Wolff’s law

WOLFF’S LAWWOLFF’S LAW

INDIAN DENTAL ACADEMY

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In the early 1990s German In the early 1990s German physiologist Wolff demonstrated that physiologist Wolff demonstrated that bony trabeculae were arranged in bony trabeculae were arranged in response to stress lines on the bone.response to stress lines on the bone.

Bone is formed in just the quantity Bone is formed in just the quantity and shape that will enable it to and shape that will enable it to withstand the physical demands withstand the physical demands made upon it, with the greatest made upon it, with the greatest amount of economy of structure.amount of economy of structure.


If a long bone such as the femur is If a long bone such as the femur is cut open, it will be found that dense cut open, it will be found that dense cortical bone is on the outside and cortical bone is on the outside and the spicules of cancellous bone the spicules of cancellous bone within are arranged in such a way within are arranged in such a way that they support the cortical bone that they support the cortical bone along well defined paths of stress along well defined paths of stress and strain.and strain.


MYOTONIC APPLIANCEMYOTONIC APPLIANCE

Rely on muscle mass and resting Rely on muscle mass and resting pressurepressure

This was achieved by-This was achieved by-

1. increasing the interocclusal distance 1. increasing the interocclusal distance with the construction bitewith the construction bite

2. immobilizing the appliance ( eg adding 2. immobilizing the appliance ( eg adding clasp on lateral maxillary teeth- Herren )clasp on lateral maxillary teeth- Herren )

3. increase in dislocation of mandible in 3. increase in dislocation of mandible in vertical and saggital direction. vertical and saggital direction.


MYODYNAMIC MYODYNAMIC APPLIANCEAPPLIANCE

Make use of muscle activity and movement.Make use of muscle activity and movement.

1. H. P. Bimler - found the possibility of 1. H. P. Bimler - found the possibility of expanding the maxillary arch by crosswise expanding the maxillary arch by crosswise transmission of transverse mandible transmission of transverse mandible movements. movements.

2. features of elastischer gebissformer-2. features of elastischer gebissformer-

a. could be worn during the entire daya. could be worn during the entire day

b. elasticity help translate muscle b. elasticity help translate muscle movement movement

to dentition and supporting tissueto dentition and supporting tissue


CONTRACTILITY OF CONTRACTILITY OF MUSCLEMUSCLE

Classified into two types based on change Classified into two types based on change in the length of muscle fiber or tension of in the length of muscle fiber or tension of the muscle-the muscle-

1. Isotonic contraction- tension remains 1. Isotonic contraction- tension remains the same and change occurs in the length the same and change occurs in the length of muscle fiber. eg. Simple flexion of armof muscle fiber. eg. Simple flexion of arm

2. Isometric contraction- length of 2. Isometric contraction- length of muscle fiber remains the same and the muscle fiber remains the same and the tension is increased.tension is increased.

eg. Pulling any heavy objecteg. Pulling any heavy objectwww.indiandentalacademy.com

CLASSIFICATION CLASSIFICATION OF FUNCTIONAL OF FUNCTIONAL

APPLIANCESAPPLIANCES


1. a. Tooth borne passive appliance-1. a. Tooth borne passive appliance-

have no intrinsic force generating have no intrinsic force generating component such as spring or screw. component such as spring or screw. They depend on soft tissue stretch and They depend on soft tissue stretch and muscle activity to produce the desired muscle activity to produce the desired treatment results. treatment results.

eg. Activatoreg. Activator


b. Tooth borne active appliance- b. Tooth borne active appliance- include modification of activator and include modification of activator and

bionator that include expansion screw bionator that include expansion screw or other active components like or other active components like springs.springs.

c. Tissue borne passive appliance-c. Tissue borne passive appliance- located in the vestibule and have little located in the vestibule and have little

or no contact with the dentition.or no contact with the dentition. eg. Functional regulator of Frankeleg. Functional regulator of Frankel


2. a. Myotonic appliance2. a. Myotonic appliance

b. Myodynamic applianceb. Myodynamic appliance


4. Group 1 appliance-4. Group 1 appliance-

they transmit the muscle force directly to the they transmit the muscle force directly to the teeth for the purpose of correction of malocclusion.teeth for the purpose of correction of malocclusion.

eg. Oral screen and inclined planes ( oppenheim eg. Oral screen and inclined planes ( oppenheim splint)splint)

