Periapical Granuloma
Etiology: The result of necrotic pulp tissue and by-products resulting from an inflammatory process that has damaged the tissue at the apex of the tooth.
Epidemiology: Any age group may be affected by a periapical granuloma, and there is equal gender distribution. IT is caused by damage to the tooth structure, anyone may be affected.
Pathogenesis: The diseased tissue from the tooth causes chronically inflamed granulation tissue to accumulate in the apical area of the tooth. The mobilizations of host defense mechanisms kill the invading microorganisms and also destroy normal tissue components, inducing bone resorption.
Perioral and intraoral characteristics: The periapical granuloma is the accumulation of granulation tissue that is focused a the apical area of a nonmetal tooth.
Distinguishing characteristics: Seen radiographically as a round or ovoid translucent lesion. The size of the lesion may vary from several millimeters to larger, more advanced lesions encompassing larger areas.
Significant microscopic features: Granuloma are those of inflamed granulation tissue. The inflammatory response consist of a defense mechanism in response to bacterial components.
Dental implications: Vitality testing is crucial, since the tooth will test nonmetal when obvious radiographic evidence is apparent. If the tooth is nonmetal, endodontic treatment is needed.
Differential diagnosis: In a nonvital tooth, a radicular cyst would be considered.
Treatment and prognosis: Extraction of the nonmetal tooth or endodontic treatment is the usual procedure for granulomas. The prognosis is good if all the granuloma is removed.
Pg. 464-465

Radicular Cyst
Etiology: Always associated with the root of a nonmetal tooth, and the common causes are caries, trauma such as fracture or injury to the tooth, or periodontal disease.
Epidemiology: The radicular cyst is the most commonly occurring inflammatory cyst of the jaws, with most reported in the maxillary region.
Pathogenesis: Radicular cysts are derived from the rests of Malaise, found in developing tooth structure of the periodontal ligament.
Perioral and intraoral characteristics: The radicular cyst may be found in any region of the mandible and maxilla, but it generally favors the maxillary anterior region at the apex of a nonmetal tooth.
Distinguishing characteristics: The radicular cyst cannot be differentiated from the periapical granuloma by a radiograph.
Significant microscopic features: The epithelial lining of the radicular cyst is composed of nonkeratinized-stratified squamous epithelium varying in thickness.
Dental implications: Failure to remove the radicular cyst completely results in recurrence.
Differential diagnosis: Periapical granuloma, central giant cell granuloma, newly developing periapical cementoozseous dysplasia, and traumatic bone cysts.
Treatment and prognosis: Involves several options: removal by extraction, surgery with curettage, and root canal therapy.
Oral medicine considerations: Failure to remove the entire cyst results in what is called a residual cyst.
Pg. 465-467

Aneurysmal Bone Cyst
Etiology: Considered a pseudocyst, in that it appears as a cyst, but unlike the epithelium-lined true cyst, the aneurysmal bone cyst does not have the epithelium-lined lumen.
Epidemiology: Found in individuals less than 30 years of age, with a peak incidence in the second decade of life.
Pathogenesis: Unclear about whether there is a preexisting lesion or whether the bone cyst develops because of dilated vessels.
Extraoral characteristics: Extraoral swelling is reported in extensive lesions.
Perioral and intraoral characteristics: Swelling without pain. Radiographic features of an aneurysmal bone cyst include a unilocular or mulitlocular lesion, described as having a soap bubble appearance. Thinning and expansion of the cortical bone may be seen. Ballooning and distention of the cortical bone is often recognized.
Distinguishing characteristics: Exhibit some key radiographic appearances. The lesion presents as expansile, with thin peripheral bone that is blood filled, without the presents as expansile, with thin peripheral bone that is blood filled, without the presence of what is called bruit, thrill, or pulse pressure.
Significant microscopic features: Composed of immature connective tissue and scattered multinucleate giant cells.
Dental implications: May cause the teeth to become displaced or loose because of bone expansion.
Differential diagnosis: Odontogenic keratocyst, central giant cell granuloma, ameloblastic fibroma, and ameloblastoma.
Treatment and prognosis: Excision and curettage are treatments of choice. When the lesion is removed completely, the prognosis is good.
Oral medicine consideration: Questions to ask patient when assessing the condition.
Pg. 467-468

