Excel Dentistry 1st Year Past Papers PDF (2021)

EXCEL BDS EXCEL DENTISTRY Excel Dentistry A complete question bank for 1st year BDS students Editor Dr Syed Ahmed Khadri...

EXCEL BDS EXCEL DENTISTRY Excel Dentistry A complete question bank for 1st year BDS students Editor Dr Syed Ahmed Khadri BDS (MDS) Post Graduate Department of Oral and Maxillofacial Pathology Al-Badar Dental College and Hospital kalaburagi, Karnataka, India Editor in chief Dr Junaid Ur Rahman Syed BDS HKDET’s Dental College and Hospital Humnabad Dist Bidar. Karnataka Excel Dentistry 1 EXCEL BDS EXCEL DENTISTRY Headquarters Excel BDS 16-9-422/3, Ameen Enclave, Almond Street Old Malakpet Hyderabad 500 036 Phone: +91-74167-66894 Phone: +91-7829321670 Email: [email protected] Website: www.excelbds.com Inquiries for bulk sales may be solicited at: [email protected] First edition:2019 Second edition: 2020 Third edition: 2021 Price: 550/- 2 Excel Dentistry EXCEL BDS EXCEL DENTISTRY Dedicated to Our Parents Head of the Department Co - PGs Aspiring Students Excel Dentistry 3 EXCEL BDS EXCEL DENTISTRY Contributors Dr Nandini BDS (MDS) Dr Mohammed Zakir Mohiuddin owais Department of Public health Dentistry MBBS MS Mch Government Dental College and Hospital Assistant professor Chennai, Tamil Nadu, India (Paediatric Surgeon) Institute of child health Dr Meghashyama Kulkarni BDS (MDS) Niloufer hospital for women and child Department of Oral pathology Government Dental College and Hospital Bangalore, Karnataka, India Dr Abdul Rahim Rehan MBBS (MD) Department of Biochemistry Osmania College of Medical Sciences and Hospital Hyderabad, Telangana, India Dr Syed Nazeer Ahmed MBBS MD Associate professor Department of Anatomy Faculty of Medicine KBN University Kalaburagi, Karnataka, India Dr Ayub MBBS (MD) Department of General Medicine Basaveshwara College of Medical Sciences and Hospital Kalaburagi, Karnataka, India Dr Malik Aqueel BDS (MDS) Department of Oral and Maxillofacial and Pathology Al-Badar Dental College and Hospital Kalaburagi, Karnataka, India 4 Excel Dentistry EXCEL BDS EXCEL DENTISTRY Inspire yourself to aspire high Carve yourself to crave high Excel Dentistry 5 EXCEL BDS EXCEL DENTISTRY PREFACE The THIRD EDITION OF EXCEL DENTISTRY has been updated with recent advancements, hope the readers will find the book more informative and updated. The material in the book is introductory for a beginner in dentistry. Although there are many books, in this book we have solved 85 plus question papers from the previous 11 years question papers, and every topic was discussed in detail keeping in mind the information required. While updating the second edition of Excel dentistry, suggestions and corrections which were received from the students and colleagues have been taken into deeply grateful consideration. We are intensely grateful for all those who were involved with this. We are immensely thankful to so many colleagues as well as to the readers of the previous edition. Hopefully, the book provokes both positive and negative reactions. Despite many efforts, we accept imperfection in this book if any. As the Third edition of Excel dentistry, We genuinely welcome all the readers for any kind of suggestions or any mistakes and We’ll look forward to further improvement which will be deeply cherished. Finally, we extend my heartfelt thanks and acknowledge the pleasure of working with the EXCEL BDS TEAM. Dr Syed Ahmed Khadri Dr Junaid ur Rahman Syed 6 Excel Dentistry EXCEL BDS EXCEL DENTISTRY ACKNOWLEDGEMENTS Under Almighty’s guidance and blessings, it’s a matter of pleasure to introduce 3rd Edition of “ExcelDentistry” We are deeply grateful to my faculty and would like to owe a special note of thanks for all that today. First and fore most, we would like to thank Dr.Ayub, Dr.Malik Aqueel, Dr.Nandini and Dr. Meghashyama Kulkarni for their prop up. We are so thankful to our parents, siblings and well-wishers whose co-operation,encouragement and support which helped us during the complete preparation of this book. Dr. Ayub deserves special thanks for his continuous support and without any compromise to bring this book. We are thankful to the staff of EXCEL BDS, for their patience and continuous support. Last but not least, we’d like to thank our parents. Lastly, we acknowledge each and every person who helped us in some or the other way has inspired us and work hard towards making the quality of this book. Excel Dentistry 7 EXCEL BDS ANATOMY S.NO Question Title Answer Page No. OSTEOLOGY SHORT ESSAYS 1 Structure passing through Foramen Magnum(JUNE2014) 24 SHORT ANSWERS 1 Structure attached to mastoid process.