ANSWER
2mm

OTHER OPTIONS
• Nil

SYNOPSIS
• The ferrule effect can be defined as a 360 metal collar of the crown surrounding the parallel walls of the dentine extending coronally to the shoulder of the preparation – Sorensen, and Engelman
• A minimum of 1.5 and an optimum of 2mm height of tooth structure should be available to allow for a ferrule effect.
• A ferrule can potentially improve the biomechanical stability of a tooth, by shifting the interfaces that resist stresses, from the weak tooth, core, and post interfaces, to a strong tooth, core, and post interface that is located at the ferrule margin.

REFERENCE
Grossmans Endodontic Practice

ANSWER
Occlusal

OTHER OPTIONS
• Periapical – These x-rays are often used to detect any unusual changes in the root and surrounding bone structures
• Bitewing – Bitewing X-rays detect decay between teeth and changes in the thickness of bone caused by gum disease. Bitewing X-rays can also help determine the proper fit of a crown or other restorations

SYNOPSIS
• Occlusal X-rays are designed to capture what goes on inside the roof or floor of the mouth, which helps the dentist see full tooth development and placement
• The main clinical indications include
– Periapical assessment of the upper anterior teeth, especially in children but also in adults unable to tolerate periapical holders
– Detecting the presence of unerupted canines, supernumeraries, and odontomes
– As the midline view, when using the parallax method for determining the Buccal or palatal position of unerupted canines
– Evaluation of the size and extent of lesions such as cysts or tumors in the anterior maxilla
– Assessment of fractures of the anterior teeth and alveolar bone.

REFERENCE
Occlusal Radiograph – Pocket Dentistry

ANSWER
All the above

OTHER OPTIONS
• Nil

SYNOPSIS
• The materials such as glass ionomer cements, Resin modified glass ionomers, compomers and composites are able to release fluoride ions in the oral environmental.
• The fluoride ions released combines with hydroxyapatite crystals in the inorganic portion of the tooth to form fluorapatite which is a caries-resistant complex.
• The rate and pattern of release of fluoride ions from restorative materials depends on various factors such as
– Temperature,
– pH of the environment,
– Mixing technique,
– Powder liquid ratio,
– Media surrounding the material,
– Area that is exposed to the oral environment, etc.

REFERENCE
Estimation of Fluoride Release from Various Dental Materials in Different Media—An In Vitro Study

ANSWER
RCT is the treatment of choice

OTHER OPTIONS
• DPC- Indicated for permanent tooth with a normal pulp following a pinpoint exposure of less than 1mm during cavity preparation or traumatic injury
• Pulpotomy – A pulpotomy is performed in primary as well as permanent tooth when caries removal results in a pulp exposure greater than 1mm in a tooth with normal pulp or reversible pulpitis or after traumatic pulp exposure and there is no radiographic sign of infection or pathologic resorption.
• Apexification- Its a procedure of inducing root end closure of an incompletely formed non vital permanent tooth by removing the coronal and non vital radicular tissue just short of the root end and placing a biocompatible agent such as CaOH in the canals for 2 weeks to 1month to disinfect the canal space and root end closure is accomplished with an apical barrier such as MTA

SYNOPSIS
• RCT is the treatment of choice for a fully matured tooth ( root formation of 21 is completed by age of 10) due to traumatic pulp exposure that exceeded 24hrs or shows signs of necrosis
or irreversible pulpitis
• RCT is indicated for a restorable permanent tooth with a closed apex that exhibits exposure or signs of irreversible pulpitis or a necrotic pulp to eliminate pulpal and periradicular infection
• Following cleaning,disinfection and shaping of the canal ,obturation of entire root canal is accomplished with a proper obturating material

REFERENCE
Pulp therapy for Primary and Immature Permanent teeth- Latest Revision -2020 ,THE REFERENCE MANUAL OF PEDIATRIC DENTISTRY

ANSWER
Lateral pterygoid

OTHER OPTIONS
• Masseter – The large muscle which raises the lower jaw, and assists in mastication.
• Temporalis – A broad muscle that fans out to cover much of the temporal bone on the side of the skull that elevates and retracts the jaw.
• Medial pterygoid – The medial pterygoid elevates and closes the jaw, contributes to protrusion of the mandible, and assists in mastication.

