Osseous Defects

Question 1

By definition, what is an osseous defect?

Answer 1

A concavity or deformity in alveolar bone involving one or more teeth

Question 2

What do you use to diagnose/evaluate an osseous defect?

Answer 2

Radiographs and probing the area in both horizontal and vertical aspects

Question 3

What are three classifications for infrabony defects?

Answer 3

three-wall, two-wall, one-wall

Question 4

What bone has resorbed in a three-wall infrabony defect?

Answer 4

Either the mesial or distal bone (adjacent to a tooth’s root)

Question 5

Which wall is most common to be missing in a two-wall infrabony defect?

Answer 5

The facial wall because there is less bone on that side of the alveolar ridge

Question 6

What are the likely sides to see comprising a one-wall defect?

Answer 6

Mesial/distal wall, and rarely you’ll see just a lingual wall

Question 7

What is the most important step in trying to regenerate bone in an infrabony defect?

Answer 7

Getting all surfaces of the defect cleaned of bacteria/disease

Question 8

What is a circumferential 3-wall defect?

Answer 8

A three wall defect that wraps around half of a tooth

Question 9

Does a narrow or wide defect have a better prognosis?

Answer 9

Narrow - blood clot stays better

Question 10

Is prognosis better with a deep or shallow osseous defect?

Answer 10

Deep - better supports blood clot

Question 11

What is the most common bony defect?

Answer 11

interdental craters

Question 12

What kind of infrabony defect is an interdental crater?

Answer 12

A two-wall because it only has the facial and lingual walls made of bone (other walls are adjacent roots)

Question 13

Give some examples for two-wall defects.

Answer 13

Interdental crater, two-wall hemiseptum

Question 14

What is the most commonly seen one-wall defect, and why?

Answer 14

Hemiseptum (interdental bone is the one wall), and it can be caused by people flossing too aggressively

Question 15

Define osseous surgery.

Answer 15

A procedure which aims to eliminate deformities caused by periodontal disease or other related factors, such as exostosis and tooth supraeruption.

Question 16

What are the two basic types of osseous surgery?

Answer 16

Subtractive (resective) and Additive (regenerative)

Question 17

List five options for osseous surgery.

Answer 17

osseous recontouring, induce regeneration of bone, root resection via osseous resection, maintenance of pockets caused by bony defects, and tooth extraction

Question 18

What is the number one reason preventing a patient from having osseous surgery?

Answer 18

Socioeconomic factors

Question 19

What’s the difference between osteoplasty and ostectomy?

Answer 19

osteoplasty = reshaping the bone without removing tooth-supporting bone
ostectomy = removal of tooth-supporting bone

Question 20

Name five therapeutic determinants for osseous surgery.

Answer 20

depth of defect, width of defect’s mouth, topography, number of walls, and configuration of adjacent tooth surfaces

Question 21

What’re some objectives of osseous resection?

Answer 21

Reshaping marginal bone to resemble natural, healthy bone; smooth bone to induce gingival regeneration; create easier cleanable areas; allow for better flap approximation; crown lengthening

Question 22

What three things determine the degree of scalloping of gingiva?

Answer 22

CEJ, convexity of teeth, and tooth position in the alveolar bone

Question 23

If the osseous crest is ≤5mm from the contact point between adjacent teeth, what is the likelihood that the papilla will fully regenerate?

Answer 23

%

Question 24

Gingiva will heal according to… ?

Answer 24

same anatomic concepts as in healthy gingiva

Question 25

Give some indications for osseous resection?

Answer 25

Shallow infrabony defects (1-2mm deep); incipient and shallow furcation invasions; unnatural bony architecture (like tori, etc); contouring of bone

Question 26

What are some contraindications for osseous resection?

Answer 26

if its an esthetic area, an isolated deep pocket, have advanced periodontitis, or near certain anatomic factors, high caries risk, or serious systemic condition

Question 27

What kinds of anatomic factors should you avoid with osseous resection?

Answer 27

Ascending ramus, external oblique ridge, maxillary sinus, adjacent to flat palate

Question 28

What are the four general steps to osseous recontouring?

Answer 28

vertical grooving, radicular blending, flattening interproximal bone, gradualize marginal bone

Question 29

Why would you do radicular blending?

Answer 29

to provide a smooth surface for good flap adaption

Question 30

When should you flatten interproximal bone when recontouring?

Answer 30

When the interproximal bone levels vary horizontally

Question 31

What happens if you fail to remove discrepancies on the gingival line angles (widow’s peak)?

Answer 31

The tissue rises to a higher level than the bone you recontoured in the interdental area