(MARCH2021) 129 2 Name the structures passing through Foramen Ovale.(NOV2020, 65 DEC2016, DEC 2015) 3 Bones forming the orbital cavity(NOV2020) 121 4 Name any four Muscles attached to Hyoid Bone(DEC2018) 109 5 Name the parts of temporal bone.(JULY2018) 95 6 Muscles attached to Styloid process(DEC2013) 35 7 Foramen magnum.(JUNE2010) 24 8 Ligaments of Mandible.(JUNE2010) 02 SCALP,TEMPLE AND FACE LONG ESSAYS 1 Describe the scalp under the following heads: 96 (a) layers (b) blood supply (c) nerve supply (d) applied aspects (DEC2019,DEC2018) 2 Describe the Scalp under the following headings. 96 (a) Extent. (b) Layers. (c) Nerve supply. (d) Blood supply. (e) Lymphatic Drainage.(JUNE2012) SHORT ESSAYS 1 Motor and sensory nerve supply of the face.(MARCH2021) 128 2 Dangerous layer of Scalp and its applied Anatomy.(NOV2020) 15 3 Buccinator attachments, nerve supply, actions.(DEC2019,DEC2018,DE 103 C2012,JUNE2012) 4 Blood supply and Nerve supply of Scalp.(AUG2017) 96 5 Facial Artery origin, branches and termination(DEC2016) 63 6 Orbicularis Ocul(JUNE2016,DEC2015) 52 Excel Dentistry i EXCEL BDS ANATOMY 7 Sensory and Motor Nerve supply of Scalp(JUNE2014,DEC2013,DEC2010) 96 8 Vessels of face.(DEC2012) 13 9 Course of facial artery and it’s branches in the face.(JUNE2011) 63 10 Applied anatomy of the scalp(JUNE2011) 96 11 Facial nerve in face.(DEC2010) 128 12 Layers of the scalp.(DEC2010) 96 SHORT ANSWERS 1 Mention the components of lacrimal apparatus(MARCH2021) 129 2 Name the branches of facial artery in face(MARCH2021) 63 3 Applied anatomy of scalp.(JULY2018) 96 4 Extra Cranial branches of Facial Nerve(DEC2017) 84 5 Frontal Nerve.(JULY2015) 42 6 Branches of facial artery of face.(JUNE2013) 63 7 Dangerous area of Scalp.(DEC2012) 96 8 Branches of facial artery in the neck.(JUNE2012) 63 9 Nerve supply of scalp.(JUNE2010) 96 SIDE OF THE NECK SHORT ESSAYS 1 Carotid sheath formation, contents, relations.(DEC2019) 72 2 External Jugular Vein: formation, course, termination and tributaries. 105 (DEC2018,DEC2011) 3 Origin, course and branches of Lingual artery(JULY2018) 103 4 Name the layers of Deep Cervical Fascia.(DEC2017) 81 5 Explain formation, extent and contents of Carotid sheath.(DEC2017,AU 72 G2017,JUNE2012,,JUNE2011) 6 Investing layer of deep cervical fascia(DEC2013) 81 SHORT ANSWERS 1 Pharyngobasilar Fascia.(NOV2020) 127 2 Formation and contents of Carotid sheath(JUNE2019) 72 3 Pretracheal fascia.(JUNE2013) 82 4 Formation of external jugular vein.(JUNE2011) 105 5 Buccopharyngeal fascia.(DEC2010) 04 6 Contents of carotid sheath(DEC2010 72 ii Excel Dentistry EXCEL BDS ANATOMY ANTERIOR TRIANGLE OF NECK LONG ESSAYS 1 Describe the commencement, course, termination and branches of ex- 110 ternal carotid artery.(JUNE2019) 2 Describe the boundaries and contents of Carotid Triangle of Neck. 79 (DEC2017) SHORT ESSAYS 1 Digastric Triangle boundaries and contents(NOV2020,JULY2018,D 91 EC2016) 2 Lingual Artery origin, parts and branches.(DEC2018,DEC2015,DEC2011) 103 3 Ansa cervicalis(DEC2015,JUNE2014) 47 4 Boundaries and contents of carotid triangle(DEC2014,DEC2013) 79 5 Mylohyoid Muscle(JUNE2014) 27 6 Sternocleidomastoid.(DEC2011) 08 7 Superior cervical ganglion.(DEC2011) 09 8 Digastric muscle(DEC2010,JAN2010) 04 SHORT ANSWERS 1 Name the terminal branches of External Carotid Artery.(JUNE2010) 110 2 Mylohyoid muscle.(JUNE2012) 27 3 Ansa cervicalis.(DEC2011,JUNE2011)) 47 4 Name the Muscles supplied by Spinal Accessory Nerve(JUNE2014) 30 PAROTID REGION LONG ESSAY 1 Describe the gross anatomy of parotid gland under the following head- 67 ings. detail under the following headings: a) Location and external fea- tures. b) Relations. c) Nerve supply. d) Applied aspects.