SYNOPSIS
• Lateral pterygoid is a muscle of mastication with two heads. It lies superiorly to the medial pterygoid.
• The lateral pterygoid is the only muscle of mastication that actively opens the jaw.
• Unilateral action of a lateral pterygoid produces lateral movement in the jaw, usually performed in concert with the medial pterygoids

REFERENCE
Muscles of mastication – Pocket Dentistry

ANSWER
Moderate

OTHER OPTIONS
• Explained below

SYNOPSIS
• According to WHO Global Data Bank
• DMFT – 0 – 1.1 – Very Low Risk
• DMFT – 1.1-2.6 – Low Risk
• DMFT – 2.7- 4.4 – Moderate Risk
• DMFT – 4.5 -6.5 – High Risk
• DMFT – 6.6 and above – Very High Risk

REFERENCE
A Textbook of Public Health Dentistry – CM Marya

ANSWER
Crane Pick Elevator

OTHER OPTIONS
• Tissue Forceps – Non-toothed forceps used for fine handling of tissue and traction during dissection
• Crile hemostat- Crile hemostatic forceps are atraumatic and non-toothed clamps used to clamp blood vessels, grab tissue or vessels
• Allis Forceps -The Allis clamp is a surgical instrument with sharp teeth, used to hold or grasp heavy tissue. It is also used to grasp fascia and soft tissues such as breast or bowel tissue

SYNOPSIS
• Crane Pick Elevator is used to elevate broken roots from the socket.
• The 45 degrees angled sharp tip penetrates the root and does not put pressure on nearby teeth.
• As a result, it not only loses the tooth from the gums smoothly, but it also prevents trauma to the surrounding area of the impacted tooth

REFERENCE
Oral Surgery Extraction Instruments – Pocket Dentistry

ANSWER
Apposition

OTHER OPTIONS
• Initiation – Anodontia, hypodontia etc
• Histodifferentiation – Cysts or neoplasm
• Morphodifferentiation – Anomalies in morphology of teeth

SYNOPSIS
• Systemic postnatal infection (e.g. measles, chicken pox, streptococcal infections, scarlet fever) can cause enamel hypoplasia.
• The band-like discoloration on the tooth is visualized where the enamel layer has a variable thickness and becomes extrinsically stained after tooth eruption.
• Enamel hypoplasia occurs when the special cells that produce dental enamel are disturbed during a particular stage of enamel formation – the matrix formation stage or apposition stage

REFERENCE
Shafer’s Textbook of Oral Pathology

ANSWER
Hyperventilation

OTHER OPTIONS
• Angina – Classically, the pain of angina is described as a crushing or band-like tightness of the chest which may radiate to the left arm or mandible.
• Asthmatic attack – The signs and symptoms of asthma include- Breathlessness (rapid respiration − more than 25 breaths per minute), expiratory wheezing, use of accessory muscles of respiration, and tachycardia.

SYNOPSIS
• Chest pain does not necessarily indicate cardiac disease.
• The most common causes of acute chest pain encountered in dental situations include hyperventilation, pulmonary embolism, angina pectoris, and myocardial infarction.
• Stress and fear often cause rapid breathing or hyperventilation.
• Hyperventilation(panic attack) is a more common emergency than is often thought.
• Anxiety is the principal precipitating factor. The signs and symptoms of hyperventilation include
– Anxiety
– Light-headedness
– Dizziness
– Weakness
– Paraesthesia
Tetany- Hyperventilation leads to carbon dioxide being ‘washed out’ of the body, producing an alkalosis that causes muscle spasms.
– Chest pain and or palpitations
– Breathlessness.
• Treatment for hyperventilation involves the following
– A calm and sympathetic approach from the practitioner as the diagnosis, particularly in the early stages, is not always as obvious as it may seem
– Exclusion of other causes for the symptoms
– Encourage the patient to rebreathe their own exhaled air to increase the amount of inhaled carbon dioxide − a paper bag placed over the nose and mouth allows this. If no paper bag is handy, the patient’s cupped hands would be alternative.

REFERENCE
Medical Emergencies in Dental Practice Management of Specific Medical Emergencies – GDC

ANSWER
Fibrous dysplasia

OTHER OPTIONS
• Paget’s disease – Pagets disease of bone occurs most frequently in the pelvic and leg bones, skull, and lower spine. It is most common in older individuals and may lead to bone pain, deformities, and fractures.
• Osteosarcoma – Osteosarcoma is a type of bone cancer that begins in the cells that form bones. Osteosarcoma is most often found in the long bones — more often the legs, but sometimes the arms — but it can start in any bone.
• Osteopetrosis – Osteopetrosis is a rare disorder that causes bones to grow abnormally and become overly dense. When bones become overly dense, they are brittle and can fracture (break) easily. In addition, bones may be misshapen and large, causing other problems in the body.

