Tag: Dental students

CANINE RETRACTORS

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Canine retractors are springs that are used to move canine in a distal direction.

🔹ETIOLOGY:

  • slightly abnormal path of eruption
  • Local tooth displacements as in class 1 malocclusion
  • Buccal displacement is more common in crowded arch
  • Palatal displacement is more common in uncrowded arch & is associated with small or abnormal root formation of 2’s.

🔹CLASSIFICATION:

1. Based on location

  • Buccal (Buccally placed)
  • Palatal (Palatally placed)

2. Based on presence of helix or loop

  • Canine retractors with helix
  • Canine retractors with loop

3. Based on mode of action

  • Pull type
  • Push type

▪️BUCCAL CANINE RETRACTOR:

INDICATION: Is used where a buccally placed canine has to be moved palatally as well as distally.

TYPES:

• Self supporting or unsupported

• Supported

▪️SELF SUPPORTED BUCCAL CANINE RETRACTOR:

DESIGN & CONSTRUCTION

  • 0.7mm wire used
  • Coil lies just distal to the long axis of the tooth
  • Mesial arm-active arm, should be away from the tissue surface & should run parallel to the long axis of the canine
  • At about the middle third of canine a right angled bend is given to the active arm & is adapted on the mesial side of the canine.
  • Distal arm-retentive arm, adapted to the mesial aspect of 2 PM

ACTIVATION

👉🏻The spring should be activated by only 1mm. Only spring which is activated by closing the coil

👉🏻Distal activation- It is effected at the coil by bending the anterior limb over the round beak of a pair of spring forming pliers

👉🏻Palatal activation- It is undertaken in the anterior limb after it emerges from the coil

DISADVANTAGES

  • More flexible vertically than it is mesiodistally
  • Often stiff
  • Not indicated in lower arch

▪️SUPPORTED BUCCAL CANINE RETRACTOR:

DESIGN

  • Identical in design to unsupported but made from 0.5mm wire supported in tubing
  • More than twice as flexible as the standard retractor
  • Tubing imparts excellent vertical stability

ACTIVATION

  • Activation by 2mm
  • Adjustment made as described for self supporting BCR
  • More important not to bend the wire where it emerges from the tubing otherwise it may # at this site of stress concentration

▪️AN APPLIANCE TO RETRACT BUCCAL CANINE

Indication

  • Class 1 –crowding, upper canines are usually buccally placed
  • Class 2- to retract canine to provide space for overjet reduction
  • Active component
  • Supported buccal canine retractor
  • 0.5mm Sheathed in tubing.
  • Retention
  • adams clasp on 6|6.
  • Southend clasp on 1|1.
  • Baseplate
  • Normal full coverage
  • Anchorage
  • Spring pressure must be kept light

▪️SOLDERED AUXILIARY SPRINGS TO MOVE A CANINE PALATALLY

• It is possible to solder a spring{0.7mm wire} to the bridge of the adams clasp on a first molar.

• The spring can be used to tuck an outstanding canine

Advantages

  • Spring does not cross embrasure & does not compete with other wirework
  • Added easily to an existing appliance

Disadvantages

  • When the clasp is adjusted the spring position is also affected.
  • Difficult to add a spring to a clasp that is already carrying a soldered tube for facebow

▪️REVERSE LOOP BUCCAL RETRACTOR:

INDICATION

  • When the canine is placed in the line of the arch & has to be just distalized
  • Favored in shallow sulcus as in lower arch

DESIGN

  • 0.5mm ss wire used
  • The coil is placed as high as possible in the sulcus, but short of the final depth in relation to the space to which the canine has to be moved
  • Mesial arm-retentive arm, lies mesial to 2 PM
  • Distal arm-active arm. place at right angled bend to the active arm at about the cervical margin of the teeth & adapt it on the mesial side of the canine

ACTIVATION

  • Should be activated by not more than 1mm
  • Cut off 1mm of wire from the free end & re-forming it to engage the mesial surface of the tooth
  • Alternatively it can be activated by opening the loop by 1mm, it is better not to adjust at the loop in lower arch because this moves the active end of the spring occlusally so that secondary adjustment is required