Group 2 appliance-Group 2 appliance-

they reposition the mandible and the resultant they reposition the mandible and the resultant force is transmitted to the teeth and other force is transmitted to the teeth and other structurestructure

eg. Activator and bionatoreg. Activator and bionator


Group 3 appliance-Group 3 appliance-

they also reposition the mandible, they also reposition the mandible, but the area of operation is the but the area of operation is the vestibule.vestibule.

eg. Frankel appliance and eg. Frankel appliance and vestibular screenvestibular screen


3. a. Removable functional appliance3. a. Removable functional appliance

b. Fixed functional applianceb. Fixed functional appliance


The bite is not opened beyond the The bite is not opened beyond the postural rest position. This stimulates postural rest position. This stimulates myotactic reflex activity causing myotactic reflex activity causing isometric contractions. This muscular isometric contractions. This muscular reflex is transmitted to the teeth through reflex is transmitted to the teeth through the appliance. Thus the appliance works the appliance. Thus the appliance works by making use of the kinetic energy.by making use of the kinetic energy.

This original concept and working This original concept and working hypothesis of Andresen and Haupl was hypothesis of Andresen and Haupl was accepted by many authorities but accepted by many authorities but rejected by some.rejected by some.


THE BITE OPENING THE BITE OPENING CONTROVERSYCONTROVERSY

By introducing a new path of closure, the By introducing a new path of closure, the activator causes musculoskeletal activator causes musculoskeletal adaptation. This adaptation process adaptation. This adaptation process caused by the activator also includes an caused by the activator also includes an effect on the condyle.effect on the condyle.

The condyle grow in an upward and The condyle grow in an upward and backward direction to maintain the backward direction to maintain the integrity of the TMJ structures. Such an integrity of the TMJ structures. Such an adaptation is caused by the loose fitting adaptation is caused by the loose fitting appliance. appliance.


Rolf Grude in 1952 gave an explanation Rolf Grude in 1952 gave an explanation for the continuing controversies. He for the continuing controversies. He said that the mode of action of activator said that the mode of action of activator as said by Andresen and Haupl can be as said by Andresen and Haupl can be seen only if the mandible is not seen only if the mandible is not displaced beyond the postural rest displaced beyond the postural rest position. If the mandible is opened position. If the mandible is opened beyond the rest position or the 4 mm beyond the rest position or the 4 mm limit the mode of action is quiet limit the mode of action is quiet different. different.


The appliance works by the viscoelastic The appliance works by the viscoelastic properties of the muscles or by properties of the muscles or by stretching of the soft tissues and not by stretching of the soft tissues and not by the Andresen and Haupl concept. the Andresen and Haupl concept. However since the interocclusal However since the interocclusal clearance varies from patient to clearance varies from patient to patient and also in the same individual patient and also in the same individual from time to time the statements of from time to time the statements of Grude are made with reservations.Grude are made with reservations.


1. Petrovic and McNamara support the 1. Petrovic and McNamara support the Andresen and Haupl concept and have Andresen and Haupl concept and have got results which indicate that a more got results which indicate that a more favorable condylar response to activator favorable condylar response to activator treatment may be possible if through treatment may be possible if through action of the appliance a proper action of the appliance a proper stimulus is provided. The stimulus from stimulus is provided. The stimulus from the appliance, muscle receptors and the the appliance, muscle receptors and the PD mechanoreceptors promote PD mechanoreceptors promote displacement of the mandible.displacement of the mandible.


Both Petrovic and McNamara have Both Petrovic and McNamara have shown the great imp. of lateral shown the great imp. of lateral pterygoid muscle for the forward growth pterygoid muscle for the forward growth of the mandible. An appliance which of the mandible. An appliance which holds the mandible rigidly in a forward holds the mandible rigidly in a forward direction doesn’t stimulate lateral direction doesn’t stimulate lateral pterygoid activity which in turn does not pterygoid activity which in turn does not stimulate condoyle growth. Based on stimulate condoyle growth. Based on this research Petrovic and McNamara this research Petrovic and McNamara support the view support the view


that variation in the mode and that variation in the mode and direction of dislocation of the mandible direction of dislocation of the mandible are decisive factors in activator Tt.are decisive factors in activator Tt.

