WO2020144569A1

WO2020144569A1 - Method for individual dental design

Info

Publication number: WO2020144569A1
Application number: PCT/IB2020/050082
Authority: WO
Inventors: Giovanni Maver
Original assignee: Giovanni Maver
Priority date: 2019-01-10
Filing date: 2020-01-07
Publication date: 2020-07-16
Also published as: IT201900000328A1

Abstract

Method for individual dental design of a patient comprising the following steps: classifying said patient; determining the occlusal plane and the intermaxillary relationship of said patient; spatially positioning the dental arches of said patient by means of cranial of facial scans; in the case of cranial scan an average is calculated in the three planes of space between the skeletal landmarks; in the case of facial scan an average is calculated in the three planes of space of the cutaneous landmarks; selecting the bio-volumetric templates and the dental libraries suitable for said patient; calibrating said bio-volumetric templates and the dental libraries; positioning said bio-volumetric templates and the dental libraries; designing the dental arches of said patient in relation to what was determined previously; said step of determining the occlusal plane and the intermaxillary relation during swallowing of said patient comprises the steps of: using the aesthetic line, which is the line tangent to the bipupil line and parallel to the 6 lower front teeth; using the Frankfort plane; using the Camper's plane; said step of designing the dental arches of said patient comprises the steps of using an integrated basic dental library; said integrated basic dental library defines the teeth positioned in the space classified based on the bio- volumetric templates, on the biotype, on the shape of the teeth, on the shape of the lips, on the shape of the nose and on the shape of the cranium; said bio-volumetric templates are determined based on the biotype to which said patient belongs and identifying the inclination of the Von Spee and Wilson curves; said dental libraries comprise information in relation to the biotype, to the shape of the teeth, to the shape of the lips, to the shape of the nose and to the shape of the cranium.

Description

METHOD FOR INDIVIDUAL DENTAL DESIGN

DESCRIPTION

The present invention relates to a method for individual dental design.

This method can be used integrated in a software program, in analog mode or partially analog and partially digital mode.

The priority in the human system in physiology, i.e., in the absence of pain, is the search for balance, as by doing so it makes minimum use of the muscle structure. Balance that is not static but dynamic; in fact, even when we are convinced we are not moving, our heart is beating, we are breathing and when we are standing still to counter gravity, we activate the muscle structure, constantly maintaining a slight anteroposterior oscillation by means of small lateral adjustments.

The cardinal points of the body, in physiology, are aligned along an imaginary line perpendicular to the floor. However, we all know that there are differences between the two sides of the body linked to muscular facilitation (right- or left- handedness).

Differences that determine compensations with adaptive torsions in the three planes of space, for example, the more the shoulders twist from right to left, the more the pelvis twists from left to right, the two torsions nullify each other and we thus maintain the balance of the cardinal points with slight asymmetries between the shoulders and pelvis. Therefore, each body has its own asymmetric physiological, constantly searching in movement for a biosymmetry of function.

If the body is asymmetrical, it is logical to think that the dental arches are also asymmetrical. Therefore, in line with the aim of the body in physiology, in prosthetic restoration it is top priority to seek the balance of the stomatognathic system, respecting the structural asymmetry of each individual. Everybody is unique in its shape and function, and each individual has a postural harmony.

The origin of asymmetries is influenced by the spatial relation that is determined between the occipital bone and the sphenoid bone at the level of the Sphenoid Basilar Synchondrosis (SBS). Due to the central position that these two bones occupy, they have a three-dimensional influence on all the bones of the cranium establishing harmonies with the differences between the two sides of the face. The sphenoid bone influences the position of the bones of the upper part, hence eye line and maxillary, the occipital bone influences the position of the bones of the lower part, hence mandible and smile line. The occipital bone influences, with its position, also the first cervical vertebrae (AEO) and consequently the whole of the spinal column, hence influencing the rest of the skeleton and the muscles.

