LOCAL FACTORS IN COMPLETE DENTURE

  1. Broad square ridges devoid of undercuts and bony abnormalities.
  2. Definite cuspid eminences and alveolar tubercules; a broad palate with uniform depth of vault in the maxillary arch.
  3. Broad buccal shelf and firm retromolar papillae in the mandibular arch.
  4. A definite vestibular fornix, devoid of muscle attachments.
  5. Frenum attachments high in the maxillary and low in the mandibular arches.
  6. A clearly defined and well-developed lingual sulcus.
  7. A lateral throat form that allows suitable extension into the retromylohyoid space.
  8. A firm mucosal covering over the denture-bearing area.
  9. Mucous membrane in the vestibule fornix and floor of the mouth which is loosely and movably attached for denture seal.
  10. A gradually sloping palate with a passive reflection at the junction of the hard and soft palate.
  11. A tongue normal in size, position, and function.
  12. A normally related maxilla to mandible.
  13. Good muscle tonus and coordination in mandibular movements.
  14. Adequate inter-ridge space for the favourable placement of teeth
  15. Saliva of suitable viscosity and quantity
  16. Hard and soft tissues devoid of any signs of pathologic disorder.

Reference: Syllabus of Complete Denture By HEARTWELL – 4th edition

DAVIS CROWN

(WALLACE CLYDE DAVIS) 1866-1950

  • This is a dental restoration supported by a dowel in the root canal over which a porcelain tube teeth is placed directly on the root face of the tooth.
  • It is one type of dowel crown, which is detachable or called as the detached dowel type.
  • It is cemented in position uniting the tooth, dowel and crown into one unit.

1. When excessive tooth decay has occurred, there will be discrepancy between the fit of the crown and root planes. The cast base is attached to the dowel.

2. Porcelain is fused and interposed between the crown and root planes.

1. Preparation if labial and lingual planes is done

2. A complete porcelain crown of proper mould, size amd shape is selected.

3. The dowel is fitted in the root canal.

4. A platinum ferrule (0.0005 inch thick) is adapted on the dowel extension.

Porcelain crown is placed over the dowel and ferrule.

The crown position, with adjacent teeth and alignment is verified and the crown is fitted to the dowel with sticky wax and removed.

• A platinum foil 0.0001 inch is burnished onto the root face of die and the crown, ferrule and dowel is seated on platinum foil.

• The gap between the porcelain crown and swaged platinum matrix is sealed with melted inlay wax and is removed.

• This is invested and burn out done to remove the inlay wax. The temperature of furnace is raised to 1093°C and medium-fusing porcelain is placed at the area where wax has burned out.

• Depending on the morphology, porcelain can be added and fired to form the correct contours. Excess porcelain is ground and glazed to complete the restoration.

Reference : Exam Preparatory Manual By Lovely M on Fixed Partial Dentures

Topics Related To CHRONIC LIVER DISEASE

Between Portal and Systemic Veins. Sites are:

1. At the lower end of oesophagus – esophageal tributaries of left gastric vein ( portal) communicate with oesophageal tributaries of hemiazygous veins (systemic).

2. At the lower end of rectum and anal canal – superior rectal vein (portal) communicates with middle and inferior rectal veins (systemic).

3. Anterior abdominal (around umbilicus):

  • Paraumbilical vein (portal) communicates with systemic veins in epigastric, lateral thoracic, intercostal and lumbar veins.
  • Paraumbilical vein (portal) communicates with diaphragmatic veins (systemic) by a number of small veins, called accessory portal system of Sappey.

4. At bare area of liver – portal radicles of liver communicates with diaphragmatic veins (systemic)

5. At retroperitoneal site – the splenic and colic veins (portal) communicate with renal veins and other tributaries of IVC by small veins, called veins of Retzius.

6. At the fissure for ligamentum venosum, rarely, persistent ductus venosus establishes direct portocaval anastomosis (in fetal life, left branch of portal vein at the porta hepatitis communicates with IVC via ductus venosus. After birth, ductus venosus is fibrosed to form ligamentum venosum).

It consists of central arteriole from which numerous capillaries radiate, looks kike spider legs. Size varies from pinhead to 1-2 mm (sometimes cm). These are found along the area of SVC, commonly in neck, face, chest, and dorsum of hand and above nipple lines, cause of which is not known. It blanches on pressure, may pulsate if large. Better seen with glass slide or pinhead.

Causes of spider angioma:

1. Physiological:

  • Rarely present in normal people (2%), one to two in number, common in children. If >2 in number, it is usually pathological, especially in male than female.
  • Pregnancy (usually in the third trimester, disappears after 2 months of delivery)

2. Pathological:

  • CLD, commonly in alcoholic cirrhosis (disappears with improvement of liber function, appearance of new spider indicates deterioration of liver function).
  • Viral hepatitis ( transient).
  • Estrogen therapy and estrogen-containing oral contraceptive pill.
  • Rarely, in rheumatoid arthritis, thyrotoxicosis.

Mechanism of spider angioma:

  • Due to hyperdynamic circulation
  • Excess estrogen level (due to reduced metabolism by the liver).

Differential diagnosis of spider angioma:

  • Purpura (spontaneous bleeding into skin and mucous membrane, does not blanch on pressure and there is progressive color change)
  • Hereditary hemorrhagic telangiectasia
  • Campbell de Morgan Spots
  • Venous stars

These are 2-3 cm lesions that occur on dorsum of foot, leg, back and lower chest. Caused by elevated venous pressure amd are usually found overlying the main tributary of large veins. Do not blanch on pressure and blood flow if from periphery to the center of lesion (opposite to spider angioma).

Redness in thenar and hypothenar eminence and pulp of fingers. Blanches of pressure. With glass slide, flushes synchronously with pulse. Causes of palmar erythema:

1. Physiological:

  • Normal people, may be familial
  • Pregnancy

2. Pathological:

  • CLD (commonly alcoholic cirrhosis)
  • Thyrotoxicosis
  • Polycythemia
  • Prolonged rheumatoid arthritis
  • Chronic leukemia
  • Febrile illness.

Mechanism of palmar erythema:

  • Hyperdynamic circulation
  • Probably, high estrogen ( controversial)

Reference: Clinical Medicine – ABM Abdullah

MUSCLES OF VOCAL CORDS AND LARYNX

• Damage to external laryngeal nerve causes weakness of phonation due to loss of tightening effect of the cricothyroid on the vocal cord.

• The internal laryngeal nerve supplies the mucous membrane above the level of vocal folds whereas the recurrent laryngeal nerve supplies the mucous memberane below the level of vocal folds.

• In adult male, the larynx lies in front of 3rd,4th,5th and 6th cervical vertebrae, but in children and in adult female it lies at the higher level.

Source: Dental Pulse Multiple Choice Questions Textbook for NEET by Satheesh Kumar Reddy