Important classifications & tabular columns in Complete Denture

 

1. Classification of Soft palates:

Class 1	Horizontal & demonstrates little muscular movement. Most favourable condition, as it allows more tissue coverage for the palatal seal.
Class 2	Soft palate makes 45° angle to the hard palate. Tissue coverage for posterior palatal seal is less than that of class 1 condition.
Class 3	Soft palate makes 70° angle to hard palate. Tissue coverage for posterior palatal seal is minimum. A ‘V’ shaped palatal vault is usually associated with class III soft palate.

2. Classification of lateral throat form (retromylohyoid fossa):

Class 1 (deep)	It indicates that the anatomical structure will accommodate a fairly long and wind flange. Ideal throat form.
Class 2 (moderate)	It is about half as long and narrow as class 1 and twice as long as class 3.
Class 3 (shallow)	Class III has minimum length of thickness. The border usually ends 2-3 mm below the mylohyoid ridge.

3. House classification of tongue size:

Class 1	Normal size, development and function. Sufficient teeth are present to maintain this normal form.
Class 2	Teeth have been absent long enough to permit a change in the form and function of tongue.
Class 3	Excessively large tongue.

4. Wright's classification of tongue position:

Class 1	Tongue lies in the floor of the mouth with tip forward and slightly below the incisal edges of the mandibular anterior teeth. Ideal position of the tongue.
Class 2	The tongue is flattened and broadened but the tip is in a normal position.
Class 3	The tongue is retracted and depressed into floor of the mouth, with the tip curled upward or assimilated into the body of the tongue.

5. Stress bearing area of maxilla & mandible.

6. Mouth movements and their corresponding condylar movement.

Movement	Working condyle moves
Laterotrusion	Laterally and outwards
Laterosurtrusion	Laterally and upwards
Laterodetrusion	Laterally and downwards
Lateroprotrusion	Laterally and forwards
Lateroretrusion	Laterally and backwards

7. Difference between closest speaking space & freeway space.

Closest speaking space	Freeway space
Described by Silverman	Described by Thompson and niswonger
Closest speaking space measures the vertical dimension when the mandible and muscles involved are function of speech. It is the space between upper and lower teeth when sounds like eh, s, j are pronounced	It establishes vertical dimension when the muscles and mandible are in rest position.
It is dynamic position established when muscles are in state of function.	It is static position established when muscles are in state of rest.
It is about 1-2mm, when measured in the premolar area	It is about 2-4mm when measured in the premolar area
The speaking space increases when there is small vertical dimension	The freeway space increases when there is reduced vertical dimension.

8. Clinical features of increased & decreased vertical dimension.

Increased vertical dimension	Decreased vertical dimension
Decreased freeway space (Normal range= 2-4mm) Pain and clicking in the TMJ. Diffuse pain on ridge. Reversible soft tissue changes and irreversible ridge resorption. Increased lower facial height. Cheek biting Stretching of facial muscles.	Increased freeway space Sagging of the corners of the mouth Thinning of lips Obstruction of eustachian tube. Muscular imbalance Facial height decreases Angular cheilitis.

9. Classification of articulators:

Class I (Simple holding instruments capable of accepting a single static registration)	Eg: Slab articulators, Hinge joint, Barndor, Gysi simplex.
Class II (Instruments that permit horizontal as well as vertical motion but do not orient the motion of TMJ via face bow transfer)	Class IIa- Eccentric motion permitted based on average or arbitrary values. Eg: Mean value articulator. Class IIb- Limited eccentric motion is possible based on theories of arbitrary motion. Eg: Monson’s, Hall’s articulator. Class IIc- Limited eccentric motion is possible based on engraving records obtained from the patient. Eg: House’s articulator.
Class III (Permit horizontal, vertical positions and also accept face bow transfer.	IIIa- Accept a static protrusive registration and they use equivalents for other types of motion. Eg: Hanau H, Dentatus. IIIb- They accept static lateral registration and they use equivalents for other types of motion. Eg: Ney, Teledyne Haunau University series, Trubite, Panadent.
Class IV (They accept 3-dimensional dynamic registration)	IVa- The condylar path registered cannot be modified. Eg: TMJ articulator, stereograph. IVb- They allow customization of the condylar path. Eg: Stuart instrument gnathoscope, pantograph, Denar.