Traumatic Bone Cyst
Etiology: Caused by trauma.
Epidemiology: May occur in any bone such as the femur and humerus. Found in the 10-20 age group.
Pathogenesis: Thought to be a hematoma, probably induced by trauma, which does not heal and subsequently liquefies and becomes a cyst.
Extraoral characteristics: May cause swelling if the lesion is large enough or has existed long enough.
Perioral and intraoral characteristics: Increased swelling in the mouth may be observed, but pain is not usually a factor. The lesions are discovered on radiographs, with he patient reporting no pain or other symptoms.
Distinguishing characteristics: When questioning the patient about a radiolucent lesion, the patient will often report previous trauma to the area in question. When the lesion is opened, invariably only an empty cavity is found although it can occasionally be full of blood.
Significant microscopic features: Epithelial component is not present, since there is no epithelial lining.
Dental implications: May continue to expand and increase in size when not detected in the early stages.
Differential diagnosis: Cases have been reported of florid cementoozseous dysplasia.
Treatment and prognosis: Opening the cyst. Once the blood cavity is emptied, the bone will repair itself over time.
Oral medicine considerations: Questions to ask when talking to the patient.
Pg. 468-469

Cementoosseous Dysplasia

• discovered during a radiographic examination
• pt will not report any sensitivity or discomfort
• three types of lesions: periapical cementoosseous dysplasia, focal cementoosseous dysplasia, and florid cementoosseous dysplasia.
  Pg. 469

Periapical Cementoosseous Dysplasias
Etiology: Unknown, but they are considered to be a dysplastic process affecting cells in the PDL and their ability to remodel bone and cementum.
Epidemiology: Process that is not contagious and is considered benign. Occurrence is usually in the over 40-year-old age group and occurs with middle-aged women.
Pathogenesis: Some researchers suggest they are developmental and related to a defect in the bone and/or cementum remodeling in adulthood, and others consider them only reactionary type entities.
Perioral and intraoral characteristics: Patient is usually asymptomatic, and the lesions are discovered on routine radiographs.
Distinguishing characteristics: Periapical COD occurs at the apex of vital teeth, with a propensity for the anterior mandibular teeth.
Significant microscopic features: Fibrous connective tissue that can be seen with bone and cementum in varying quantities.
Dental implications: The vitality of the tooth is important, since the tooth tests vital with periapical COD.
Differential diagnosis: Odontoma, and cementoossifying fibroma.
Treatment and prognosis: Requires no treatment, and extraction or surgery is not required since the teeth remain vital.
Pg. 469

Osteomyelitis: Acute and Chronic Forms
Etiology: Inflammation in bone. A periapical abscess is most often the cause of the acute form of osteomyelitis.
Method of transmission: May have several infectious organisms involved in the disease process.
Epidemiology: Can occur in any age group.
Pathogenesis: Staphyloccocci and streptococci are the bacteria most commonly involved in the origin of osteomyelitis.
Extraoral characteristics: Lymphadenopathy, fever, and pain are often symptoms of this and are especially noted int he acute form.
Perioral and intraoral characteristics: An acute infection may not produce the destruction that the chronic form produces because it has not been present in long enough to create bone damage.
Distinguishing characteristics: The radiographic appearance is a distinguishing characteristic.
Significant microscopic features: Loss of osteocytes from their lacunae and bacterial colonization with the presence of predominately necrotic bone.
Dental implications: The patient may have pain and lymphadenopathy. Addressing the cause of this is paramount.
Differential diagnosis: The pain, lymphadenopathy, and radiographic appearance usually indicate osteomyelitis.
Treatment and prognosis: Drainage and antibiotics are needed to treat the acute form of this. The chronic form is more difficult to manage because of necrosis.
Pg. 471

Adenomatoid Odontogenic Tumor
Etiology: Encapsulated benign epithelial odontogenic tumor.
Epidemiology: Usually seen between the ages of 5 and 30 years. Most are under 20.
Pathogenesis: Benign epithelial tumor with a dense fibrous connective tissue capsule, which usually does not recur once adequately removed.
Extraoral characteristics: Swelling in the facial area is sometimes reported, causing flaring of the nasolabial fold and extending beyond the facial contour.
Perioral and intraoral characteristics: As the tumor expands and increases in size, there may be root displacement and a bony hard expansion with an eggshell cracking appearance over the protrusion.
Distinguishing characteristics: The microscopic features of this tumor depict distinguishing characteristics. The glandular or duct-like features forming rosette pattern clearly differentiates the AOT from other lesions.
Significant microscopic features: As mentioned above, the rosettes and duct-like features are very characteristic of this tumor. These patterns are composed of duct-like structures of columnar epithelial cells and consist of polyhedral spindle cells organized in sheets and lobules.
Dental implications: Facial asymmetry is one of the first signs to be noticed by the patient as the tumor increases in size.
Differential diagnosis: Dentigerous cyst, calcifying epithelial odontogenic tumor, ameloblastoma, and odontogenic keratocyst.
Treatment and prognosis: Complete removal of the tumor is necessary, and the prognosis is excellent without any recurrence.
Oral medicine considerations: Specific questions to ask to obtain information from the patient.
Pg.483-485

