cleft lip & cleft palate

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At the end of this lecture, students should be able to: Develop an understanding terms Cleft lip & Palate Develop an understanding of incidence of the condition Describe the etiology and pathogenesis Describe classification and dental implications

TRANSCRIPT

Learning Objectives

At the end of this lecture, students should be able to:

• Develop an understanding terms Cleft lip & Palate

• Develop an understanding of incidence of the condition

• Describe the etiology and pathogenesis

• Describe classification and dental implications

Contents

1. Cleft Lip & Palate

2. Incidence

3. Causes

4. Method of Transmission

5. Pathogenesis

6. Normal Process

7. Classification

8. Dental Implications

9. References

Cleft Lip & Palate

The term cleft lip & palate is commonly used to represent two types of malformation• cleft lip with or without cleft palate (CL/P)(fig.1)

• cleft palate (CP) (fig.2)

dromic cases of clefting that account for about 70% ofclefts is unknown at this time (NIDCR, 2006).

Method of Transmission: The method of transmis-sion depends on the specific cause of the clefting.Multifactorial clefts can exhibit evidence of autosomal dom-inant, autosomal recessive, and sex-linked inheritance pat-terns or they may be the result of a spontaneous mutation ormutations in one or more genes. While genetic factors ap-pear to predispose an individual for clefting, environmentalfactors act as a trigger to cause development of the cleft.

Epidemiology: Orofacial clefting of some type occurs inapproximately 1 of every 500 to 550 live births in the UnitedStates. The frequency and cause of oral clefting is highly re-lated to the sex of the individual and the type of cleft in-volved. Females who have a bilateral cleft have the greatestnumber of genetic influences and the lowest number of en-vironmental factors, and males with a unilateral cleft havethe lowest number of genetic influences and the highestnumber of environmental factors (Tolarova, July 2005).

Pathogenesis: Cleft lip/palate occurs when there isincomplete or no fusion of the palate, premaxilla, and re-lated soft tissues during the 6th to 8th week of embry-ologic development. Multifactorial inheritance impliesthat changing something in the environment will eitherinterfere with the development of a cleft or enhance the

probability that a genetic predisposition will actually re-sult in clefting.

Extraoral Characteristics: Not applicable

Perioral and Intraoral Characteristics: Refer toFigure 6.24 for examples of cleft lip, cleft palate, and cleft

CHAPTER 6 • DEVELOPMENTAL, HEREDITARY, AND CONGENITAL DISORDERS 139

Examples of disorders that are commonly considered tobe caused by multifactorial inheritance.

ADULTS

HypertensionAtherosclerosisType II diabetesPsoriasisSchizophreniaAnkylosing spondylitisGoutCancerObesity OsteoporosisParkinson’s diseaseAlcoholism

CHILDREN

Pyloric stenosisCleft lip and palateCongenital heart diseaseCongenital hip dislocation

Box 6.7 MULTIFACTORIAL INHERITANCE

Figure 6.24. Oral clefting. A. Bilateral cleft of the lip andpalate. (From Rubin E, Farber JL. Pathology. 3rd ed.Philadelphia: Lippincott Williams & Wilkins, 1999.) B. Cleftof the hard and soft palates. (Courtesy of R Chase.) C.Unilateral cleft of the upper lip. (Courtesy of R Chase.)

96322_ch 06 9/12/07 1:46 PM Page 139

Bilateral cleft of lip & palate(fig.1)

dromic cases of clefting that account for about 70% ofclefts is unknown at this time (NIDCR, 2006).

Method of Transmission: The method of transmis-sion depends on the specific cause of the clefting.Multifactorial clefts can exhibit evidence of autosomal dom-inant, autosomal recessive, and sex-linked inheritance pat-terns or they may be the result of a spontaneous mutation ormutations in one or more genes. While genetic factors ap-pear to predispose an individual for clefting, environmentalfactors act as a trigger to cause development of the cleft.

