1. Maxillo mandibular relation records
JAW RELATION
It is defined as “Any relation of the mandible to the maxilla”
Types Vertical jaw relation
2. Horizontal jaw relation

2. Orientation of occlusal plane
The occlusal plane is defined as imaginary plane established by the incisal and occlusal surfaces of the teeth".

3. Importance of orientation of occlusal plane
1.Anteriorly, occlusal plane mainly helps in achieving esthetic & phonetic.
2.posteriorly, it forms a milling surface, where tongue & buccinator muscle are able to position the food bolus onto it , and hold it there during mastication.
Incorrect of occlusal plane would hamper esthetics, phonetics, & mastication. It may affect stability of complete denture & ultimately result in alveolar bone resorption.

4. The vertical length of the maxillary occlusion rim
Anteriorly extend 2mm below relaxed lip& oriented to be parallel to inter pupillary line.
Posteriorly the vertical length and occlusal plane are made to be coincide with (Camper's line).
(Camper's line, ala-tragus line) line passing from the lowest point of the ala of the nose to the center of the tragus of the ear.

5. The vertical length of the mandibular occlusion rim
Anteriorly the level of mandibular occlusion rim with the level of the lower lip.
Posteriorly the vertical length of the rim with level of the retromolar pad.

6. Orientation of occlusal plane
Anteriorly the maxillary occlusal plane is adjusted to be parallel to interpupillary line.
Done using fox plane

7. Vertical relations

8. Vertical relations
Rest vertical dimension The distance between two selected points one on the fixed part (maxillae) and one on the movable part (mandible) when the maxillofacial musculature is in a state of tonic equilibrium.
Occlusal vertical dimension : the distance between two selected points one on the fixed part (maxillae) and one on the movable part (mandible) when occluding members (teeth) are in contact.

9. Rest vertical dimension
Occlusal vertical dimension

10. Evaluating vertical dimension
The inter occlusal distance (free way space) is the distance or gap existing between the upper and the lower teeth when the mandible is in the physiological rest position. It is usually 2-4 mm when observed at the position of the first premolars.
The closest speaking space is the closest relationship of the occlusal surfaces and incisal edges of the mandibular teeth to the maxillary teeth during function and rapid speech ,its about 1-2mm.

11. There are many of factors that affect the measurement of vertical dimension which is:
1. Patient must sit in upright position with head unsupported.
2. Any tension should be avoided.
3. Special attention and enough time should be given to those patients having neuromuscular disorder.
4. No valid method for all patients, so it is advisable to use several methods and compare the result

12. Methods of recording the rest vertical dimension
A-(physiological methods):
Facial measurements (reference points)
Tactile sense (opening closing)
Phonetics (em)
Facial expression (skin tone and the lips contour)
Anatomic land marks (Willis guide)

13. FACIAL MEASUREMENTS AFTER SWALLOWING AND RELAXING
Patient is asked to sit upright and comfortably, eyes looking straight ahead.
Insert maxillary occlusal rim.
Place 2 points of reference.
Instruct the patient to wipe his lips with his tongue, to swallow and to drop his shoulders – rest position.
Measure - repeat and take average.
Tactile sense
Instruct the patient to stand erect and open the jaws wide until strain is felt in the muscles.
When the opening becomes uncomfortable, ask him to close slowly until the jaws reach a comfortable relaxed position.
Measure the distance and compare it.

14. Facial expression Speech
2 methods:
1st method :
Ask the patient to repeatedly pronounce the letter ‘M’, a certain number of times. Distance is measured immediately after the patient stops.
2nd method:
keep talking to the patient and measure the distance immediately after the patient stops talking.
Facial expression
Patients jaw will be in rest position when he is relaxed.
Skin around the eyes and chin should be relaxed.
Nostrils are relaxed and breathing is unobstructed.
Upper and lower lips have slight contact in one plane.

15. Anatomical Land Mark:
Measurement of a fixed landmark of the face by a special scale called the sorenson profile scale. The Sorenson Profile Scale measurement was taken by placing the nasion locator of the instrument firmly in the depression at the bridge of the nose and raising the chin seat until it lightly touched the most inferior and anterior border of the chin. Or by using Willis bite gauge which is designed to measure the distance from the pupil of the eye to the rima oris and the distance from the nasal spine to lower border of the mandible when measurement is equal the jaw at rest.