DRAWBACKS

• It is stiff in the horizontal plane yet very unstable vertically

▪️An appliance to retract lower canine

Indication

Anterior crowding

Active component

Reverse loop buccal retractor

Retention

Adams clasp on 6|6

Baseplate

A lingual bar rather than acrylic in the incisor region

Anchorage

Clasped teeth

Teeth and alveolar process contacted by the appliance

▪️U loop canine retractor

INDICATIONS

  • Distal movement of canines
  • Where functional depth of sulcus is less

DESIGN

  • 0.7mm ss wire used
  • A U-loop approximately equal to the width of premolar is made
  • Mesial arm-active arm. At about the cervical margin of canine,a right angled bend is placed on the active arm to engage the mesial side of the canine
  • Distal arm-retentive arm, is adapted mesial to the 2 PM

ACTIVATION – Close the loops by 1mm or free end is cut by 1mm & it is readapted on to the mesial side

DRAWBACKS – Requires frequent adjustments

▪️AN APPLIANCE TO MOVE A CANINE OCCLUSALLY

Indication – Partially erupted canine

Active component – U loop canine retractor, engages a hook bonded to the buccal surface of the canine

Retention – Adams clasp on 6|6

Baseplate – As much palatal coverage as the canine position permits to offer max. resistance to the occlusally directed force

Anchorage – Acrylic in the palate

▪️Buccal acrylic appliance to retract lower canine

Indication – To overcome the dual problems of limited space for tongue & poor retention provided by adams clasp

Active component – Buccal canine spring 0.7mm

Retention – Lingually placed jacksons clasp on the first molar [to overcome the problem of limited undercut on the buccal aspect of lower molars, appliances have been described with clasping on the lingual aspect of molars BELL 1983]

Baseplate – 2 segments of acrylic 1-2mm from the buccal mucosa. These are connected in the midline by a heavy ss bar, {2mm x 1mm}oval in cross section lying close to buccal mucosa below the lower incisors

Anchorage – First molar, with minimal anchorage effect from acrylic

▪️PALATAL CANINE RETRACTOR:

INDICATIONS – In cases where canine is placed palatally & requires distal & buccal movement

DESIGN

  • 0.5mm ss wire used
  • coil is placed along the long axis of the canine
  • Distal arm-active arm, placed mesial to canine
  • Mesial arm-retentive arm, is bent at rt angle & extends up to mesial aspect of first molar where a retentive tag is placed

ACTIVATION – By opening the coil by 2-3mm where the active arm emerges out of the coil

▪️CONCLUSION:

• For canine retractors whether buccal or palatal to be successful, it is important for the canines to be mesially angulated prior to treatment

• If the canine is normal & distally angulated prior to treatment, a removable canine retractor will cause an unsightly distal angulation of the canine at the completion of retraction which in turn will take a long time to correct with fixed appliance

• For this reason, use of removable appliance for canine retraction is declining as fixed appliance have greater control over tooth movement

References:

  1. Textbook of Orthodontics The Art and Science 6th Edition By Bhalajhi; Internet
  2. Image Source: Google

BULLOUS PEMPHIGOID

Dr.Mehnaz1 Comment

A chronic, autoimmune, sub-epidermal blistering skin disease that rarely involves mucous membrane.

🔹Clinical Features:

Age: Elderly (>60 years)

Skin Lesions:

  • Generalised non-specific rash, commonly on Limbs.
  • Appears urticarial/eczematous; persist for several weeks to months.
  • Vesicles & bullae arise in prodromal skin lesion as well as Normal skin.
  • The blisters are thick walled and don’t rupture easily.
  • ruptured blisters are usually sensitive and painful, have raw eroded area which heals rapidly.

Oral Manifestations:

Vesicles appear gingivally👇🏻

Erythematous & desquamate as result of minor frictional trauma

👉🏻 Oral lesions comprise of bullae/vesicle that rupture to form erosions and ultimately leave out ulcerations

👉🏻 Other sites:

  • Buccal Mucosa
  • Tongue
  • Floor of the mouth
  • Palate

🔹Diagnosis:

Apart from evaluating history, clinical presentation, histopathological analysis is carried out followed by direct immunofluorescence study for the differential diagnosis and confirmation of the condition.