SYNOPSIS
• Fibrous dysplasia usually occurs in children ages 3 to 15, but it sometimes is not diagnosed until adulthood.
• The exact cause of fibrous dysplasia is not known, but it is not passed down through families.
• Symptoms may include
– Bone pain and deformity,
– A waddling walk, and scoliosis.
• The spectrum of bone lesions can be classified into three primary bony patterns – cystic, sclerotic, and mixed.
• Histological appears as
– Irregularly shaped trabeculae of immature, woven bone in a background of variably cellular, loosely arranged fibrous stroma.
• Radiographically, appears as
– A well-circumscribed lucent lesion in the metaphysis or diaphysis with a ground-glass appearance.
– The cortical bone may be thinned with diffuse endosteal scalloping.
– Periosteal reaction is usually not seen unless a pathologic fracture appears
• Treatment may include surgery, medicines, pain management, or physical therapy.

REFERENCE
Shafer’s Textbook of Oral Pathology

ANSWER
Antipsychotics

OTHER OPTIONS
• Beta blockers and Calcium channel blockers are antihypertensives that reduces salivary secretion

SYNOPSIS
• Excessive salivation is a paradoxical adverse effect of antipsychotic treatment possibly due to the antimuscarinic properties of several antipsychotics.
• The proposed mechanism of sialorrhoea is by the blockade of alpha-2 adrenergic receptors or decreased noradrenaline and direct agonism of M3 and M4 muscarinic receptors.
• Sialorrhoea occurs in 30 – 80 percent of patients with schizophrenia receiving clozapine
• Antipsychotic medications such as clozapine and olanzapine may induce excessive (hyper) salivation, which can be uncomfortable and embarrassing as well as increasing the risk of aspiration pneumonia

REFERENCE
Essentials of Pharmacology for Dentistry – K D Tripathi

ANSWER
Clean with soap and water, Assess the patient’s risks

OTHER OPTIONS
• Not applicable

SYNOPSIS
• Needlestick injuries are associated with a number of blood-borne infections and are common among dental health professionals.
• Percutaneous exposure incidents facilitate the transmission of bloodborne pathogens such as human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B virus (HBV).
• The UK Health And Safety Executive has a guideline to deal with needle stick injuries
– If you suffer an injury from a sharp which may be contaminated
1. Encourage the wound to gently bleed, ideally holding it under running water
2. Wash the wound using running water and plenty of soap
3. Don’t scrub the wound while you are washing it
4. Dry the wound and cover it with a waterproof plaster or dressing
6. Seek urgent medical advice (for example from your occupational health service) as effective prophylaxis (medicines to help fight infection) are available
7. Report the injury
8 Assess the patient’s Risk

REFERENCE
Best Practices in Phlebotomy -WHO Guidelines on Drawing Blood
Guidelines to deal with needle stick injuries -The UK Health And Safety Executive

ANSWER
Convex profile, long face

OTHER OPTIONS
• Not applicable

SYNOPSIS
• Children who breathe through the mouth are more likely to develop facial structures that are
– Long,
– Narrow,
– Have less prominent jaws, and
– A retracted chin.
– They have significant lower incisor proclination,
– Lip incompetency and
– Convex facial profile.

REFERENCE
Contemporary Orthodontics – William R Profitt

ANSWER
Erosion

OTHER OPTIONS
• Abrasion- It refers to the loss of tooth substance induced by mechanical wear other than that of mastication. Abrasion results in saucer-shaped or wedge-shaped indentations with a smooth, shiny surface.
• Attrition- It is defined as a physiological, continuous, process resulting in loss of tooth structure from direct frictional forces between contacting teeth.
• Abfraction- Abfractions are the microfractures which appear in the enamel and possibly the dentine caused by flexion of the cervical area of the tooth under heavy loads. These lesions usually appear as wedge-shaped defects with sharp line angles.

SYNOPSIS
• Erosion- It can be defined as a loss of tooth substance by a chemical process that does not involve known bacterial action. The eroded area appears smooth, hard and polished
• It is one of the noncarious defects of teeth.
• It is associated with diseases such as GERD, and also can effect from the acidic content of routine food stuffs.