As long as the harmonies find adaptive compensations, maintaining balance and preserving function without pain this is physiology; then, when a problem causes compensation that triggers painful symptoms and obliges us to make adaptive compensations with functional limits to the detriment of balance, we move progressively towards pathology, until we reach functional blockages.

As part of the body, the mouth functions with rules that are common thereto, and therefore a multi-disciplinary approach should be used, starting from an assessment of the whole body to achieve a correct interpretation of the stomatognathic system.

The object of the present invention is to provide a method for individual dental design.

Another object is to provide a method capable of reproducing an individual and balanced smile for each individual patient, in harmony with the face and the rest of the body.

In accordance with the present invention, these purposes and others yet are achieved by a method for individual dental design in accordance with the appended claims.

The advantages of this solution with respect to the prior art solutions are various.

The construction of integrated basic dental libraries makes it possible to create, in a rapid, simple and efficient manner, in relation to the information observed on the patient with the assessment sheet, a customised basic prosthetic rehabilitation project, in relation to:

Dental arch-volume shape biotype.

Shape of lip dominance of the sextant front teeth on the Y coordinate.

Shape of nose dominance of the 4 front teeth on the Z coordinate.

Shape of cranium dental positions on the ZXY coordinates.

The creation of position algorithms of the teeth in the basic and integrated dental libraries allows the rapid implementation, by means of the acquisition of other natural teeth or artificial commercial teeth, of further dental libraries along the lines of those already existing.

The possibility of partially or totally varying the position of the teeth due to the position algorithms allows, with the acquisition of physiological natural mouths, in Torsion or in Lateral Flexion Rotation, to have different degrees of adaptive compensations, the structuring of new dental libraries, recalculating the degrees in relation to the cranial harmonies.

The possibility of varying the spatial relation between the upper and lower bio- volumetric template combined with the possibility of varying the dental position algorithms allows, with the acquisition of natural mouths of dental class 2 or 3, to have different degrees of volumetric redistributions between upper and lower dental arches, the structuring of new dental libraries, recalculating the degrees in relation to the dental class.

The characteristics and the advantages of the present invention will become clearer from the following detailed description of a practical embodiment thereof, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Fig. 1 schematically shows the Marcel Martiny classification that defines the biotype as Endoblast, Mesoblast, Cordoblast, Ectoblast;

Fig. 2 schematically shows the osteopathic classification in succession from left to right as left lateral flexion rotation sx, left torsion sx, right lateral flexion rotation dx, right torsion dx;

Fig. 3 schematically shows the dental cardinal points, raphe and compensatory curves of a left torsion sx and of a right lateral flexion rotation dx;

Fig. 4 schematically shows the Claude R. Rufenacht classification in the dominances from 1 to 4;

Fig. 5 schematically shows the Gerber classification;

Fig. 6 schematically shows the Frankfort plane and the Camper’s plane;

Fig. 7 schematically shows the bio-volumetric templates;

Fig. 8 schematically shows the shape of the teeth in relation to the biotype, from left to right of the sagittal plane, frontal and incisal, from bottom to the top ectoblast, cordoblast, mesoblast, endoblast;

Fig. 9 schematically shows the positioning of the bio-volumetric templates;

Fig. 10 schematically shows the positioning of the bio-volumetric templates based on the landmarks; Fig. 1 1 schematically shows an example of dental design;

Fig. 12 schematically shows an example of the axes of the main components of an object.

The procedure for individual dental design comprises the following seven steps.

1. Classification of the patient.

2. Determination of the occlusal plane and of the initial intermaxillary relationship.

3. Spatial positioning of the dental arches.

4. Choice of the Bio-volumetric Templates and of the dental libraries.

5. Calibration of the Bio-volumetric Template and of the integrated basic Dental library, in relation to the patient.

6. Positioning of the Bio-volumetric templates and of the dental libraries.

7. Individual design.

The first step comprises classification of the patient, by means of some methods, filling in the assessment sheet named AEP® System.