Odontogenic Myxoma
Etiology: Derived from odontogenic ectomesenchyme.
Epidemiology: Occurs in the 10-30 year old age group.
Pathogenesis: Benign neoplasms that are capable of rapid growth and are very persistent.
Extraoral characteristics: Swelling may occur depending upon the size.
Perioral and intraoral characteristics: Radiographically the tumors can be unilocular or multilocular, and the radiolucencies may have a scalloped appearance. Have also been described as having a "step ladder" or "honey-combed" appearance. The margins may be well defined or they may be diffuse.
Significant microscopic features: Stellate-shaped cells and fine collagen fibrils. The specimen is gelatinous and pulp-like.
Dental implications: Enlarged dental follicles or the dental papilla of a developing tooth may be mistaken for the myxomas upon microscopic examination.
Differential diagnosis: Odontogenic fibroma, ameloblastoma, and hemangioma of bone.
Treatment and prognosis: Removed surgically, usually with a wide margin of normal bone.
Pg. 485

Ameloblastic Fibroma
Etiology: Originate from odontogenic ectomesenchyme and odontogenic epithelium.
Epidemiology: Seen infrequently, and are slow growing and small in size.Seen in early life before the age of 20.
Pathogenesis: Composed of neoplastic epithelium and neoplastic myxomatous connective tissue and are usually associated with third molars.
Extraoral characteristics: Some external swelling may be present.
Perioral and intraoral characteristics: No pain with any swelling that may occur. Ameloblastic fibroma has potential for extensive growth causing jaw expansion.
Distinguishing characteristics: Unusual and highly diagnostic.
Significant microscopic features: Composed of long strands and islands of odontogenic epithelium set in an immature cellular matrix resembling the dental papilla or developing dental pulp.
Dental implications: Asymptomatic.
Differentail diagnosis: Ameloblastoma, odontogeic myxoma, dentigerous cyst, odontoma, dentigerous cyst, myxoma, odontogeic keratocyst, and central giant cell granuloma.
Treatment and prognosis: Conservative excision is the treatment of choice. Recurrence is seen in approximately 20% of cases.
Oral medicine considerations: Careful dialogue with the patient is necessary since long-term follow-up is important.
Pg. 485-486

Langerhans Cell Disease: Langerhans Cell Histoiocytosis
Etiology: Unknown.
Epidemiology: Involves young adults and children.
Pathogenesis: Monostotic or polyostotic eosinophilic granuloma occurs in young adults or adults. Bone lesions are present and exhibit as well defined radiolucent lesions. Hand-Schuller-Christian disease is termed multifocal eosinophilic granuloma and affects children, under 5 years and results in diabetes insipidus, punched-out lesions, and ophthalmos. Letterer-Size disease, infants are affected by this, a rash may be the first sign of the disorder.
Extraoral characteristics: Poor healing is common with Langerhans cell disease, dermatologic conditions may be evident, and all bones of the body may be affected.
Perioral and intraoral characteristics: May involve one or more multiple bones in the body, including the bones around the teeth, contributing to loosening. Tenderness, pain, and swelling are common complainants.
Distinguishing characteristics: Premature loosening and exfoliation of teeth in children.
Significant microscopic features: Involve large histiocytoid cells mixed with eosinophils.
Dental implications: Lesions that occur periapically can be confused with periapical cyst or granulomas. Tooth vitality would still be present.
Differential diagnosis: Juvenile periodontitis, Leukemia, malignant neoplasms, and multiple myeloma.
Treatment and prognosis: The treatment depends upon the involvement of the disease and the age of the patient. Conservative surgical treatment is sometimes the only treatment.
Oral medicine considerations: The bone of the oral cavity may be affected and dental issues usually result.
Pg. 486-488