Final Flashcards
What is the incidence of cleft lip and palate?
1 in 700 live births
What gender has more cleft lips and palates?
Boys
Which side is more affected?
Left.
What are the most common problems affecting the orofacial region when you have clp?
Partial anodontia, supernumerary teeth, malocclusion, malformed teeth.
Who is on the cleft team?
Peds dentist, orthodontitis, OMXS, Plastic surgeon, pediatrician, speech pathologist, psychologist, social worker, geneticist.
When in fetal life does the formation of the nose lip and palate take place?
5th-10th weeks.
What forms the lip?
2 medial nasal swellings and 2 maxillary swellings. It is apart of the intermaxillary segment.
What forms the intermaxillary segment?
Labial component, alveolar segment and primary palate.
What is the cause of a cleft lip and palate?
Exact cause unknown, but is associated with other syndromes.
What is the most common malocclusion class for cleft lip and palate.
Class III. Retardation of MX growth.
Nasal deformity of a cleft lip
Alar cartilage is flared on side of cleft. Columella is pulled toward the non cleft side. Poor underlying bony support for base of nose.
What are ear problems associated with CLP
Predisposed to middle ear infections and poor drainage of the middle ear due to muscle dysfunction. These pts require myringotomy tubes.
Rule of 10’s for timing of surgical repair
10 weeks, 10 lbs, 10 g/dl hemoglobin.
What are the advantages of early closure?
Better palatal and pharyngeal muscle development, ease of feeding, better speech development, better auditory tube function, better hygiene, improved psychologic state of pt and parents.
Early closure disadvantages
More difficult in younger children, scar formation and resulting growth restriction.
At what age do you close a soft palate?
8-18 months.
At what age do you close a hard palate?
May be delayed to allow for growth. You wait until you at least have the eruption of deciduous teeth.
At what age do you close a cleft alveolus?
Usually performed between 6-10 years of age.
Why would you graft the alveolus?
Achieves stability of the arch, preventing collapse of alveolar segments, improves health of dentition, allowing for eruption of canine and lateral incisors, provides for continuity of the piriform rim (supports the ala of the nose), repairs residual oronasal fistula, improving hygiene and speech.
When would you do primary grafting?
Less than 2 years of age. The outcome is poor if it is at the time of lip repair due to abnormal MX development. You can also do it prior to palate repair but after lip repair. It provides reasonable results, but requires very specific protocol.
What is the protocol for primary grafting prior to palate repair but after lip repair?
Only rib graft performed with limited dissection, segments in very close proximity.
When is secondary grafting?
After 2 years of age. Early secondary (2-5 yr) is not supported by literature. Mixed dentition secondary is between ages 6-12 and can be considered early and late (6-8 and 9-12). Late secondary is after the age of 12. Ages 6-10 is the most common.
When is the ideal timing for mixed dentition grafting?
After the eruption of the central incisors and before the eruption of the canine. Less effect on facial growth as there is minimal maxillary growth after the age of 6-7. Generally better cooperation with perioperative and orthodontic care is acceptable. Donor sites have adequate bone for autogenous grafting, eruption of tooth may improve bone volume, enhances health of teeth in area of grafting.
What is the Ideal Patient for grafting?
8-12 years of age. MX canine root 1/2-2/3 developed. Some authors recommend 6-8 yrs so you preserve the lateral incisor, but this is controversial. There is a congenitally missing lateral in 35-60%, but if it is present you can consider it.
Should you use dental or chronologic age?
Use dental age for evaluation of grafting timing!
Factors affecting timing of grafting.
The presence and position of the lateral incisor is important. Degree of rotation or angulation of central incisor as the positioning is a result of the underlying bone and you may need grafting prior to ortho movement. Trauma and mobility of premax segment, social issues, pt. and cleft size, occlusion, need for adjunctive procedures, team dynamics.
Why is the iliac crest good for bone grafting?
Low morbidity and high volume of osteoblastic cells.
Calvarial Bone
Less successful than iliac crest. Less bone.
Mandibular symphysis
Less useful for earlier grafts due to tooth development
Tibia
Can’t be used in developing children.
Rib
Used in primary grafting. (less than 2 years of age)
Allogenic bone graft
Slower revascularization, less predictable in large or bilateral clefts, slower reformation of new bone.
Bone Morphogenic Protein
Off label use, avoids donor site, shows similar results to iliac crest bone grafting, less dimensional support, costly.
Pre-surgical expansion
Controversial, but most authors support it. It is easier prior to grafting due to mobility of segments. There is improved access to the nasal floor and it eliminates traumatic occlusion. Improves post op hygiene.
Post-surgical expansion
Smaller tissue defect to close, improved bone consolidation when bone is put under dynamic load, narrower defect, bone heals more quickly.
Which approach to expansion would you use?
Both are appropriate, you must use clinical judgement.
Why is ortho movement of teeth next to the graft not typically desired?
It increases the chance of moving teeth into the cleft. Osseous cleft is usually larger than the soft tissue defect.
What are the goals of cleft surgery?
Closure of the nasal floor, closure of palatal and labial fistula, maintain keratinized tissue around teeth, closure without tension, avoid shortening of the vestibule.
What is the surgical technique?
Advancing buccal and palatal flaps
Post Graft Management
Monitor eruption of canine, occasionally needs surgical exposure. If laterals are missing, decide whether space maintenance or canine substitution is best. May need further grafting to facilitate implant placement.
What is the Bergland Scale?
The permanent canine must be erupted, there are 4 categories: Type I: 0-25% resorption. Type II: 25-50% resorption. Type III: 50-75% resorption. Type IV: 75-100% resorption with no residual bony bridge.
What is the Chelsea Scale?
Type A: Bone at CEJ with 75% of root covered.
Type B: Bone at CEJ with 25% of root covered.
Type C: 75% of roots covered with bone.
Type D: 50% of roots covered with bone.
Type E: Presence of bone tissue bridge.
Type F: 25% of roots covered with bone.
What is your initial assessment of a trauma patient? (Primary Survey)
Airway, breathing, circulation, disability (life threatening injuries and neurologic status), exposure. Basically ABC’s of CPR.
What is the secondary survey of a trauma pt.
Thorough examination. Most head and neck injuries are accomplished during this time. Systemic approach.
What type of radiographs do you need for dentoalveolar injuries?
PA films, pano, CT scan. May need to take at different angles and may need to take of soft tissues.
Crown Craze or Crack-Crown Infraction
Incomplete fracture of enamel with no loss of tooth structure.
Uncomplicated Crown Fracture
Confined to enamel or enamel with dentin. NO pulp
Complicated Crown Fracture
Enamel, dentin and exposed pulp.
Uncomplicated Crown/Root Fracture
Enamel, dentin, cementum. NO pulp
Complicated Crown/Root Fracture
Enamel, dentin, cementum, and pulp.
Horizontal Root Fracture
Dentin, cementum with pulp exposure.
Concussion
Sensitivity to percussion with no loosening of tooth.
Subluxation
Tooth is loosened, but not displaced.
Luxation
Dislocation or partial avulsion of the tooth. Tooth is displaced without accompaning communication or fracture of the socket.
Avulsion
Tooth lost from socket.
How do you manage an enamel fracture?
Smooth rough edges or repair with composite. Test vitality initially and again in 6-8 weeks.
How do you manage an uncomplicated crown fracture?
Composite restoration. Test vitality initially and then again in 6-8 weeks. Check for luxation. Better prognosis for tooth if it hasn’t been luxated due to blood supply.