REFERENCE
Textbook of operative dentistry –Nisha Garg -3rd Edition

ANSWER
Apexogenesis

OTHER OPTIONS
• Apexification – For non-vital tooth
• Direct pulp capping – For incipient pulp exposure
• RCT – In closed apex cases

SYNOPSIS
• Apexogenesis refers to a vital pulp therapy procedure performed to encourage physiological development and formation of the root end in young permanent tooth in cases of large traumatic exposure of pulp.
• It is a procedure where vital tissue within the tooth is maintained to facilitate the continued development of the immature root.
• A portion of the inflamed pulp is removed and filled with a bioceramic material that maintains vitality in the roots. Healthy tissue then allows for continued root development.
• Vital pulp capping with MTA in apexogenesis has superior long-term sealing ability and stimulates the formation of a higher quality and greater amount of reparative dentin. 
• The calcified bridge formed by MTA is continuous and has no evidence of tunnel defects.

REFERENCE
Apexogenesis and apexification with mineral trioxide aggregate (MTA) -a report of two cases -Endodontic Practice

ANSWER
462 mg

OTHER OPTIONS
• Not applicable

SYNOPSIS
• Dental carpules are small cylindrical glass tubes containing dental anesthetics which are screwed onto dental syringes and are commonly aspirated while the practitioner injects the patient.
• MRD (Maximum Recommended Dose) without epinephrine is 4.4mg per kg, and MRD with epinephrine is 7.7mg per kg
• MTD (Maximum Total Dose) = MRD(Maximum Recommended Dose) x weight of the patient.
• Putting the values into the formula, MaximumTotal Dose = 7.7 x 60= 462 mg
-Without epinephrine, the values change accordingly

REFERENCE
Malamed SF- Handbook of Local Anesthesia

ANSWER
Tapered Fissure Bur

OTHER OPTIONS
• Cylindrical bur – used for the removal of amalgam restorations
• Diamond bur Diamond Burs are used to grind away tooth tissue and cut through porcelain, and are mostly used with high-speed handpieces to leave a rough finish.
• Round bur excavate tissue for cavity preparation. opening the tooth for endodontic treatment, general cleaning of the tooth structure from caries, and selective grinding. Round burs are also used for bone surgery.         

SYNOPSIS
• Tapered fissure burs are especially designed to make the task of crown and bridge preparation simpler and more efficient.
• There are 2 types Flat end tapered and round end tapered
• Flat-end tapered fissure bur is used to obtain the shoulder finishing line in tooth preparations for receivig crown

REFERENCE
Fundamentals of Tooth Preparations – Schillingburg Jacob Brackett

ANSWER
Cortical decalcified freeze dried bone graft

OTHER OPTIONS
• Explained below

SYNOPSIS
• If the defect is lined by only two walls of bone, the defect is a two-wall defect.
• Cortical decalcified freeze-dried bone allograft is used for 2 walled osseous defects
• Cortical bone contains pure cortex-dense bone, hence it is used for weight or force-bearing areas
• Freeze drying decreases antigenicity and facilitates long-term storage
• Decalcifying improves osteostimulatory properties
• Cancellous bone provides more open spaces for faster revascularisation, but it lacks mechanical strength, particularly used for non-weight or non-force-bearing areas

REFERENCE
Carranza’s Clinical Periodontology

ANSWER
Irreversible pulpitis

OTHER OPTIONS
• Reversible Pulpitis – Non lingering pain that subsides on removal of stimuli
• Pulp necrosis – No response to vitality test
• Dentinal hypersensitivity – Short intense pain while having hot or cold food stuffs

SYNOPSIS
• Irreversible pulpitis is when the inflammation has completely damaged the pulp, which can’t be saved. 
• Symptoms of irreversible pulpitis include
– Nocturnal pain
– Spontaneous pain
– Sensitivity to cold that lasts more than 30 seconds
– Sensitivity to heat
– Pain when the tooth is tapped
– Swelling around tooth and gums
– Fever
– Pain on lying down
– Pain that is radiating
– Trouble finding which tooth is causing the pain‌
• As inflammation builds in the tooth, the pulp can die. This can happen with irreversible pulpitis and, once this occurs, the pain will stop.

