleidocranial dysplasia

Question 11. A maxillary lateral incisor with a pouch on the crown or root is known as.

1. Dens in Dente
2. Enamel pearl
3. Peg laterals
4. Accessory cingulum

Answer: 1. Dens in dente

Question 12. The consequence of supernumerary teeth is.

1. Esthetic disturbance
2. Caries progression
3. Adjacent root resorption
4. Odontogenic harmatoma

Answer: 3. Adjacent root resorption

Question 13. Fordyce granules represent.

1. Salivary gland aberrancy
2. Sebaceous choristoma
3. Adipose tissue atrophy
4. Sweat gland orifice

Answer: 2. Sebaceous choristoma

Question 14. A large head with mango loid facies is seen in.

1. Hemophilic patients
2. Thalassemia individuals
3. Sickle cell patients
4. Thrombocytopenic individuals

Answer: 2. Thalassemia individuals

Question 15. Tower shaped skull is a typical feature of.

1. Thalasemia
2. Sickle cell anemia
3. Hydrocephaly
4. Brachycephaly

(Note: Tower-shaped skull is a typical feature of sickle cell anemia and oxycephaly).

Answer: 2. Sickle cell anemia

Question 16. Upper lip cleft occurs at the.

• 4th and 5th week of intrauterine life
• 10th week of intrauterine life
• 6th and 7th week of intrauterine life
• 14th week of intrauterine life

Answer: 3. 6th and 7th week of intrauterine life

Question 17. A cleft palate occurs at.

• 4th and 5th week of intrauterine life
• 10th week of intrauterine life
• 6th and 7th week of intrauterine life
• 8th week of intrauterine life

Answer: 4. 8th week of intrauterine life

Question 18. Schizodontia results in.

1. One normal and one supernumerary tooth
2. Two supernumerary teeth
3. Two normal teeth
4. One normal and one impacted tooth

(Note: Schizodontia refers to the twining of a tooth bud by complete cleavage, resulting in one normal and one supernumerary tooth).

Answer: 1. One normal and one supernumerary tooth

Question 19. Synodontia refers to.

1. Fusion of two crowns
2. Fusion of two separate tooth germs
3. Fusion of two teeth roots
4. Fusion of two deciduous tooth germs

Answer: 2. Fusion of two separate tooth germs

Question 20. Concrescence occurs.

1. Before root completion
2. After root completion
3. Before crown completion
4. After crown calcification

Answer: 2. After root completion

Question 21. Sharp curvature on the crown or root of the tooth is denoted as.

1. Tuberculate
2. Dens invaginatous
3. Dilaceration
4. Taurodontism

Answer: 3. Dilaceration

Question 22. If a deciduous tooth causes injury to the permanent tooth bud, the permanent tooth will be dilacerated.

1. Dilacerated
2. Nonvital
3. Hypoplastic
4. Ankylosed

Answer: 1. Dilaceration

Question 23. Talon’s cusp is an associated finding of.

1. Pierre Robin syndrome
2. Stickler’s syndrome
3. Velocardiofacial syndrome
4. Rubinstein Taybi syndrome

(Note: Talon’s cusp is an associated finding of Rubinstein Taybi syndrome, Ellis-van Creveld syndrome, and Sturge-Webber syndrome).

Answer: 4. Rubinstein Taybi syndrome

Question 24. Leong’s premolar denotes the condition of dens evaginates.

1. Dens invaginatous
2. Dens evaginates
3. Supernumerary tooth
4. Supplementary premolar

Answer: 2. Dens evaginates

Question 25. Teeth present at birth are known as.

1. Natal teeth
2. Neonatal teeth
3. Hyperdontia
4. Pseudo teeth

(Note: Teeth erupt within 28 days of birth is known as neonatal teeth. Both natal and neonatal teeth are hornified epithelial struc¬tures).

Answer: 1. Natal teeth

Question 26. Turner’s hypoplasia frequently involves.

1. Deciduous mandibular molars
2. Deciduous canines
3. Maxillary and mandibular premolars
4.  Mandibular anterior teeth

(Note: Turner’s hypoplasia frequently involves maxillary and mandibular premolars and permanent maxillary central incisors).

Answer: 3. Maxillary and mandibular premolars

Question 27. Tulip shape teeth are the finding in.

1. Amelogenesis imperfecta
2. Dentinogenesis imperfecta
3. Regional odontodysplasia
4. Ectodermal dysplasia

Answer: 2. Dentinogenesis imperfecta

Question 28. Ghost-like teeth in dentinogenesis imperfecta are the result of.

1. Loss of structural morphology
2. Altered pattern of eruption
3. Lack of density
4. Dead space in dentin

(Note: Lack of density is due to lack of calci¬fication).

Answer: 3. Lack of density

Developmental Disorders Of Teeth And Orofacial Structures Viva Voce

Question 1. What is Melkersson-Rosenthal syndrome.
Answer: It is a group of manifestations including cheilitis granulomatosa, fissured tongue, multiple granulomatous swellings, and facial palsy. The proposed etiology is gene mutation.

Question 2. Classification of supernumerary teeth.
Answer: Based on morphology and location, the supernumerary teeth are classified into the following types:

1. Conical (mesiodens)
2. Tuberculate (barrel-shaped teeth on the palatal aspect of central incisors often in pair)
3. Supplemental (duplication of the tooth on the arch)
4. Odontome.

Developmental Disorders Of Teeth And Orofacial Structures Highlights

• Developmental disorders involve a sequence of interruptions in single or multiple organs during the formative and growth periods. These conditions may be mild or may be very severe and morbid. Oral manifestations many times help to recognize serious systemic conditions.
• The diagnosis depends on the unique clinical features of each condition supported by pathognomic radiographic findings. This chapter is the compilation of developmental defects involving craniofacial structures including teeth and oral cavity.