10. Treatment for deflective contacts in both anterior and posterior teeth.

Deflective contacts	Occlusal correction
Posterior teeth 1.Deflective contact is only in centric relation 2.Deflective contact is both in centric and eccentric positions	-Reduce fossa or marginal ridge -Reduce both fossa and cusp.
Anterior teeth When incisal edge of lower anterior touching the maxillary lingual fossa in centric relation only.	Reduce the lower incisal edges.
Incisal edge of lower anteriors touching the maxillary lingual fossa both in centric and eccentric relations.	Deepen the lingual fossa of upper teeth and reduce the incisal edges of lower teeth.
Deflective contacts occurring on working side	BULLS law- Upper buccal cusp & lower lingual cusp made shorter without deepening the central fossa.

For Atwood's classification of root resorption, click the link below...

https://www.blogger.com/blog/post/edit/4923003805564511941/6330678008591988062

If I missed any classification, let me know in the comment section.

Notes on Residual ridge resorption for basic understanding and also useful for NEET MDS exam.

 Before going into impression techniques and jaw relation, you should know some points about surfaces, residual ridges and stress bearing areas.

Surfaces of complete denture:

3 surfaces

Impression surface-Intaglio surface

Fit of denture depends on accuracy of this surface.

Contributes to retention, stability, and support of the denture.

Polished surface-cameo surface

External surface of denture without the teeth.

Should correspond to the contours of lips, cheek and tongue.

Contributes to retention and stability of denture.

Occlusal surface- 

Aids in mastication and directs forces of mastication to the supporting tissues.

Contributes to stability of denture. 

Residual ridge resorption:

The diminishing quantity and quality of residual ridge after teeth removed (GPT8).

Reduction of volume and size of residual alveolar process of mandible and maxilla.

Atwood classified progression of residual ridge resorption as follows:

Order 1: Pre-extraction

Order 2: Post extraction

Order 3: High, well rounded

Order 4: Knife-edged

Order 5: Low, well-rounded

Order 6: Depressed.

Generally, women show more resorption than men.

During first year of extraction- 2-3mm reduction seen in maxilla, 4-5mm for mandible.

After this the intensity will get reduced.

Annually, Mandible shows 0.1-0.2mm resorption, four times more than edentulous maxilla.

Pattern of maxillary ridge resorption is centripetal i.e., upward and palatal direction.

Resorption of mandible anterior ridge occurs in downward(vertical) and lingual direction.

For mandibular posterior ridge- centrifugal direction i.e., downward (vertical) and buccal direction.

The main ratio of anterior maxillary residual ridge resorption to anterior mandibular ridge resorption is 1:4.

Factors affecting RRR:

Treatment:

• Maintenance phase comprising of relining and rebasing the dentures is essential throughout the life of a CD patient.
• Overdentures help in minimizing ridge resorption and contribute towards enhanced retention, stability, support of prosthesis along with preservation of proprioception. Clinicians must try to retain residual root whenever possible.
• A severely resorbed ridge may require vestibuloplasty, but prosthetic rehabilitation with osseointergrated implants is the best solution to prevent this process and preserve the bone.
  
  
  

Points to remember:

1. Extreme bone resorption results in the mental foramen opening directly at the crest of residual bone process. Pressure from the denture against the mental nerve and over thin sharp bone will cause pain.

2. Round ridge with parallel sides provides good support and good stability.

3. Patients with large tongues often experience poor lower denture stability.

4. Thick pasty saliva is due to reflex sympathetic stimulation of salivary glands and watery saliva is due parasympathetic stimulation.

5. Excessive amount of thick ropy saliva and lack of saliva decreases the denture retention.

6. Epulis fissuratum is soft tissue reaction that appears in the sulcular region due to over extension of the denture flanges. Treated by shortening and smoothening the denture border.

7. Papillary hyperplasia results from candidal infection and improper relief of the palatal area in complete dentures. Small lesions are treated by curettage and large lesions are treated by split thickness supraperiosteal excision.

8. Treatment of choice for bilateral soft tissue tuberosity undercut is removal of tissue undercut on one side so that the undercut on other side helps in retention.

9. Treatment of choice for bilateral bony tuberosity undercuts is removal of both the undercuts such that no bony undercut exists.

10. All mandibular tori should be excised because the mucosa over the tori is more prone to irritation due to constant movement of the denture during mastication.

11. Maxillary tori should be removed if it- 

• Extends to posterior palatal seal region.
• Interferes with speech.
• Causes poor denture stability.

12. Mandibular lingual tori mostly occur in premolar region.

13. Soft flabby tissue is undesirable because it affects the stability of denture. If not excessive, it can be managed by suitable impression procedures, in extreme cases it should be removed surgically.