One method is the Marcel Martiny classification, which determines the biotype of the patient from the following: Endoblast, Mesoblast, Cordoblast, Ectoblast, which influences the shapes and the volumes of bodies, faces, dental arches and teeth.

Another methodology is the osteopathic classification, which provides indications on the shape of the cranium in relation to the harmonies of the face (left or right torsion and right or left lateral flexion rotation), influencing the cranial volumes and consequently the dental arches and the position of the teeth.

Another methodology is the Claude R. Rufenacht classification, which defines the type of lips which with their shape express the dominance of the front dental sector. Another methodology is the Gerber classification, which by means of the relationship between the base and its wings, the nose, is an expression of the relationship in vertical direction between central/lateral incisors.

The second step comprises the determination of the occlusal plane and of the initial intermaxillary relationship.

To assess the occlusal plane the aesthetic line is used; this is the line tangent to the bipupil line and parallel to the 6 lower front teeth; the Frankfort plane, which is the plane that passes through the two porion (Po) and the two inferior margins of the orbits (Or); the Camper’s plane, which is the plane that passes through the centre of the external ear canal and the anterior nasal spine (Ans).

The two planes are convergent behind the auditory meatuses and open at the front with an angle that varies between 1 1 ° and 15°.

In the literature, the Camper’s plane is considered parallel to the occlusal plane (meant as ideal plane on which the maxillary vestibular cusps rest up to the sixth tooth) from which it is spaced by about 35 mm, but in actual fact there is no plane on which the teeth rest in an equidistant and symmetrical manner. Instead, there is an occlusal reference plane that, just as any other plane, requires three points in order to be determined.

The first permanent teeth to erupt at 6 years of age are the upper first molars and the lower incisors and therefore in order to represent the reference plane we use, at the back, the two mesiolingual cusps of the upper first molars and, as front reference, the average between the highest points of the two mesial incisal margins of the two lower central incisors. The other teeth will erupt subsequently and be arranged in relation to the postural harmonies.

Therefore, the occlusal reference plane consists at the front of the point in which the Frankfort plane intercepts the average between the highest points of the two mesial margins of the lower central incisors and at the back of the point in which the Camper’s plane intercepts the two mesiolingual cusps of the upper first molars. This ideal plane in physiology is tendentially parallel to the floor.

If the intermaxillary relationship is physiological, the occlusal reference plane will be detected by using the dental landmarks described above. If the landmarks are not present or due to alterations of the physiological intermaxillary relationship, AEP® System mastication plates or intermaxillary alignment plates will be constructed and adjusted with consequent detection of the intermaxillary relationship during swallowing.

The third step comprises the spatial positioning of the dental arches that can be associated with cranial or facial scans.

The cranial or facial scan is used to position the head.

In the case of cranial scan, an average is calculated in the three planes of space between the skeletal landmarks that are least influenced by the intrinsic cranial asymmetry, hence the following are used:

• on the frontal plane (Z coordinate at 0°), the line tangent to the highest point of the crista galli, the anterior nasal spine and the centre of the mental protuberance,

• on the sagittal plane (Y coordinate at 0°), the line tangent to the highest point of the crista galli, the palatine raphe and geometrical centre of the sella turcica,

• on the horizontal plane (X coordinate at 0°), the two inferior margins of the orbits and the porion of both sides.

In the case of facial scan an average is calculated in the three planes of space of the cutaneous landmarks that are least influenced by the inherent facial asymmetry, hence the following are used: • on the frontal plane (Z coordinate at 0°), the line tangent to the centre of the glabella, centre of the base of the nose and centre of the mental protuberance,

• on the sagittal plane (Y coordinate at 0°), the line tangent to the centre of the glabella and the median line of the head,

The dental arches are positioned in relation to the head using a marker with specific mathematics, present both in the cranial or facial scans and in the scans of the working models. The marker is used to be able to initially couple the upper model with the scans of the head and subsequently, through the intermaxillary relationship detected in the mouth or the maximum intercuspation, the lower model is positioned. After obtaining the correct positioning of the upper and lower master models, through fine coupling other upper and lower models with different situations can be coupled, such as: abutment model, temporary model, etc.