Epidemiology: Orofacial clefting of some type occurs inapproximately 1 of every 500 to 550 live births in the UnitedStates. The frequency and cause of oral clefting is highly re-lated to the sex of the individual and the type of cleft in-volved. Females who have a bilateral cleft have the greatestnumber of genetic influences and the lowest number of en-vironmental factors, and males with a unilateral cleft havethe lowest number of genetic influences and the highestnumber of environmental factors (Tolarova, July 2005).

Pathogenesis: Cleft lip/palate occurs when there isincomplete or no fusion of the palate, premaxilla, and re-lated soft tissues during the 6th to 8th week of embry-ologic development. Multifactorial inheritance impliesthat changing something in the environment will eitherinterfere with the development of a cleft or enhance the

probability that a genetic predisposition will actually re-sult in clefting.

Extraoral Characteristics: Not applicable

Perioral and Intraoral Characteristics: Refer toFigure 6.24 for examples of cleft lip, cleft palate, and cleft

CHAPTER 6 • DEVELOPMENTAL, HEREDITARY, AND CONGENITAL DISORDERS 139

Examples of disorders that are commonly considered tobe caused by multifactorial inheritance.

ADULTS

HypertensionAtherosclerosisType II diabetesPsoriasisSchizophreniaAnkylosing spondylitisGoutCancerObesity OsteoporosisParkinson’s diseaseAlcoholism

CHILDREN

Pyloric stenosisCleft lip and palateCongenital heart diseaseCongenital hip dislocation

Box 6.7 MULTIFACTORIAL INHERITANCE

Figure 6.24. Oral clefting. A. Bilateral cleft of the lip andpalate. (From Rubin E, Farber JL. Pathology. 3rd ed.Philadelphia: Lippincott Williams & Wilkins, 1999.) B. Cleftof the hard and soft palates. (Courtesy of R Chase.) C.Unilateral cleft of the upper lip. (Courtesy of R Chase.)

96322_ch 06 9/12/07 1:46 PM Page 139

cleft of the hard & soft palates(fig.2)

dromic cases of clefting that account for about 70% ofclefts is unknown at this time (NIDCR, 2006).

Method of Transmission: The method of transmis-sion depends on the specific cause of the clefting.Multifactorial clefts can exhibit evidence of autosomal dom-inant, autosomal recessive, and sex-linked inheritance pat-terns or they may be the result of a spontaneous mutation ormutations in one or more genes. While genetic factors ap-pear to predispose an individual for clefting, environmentalfactors act as a trigger to cause development of the cleft.

Epidemiology: Orofacial clefting of some type occurs inapproximately 1 of every 500 to 550 live births in the UnitedStates. The frequency and cause of oral clefting is highly re-lated to the sex of the individual and the type of cleft in-volved. Females who have a bilateral cleft have the greatestnumber of genetic influences and the lowest number of en-vironmental factors, and males with a unilateral cleft havethe lowest number of genetic influences and the highestnumber of environmental factors (Tolarova, July 2005).

Pathogenesis: Cleft lip/palate occurs when there isincomplete or no fusion of the palate, premaxilla, and re-lated soft tissues during the 6th to 8th week of embry-ologic development. Multifactorial inheritance impliesthat changing something in the environment will eitherinterfere with the development of a cleft or enhance the

probability that a genetic predisposition will actually re-sult in clefting.

Extraoral Characteristics: Not applicable

Perioral and Intraoral Characteristics: Refer toFigure 6.24 for examples of cleft lip, cleft palate, and cleft

CHAPTER 6 • DEVELOPMENTAL, HEREDITARY, AND CONGENITAL DISORDERS 139

Examples of disorders that are commonly considered tobe caused by multifactorial inheritance.

ADULTS

HypertensionAtherosclerosisType II diabetesPsoriasisSchizophreniaAnkylosing spondylitisGoutCancerObesity OsteoporosisParkinson’s diseaseAlcoholism

CHILDREN

Pyloric stenosisCleft lip and palateCongenital heart diseaseCongenital hip dislocation

Box 6.7 MULTIFACTORIAL INHERITANCE

Figure 6.24. Oral clefting. A. Bilateral cleft of the lip andpalate. (From Rubin E, Farber JL. Pathology. 3rd ed.Philadelphia: Lippincott Williams & Wilkins, 1999.) B. Cleftof the hard and soft palates. (Courtesy of R Chase.) C.Unilateral cleft of the upper lip. (Courtesy of R Chase.)