(MARCH2021,N OV2020,DEC2016,JUNE2011,AUG2017) SHORT ESSAY 1 Retromandibular vein(DEC2015,JUNE2012) 48 SHORT ANSWER 1 Parotid Duct(DEC2017,DEC2011,DEC2010) 68 Excel Dentistry iii EXCEL BDS November-2021 ANATOMY NOVEMBER 2021 ANSWERS Q1. Describe parotid gland under a) location LONG ESSAY (2 x 10 = 20 Marks) and external features, b) structures within gland, c) Structures passing out of gland, d) 1. Describe parotid gland under a) location Blood supply, e) Nerve supply and external features, b) structures within gland, c) Structures passing out of gland, Ans. d) Blood supply, e) Nerve supply a. Location and external features: 2. Classify dural venous sinuses and describe The parotid gland is present in the pyramidal cavernous sinus under (a) position, (b) re- fossa which is posterior to the ramus of the lations, (C) veins draining, (d) communica- mandible called retromandibular fossa. tions, (e) applied aspects (June 2019) The glands appears to be a three-sided pyra- mid with apex directed downwards. SHORT ESSAYS (8 x 5 = 40 Marks) An apex 3. Boundaries and contents of Digastric tri- angle. (July 2018) Four surfaces a. Anteromedial surface. 4. Gross anatomy of Submandibular gland. (June 2015) b. Posteromedial surface. c. Superior surface or base. 5. Histology of lymph node- explain with a neat labeled diagram. (Aug 2017) d. Superficial surface. Three borders 6. Fertilization. (June 2012) i. Anterior. 7. Lateral Pterygoid muscle (July 2018) ii. Medial. 8. Lacrimal apparatus. (March 2021) iii. Posterior. b. Structures within gland: 9. Nasal septum-formation, blood supply and nerve supply (June 2019) Three main structures that are present with- in it are: 10. Maxillary air sinus. (Dec 2017) 1. Facial nerve. SHORT ANSWERS (5 x 2 = 10 Marks) 2. External carotid artery. 11. Derivatives of third pharyngeal arch. (Dec 3. Retromandibular vein. 2017) 4. Parotid lymph nodes. 12. Ansa cervicalis. (Dec 2015) 5. Auriculotemporal nerve. 1. Facial nerve: 13. Labeled diagram of histology of white fi- bro cartilage. It is the superficial nerve that is situated within the gland. 14. Name the Muscles of soft palate. (Dec Entering surface: It enters through the upper 2017) part of the posteromedial surface. 15. Structures passing through foramen mag- Leaving surface: The branches move hori- num (June 2014) zontally and exits the gland through the an- teromedial surface. The five terminal branches appear as a goose-foot through the anterior border of the gland and that pattern of the facial nerve is termed pes anserinus. Excel Dentistry 131 EXCEL BDS November-2021 ANATOMY 2. External carotid artery: Nerves Entering surface: It enters through the pos- Zygomatic branch of facial nerve teromedial surface and stays in the deeper part of the gland. Inside the gland it divides Posterior auricular nerve as superficial temporal and maxillary arter- Buccal branch of facial nerve ies. Lower buccal branch of facial nerve Exiting artery: Transverse facial artery which is a branch of superficial temporal artery ex- Marginal mandibular branch of facial nerve its the gland through the anterior border of Cervical branch of facial nerve the parotid gland. Temporal branch of facial nerve 3. Retromandibular vein: Auriculotemporal nerve It is formed by the union of the superficial temporal and maxillary veins. Artery When it exits it is divided into anterior and Transverse facial artery posterior divisions. Superficial temporal vessels The anterior division merges with the facial vein to form the common facial vein. Posterior auricular artery The posterior division merges with the the d. Blood supply: posterior auricular vein forming the external Arterial supply: jugular vein. Parotid gland is supplied by external carotid 4. Parotid lymph nodes: and superficial temporal arteries. The lymph nodes draining the parotid gland Venous supply: are called as the parotid lymph nodes. Parotid gland is drained by retromandibular More specifically, it can refer to: deep pa- and external jugular veins. rotid lymph nodes. superficial parotid lymph nodes. e) Nerve supply: 5. Auriculotemporal nerve: Three