The system implemented to align the imported teeth with those of the library is the following:

• The axis of the main component of the "target" tooth, i.e., the one of the libraries, is identified.

• The 3 axes of the main components of the "input" tooth, i.e., the one imported and which must be aligned with the "target" tooth of the library, is identified.

For each of the 3 axes of the "input" tooth:

° The rototranslation required to align the axis of the "input" tooth with that of the "target" tooth is calculated.

° The rototranslation is applied and in this situation registration of the mesh using the existing basic or integrated libraries is carried out. ° The error made with this particular rototranslation (the one to unify the two axes + the one deriving from the existing basic or integrated libraries) is calculated and the best is kept.

° The same procedure is also carried out with the main axis of the "input" tooth inverted and with the object rotated by 180° with respect to the axis and once again the best is kept; therefore 4 possible alignments of the axes must be tested for each axis.

• The best rototranslation calculated is applied.

Axis of the main component of a mesh means the axis along which the dispersion of the vertices of the mesh is maximum, which indicates a possible orientation of the object, as these are three-dimensional objects three components, i.e., three axes, each with its degree of dispersion, can be identified.

In order to obtain the best possible alignment, the algorithm of registration of the existing basic or integrated meshes is carried out after the axes of the two meshes to be registered have been aligned; this procedure is repeated on all three possible axes and for each of the axes it is repeated both with the axis inverted and with the object rotated through 180° with respect to the axis.

For each alignment, the error made is calculated and the one with the minimum error is kept.

The image of Fig. 12 shows what is meant by axes of the main components of an object; imagine that the points in the figure represent the vertices of the mesh that defines the object, the axis of the main component can be seen in the 1 st axis, the other two axes can be seen in the 2nd axis and in the 3rd axis.

To position the dental arches alone, the working models and the bio- volumetric templates are used as follows. If the intermaxillary relationship and the dental landmarks are physiological, the dental landmarks present are used.

If the intermaxillary relationships or the dental landmarks are not physiological, the AEP® System intermaxillary register plates, from which the occlusal reference plane is deduced, are designed, constructed and functionalised on the patient.

The upper and lower models in maximum intercuspation or with the intermaxillary register plates inserted (aided, if possible, by photographs of the head of the patient in frontal and sagittal projection), are used calculating the average:

• on the sagittal plane (Y coordinate at 0°), the palatine raphe of the upper model is centred,

• on the frontal plane (Z coordinate at 0°), the front reference represented by the lower central incisors is centred,

• on the horizontal plane (X coordinate at 0°), the rear reference represented by the upper first molars is centred.

Subsequently, through fine coupling, other upper and lower models with different situations can then be coupled, such as: abutment model, temporary model, etc.

The fourth step comprises the use of information of the assessment sheet for the construction/selection of the integrated basic dental library and selection of the Bio-volumetric templates.

For construction/selection of the bio-volumetric templates and dental libraries the biotype to which said patient belongs is determined in relation to the four biotypes of the Martiny embryogenetic classification and the inclination of the Von Spee and

Wilson curves are identified.

The bio-volumetric templates are a tool with symmetrical references used for: • determining the shape of the arches in relation to the biotype, positioning the vestibular cusps on the arches;

• setting a relationship of balance of dental class 1 , positioning the cardinal dental points along the lines of growth.

For further information concerning the Bio-volumetric templates and basic dental libraries reference should be made to the description of the Italian patent no. 0001397464.