96322_ch 06 9/12/07 1:46 PM Page 139

Unilateral cleft of lip(fig.3)

cleft of lip & palate(fig.4)

Bifid uvula(fig.5)

Cleft lip, cleft palate, and the combination of cleft lip and palate are considered to have a multifactorial cause, including both environmental and genetic elements.

incidence

• common congenital malformation

• reported incidence varies from 1 in 500 to 1 in 2500 live births

• male:female 2:1

• Asian population have higher incidence compared to the caucasian population

Causes

• Oral clefts have been linked to genes l o c a t e d o n m o r e t h a n s e v e r a l chromosomes including 1, 2, 4, 6, and 19, among others

Causes

• maternal smoking (especially more than 20/day) and exposure to passive smoke

• Drugs: Accutane, phenytoin, warfarin ethanol

• maternal folic acid deficiency

• ingest large quantities of Vit A

Method of Transmission

• Depends on the specific cause of the clefting.

• Multifactorial clefts can exhibit evidence of autosomal dominant, autosomal recessive, and sex-linked inheritance patterns

• spontaneous mutation or mutations in one or more genes.

Method of Transmission

• If one of the parent has a cleft lip, his/her child face a risk of 20%

• If their is one child with cleft lip, the following child faces risk of 14%

• A non cleft parent with a cleft lip faces a risk of 4% for the following child

Pathogenesis

• The face and facial structures are formed out of three plates, each migrating toward a meeting point in the middle area of the face.

• The facial structures of the orbicularis muscle form the lip. They are joined at the philitrum lines.

• join by 4th week of pregnancy

• The palate is then formed out of the structure that begins as the tongue and palate.

• Between the fourth and the eighth weeks of gestation, the tongue drops down and the palatal segments then move from the sides and toward the middle, fusing in the center.

• A cleft, therefore, is not something that is formed, so much as it is something that does not form.

Normal Process

6 Weeks• Maxillary process

• Lateral nasal process

• Median nasal processThese three processes join and fuse to form the primary palate

Normal Process

7 WeeksMedian nasal process and maxillary process have fused creating upper lip and anterior maxillary alveolus

Normal Process

8 WeeksComplex totally fused and mesodermal migration completed Tongue, which has been postured superiorly between lateral palatal shelves of maxilla, moves inferiorly allowing palatal processes to grow toward midline and fuse, form nasopalatine foramen to uvula

Normal Process

11 WeeksTotal palatal closure

Classification

• The Veau Classification system (table.1)

• The Striped-Y Classification system (fig.6)

The Veau Classification system

Class Description

I Soft palate only

II Hard & soft palate to the incisive foramen

III Complete unilateral of soft, hard, lip, & alveolar ridge

IV Complete bilateral of soft, hard, and/or lip and alveolar ridge

These descriptions can be modified with the words incomplete, right, left, one/third, and so on.

(Table.1)

The Striped-Y Classification system

First East Indian International Cleft Surgery Workshop

25

I

N

T

R

O

D

U

C

T

I

O

N

The variation in clefts is considerable.A good way to record a cleft lip is byphotography. A better way to record apalatal cleft is to fill in the followingfigure with stripes and dots.

R L

R L

R L

R L

Fig. 2Cleft palate

Fig. 3Left-sided unilateral completecleft lip and palate

Fig. 4Bilateral complete cleft lipand palate

Fig. 5Bilateral-right incomplete, leftcomplete-cleft lip and primarypalate

R L

Primarypalate

Alveolus

Lip

Foramenincisivum

SpinaeSoftpa late

Vome

r

1270-8597-13528 Labio leporin** 18/9/03 09:14 Página 25

(fig.6)

First East Indian International Cleft Surgery Workshop

25

I

N

T

R

O

D

U

C

T

I

O

N

The variation in clefts is considerable.A good way to record a cleft lip is byphotography. A better way to record apalatal cleft is to fill in the followingfigure with stripes and dots.