types of nerve supply the parotid gland The auriculotemporal nerve is a branch of the mandibular nerve that provides sensa- Parasympathetic tion to several regions on the side of head, including the jaw, ear, and scalp. Sympathetic c. Structures passing out of gland Sensory fibres: Parotid Duct (Stenson’s Duct): The parotid a. Parasympathetic supply: duct, or Stensen duct,is the duct draining It is supplied via auriculotemporal nerve. the salivary gland. Inferior salivatory nucleus It is the route that saliva takes from the ma- jor salivary gland, the parotid gland, into the ↓ mouth. Glossopharyngeal nerve It runs forward along the lateral side of the ↓ masseter muscle. Tympanic branch In this course, the duct is surrounded by the buccal fat pad. ↓ It takes a steep turn at the border of the Tympanic plexus masseter and passes through the buccina- tor muscle, opening into the vestibule of ↓ the mouth that opens in front of the second Lesser petrosal nerve Maxillary molar tooth. ↓ 132 Excel Dentistry EXCEL BDS November-2021 ANATOMY Otic ganglion. ↓ Auriculotemporal nerve ↓ Parotid gland ↓ Produces watery secretion. b. Sympathetic supply: Supplied by: Plexus around external carotid artery from superior cervical sympathetic ganglion. Preganglionic sympathetic fibres: Begin from lateral horn of T1 spinal segment. c. Sensory supply: It is derived from: Auriculotemporal nerve. Great auricular nerve Q13. Labeled diagram of histology of white fibro cartilage. Excel Dentistry 133  Nov - 2021 EXCEL BDS Physiology It inhibits the transformation of prothrombin to NOV 2021 thrombin. LONG ESSAY (1 x 10 = 10 Marks) It is accompanied by a plasma cofactor albumin X 1. Describe the intrinsic pathway of It leads to the neutralization of thrombin on coagulation. (Dec 2016) Add a note on fibrinogen. anti-coagulants. The use of anticoagulants: SHORT ESSAYS (3 x 5 = 15 Marks) It is a decision based upon the risks and benefits 2. Describe the short-term regulation of blood of anticoagulation. pressure. (Aug 2017) The uses are: 3. Explain the mechanism of oxygen trans- Atrial fibrillation — commonly forms an atrial port in the blood. appendage clot. Coronary artery disease 4. List the properties of synapse. Explain any two of them. Deep vein thrombosis — can lead to pulmonary embolism SHORT ANSWERS (5x2=10 Marks) Ischemic stroke 5. Define hypoxia. Mention its types. (June Hypercoagulable states 2019) Mechanical heart valves 6. List the components of juxta glomerular Myocardial infarction apparatus. Mention its function. 7. List four functions of saliva. (June 2019) Q3. Explain the mechanism of oxygen transport in the blood. 8. List the changes in eyes during accommo- Ans: dation. Oxygen is carried in the blood in two forms such 9. List the hormones regulating serum cal- as the cium level. (Aug 2017) a. Dissolved in plasma. ANSWERS b. Reversibly bound to hemoglobin (about 97% of the total). Q1. Add a note on anti-coagulants. a. Dissolved in plasma Ans: Only a small amount of oxygen is dissolved in Anticoagulants, commonly known as blood plasma since oxygen has such a low solubility. thinners, are chemical substances that prevent or reduce coagulation of blood, prolonging the At elevated PO2 (breathing 100 % oxygen or clotting time. during hyperbaric oxygenation), however, the physically dissolved form of oxygen can become The commonly used anticoagulants are hepairin. significant. Heparin is used in vivo and in vitro. Henry’s law states that the amount of oxygen Heparin is chemically a mucoitin polysulphuric dissolved in plasma is directly proportional to acid. PO2. It is secreted by the mast cells. b. Reversibly bound to hemoglobin (about 97% Mechanism of action: of the total). 