14. 33% of edentulous moths have retained root tips.

How & What to read in biochemistry for NEET MDS preparation.

 Hello aspirants! I Hope you all are doing good...

You may be worrying about 'how to prepare biochemistry?' and 'what topic should cover?'. Many students try to avoid this subject because the fear of remembering not actually the subject is really tough.

The key is whatever you are going to prepare or prepared already, you just have to revise the topic not every day, just alternative days. 

On first read, you are going to learn the topic or cycle, on second read you are going to memorize, on third time, you should try to remember without seeing book or notes, then you will find in which step you are weak, then repeat the revision once again. The reason why revision important is every time you revise the topic, you will learn new things & explore new concept.

Try to do the revision, 10 days once or monthly once, you will remember it for long period, until your final exam. And just spend adequate time, don't overdo it, because this is not the only subject which comes for exam.

What to read in biochemistry:

Start with three common metabolisms.

1. Carbohydrate metabolism.

2. Protein metabolism.

3. Lipid metabolism.

In these topics complete the cycles i.e., Glycolysis, glycogenesis, glycogenolysis, gluconeogenesis, urea cycle, citric acid cycle, cholesterol synthesis, Fatty acid synthesis, Ketone bodies, bile acid synthesis, HMP pathway, Rapaport-leubering cycle. (If i missed any other cycle please add it in your to do list).

After reading the cycle, go back to dental pulse, complete the MCQ's & synopsis of these topics, then you will be thorough.

For remaining topics like, 

Vitamins, enzymes, nucleoproteins & mineral metabolism, general biochemistry, from my personal experience I can say that dental pulse & class notes are enough.

Textbook or dental pulse?

Nobody can tell that only textbooks or only MCQ books are enough, for each topic it differs. For cycles you should go through the textbooks, because that's the core topics of biochemistry, & for remaining topics first read the synopsis then go for MCQ's and read explanation for every question carefully, you will get an idea about it. 

And finally, revising the test papers plays major role in preparation. Reading MCQ book itself, going through the past question papers, but if you attempted test series, it would give you the confidence and better understanding.

Last but not the least, don't plan to give up on entire subject if you have adequate time for your exam, you can't master the textbook, but instead try to master any MCQ book. I am not misleading you, but if we don't have enough time we should think smart.

ALL THE BEST FOR YOUR EXAMS!

How will the anti-diabetic drugs work? Implication in dental procedure.

 

1. What is diabetes mellitus?

A metabolic disorder characterized by hyperglycemia, glycosuria, hyperlipidemia, negative nitrogen balance and sometimes ketonemia.

PATHOLOGICAL CHANGES:

Thickening of capillary basement membrane, increase in vessel wall matrix and cellular proliferation resulting in vascular complications like lumen narrowing, early atherosclerosis, sclerosis of glomerular capillaries, retinopathy, neuropathy and peripheral vascular insufficiency.

Two major type of diabetes mellitus are:

Type 1 [Insulin-dependent diabetes mellitus/ Juvenile onset diabetes mellitus]:

Type 2 [Noninsulin-dependent diabetes mellitus (NIDDM)/ maturity onset diabetes mellitus]:

2. Anti-diabetic drugs Classification:

3. How the Antidiabetic drug will act?

(A)

(B)

                (C)                          

 (D)

(E)

                                                                 

                                                                   (F)

4. Indications of oral hypoglycemic:

Indicated only in type 2 diabetes.

Most useful in patients with-

1. 40+ years at onset of disease.

2. Obesity at the time of presentation.

3. Duration of disease < 5 years when starting treatment.

4. Fasting blood sugar < 200 mg/dl.

5. Insulin requirement < 40 U/day.

6. No history of ketoacidosis, or any other complication.

Current recommendation is to institute metformin as soon as diagnosis of type 2 DM.

DPP-4 inhibitors are second line/ add on antidiabetic drugs.

5. Implications in dentistry:

• Dental extractions & other simple procedures under local anesthesia do not pose any special problems in diabetics, if blood sugar levels are well controlled.
• For more extensive dental procedures under GA, it is advisable to monitor urine & blood sugar levels & cover the perioperative period with regular insulin injected subcutaneously.
• Severe or uncontrolled diabetics may be given an i.v. infusion of regular insulin along with 5% glucose solution during the procedure.
• If blood sugar level poorly controlled prophylactic antibiotics should be given to cover dental procedure.

How to prepare pharmacology for NEET MDS exam.

 Preview:

1) Points to remember before starting your preparation.