2. A second group of authors ( Selmer-2. A second group of authors ( Selmer-Olsen, Herren, Harvold and Woodside) Olsen, Herren, Harvold and Woodside) do not support the theory of myotactic do not support the theory of myotactic reflex activity with isometric muscle reflex activity with isometric muscle contractions as stipulated by Andresen. contractions as stipulated by Andresen. Selmer-Olsen says that muscle activity Selmer-Olsen says that muscle activity cannot be stimulated at night because cannot be stimulated at night because


nature has designed them to rest during nature has designed them to rest during sleep. He says that, the mandible assumes sleep. He says that, the mandible assumes a position of equilibrium at night. An a position of equilibrium at night. An opening beyond this position requires opening beyond this position requires active work from the opening muscle to active work from the opening muscle to overcome the resistance of the stretched overcome the resistance of the stretched fibers in the soft tissues. If a foreign body fibers in the soft tissues. If a foreign body is inserted between the jaws keeping the is inserted between the jaws keeping the mandible beyond the equilibrium position, mandible beyond the equilibrium position, the closing muscles remain stretched. the closing muscles remain stretched.


A pressure is exerted against the foreign body A pressure is exerted against the foreign body through the teeth. Hence, the tooth moving through the teeth. Hence, the tooth moving forces in activator therapy are not due to forces in activator therapy are not due to muscle forces or kinetic energy but by a muscle forces or kinetic energy but by a stretching of soft tissues or potential energy.stretching of soft tissues or potential energy.

Woodside calls this viscoelastic property. Woodside calls this viscoelastic property. Herren analyzed the activators mode of action Herren analyzed the activators mode of action on the basis of the spatial relationship on the basis of the spatial relationship between the mandible and postural rest between the mandible and postural rest position. He states that the activator does not position. He states that the activator does not work in the way postulated by Andresen even work in the way postulated by Andresen even if the caudal displacement is less than 3 mm.if the caudal displacement is less than 3 mm.


Such an appliance does not increase frequency Such an appliance does not increase frequency of closing movements. Herren overextends in of closing movements. Herren overextends in the saggital direction bringing the mandible in the saggital direction bringing the mandible in anan

edge to edge incisal relationship. According to edge to edge incisal relationship. According to him, when an activator is inserted in the mouth, him, when an activator is inserted in the mouth, it restricts the mandible from assuming any it restricts the mandible from assuming any lateral protrusive or retrusive rest positions lateral protrusive or retrusive rest positions normally assumed during sleep. The forces normally assumed during sleep. The forces which pull the appliance towards these rest which pull the appliance towards these rest position are absorbed by the appliance and position are absorbed by the appliance and transmitted to the teeth and alveolar processes.transmitted to the teeth and alveolar processes.


These are the teeth moving forces. These are the teeth moving forces. According to Herren, mandible movements According to Herren, mandible movements do occur, but forces created thereby are of do occur, but forces created thereby are of minor importance.minor importance.

According to Harvold-Woodside the mandible According to Harvold-Woodside the mandible normally drops open when the patient is normally drops open when the patient is asleep.asleep.

Interocclusal clearance is more during sleep Interocclusal clearance is more during sleep and hence there is a chance that the and hence there is a chance that the appliance will not be retained in the mouth appliance will not be retained in the mouth and no skeletal or dental changes can be and no skeletal or dental changes can be expected.expected.


He states that high construction He states that high construction bites as much as 10-15 mm beyond bites as much as 10-15 mm beyond the postural rest position spreads the postural rest position spreads the jaws apart. The effect is a the jaws apart. The effect is a stretching of the elevators and stretching of the elevators and retractors of the mandible. The retractors of the mandible. The forces thereby created transmitted forces thereby created transmitted to the teeth and alveolar processes.to the teeth and alveolar processes.


3. Between the two extremes there are many 3. Between the two extremes there are many who take a higher construction bite without the who take a higher construction bite without the extreme sagittal extension advocated by Herren. extreme sagittal extension advocated by Herren. These authors include Schmuth, Witt and These authors include Schmuth, Witt and Komposch. Eschler says that if the bite is opened Komposch. Eschler says that if the bite is opened 4-6mm beyond postural rest position, the 4-6mm beyond postural rest position, the appliance works alternately with isometric and appliance works alternately with isometric and isotonic muscle contraction. At insertion of the isotonic muscle contraction. At insertion of the appliance, isotonic muscle contraction cause appliance, isotonic muscle contraction cause elevation of the mandible. When the mandible elevation of the mandible. When the mandible contacts the appliance isometric contraction contacts the appliance isometric contraction begins. begins.