76 Excel Dentistry EXCEL BDS Nov - 2021 Physiology The protein hemoglobin is a molecule which is When nerve fibers of different pre­synaptic responsible for carrying almost all of the oxygen neurons end on a common postsynaptic neuron, in the blood. this is known as convergence. It is composed of four subunits, each with a In CNS, on an average about 10000 synapses are heme group plus a globin chain. found on any one neuron. The heme group is composed of a porphyrin ring g. Summation: which contains an iron (Fe) atom in its center. When a stimulus of subthreshold strength is Normally, the Fe is in the +2 redox state (ferrous) applied, there will not be development of action and can reversibly bind oxygen. potential in postsynaptic region. There are at least six genes that control globin But if many subthreshold stimuli are applied synthesis in humans, resulting in the formation at pre­synaptic region, effects of these stimuli of six structurally different polypeptide chains. can get added up and lead to action potential development in postsynaptic region. This is The blood of a normal adult human contains known as summation. at least six different species of hemoglobin molecules, all of which have the same principal There are two types of summation namely structure and function. spatial and temporal. In temporal summation, pre­synaptic neuron stimulated will be same, Hemoglobin A (A for adult) makes up 92% of but many stimuli are applied in rapid succession the total hemoglobin concentration in a normal (timing of stimuli will be different, but place of adult human. stimulation will be same). Hemoglobin A (HbA) is composed of two α In spatial summation, presynaptic neurons chains and two β chains, symbolically written as stimulated will be different but stimuli will be α2 β2. applied simultaneously (time of stimulation Oxygen-haemoglobin Dissociation curve (Dec shall be same, but places of stimulation will be 2016) different). This is possible because of the property of Q4. List the properties of synapse. Explain any two convergence. of them. Ans: Short answers Synapse, also called neuronal junction, the Q6. List the components of juxta glomerular site of transmission of electric nerve impulses apparatus. Mention its function. between two nerve cells (neurons) or between Ans: a neuron and a gland or muscle cell (effector). Juxtaglomerular Apparatus The properties are: The juxtaglomerular apparatus is a specialized a. One-way conduction (unidirectional conduction) structure formed by the distal convoluted b. Postsynaptic Potentials tubule and the glomerular afferent arteriole. c. Synaptic Delay It is located near the vascular pole of the d. Synaptic Inhibitor glomerulus. The main function of the apparatus is the secretion of renin, which regulates e. Fatigability systemic blood pressure via the renin- f. Convergence and divergence: angiotensin-alodosterone system. Impulses from one pre­synaptic nerve fiber may The juxtaglomerular apparatus is composed of: end on postsynaptic region of large number a. Macula densa, a collection of specialized epithelial neurons and this is called as divergence. Excel Dentistry 77  Nov - 2021 EXCEL BDS Physiology cells of the distal convoluted tubule. These cells are enlarged as compared to surrounding tubular cells. The cells of the macula densa sense sodium chloride concentration in the tubule, which in turn reflects the systemic blood pressure. b. Juxtaglomerular cells of the afferent arterioles, which are responsible for secreting renin. These cells are derived from smooth muscles cells of afferent arterioles. c. Extraglomerular mesangial cells, which are flat and elongated cells located near the macula densa. Their function is currently unclear. Q8. List the changes in eyes during accommodation. Accommodation is the process by which the vertebrate eye changes optical power to maintain a clear image or focus on an object as its distance varies. In this, distances vary for individuals from the far point—the maximum distance from the eye for which a clear image of an object can be seen, to the near point—the minimum distance for a clear image. The changes observed are: Change in focal length because there is contraction in the ciliary muscle. Cornea being a fixed structure and its curvature is constant along with its refractive power is constant. Poster surface of lens curvature does not change. Suspensory ligaments is relaxed with the tension exerted on the lens capsule. 