Protecting All Children’s Teeth Dental Development http://www.aap.org/oralhealth/pact

Introduction It is important for child health providers to understand normal dental development so that proper anticipatory guidance can be provided to families, deviations from normal can be recognized, and accurate decisions about intervention can be made. http://www.aap.org/oralhealth/pact

Learner Objectives Upon completion of this presentation, participants will be able to: Recall the typical pattern and timing of tooth eruption. Describe instances in which a practitioner should be concerned about eruption and refer for evaluation. List medical causes of premature and delayed tooth exfoliation. State at least 4 common etiologies of tooth discoloration. Correctly identify symptoms associated with teething and summarize proper teething management. Outline common symptoms and causes of malocclusion. http://www.aap.org/oralhealth/pact

Normal Development Oral structures begin to form during the third and fourth weeks of embryonic development. The teeth begin to develop around the sixth week of fetal life. Development continues throughout fetal life and beyond. Notes: Germ cells from the ectoderm, mesoderm, and endoderm all contribute to tooth formation. Tooth development is divided into the following stages: the bud, the cap, the bell, and crown (maturation). An insult can happen at any or multiple points in the development process and lead to abnormal outcomes. For example, a febrile illness can cause enamel hypoplasia and excess fluoride ingestion can result in fluorosis. http://www.aap.org/oralhealth/pact

Tooth Eruption: Primary Teeth Primary teeth begin to erupt around 6 months of age. Eruption is completed by 24 to 36 months. Delays of more than 12 months merit further dental evaluation. Notes: The order of eruption of the 20 primary and 32 permanent teeth is fairly predictable, although the timing may vary. Girls’ teeth usually erupt slightly earlier than boys. Delays in tooth eruption can be familial. http://www.aap.org/oralhealth/pact

Tooth Eruption: Primary Teeth Eruption is usually symmetrical (lower teeth before upper) in the following pattern for primary teeth: Central incisors Lateral incisors First molars Canines Second molars Exfoliation often follows a similar pattern. Notes: A helpful mnemonic to remember the timing of primary eruption is the 7+4 rule. At 7 months of age, children should have their first teeth; at 11 months (4 months later), they should have 4 teeth. This pattern continues as follows: 15 months = 8 teeth; 19 months = 12 teeth; 23 months = 16 teeth; 27 months = 20 teeth. Glossary: Exfoliation: The shedding of a superficial layer of a tooth. http://www.aap.org/oralhealth/pact

Tooth Eruption: Permanent Teeth Eruption for the permanent teeth is similar to that of the primary teeth. Eruption of the permanent teeth begins between 5 and 7 years of age and usually finishes by 13 to 14 years. http://www.aap.org/oralhealth/pact

Tooth Eruption: Permanent Teeth The typical pattern for the eruption of permanent teeth is: Central incisors Lateral incisors First molars Premolars Canines Second molars Third molars (wisdom teeth) Notes: Not everyone develops or erupts third molars. http://www.aap.org/oralhealth/pact

Natal and Neonatal Teeth Some infants erupt teeth before birth (natal teeth) or shortly thereafter (neonatal teeth). Extraction of these incisors may be considered if they are mobile, interfere with breastfeeding, or lead to Riga-Fede ulceration. Glossary: Riga-Fede Disease: Ulceration of the lingual frenum or ventral surface of the tongue in infants caused by abrasion of the tissue against natal or neonatal teeth. http://www.aap.org/oralhealth/pact

Delayed Eruption Delayed eruption of more than 12 months can be caused by: Endocrine disorders Genetic disorders Oral space issues Dense gingival tissue Dental infection Radiation therapy It is reasonable to refer a child who has not erupted a tooth by 18 months of age to a dentist if they are not seeing one already. Notes: Oral space issues such as another tooth blocking eruption or impacted teeth can delay eruption. Endocrine disorders that can delay tooth eruption include hypothyroidism, disorders of calcium/phosphorus metabolism, and hypopituitarism (deficient production of growth hormones by the pituitary gland). Genetic disorders that can delay eruption include ectodermal dysplasias, Down syndrome, and cleidocranial dysostosis (a rare condition inherited in an autosomal dominant fashion and characterized by partial or complete absence of the clavicles, defective ossification of the skull, and faulty occlusion due to missing, misplaced, or supernumerary teeth). http://www.aap.org/oralhealth/pact

Early Exfoliation Early exfoliation may be the result of the following causes: Tooth destruction from dental caries Trauma Endocrine disorders, immune disorders, or other disorders Notes: Endocrine disorders such as diabetes and hypophosphatasia can cause early exfoliation. Immune disorders such as neutropenia, neutophil defects, and HIV can cause early exfoliation. Other disorders that cause early exfoliation include Ehlers Danlos syndrome type VIII, or eosinophilic granuloma/Langerhan’s Cell Histiocytosis. Glossary: Hypophosphatasia: A congenital metabolic disorder characterized by a deficiency of alkaline phosphatase and usually resulting in demineralization of bone. Neutropenia: Leukopenia in which the decrease in white blood cells is chiefly in neutrophils. http://www.aap.org/oralhealth/pact