The elevators remain stretched as the The elevators remain stretched as the mandible cannot assume its rest position. As mandible cannot assume its rest position. As they fatigue the contraction cease and the they fatigue the contraction cease and the mandible drops down. After recovery, the mandible drops down. After recovery, the same cycle is repeated.same cycle is repeated.

In conclusion, there are two main theories In conclusion, there are two main theories regarding the activators mode of action. regarding the activators mode of action. According to the first, loose appliance According to the first, loose appliance stimulates the muscle and it is the activator in stimulates the muscle and it is the activator in motion that moves the teeth. The forces are motion that moves the teeth. The forces are intermittent in nature hitting the teeth as intermittent in nature hitting the teeth as jolts. The elevator of mandible and other units jolts. The elevator of mandible and other units of orofacial complex have to do active work in of orofacial complex have to do active work in order to keep the activator in place. order to keep the activator in place.


It is a prerequisite for such a mode of action It is a prerequisite for such a mode of action that the mandible is not displaced beyond that the mandible is not displaced beyond the postural rest position.the postural rest position.

The other hypothesis says that it is the The other hypothesis says that it is the activator at rest which moves the teeth. The activator at rest which moves the teeth. The appliance is squeezed between the jaws. In appliance is squeezed between the jaws. In such a position it exerts a continuous such a position it exerts a continuous pressure against teeth. However the force pressure against teeth. However the force application is interrupted every time the application is interrupted every time the activator is removed from the mouth.activator is removed from the mouth.


The periodicity thereby introduced is The periodicity thereby introduced is called called

‘ ‘ big intermittence’. When the big intermittence’. When the appliance is in the mouth force appliance is in the mouth force application may be interrupted for a application may be interrupted for a single tooth or a group of teeth. This single tooth or a group of teeth. This periodicity is called the ‘little periodicity is called the ‘little intermittence’intermittence’


CONSTRUCTION BITECONSTRUCTION BITE

The positioning of the mandible in The positioning of the mandible in preparation for the fabrication of preparation for the fabrication of functional appliance is considered in functional appliance is considered in three planes of space-three planes of space-

verticalvertical

horizontalhorizontal

transversetransverse


The vertical opening of the mandible The vertical opening of the mandible depends on the following things-depends on the following things-

1. the kind of dysgnathic or dysplastic 1. the kind of dysgnathic or dysplastic problem ( sagittal or vertical problem ( sagittal or vertical relationship)relationship)

2. the developmental state, age and 2. the developmental state, age and sex of patientsex of patient

(potential incremental changes)(potential incremental changes)

3. the type of activator to be used3. the type of activator to be usedwww.indiandentalacademy.com

Different sagittal and vertical dysplasia Different sagittal and vertical dysplasia require different construction bite require different construction bite registration.registration.

1. Deep bite Class II Div 2 malocclusion1. Deep bite Class II Div 2 malocclusion

2. Class III malocclusion2. Class III malocclusion

It is necessary to record the vertical It is necessary to record the vertical distance between the incisal margins of distance between the incisal margins of upper and lower incisor edges when upper and lower incisor edges when determining how wide the construction determining how wide the construction bite should be.bite should be.


Class II Div 2 and Class III- 1.5- 3 mmClass II Div 2 and Class III- 1.5- 3 mm Mixed Dentition- 4 – 7mmMixed Dentition- 4 – 7mm Severe Class II Div 2 – upto 9mmSevere Class II Div 2 – upto 9mm 1. Woodside philosophy1. Woodside philosophy 2. brings the mandible out of the range 2. brings the mandible out of the range

of any tooth guidance and the resultant of any tooth guidance and the resultant retrusive effect on the condyle and the path retrusive effect on the condyle and the path of closureof closure

3. horizontal growth pattern/ forward 3. horizontal growth pattern/ forward and upward rotating pattern- deepening of and upward rotating pattern- deepening of bite bite


In a full Class II Div 1 malocclusion In a full Class II Div 1 malocclusion with a protrusion of upper incisor with a protrusion of upper incisor and deep overbite, the opening of and deep overbite, the opening of bite is dependant on how much bite is dependant on how much anterior posturing is necessary to anterior posturing is necessary to establish a normal sagittal establish a normal sagittal relationship.relationship.

1.1. If lessIf less

2.2. If significantIf significantwww.indiandentalacademy.com

Class II Div 1 malocclusion in whichClass II Div 1 malocclusion in which

1. sagittal malrelation is the width of 1. sagittal malrelation is the width of a premolara premolar

2. severe curve of Spee2. severe curve of Spee

3. lower incisors are over erupted and 3. lower incisors are over erupted and impinge on the palatal mucosa impinge on the palatal mucosa

Construction bite should not be higher Construction bite should not be higher than the vertical edge to edge incisor than the vertical edge to edge incisor relationship.relationship.