2) Topics to cover in pharmacology.

3) Which is best resource- MCQ book or textbook.

4) How to remember this evaporating subject.

Perfect Plan to prepare for NEET MDS for last 60 days.

 

You may have started your preparation months back, but when exam is nearer your anxiety and depression will grow up on you. Be calm and have a customized plan. It may sound unrealistic, & of course within 60 days you can't complete everything perfectly, but if you utilize every single minute, and believed that it will work, you can cover as many topics as possible within 60 days. 

And to be honest I want to tell you one thing, if you have started your preparation earlier, I means 9 months or 6 or 12 months back you should give importance to every topic. But if you are nearer to your exam, you should be smart enough to plan accordingly. 

Important point: regretting is a waste of time.

Never ever think that you didn't start your preparation early, or wasted lot of time etc., there is no time for your sob story if your exam is within 2 or 3 months. Definitely you may have touched your dental pulse or any other MCQ books before. For next above or within 60 days you are just going to stick to your MCQ books. Of course, referring standard textbooks is good thing, but this is not right time to start with it. If you have already referred any standard textbooks, then you should start revising it now.

4 important points to keep in mind:

1. Keep your mind calm- the most important thing you should follow until you finished your exam. Because in 3 hours duration at the exam hall you should be in your right mind to click the right answer. Because even if you know the answer, sometimes you tend to click the wrong one if you are anxious. so please be calm and study continuously until you write the exam.

2. Be consistent- Read & revise every day without fail. Even if you got less marks in your test series, please don't mind. because i have seen many of my friends who secured average marks in test series but in final, they secured rank within top 200. Life is unpredictable. No one is God, so your present marks can't tell your final results, it will reflect your yesterday's preparation.

3. Have a customized plan- Everyone have different style of study pattern. Some are single subject reader that mean for entire day they can read only one subject; some are multiple subject reader they can read two or more subjects in a day. But restricting to 2 subjects is good idea. Most importantly don't mess up your sleep pattern.

4. Never doubt yourself- just read, revise and continue with your studies.

Here I will provide you study plan if you find it reliable you can follow or you can customize your own:

Among 60 days or two months divide your days into 10s. Make your plan for first 10 days and repeat it for remaining 5 ten portions. Totally you could revise it for 5 times if you used efficiently.

As I mentioned earlier you can't afford for standard textbooks at last minute so stick to your DENTAL PULSE or TARGET or whatever MCQ books you have, but pulse will be better.

So here I made a plan for 1st 10days- [ key point is you should finish dental pulse as much as possible]

Divide your day into two major portions and one small portion for test paper. 

[The time mentioned below is an example, you can follow your own timing]

Day 1- 6 am to 1 pm go for oral pathology Of Course this subject is vast in mcq book, you can't complete but try as much as possible just read the mcqs and go through the explanation. 2 pm to 8pm go for radiology as this subject is not so big you can finish it fast.

Day 2- 6am to 1pm oral surgery, 2pm to 8pm dental histology.

Day 3- 6am to 1pm ortho, 2pm to 8pm pedodontics, these two subjects are related so you can finish mostly.

Day 4- 6am to 1pm prosthodontics, 2pm to 8pm dental anatomy.

Day 5- 6am to 1pm Dental material, 2pm to 8pm conservative dentistry.

Day 6- 6am to 1pm Endodontics, 2pm to 8pm periodontics.

Day 7- 6am to 1pm Biochemistry, 2pm to 8pm General pathology.

Day 8- 6am to 1pm Microbiology, 2pm to 8pm general surgery.

Day 9- 6am to 1pm Physiology, 2pm to 8pm general medicine.

Day 10- 6am to 1pm community dentistry, 2pm to 8pm the remaining topics of subjects which you didn't finish, choose accordingly. 

In above timetable I didn't mention about anatomy and pharmacology, because you can't finish it within a day, so divide the topics of both subjects and finish that for 10days from 9pm to 11pm or its better to start early like 5am to 9am and remaining time divide for two subjects as mentioned above, based on your preference.

For 10-20 days repeat this, choose your own order and finish the unfinished topic which you can't study in first 10 days.

For 20-30 days, repeat your study plan in reverse order that means first go for nonclinical subject then clinical subject.

And repeat this study until 50th day of your preparation. Revision is the key

 In last 10 days give major portion to your test series and clinical mcqs, but don't forget to finish dental pulse. I am not saying that you should ignore the nonclinical but give you can't unfinish any of the clinical subjects.