16. Methods of recording the occlusal vertical dimension (mechanical methods):
Pre-extraction records
Profile photographs
Radiography (cephalometric profile and the condyles in the fossae)
Articulated cast
Facial measurements
Former dentures
Edentulous patients (wax occlusion rims)
Patients tactile sense
Swallowing followed by relaxing
Phonetics (3, 33) (5,55) ( Emma )

17. Facial Measurements:
Tatoo points are marked on tip of the nose and base of the chin. The vertical dimension between the anatomic landmarks is then compared with that of patient to avoid errors. Willis gauge is also used to measure facial dimension . One arm contacts the base of the nose and the other arm contacts the base of the chin.
Measurement of the former dentures:
A Boley’s gauge is used to measure the distance between the border of the max and mand denture ,when the dentures are in occlusion.This measurement is used to determine the VDO.

18. Phonetics and esthetics.
The dentist asks the pt to speak certain words and then makes certain observations of the relationship of the occlusion rims to each other and to the lips.
Using ‘m’sound:
The pt repeats the letter ‘m’. When the lip just touches ask the patient to hold the jaws still. The distance between tip of the nose and chin is measured (VDR).The occlusion rims are adjusted and again measured. The second measurement should be 2-4mm less than the first measurement(VDO)

19. SILVERMAN’S CLOSEST SPEAKING SPACE
The ch,s,and j sounds:
There should be 1mm space between the occlusion rims in the anterior area at correct VDO.
Using 33 :
When repeating this word there should be enough space for the tip of the tongue to protrude between the anterior teeth.
Using f or v sounds:
The max incisors/occlusion rims should lightly contact the lower lip at the vermillion border when pt pronounces these words.
SILVERMAN’S CLOSEST SPEAKING SPACE
The 2mm space between the incisors at correct VDO when pt pronounces words containing ‘S’ eg.
The closest speaking space measures vertical dimension when the mandible and muscles involved are in physiologic function of speech.

20. Swallowing threshold.
The technique is based on the fact that when a person swallows, the teeth come together with a very light contact at the beginning of the swallowing cycle. If the occlusion rims do not come into contact during swallowing then the VDO is less.
ESTHETICS
In normal relaxed position the lips are even anteroposteriorly and in slight contact. If the face appears strained the vertical height may be more. If the corners of the mouth droop, making the chin appear too close to the nose, then vertical dimension may be too less.

21. Clinical steps in recording JR
Properly contoured maxillary occlusal rim is inserted in the patient’s mouth and following are assessed
Lip support: Upper lip should just supported enough.
Visibility of the rim: at rest 0.5 – 1.0 mm of the
rim should be visible
Touches wet line of lower lip when pt says F or V sounds
Ask patient to from Count
Lips relaxed
Naso labial angle should be at 90 degree
Philtrum should be
depressed slightly, There should be
no obliteration or streching of philtrum

22. Orientation of occlusal plane
Anteriorly the maxillary occlusal plane is adjusted to be parallel to interpupillary line.
Done using fox plane

23. Posteriorly the occlusal plane is adjusted to be parallel to alae-tragus line(camper’s plane)
Camper’s plane: Imaginary line joining the alae of the nose to the tip of the tragus

24. For mandibular occlusal rim
Anteriorly the occlusal plane should be at the corner of the mouth
Posteriorly the occlusal rim should be at the junction of anterior 2/3rd and posterior 1/3rd of the retromolar pad.

25. Mark two points …
One at tip of nose and one at tip of chin.
Make patient sit upright comfortable position in dental chair with head unsupported.
Patient is to asked swallow and relax and drop his shoulders.
Once dentist is sure that patient relaxed, the distance between two points are measured. This measurement is for vertical at rest.
Usually 2 or 3 readings are taken… the average is taken as reading. This prevents error during taking measurements.

26. now.. The mandibular occlusal rim is inserted and patient is asked to bite on the rims.
With patient in this occluding position, readings at same two points marked earlier is made.
This measurement is vertical at occlusion.
Usually the VDO should be 2-4 mm less than VDR.
2. Ask the patient to say words with "S" sounds, such as 77 ,Sunset Strip, 66, count from 1-10, or from

27. Observe from the profile and frontal view that there is 1-2 mm of clearance between the incisal edges of the occlusion rims in the midline when the patient repeats the words containing "S" sounds.  The space that exists when these words are said is called the closest speaking space. 
If there is a space of 1-2 mm between the incisal edges of the maxillary and mandibular occlusal rims in the midline when the patient says an "S" sound, there should be adequate interocclusal distance. 
If the occlusion rims contact when these words are said, then wax on the mandibular occlusion rim should be removed until this clearance is obtained.  
When you are satisfied that the vertical relation of occlusal you have established is correct for your patient and your occlusion rims occlude evenly anteriorly and posteriorly, you are ready to record centric relation.