Delayed Exfoliation Delayed tooth loss can be caused by a variety of disorders, including: Endocrine disorders such as hypothyroidism or hypopituitarism Ectodermal dysplasias Genetic disorders Notes: Genetic disorders that can caused delayed exfoliation include Down syndrome, Apert syndrome, Achondroplasia, and Osteogenesis imperfecta. Glossary: Hypopituitarism: Deficient production of growth hormones by the pituitary gland. http://www.aap.org/oralhealth/pact

Abnormal Teeth A number of tooth abnormalities can occur in development. These abnormalities can relate to the shape, color, physical structure, or number of teeth. http://www.aap.org/oralhealth/pact

Abnormal Teeth, continued Hypodontia can be caused by the same problems that delay eruption. Anodontia is extremely rare and most often associated with hypohydrotic ectodermal dysplasia. Hyperdontia can be associated with genetic disorders such as cleidocranial dysostosis and Gardner’s syndrome (Familial Adenomatous Polyposis). Notes: Problems that can cause hypodontia include Down syndrome, ectodermal dysplasias, chemotherapy, or radiation therapy. The prevalence of hypodontia is approximately 3% in the United States, excluding the absence of the third molars (wisdom teeth), which occurs in approximately 20% of individuals. Hyperdontia prevalence ranges from 0.1% to 3.8%. Glossary: Hypodontia: A congenital condition marked by a less than normal number of teeth; partial anodontia Anodontia: An especially congenital absence of teeth Hyperdontia: A congenital condition marked by a greater than normal number of teeth Cleidocranial dysostosis: A rare condition inherited in an autosomal dominant fashion and characterized especially by partial or complete absence of the clavicles, defective ossification of the skull, and faulty occlusion due to missing, misplaced, or supernumerary teeth Familial Adenomatous Polyposis: A disease of the large intestine that is marked by the formation especially in the colon and rectum of numerous adenomatous polyps which typically become malignant if left untreated; inherited as an autosomal dominant trait http://www.aap.org/oralhealth/pact

Tooth Shape Abnormal tooth shape can result from a variety of medical conditions. Hutchinson incisors and Mulberry teeth are caused by congenital syphilis. Notes: Conical teeth are caused by ectodermal dysplasias. Hutchinson Teeth http://www.aap.org/oralhealth/pact

Tooth Color Abnormalities in tooth color can result from a number of causes. Food pigments can stain the teeth, although these changes should be temporary. Smoking can also discolor the teeth. Excess fluoride intake can cause a range of color changes, from a lacy, chalky white discoloration to severe brown staining of the teeth. Notes: High fevers during tooth formation can cause tooth discoloration or lines in the teeth. http://www.aap.org/oralhealth/pact

Tooth Color, continued Abnormalities in tooth color can also be caused by the following: Nerve necrosis secondary to trauma Severe caries Tetracycline use by a pregnant mother in the second half of pregnancy or by a child early in life Oral iron supplementation Poor oral hygiene Medical problems Notes: The dark discoloration often caused by oral iron supplementation may require a dentist’s assistance for removal. Medical problems that can affect tooth color include porphyria, hyperbilirubinemia, and amelogenesis imperfecta. Glossary: Porphyria: Abnormalities of porphyrin metabolism characterized by excretion of excess porphyrins in the urine and by extreme sensitivity to light Hyperbilirubinemia: The presence of an excess of bilirubin in the blood Amelogenesis Imperfecta: Faulty development of tooth enamel that is genetically determined Iron Staining http://www.aap.org/oralhealth/pact

Teething Care Teething and symptoms attributed to teething are a common concern of parents. It is important to inform parents that none of these symptoms consistently and accurately predict when teething is about to occur: Congestion or cough Sleep disturbance Decreased appetite for liquids Vomiting Loose or increased stools Notes: A number of studies have looked at teething and associated symptoms, with the largest study observing that the symptoms of "increased biting, drooling, gum rubbing, sucking, irritability, wakefulness, ear rubbing, facial rash, decreased appetite for solid foods, and mild temperature elevation were all statistically associated with teething.” No single symptom occurred in more than 35% of infants. Serious symptoms such as fever (>100.4º F) and diarrhea should not be attributed to teething and may require further evaluation to rule out a bacterial source of infection. http://www.aap.org/oralhealth/pact

Teething Care, continued The recommended intervention for teething is the use of cold items because the cold acts as an anesthetic for the gums. Suggested items include: Pacifiers Spoons Clean wet washcloths Frozen bagels or bananas Refrigerated teething rings Notes: Teething rings should be placed in the refrigerator and not the freezer to prevent infants from developing fat necrosis. http://www.aap.org/oralhealth/pact

Teething Care, continued Topical teething gels sold over-the-counter (OTC) are often used for teething. These gels can carry serious risks, such as local reactions, seizures with overdose, and methemoglobinemia. If necessary, parents should be instructed on proper dosing of OTC analgesic medications, such as acetaminophen or ibuprofen. Glossary: Methemoglobinemia: The presence of methemoglobin in the blood due to conversion of part of the hemoglobin to this inactive form http://www.aap.org/oralhealth/pact

