The most important diagnostic test to differentiate between an acute periapical abscess and a phoenix abscess is: PGCEE MDS 2022

 # The most important diagnostic test to differentiate between an acute periapical abscess and a phoenix abscess is: 

a) Pulp testing

b) Radiographs

c) History

d) Percussion

The correct answer is B. Radiographs.

Phoenix abscess is an acute inflammatory reaction superimposed on an existing chronic lesion, such as a cyst or granuloma. The exacerbation of a chronic lesion is most commonly associated with the initiation of root canal therapy in a completely asymptomatic tooth. In such a tooth, radiographs show well-defined periradicular lesions.

The deciduous tooth which does not have a resemblance to any other teeth is: PGCEE MDS 2022

 # The deciduous tooth which does not have a resemblance to any other teeth is:

a) Maxillary first molar 

b) Mandibular first molar

c) Maxillary 2nd molar 

d) Mandibular canine

The correct answer is B. Mandibular first molar.

The deciduous mandibular first molar is unique in that it has a crown form unlike that of any permanent tooth. It does, however, have two strong roots, one mesial and one distal—an arrangement similar to that of a mandibular permanent molar. These two primary teeth, the maxillary and mandibular first molars, differ from any teeth in the permanent set when crown forms are compared, in particular.

The microorganism most commonly cultured from a chronic bilateral ulcer at the corner of the mouth: PGCEE MDS 2022

 # The microorganism most commonly cultured from a chronic bilateral ulcer at the corner of the mouth:

a) Mucor 

b) Candida

c) Treponema 

d) Aspergillus

The correct answer is B. Candida. 

Angular cheilitis (AC) is inflammation of one or both corners of the mouth. Often the corners are red with skin breakdown and crusting. It can also be itchy or painful. The condition can last for days to years. Angular cheilitis is a type of cheilitis (inflammation of the lips).

Angular cheilitis can be caused by infection, irritation, or allergies. Infections include fungi such as Candida albicans and bacteria such as Staph. aureus. Irritants include poorly fitting dentures, licking the lips or drooling, mouth breathing resulting in a dry mouth, sun exposure, overclosure of the mouth, smoking, and minor trauma. Allergies may include substances like toothpaste, makeup, and food. Often a number of factors are involved. Other factors may include poor nutrition or poor immune function. Diagnosis may be helped by testing for infections and patch testing for allergies.

Phlegmon is a: PGCEE MDS 2022

 # Phlegmon is a:

a) Sexually transmitted disease

b) Type of cellulitis

c) Type of osteomyelitis 

d) Venereal disease

The correct answer is B. Type of  cellulitis.

Cellulitis or Phlegmon is a diffuse inflammation of soft tissues that\ is not circumscribed or confined to one area, but which, contrary to the abscess, tends to spread through tissue spaces and along fascial planes. This type of reaction occurs due to infection by microorganisms that produce significant amounts of streptokinase, hyaluronidase (the spreading factor of Duran-Reynolds) and fibrinolysins, which act to breakdown or dissolve hyaluronic acid, the universal intercellular cement substance, and fibrin. Streptococci are particularly potent producers of hyaluronidase and are therefore a common causative organism in cases of cellulitis. Streptococci in their growth phase consume local oxygen and metabolize nutrients to produce an acidic environment, which is conducive to the subsequent growth of anaerobic microbes. The anaerobes such as Prevotella and Porphyromonas species destroy collagen.