R L

R L

R L

R L

Fig. 2Cleft palate

Fig. 3Left-sided unilateral completecleft lip and palate

Fig. 4Bilateral complete cleft lipand palate

Fig. 5Bilateral-right incomplete, leftcomplete-cleft lip and primarypalate

R L

Primarypalate

Alveolus

Lip

Foramenincisivum

SpinaeSoftpa late

Vome

r

1270-8597-13528 Labio leporin** 18/9/03 09:14 Página 25

Cleft palate(fig.7)

First East Indian International Cleft Surgery Workshop

25

I

N

T

R

O

D

U

C

T

I

O

N

The variation in clefts is considerable.A good way to record a cleft lip is byphotography. A better way to record apalatal cleft is to fill in the followingfigure with stripes and dots.

R L

R L

R L

R L

Fig. 2Cleft palate

Fig. 3Left-sided unilateral completecleft lip and palate

Fig. 4Bilateral complete cleft lipand palate

Fig. 5Bilateral-right incomplete, leftcomplete-cleft lip and primarypalate

R L

Primarypalate

Alveolus

Lip

Foramenincisivum

SpinaeSoftpa late

Vome

r

1270-8597-13528 Labio leporin** 18/9/03 09:14 Página 25

Left-sided unilateral complete cleft lip and palate(fig.8)

First East Indian International Cleft Surgery Workshop

25

I

N

T

R

O

D

U

C

T

I

O

N

The variation in clefts is considerable.A good way to record a cleft lip is byphotography. A better way to record apalatal cleft is to fill in the followingfigure with stripes and dots.

R L

R L

R L

R L

Fig. 2Cleft palate

Fig. 3Left-sided unilateral completecleft lip and palate

Fig. 4Bilateral complete cleft lipand palate

Fig. 5Bilateral-right incomplete, leftcomplete-cleft lip and primarypalate

R L

Primarypalate

Alveolus

Lip

Foramenincisivum

SpinaeSoftpa late

Vome

r

1270-8597-13528 Labio leporin** 18/9/03 09:14 Página 25

Bilateral complete cleft lip and palate(fig.9)

First East Indian International Cleft Surgery Workshop

25

I

N

T

R

O

D

U

C

T

I

O

N

The variation in clefts is considerable.A good way to record a cleft lip is byphotography. A better way to record apalatal cleft is to fill in the followingfigure with stripes and dots.

R L

R L

R L

R L

Fig. 2Cleft palate

Fig. 3Left-sided unilateral completecleft lip and palate

Fig. 4Bilateral complete cleft lipand palate

Fig. 5Bilateral-right incomplete, leftcomplete-cleft lip and primarypalate

R L

Primarypalate

Alveolus

Lip

Foramenincisivum

SpinaeSoftpa late

Vome

r

1270-8597-13528 Labio leporin** 18/9/03 09:14 Página 25

Bilateral-right incomplete, left complete-cleft lip and primary palate

(fig.10)

Dental Implications

• The dental implications of cleft lip and/or palate depend on the number of dental abnormalities present and the stage of treatment.

• The dentist play an important role in managing the care of the individual with a cleft lip and/or palate through education and preventive dental hygiene therapy.

• Numerous surgical and other medical and dental treatments are necessary to correct cleft lip/palate. The surgeries are scheduled starting at about 3 months of age & ending at about 1 year to correct simple clefts.

References

• Dr. B. Sudarshan & Dr. Bhanu Murthy, “Plástikos - Cleft Surgeons & Doctors - Smile Train Partners” in First East Indian International Cleft Surgery Workshop, 2003. http://medpro.smiletrain.org.uk/library/images/WS-India-Manual.pdf

• Leslie DeLong, Nancy W. Burkhart, “Developmental, Hereditary and Congenital Disorders” in General Oral Pathology for Hygienists, 1st Edition, Lippincott Williams and Wilkins, 2008 pp 110-146.

• Development of Face, Interactive guide: http://www.indiana.edu/~anat550/hnanim/face/face.html

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