The teeth in the basic dental libraries, better defined below, are positioned in space with a criterion of symmetry in relation to the Bio-volumetric templates:

• maintaining a trend in relation to the biotype with the vestibular cusps of the upper teeth aligned on the outer arch of the upper flat template and the vestibular cusps of the lower teeth aligned on the inner arch of the lower cup template,

• maintaining a trend in relation to the Camper’s plane with all the vestibular cusps of the upper teeth up to the sixth tooth (except for the incisal margin of the lateral incisors and the mesio-vestibular cusps of the sixth teeth detached by 1 mm) and all the lingual cusps of the upper back teeth up to the sixth tooth (except for the lingual cusp of the fourth teeth and the disto-lingual cusps of the sixth teeth detached by 1 mm), resting on the upper flat template,

• maintaining the lower front group with an inclination in relation to the biotype of: 9° the endoblast, 10° the mesoblast, 1 1 ° the cordoblast; 12° the ectoblast,

• maintaining the seventh teeth if used with the vestibular and lingual cusps of the teeth detached by 1 mm from the upper flat template.

The interoccusal relationship between upper and lower teeth is then optimised using the relationship present in the literature tooth-to-two-teeth.

The fifth step comprises calibration of the Bio-volumetric template and of the dental libraries coupled with one another.

The dimensions of a flat template and of a cup template are determined based on the information obtained in the preceding steps based on the size of the teeth.

If even just one tooth is present, using Wheeler’s statistical model, with the proportional relationship created by him it is possible to calculate the measurements of the missing teeth.

In the case of total edentulism, a statistical rule present in the literature is applied, which states that the distance between the tips of the palatine rugae plus 4 mm, is equal to the sum of the mesiodistal diameters of the four upper front incisors and the crown length of the upper central incisor is equal to the distance between inter-incisal papilla and the fovea divided by 4; from these measurements with the Russell C. Wheeler’s proportional relationship, the measurements of the other teeth are obtained.

The sixth step comprises positioning of the bio-volumetric templates and of the dental libraries.

The Bio-volumetric templates and the dental libraries are then positioned by using the maxillary and mandible bone/muscle landmarks and the Occlusal reference plane.

In the maxillary the landmarks are: for the sagittal plane (Y coordinate), the raphe aligned with the growth vector Y1 , for the horizontal plane (X coordinate), the average resulting between the three landmarks expression of the position of the 1^st upper molar, such as, the point of maximum depth of the raphe V , the centre of the zygomatic incisure Z, the tip of the mesio-vestibular cusp W, or, if the tooth is missing, the centre of the depression located outside the crest (always present after its extraction), aligned with the growth vector X1. In the mandible the landmarks are: for the sagittal plane (Y coordinate), the central vestibular frenum 1 , the central lingual frenum 1 a, and the position of the raphe given by the upper 4, aligned with the growth vector Y1 ; for the horizontal plane (X coordinate), the average resulting between three landmarks expression of the position of the 1^st mandibular premolar, such as the lateral vestibular frenula 2-3 and lateral lingual frenula 2a-3a, the tip of the vestibular cusp 5, aligned with the growth vectors HY1 and XY2; in the absence of said landmarks both for the maxillary and for the mandible, others can be added due to normal experience, provided that they are an expression of the position of the dental cardinal points.

In the case of dental class 1 relationship, the following is obtained.

The bio-volumetric templates and the integrated basic dental libraries are structured to determine in their entirety a physiological relationship of dental class 1 ; therefore, if the patient has a class 1 intermaxillary relationship, they will only be positioned in relation to the occlusal reference plane and the result is that, by default, the upper flat template is tendentially parallel to the Camper’s plane and the lower cup template is tendentially parallel to the Frankfort plane.

In the case of dental class 2 division 1 relationship, the following is obtained.

The overall volume remains unchanged, but it is redistributed in the three planes of space. The reference always remains the occlusal reference plane, which in physiology will always be tendentially parallel to the floor.