👉🏻Histopathology:

  • Acanthotic mucosa
  • Subepidermal non-specific vesicles with fibrous exudate

👉🏻Direct immunofluorescence is found to be the gold standard test. Deposition pattern of different types of immunoreactants differentiates the various immune-mediated diseases. Direct immunofluorescence shows presence of IgG and C3 deposits along the basement membrane zone.

©️jiaomr.in
👉🏻Electron Microscopy: In bullous pemphigoid (BP), the 180 kD antigen (BPAG2) was shown by immuno-EM to be a transmembrane molecule and to possess an autoantibody binding site outside the cell, suggesting a major pathogenic role for the BPAG2 in blister formation.

🔹Differential Diagnosis:

• Mucous membrane pemphigoid can be differentiated from BP by its predominant involvement of mucosal surfaces and positive Nikolsky’s sign.

• Lichen planus pemphigoides is clinically differentiated by the presence of lichen planus lesions in addition to tense blisters.

• Nikolsky’s sign is present in case of pemphigus and cicatricial pemphigoid, but not in the case of BP.

🔹 Treatment:

👉🏻Treatment is based on the degree of cutaneous and oral involvement. Mostly, topical steroid (clobetasol propionate) gives satisfactory result in case of smaller area of skin involvement, whereas larger area of skin involvement and recurrent cases are treated satisfactorily with systemic steroids and immunosuppressive agents.

👉🏻Recommended dosage for oral prednisolone is 0.3–1.25 mg/kg body weight/day, controls disease within 1–2 weeks, followed by which the dose is tapered. Dexamethasone (100 mg in 500 mL 5% dextrose i.v. over 2–3 h for three consecutive days) is the preferred steroid for pulse therapy, either administered alone or in combination with cyclophosphamide.

Other drugs for treating BP include new antibody modulators, rituximab 375mg/m2weekly over 4 weeks and omalizumab subcutaneously 300–375 mg for every 6 weeks.

👉🏻Higher doses of systemic corticosteroids seem to be associated with higher mortality rates, which led to the addition of corticosteroid-sparing agents to the treatment of BP. The most frequently used immunosuppressive agent is azathioprine (0.5–2.5 mg/kg body weight/day). Others being cyclophosphamide, methotrexate, cyclosporine A, combination tetracycline/minocycline along with nicotinamide, and more recently, mycophenolate mofetil, a DNA synthesis inhibitor, and methotrexate, a folate antagonist.

👉🏻IVIg – A dose of 1–2 g/kg for five consecutive day cycle of 0.4 g/kg/day, although a 3-day cycle may be used in cases that are nonresponsive to conventional therapy.

Dr. Mehnaz Memon🖊

References:

  1. http://www.jiaomr.in/article.asp?issn=0972-1363;year=2018;volume=30;issue=4;spage=432;epage=435;aulast=Aparna
  2. https://www.cidjournal.com/article/S0738-081X(00)00178-4/abstract
  3. Shafer’s Textbook of Oral Pathology, 7th edition
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APERT SYNDROME

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🔖 Acrocephalosyndactyly. The condition is autosomal dominant i.e, one copy (out of 2) of the defective gene is sufficient to cause the abnormality in the offspring.

🔹Characteristics:

  • Craniosynostosis (premature fusion of the skull bones)
  • Craniofacial anomalies
  • Syndactyly (Fusion of fingers and toes)

🔹Etiology:

🔹What are the Symptoms and Signs of Apert Syndrome?

The various clinical features include:

  1. Asians affected
  2. Acrocephaly, Brachycephaly, flat occiput & prominent forehead.
  3. Late closing fontanels
  4. Low set ears, hearing loss
  5. Eyes: Down slanting of palpebral fissures, Widely spaced eyes(Hypertelorism), Shallow orbits, Abnormally bulging eyes (Exophthalmos)
  6. Nose: Depressed Nasal bridge, short, wide with bulbous tip, Parrot beaked appearance, Atresia
  7. Jaw:
  • Prominent Mandible
  • Maxillary hypoplasia
  • Drooping angles of mouth
  • High arched palate
  • Bifid uvula
  • Cleft palate
  • Crowded upper teeth
  • Malocclusion
  • Delayed & ectopic eruption
  • Shovel shaped incisors
  • Supernumerary teeth
  • V-shaped maxillary dental arch
  • Bulging alveolar ridges

8. Partial to complete fusion of digits: 2-4th digits – MITTEN HANDS & SOCK FEET; Sole – supinated

9. Intelligence – Normal

10. ⬆️ intracranial pressure – optic atrophy, papilledema

11. Hyperhidrosis

12. Cardiovascular system: Atrial Septal defect, Ventricular septal defect, Patent ductus Arteriosus

🔹How do you Treat Apert Syndrome?