78 Excel Dentistry EXCEL BDS November-2021 BIOCHEMISTRY NOVEMBER 2021 LONG ESSAY (1 x 10 = 10 Marks) 1. Discuss Glycogenesis (July 2018) and Gly- cogenolysis. (Dec 2013) Add a note on Von Gierke’s disease. (June/July 2012) SHORT ESSAYS (3 x 5 = 15 Marks) 2. Phospholipids. (Dec 2016) 3. Biochemical functions and deficiency manifestations of Vitamin D. (July 2018) 4. Creatinine clearance test. (Dec 2018) SHORT ANSWERS (5 x 2 = 10 Marks) 5. Phenylketonuria. (Dec 2018) 6. Name two (2) plasma proteins and give their function. (March 2021) 7. Dietary Fibers. (June 2019) 8. Features of Genetic code. (June 2011) 9. Mention the normal serum levels of a) Phosphorous (Nov 2020) b) Cholesterol. ANSWERS Q9. Mention the normal serum levels of a) Phosphorous (Nov 2020) b) Cholesterol. Ans: Normal value: Normal level of cholesterol in serum is 150- 220 mg/ di. Clinical significance: Increased serum cholesterol level is the ma- jor risk factor in promoting atherosclerosis. 70 Excel Dentistry EXCEL BDS November-2021 DADH NOVEMBER 2021 ANSWERS Q5. Ground section LONG ESSAY (2 x 10 = 20 Marks) Ans. 1. Discuss in detail chronology and morphol- A section of bone or tooth prepared for his- ogy of permanent mandibular 1st molar tological study by polishing until thin enough (REFER TABLE-PAGE NO-382) for microscope viewing is called ground sec- tion. 2. Enumerate and write in detail hypocalci- Ground sections of teeth or bone are consid- fied structures of enamel. (July 2015) ered best solutions for the study of any hard tissues in the study of histopathology. SHORT ESSAYS (8 x 5 = 40 Marks) Ground sections of teeth are sections pre- 3. Development of mandible. (June 2014) pared without using any chemical and main- taining its anatomy 4. Interglobular dentin (March 2021) Apparatus used for ground section of teeth are: 5. Ground section Extracted Teeth Electrical lathe machine (High and Low 6. Theories of mineralization (Dec 2017) speed): Grounding done till 4-5mm thick- ness. 7. Discuss in detail lingual aspect of perma- nent maxillary canine (REFER TABLE-PAGE Carborundum stone (Rough, Static, Fine). NO-374) Procedure: 8. Regressive changes of pulp (June 2019) Teeth are first soaked in 20% formaldehyde for 24 hours. 9. Histology of maxillary sinus (July 2018) Washed in water. 10. Histology of mucous acini (Aug 2017) Tooth could be sectioned to any thickness by using Ultra-microtomes with diamond cut- SHORT ANSWERS (5 x 2 = 10 Marks) ting blades. Using electrical lathe machine also grind- 11. Bundle bone (July 2015) ing could be done and equally both sides grounded, thus preparing a thin ground sec- 12. Dental papilla derivatives (June 2013) tion. 13. Non-keratinocytes (June 2019) Continuous spray of water is required, as tooth gets heated up due to friction of grind- 14. Oblique ridge (Dec 2015) and triangular ing. ridge (Dec 2010)(Pg 366) Tooth is grounded at high speed until 4-5 mm thickness is done. At low speed further 15. Cementoenamel junction (June 2019) grounding is done till 3-4 mm thickness is achieved. Manually grounding can be done in two steps, first using rough carborundum stone till a section of 2- 3mm is obtained and then using a static carborundum stone till a sec- tion thickness of 1mm is obtained. Grinding is further continued using fine car- borundum stone till a section thickness of 0.25mm is obtained. Continuous water is poured on this stone, due avoid friction of heat. 110 Excel Dentistry EXCEL BDS November-2021 DADH Finally, the grounded section is cleaned in xylene for one minute. The dried section is then mounted on microscopic slide using DPX and viewed under microscope. Merits and demerits Cost Restriction: Availability of ultra microtomes with diamond cutting blades. Using burs have their own disadvantage: Leads to some anatomical changes when teeth are grounded. Electrical Lathe and hand grinding is well suited. Instruments available are low cost and easily available. Carborundum stone used by dental surgeon are 4-5 cm diameter. Grinding of teeth with small surface is a problem with fatigue and not possible. Hand grinding is really injurious to the fingers. Fingers are also rubbed on the rough surface lead- ing to injuries. Excel Dentistry 111 TO PURCHASE THE BOOK CLICK HERE