Considerations for horizontal posturing of the Considerations for horizontal posturing of the mandible-mandible-

1.1. Original sagittal jaw relationship may be maintained, Original sagittal jaw relationship may be maintained, as in neutroclusion with a class II type of incisor as in neutroclusion with a class II type of incisor overjet and deep bite or in a similar Class II overjet and deep bite or in a similar Class II relationship due to maxillary protractionrelationship due to maxillary protraction

2.2. The mandible may be postured forward to change the The mandible may be postured forward to change the sagittal relationship equally on both sides when the sagittal relationship equally on both sides when the problem is a bilaterally symmetrical Class II problem is a bilaterally symmetrical Class II condition.condition.

3.3. The bite is changed on one side but is maintained as The bite is changed on one side but is maintained as much as possible on the other side- unilateral case much as possible on the other side- unilateral case

4.4. The mandible is postured backward as much as The mandible is postured backward as much as possible in the fossa, opening the bite enough to try possible in the fossa, opening the bite enough to try for an end to end incisal relationship as in Class III for an end to end incisal relationship as in Class III malocclusion. malocclusion.


Conditions in which mandible is not postured Conditions in which mandible is not postured forward while constructing the bite-forward while constructing the bite-

1. Class II malocclusion due to mesial 1. Class II malocclusion due to mesial positioning of the maxilla itself or of the positioning of the maxilla itself or of the dental arches, pulled forward by a prolonged dental arches, pulled forward by a prolonged finger sucking habit.( extract)finger sucking habit.( extract)

2. Class I with cross bite of individual or all 2. Class I with cross bite of individual or all incisors.( downward and backward)incisors.( downward and backward)

3. Class II malocclusion in which there is 3. Class II malocclusion in which there is mesial positioning or displacement from mesial positioning or displacement from postural rest to occlusion. Mandible closes postural rest to occlusion. Mandible closes upward and excessively forward under tooth upward and excessively forward under tooth guidence, instead of being functionally guidence, instead of being functionally retruded ( bimax) retruded ( bimax)


Degree of mandible Degree of mandible advancement-advancement-

Newmann – advances mandible to a Newmann – advances mandible to a width of an entire toothwidth of an entire tooth

Frankel – stepwise advancementFrankel – stepwise advancement Eschler – greatest possible Eschler – greatest possible

advancement with which the patient advancement with which the patient can be comfortable.can be comfortable.


CONSTRUCTION BITE CONSTRUCTION BITE REGISTRATIONREGISTRATION

In miixed dentition it is sometimes In miixed dentition it is sometimes difficult to determine precisely how difficult to determine precisely how much the mandible has been moved much the mandible has been moved forward in the construction bite forward in the construction bite because of the wax roll covering the because of the wax roll covering the tooth contact surface-tooth contact surface-

use deciduous canine/upper first use deciduous canine/upper first premolar as a guidepremolar as a guide


MIDLINE MIDLINE CONSIDERATIONSCONSIDERATIONS

If the upper and lower midline are If the upper and lower midline are coincident in the habitual occlusion and coincident in the habitual occlusion and the sagittal relationship is bilaterally the sagittal relationship is bilaterally symmetrical then the midlines should symmetrical then the midlines should line up in forward posturing in the same line up in forward posturing in the same relationship as in habitual occlusion. For relationship as in habitual occlusion. For this was is cut away in the midline to this was is cut away in the midline to make sure that the posturing forward make sure that the posturing forward has not allowed the mandible to deviate has not allowed the mandible to deviate to one side or the other. to one side or the other.


If the upper and lower midlines do If the upper and lower midlines do not coincide-not coincide-

premature loss of deciduous caninepremature loss of deciduous canine

occlusal interference occlusal interference

Construction bite should follow the Construction bite should follow the midlines of the maxilla and midlines of the maxilla and mandible, regardless of the shifting mandible, regardless of the shifting of teeth in one jaw or the other. of teeth in one jaw or the other.