REFERENCE
Dental Pulp Testing, A Review.- International Journal of Dentistry. 2009

ANSWER
0.25N

OTHER OPTIONS
• Not applicable

SYNOPSIS
• The probing around implants represents a good technique for assessing the status of peri-implant mucosal health or disease.
• Probing disrupts the epithelial attachment to implant surfaces but does not cause permanent damage to theperi-implantt soft tissue seal.
• The extent of probe penetration is influenced by the probing force, ideally 0.25 Newtons.
• Therefore, automated controlled-force probes offer better reproducibility of probing depth.
• Other factors that influence probing depth are angulation, probe tip diameter, implant surface characteristics, presence of cement remnants, and degree of soft tissue inflammation

REFERENCE
Contemporary Implant Dentistry- Carl E. Misch- 3rd Edition

ANSWER
An increase in diameter by 0.02mm every 1mm of file

OTHER OPTIONS
• Not applicable

SYNOPSIS
• ISO normed hand files have a standardised taper of 2percent that equates to 0.02mm increase in diameter per mm of file.
• This standardised taper allows you to calculate the diameter of any given stainless steel file at any given point.
• Where the 2 percent taper means that there is an increase in diameter by 0.02mm every 1mm of file (moved in a coronal direction).
• The most apical point of any file is deemed D0, so moving coronal on the file by 1mm brings you to D1 and so on, up to D16 as there is a 16mm cutting surface on all files.

REFERENCE
Endodontic files and Reamers-Textbook of Endodontics -Nisha Garg

ANSWER
Prions

OTHER OPTIONS
• Viroids – Viroids are infectious agents that consist only of naked RNA without any protective layer such as a protein coat. 
• Orthomyxovirus – The genome of orthomyxoviruses consists of multiple segments of negative-sense, single-stranded RNA molecules, each packaged in the form of rod-shaped, double-helical ribonucleoprotein (RNP) complexes.
• Spores – A spore is a cell that certain fungi, plants (moss, ferns), and bacteria produce. They can resist high temperatures, humidity, and other environmental conditions.

SYNOPSIS
• Prions form abnormal aggregates of proteins called amyloids, which accumulate in infected tissue and are associated with tissue damage and cell death
• Unlike other infectious agents, such as bacteria, viruses, and fungi, prions do not contain genetic materials such as DNA or RNA.
• The unique traits and genetic information of prions are believed to be encoded within the conformational structure and posttranslational modifications of the proteins.
• Prions, like all proteins, are composed of long chains of amino acids linked together
• Identified Prion Diseases are
– Creutzfeldt-Jakob Disease (CJD)
– Variant Creutzfeldt-Jakob Disease (vCJD)
– Gerstmann-Straussler-Scheinker Syndrome.
– Fatal Familial Insomnia etc

REFERENCE
Prion Diseases – Centre for Disease Control and Prevention

ANSWER
Autonomy

OTHER OPTIONS
• Beneficiance – The principle of beneficence is a moral obligation to act for the benefit of others. There are 2 aspects of beneficence
– Providing benefits
– Balancing benefits and risks or harm
• Justice – It means giving each person what he or she deserves or, in more traditional terms, giving each person his or her share
• Non-maleficiance – The principle of nonmaleficence holds that there is an obligation not to inflict harm on others

SYNOPSIS
• Autonomy is the innate human right of a patient to control access to his or her body and what is done to him or her.
• It involves the right to choose who treats him or her, where he or she is treated, and what treatment is used.
• It also involves the authorization of the treatment.
• It is not enough for the patient to consent to a course of treatment- he must actually authorize the physician to go ahead with the chosen treatment.

REFERENCE
Professionalism and Ethics Handbook for Residents (PEHR)- A Practical Guide.
Saudi Commission for Health Specialties, Riyadh – 2015

ANSWER
Half the normal dose

OTHER OPTIONS
• Not applicable

SYNOPSIS
• The patients who are taking tricyclic antidepressants or monoamine oxidase inhibitors should receive only 50 percent of the usual dose of adrenaline because of an interaction that is potentially dangerous.
• Half doses of adrenaline (epinephrine) may also be safer for patients on beta blockers

REFERENCE
Resuscitation Council (UK). The Emergency Medical Treatment of Anaphylactic Reactions for First Medical Responders and for Community Nurses Revised January 2002, May 2005.

ANSWER
Apron, Mask, Eye protection, Gloves

OTHER OPTIONS
• Not applicable

SYNOPSIS
• The order for putting on PPE is
1) Apron or Gown,
2) Surgical Mask,
3) Eye Protection (where required), and
4) Gloves

REFERENCE
Infection Control – CDC