Standard Therapies

The treatment of Apert syndrome aims at addressing the specific symptoms that may be present in the particular individual. Treatment is usually symptomatic and supportive.

  • Craniosynostosis and associated hydrocephalus in some cases may give rise to an abnormally increased pressure within the skull (intracranial pressure) and on the brain. In these cases, early surgery (within 2 to 4 months after birth) becomes necessary to correct the defects in the skull and facial bones.
  • Insertion of a tube (shunt) to drain excess cerebrospinal fluid (CSF) away from the brain and into another part of the body like the abdomen where the CSF can be absorbed can be done to relieve associated hydrocephalus (fluid accumulation in the brain).
  • Early repair and reconstructive surgery may also be done in some infants with Apert syndrome to address craniofacial abnormalities.
  • Other defects such as those of heart, eye and ear defects may also need correction.

Dr. Mehnaz Memon🖊

References:

  1. https://www.medindia.net/amp/patientinfo/apert-syndrome.htm
  2. Shafer’s textbook of Oral Pathology – 7th Ed.

PAGET’S DISEASE

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Introduction & Etiology👆🏻
Clinical Features & Phases of PDB..👆🏻
Clinical Features contd…👆🏻
O/M of PDB..👆🏻
Radiographic Features of PDB..👆🏻
Histological Features of PDB…👆🏻
Lab. Findings & Treatment of PDB..👆🏻

References: Shafer’s Textbook of Oral Pathology 7th Edition

Dr. Mehnaz Memon🖊

BURKITT’S LYMPHOMA

Dr.Mehnaz2 Comments

🌏 African Jaw Lymphoma

🌏 The endemic form is linked to malaria and to the Epstein-Barr virus (EBV), a common virus that also causes glandular fever.

🌏 A tumour peculiar to children of central Africa was reported by Denis Burkitt in 1950. It is a lymphoreticular cell malignancy.

▪️It is a high grade B-cell neoplasm & has 2 major forms:

🔷 Clinical Features:

1. Age – between 6 & 9 years

2. Sex – M:F – 2:1

3. Site: In African form (Endemic),

  • Maxilla > Mandible
  • Spreads to floor of orbit
  • Molar area
  • More than one quadrant is involved

American form (Non-endemic) – Oral: only 1 quadrant involved. Other: Mainly involves Abdomen.

4. Onset & progress – fast growth with tumor doubling time of <24 hours.

5. Symptoms –

  • Swelling of jaws, abdomen & paraplegia
  • Loosening of teeth
  • Abdominal tumors
  • Bowel obstruction

6. Sign – Lymphadenopathy (Non-tender)

🔷 Oral Manifestations:

  • Gingiva and mucosa – swollen, ulcerated, necrotic
  • Facial asymmetry
  • Teeth are pushed out of their sockets

🔷 Radiographic Features:

Moth-eaten appearance with loss of lamina dura around the teeth.

🔷 Histological Features:

1. Monoclonal proliferation of B-lymphocytes characterized by small non-cleaved cells.

2. Burkitt cells are homogenous in size & shape with –

  • round to oval nuclei
  • coarse chromatin
  • Multiple nucleoli
  • Basophilic vacuolated cytoplasm with neutral fat
3. Starry sky appearance – scattered macrophages with abundant clear cytoplasm, often containing phagocytic cellular debris👇🏻

🔷 Differential Diagnosis:

  • Non-hodgkins lymphoma
  • Cherubism
  • Osteosarcoma

🔷 Treatment: Intrathecal Chemotherapy

References: Shafer’sTextbook Of Oral Pathology

Dr. Mehnaz Memon🖊

Ann Arbor Staging System for Lymphoma: https://dentowesome.wordpress.com/2020/06/15/ann-arbor-staging/