CONSTRUCTION BITE CONSTRUCTION BITE TECHNIQUETECHNIQUE

Patient compliance is essentialPatient compliance is essential this can be achieved by asking the pt to this can be achieved by asking the pt to

advance the mandible in case of Class II advance the mandible in case of Class II malocclusion to create an instant malocclusion to create an instant correction. The pt sees the potential and correction. The pt sees the potential and objectives of the correction to be objectives of the correction to be brought about by the functional brought about by the functional appliance and is more likely to work appliance and is more likely to work towards this goal of esthetic towards this goal of esthetic improvement as compared to dental improvement as compared to dental health and functional improvement. health and functional improvement.


1. STUDY MODEL ANALYSIS1. STUDY MODEL ANALYSIS

a. the first molar relationship in habitual a. the first molar relationship in habitual occlusion is determinedocclusion is determined

b. nature of midline discrepancy if any is b. nature of midline discrepancy if any is determineddetermined

c. symmetry of dental arches is determined- c. symmetry of dental arches is determined- asymmetry such as segmental open bite can asymmetry such as segmental open bite can be corrected with an activatorbe corrected with an activator

d. the curve of Spee is checked to see if can d. the curve of Spee is checked to see if can or should be leveled with the appliance. or should be leveled with the appliance.


2. FUNCTIONAL ANALYSIS2. FUNCTIONAL ANALYSIS

a.a. Precise registration of the ret position is Precise registration of the ret position is made as the vertical opening of the made as the vertical opening of the construction bite depends on thisconstruction bite depends on this

b.b. Path of closure from postural rest to Path of closure from postural rest to habitual occlusion is analyzed.habitual occlusion is analyzed.

c.c. Prematurities, occlusal interferences and Prematurities, occlusal interferences and mandibular displacement if any are mandibular displacement if any are checkedchecked


d. Interoccluasal clearance is checked d. Interoccluasal clearance is checked several times and the mean amount several times and the mean amount is recordedis recorded

e. TMJ should be palpated for clicking, e. TMJ should be palpated for clicking, crepitus ect. Which may lead to crepitus ect. Which may lead to modification in the appliancemodification in the appliance

f. Respiration assesmentf. Respiration assesmentwww.indiandentalacademy.com

3. CEPHALOMETRIC ANALYSIS3. CEPHALOMETRIC ANALYSIS a. direction of growth- average, horizontal a. direction of growth- average, horizontal

or vertical is determinedor vertical is determined b. the difference between the position and b. the difference between the position and

the size of the jaw bases is determinedthe size of the jaw bases is determined c. the axial inclination and the position of c. the axial inclination and the position of

maxillary and mandibular incisors are maxillary and mandibular incisors are determined. This provides imp. diagnostic determined. This provides imp. diagnostic and prognostic clues for determining the and prognostic clues for determining the anterior positioning of the mandible and the anterior positioning of the mandible and the appliance design detail for the incisor area.appliance design detail for the incisor area.


CONSTRUCTION BITE CONSTRUCTION BITE PLANNINGPLANNING

On the basis of inf. gathered the On the basis of inf. gathered the extent of ant. positioning for Class II extent of ant. positioning for Class II malocclusions and post. positioning malocclusions and post. positioning for Class III malocclusions is for Class III malocclusions is determined.determined.


Ant. positioning of this magnitude is Ant. positioning of this magnitude is contraindicated in-contraindicated in-

a.a. If the overjet is too large( 18 mm), then If the overjet is too large( 18 mm), then anterior positioning is a stepwise anterior positioning is a stepwise progression accompanied in two or three progression accompanied in two or three phases.phases.

b.b. If there is severe labial tipping of maxillary If there is severe labial tipping of maxillary incisors, they should be uprighted first, if incisors, they should be uprighted first, if possible, by a prefunctional appliance.possible, by a prefunctional appliance.

c.c. Pathological construction bite in case of in Pathological construction bite in case of in case of palatal eruption of incisor. case of palatal eruption of incisor.


Principles in maintaining a proper Principles in maintaining a proper horizontal- vertical relationship and horizontal- vertical relationship and determining the height of the bite-determining the height of the bite-

a.a. The mandible must be dislocated The mandible must be dislocated from the rest position in atleast one from the rest position in atleast one direction. This is essential in order to direction. This is essential in order to activate the associated musculature activate the associated musculature and induce strain in tissue.and induce strain in tissue.

b.b. Inverse relation between forward Inverse relation between forward positioning and vertical opening.positioning and vertical opening.


Execution of construction Execution of construction bite techniquebite technique



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Wolff’s law

Health & Medicine

Transcript of Wolff’s law