Malocclusion Malocclusion can be a functional problem, an aesthetic issue, or a hindrance to maintaining good oral hygiene. Examples of malocclusion include anterior open bite, anterior crossbite, and posterior crossbite. Glossary: Malocclusion: An abnormality in the coming together of teeth Anterior Open Bite: Vertical space between the upper and lower incisors resulting from opposing teeth failing to establish occlusal contact when the jaws are closed Anterior Cross Bite: Malocclusion in which the maxillary incisors are posterior to (behind) the mandibular incisors Posterior Crossbite: Malocclusion in which the posterior maxillary molars or premolars are lingually displaced inside of the mandibular teeth Anterior Open Bite Anterior Crossbite Posterior Crossbite http://www.aap.org/oralhealth/pact

Malocclusion, continued Signs and symptoms of malocclusion include: Abnormal alignment of teeth Abnormal appearance of the face Difficulty or discomfort when biting or chewing Bruxism Glossary: Bruxism: The habit of unconsciously gritting or grinding the teeth especially in situations of stress or during sleep http://www.aap.org/oralhealth/pact

Malocclusion, continued Malocclusion is usually genetic or congenital in origin. Examples of genetic causes include congenital absence of teeth, cleft lip or palate, skeletal disorders, and muscular problems. Malocclusion can also result from environmental factors, such as prolonged thumb sucking, pacifier use, or tongue thrusting. Patients with malocclusions should be referred to a dental professional. Notes: Helping families address pacifier and thumb sucking issues at an early age may prevent or minimize malocclusion. Physicians can encourage patients treated by dental professionals to use prescribed appliances, such as retainers, consistently and as directed by the dental professional. http://www.aap.org/oralhealth/pact

Question #1 A parent asks you how many "baby teeth" her child will eventually have. What is the most appropriate response? A. 18 teeth. B. 20 teeth. C. 28 teeth. D. 32 teeth. E. None of the above. http://www.aap.org/oralhealth/pact

Answer A parent asks you how many "baby teeth" her child will eventually have. What is the most appropriate response? A. 18 teeth. B. 20 teeth. C. 28 teeth. D. 32 teeth. E. None of the above. http://www.aap.org/oralhealth/pact

Question #2 Which of the following is true of malocclusion? A. It can be an aesthetic problem. B. It can interfere with proper oral hygiene. C. It can make eating difficult. D. Examples include an anterior open bite and a posterior crossbite. E. All of the above. http://www.aap.org/oralhealth/pact

Answer Which of the following is true of malocclusion? A. It can be an aesthetic problem. B. It can interfere with proper oral hygiene. C. It can make eating difficult. D. Examples include an anterior open bite and a posterior crossbite. E. All of the above. http://www.aap.org/oralhealth/pact

Question #3 You are seeing a 15-month-old healthy boy for his 15-month routine visit. He was not premature. The parents are concerned because he has not yet erupted any teeth, a finding you confirm on examination. Which is the most appropriate course of action? A. Reassure the family. If the child appears normal, you are not concerned unless no teeth have erupted by 2 years of age. B. Refer to a dentist for evaluation. C. Obtain a panoramic X-ray of the teeth to ensure that they have developed normally. D. Refer to an endocrinologist for evaluation, as delayed tooth eruption has a known association with several endocrinopathies. E. Wait 3 months and refer to a dentist if no teeth have erupted by the 18 month routine visit. http://www.aap.org/oralhealth/pact

Answer You are seeing a 15-month-old healthy boy for his 15-month routine visit. He was not premature. The parents are concerned because he has not yet erupted any teeth, a finding you confirm on examination. Which is the most appropriate course of action? A. Reassure the family. If the child appears normal, you are not concerned unless no teeth have erupted by 2 years of age. B. Refer to a dentist for evaluation. C. Obtain a panoramic X-ray of the teeth to ensure that they have developed normally. D. Refer to an endocrinologist for evaluation, as delayed tooth eruption has a known association with several endocrinopathies. E. Wait 3 months and refer to a dentist if no teeth have erupted by the 18 month routine visit. http://www.aap.org/oralhealth/pact

Question #4 True or False? Excess fluoride intake can cause irreversible tooth discoloration. A. True. B. False. http://www.aap.org/oralhealth/pact

Answer True or False? Excess fluoride intake can cause irreversible tooth discoloration. A. True. B. False. http://www.aap.org/oralhealth/pact

Question #5 When do the primary (baby) teeth begin to erupt? A. It varies from child to child. B. Around 6 months of age. C. Around 9 months of age. D. Around 12 months of age. E. Around 18 months of age. http://www.aap.org/oralhealth/pact

Answer When do the primary (baby) teeth begin to erupt? A. It varies from child to child. B. Around 6 months of age. C. Around 9 months of age. D. Around 12 months of age. E. Around 18 months of age. http://www.aap.org/oralhealth/pact

References 1. Cunha RF, Boer FA et al. Natal and neonatal teeth: review of the literature. Pediatr Dent, 2001; 23(2):158-162. 2. Anderson JE. "Nothing but the tooth”: Dispelling myths about teething. Contemp Pediatr. 2004; 21:75. http://www.aap.org/oralhealth/pact