Initially, a step of pivoting is carried out on the cardinal point corresponding to the mesio-lingual cusps of the upper molars and rotating the upper flat template clockwise, followed by pivoting on the cardinal point corresponding to the average between the two lower central incisors and rotating the lower cup template counter clockwise (central incisor teeth on the 3s). The degree of the rotations and of the modifications to be made to the volumes of the dental arches, will be in relation to the degree of class 2. The most evident three-dimensional volumetric adaptation is the reduction of the volume in anteroposterior direction of the lower dental arch (backward movement of a cusp in the molar relationship) and in the increase in the volume in anteroposterior direction of the upper dental arch (forward movement of the anterior dental group).

In the case of class 3 relationship, the following is obtained.

Initially, a step of pivoting is carried out on the cardinal point corresponding to the mesio-lingual cusps of the maxillary molars and rotating the upper flat template counter-clockwise, followed by pivoting on the cardinal point corresponding to the average between the two lower central incisors and rotating the lower cup template clockwise (central incisors on the 3s). The degree of the rotations and of the modifications to be made to the volumes of the dental arches will be in relation to the degree of class 3. The most evident three-dimensional volumetric adaptation is the increase of the volume in anteroposterior direction of the lower dental arch (forward movement of a cusp in the molar relationship) and the decrease in the volume in anteroposterior direction of the upper dental arch (backward movement of the anterior dental group).

The seventh step comprises individual design based on the preceding operations.

The structuring of integrated basic dental libraries makes it possible to create, in a rapid, simple and efficient manner, in relation to the information observed on the patient, a customised basic prosthetic restoration project, which is then individualised, in mutual continuity with the alveolar processes.

To optimise fine integration, the CAD manipulator is used, adapting the dental positions, harmonising them in continuity with the alveolar processes and leading to the attainment of an occlusal relationship suitable for the single case treated.

The project can be produced with different materials (resin, zirconia or the like) and with different aims (an aesthetic-functional try-in, a therapeutic temporary restoration, a permanent prosthesis, an orthodontic project or the like).

Restoration should take place through progressive recovery of the intermaxillary relationship (R.P.R.I). This is because in pathology, over time, the muscles structure an adaptive muscle engram; removing the pathological information the situation immediately improves, but time is required for the muscles to destructure the old pathological engram in order to restructure a new physiological one.

Therefore, the restoration to be carried out preferably has three steps.

A first step in which the system is reset, removing the information that obliges it to function pathologically (AEP® System reset plate, AEP® System intermaxillary relationship plate AEP® or others with the same aim).

A second step in which the system is tested, entering the information that allows it to function temporarily in physiological mode (AEP® System reprogramming bite, therapeutic temporary restoration or the like with the same aim).

A third step in which the system is fixed, stabilising the information that allows it to definitively function in physiological mode (restoration in composite resin, in zirconia, Toronto bars or the like with the same aim).

The work method can be developed in analog or digital mode. Integrated in software thanks to the automation of numerous operating steps that facilitate and simplify its use.

The integrated basic dental libraries are a database structured as follows.

The reference parameters of the assessment sheet, integrated with studies on the volumes of the teeth deriving from the observation of natural mouths, have allowed further parameters to be coded to structure the integrated basic dental libraries.

The biotype is defined. The Martiny classification is based on classification of the population in relation to biotypes, which involves, an arrangement of body volumes with the characteristics defined in space.

Endoblast biotype, short in height and stocky tending towards obesity and with a tendency to have short limbs in relation to the torso and poor muscle development.

Mesoblast biotype, average height, well-proportioned with well-developed muscles.

Cordoblast biotype, tall and slim, relatively well-proportioned with well- developed muscles.

Ectoblast biotype, tall and skinny with the tendency to have long limbs in relation to the torso and poor muscle development.

The distribution of the body volumes maintains this logic in the single body regions, thereby volumetrically influencing face shape - dental arch shape - teeth shapes.

The law of volumes is founded on the fact that once the volume has been determined, its quantity remains unchanged but is redistributed in relation to the three-dimensional actions that are applied thereto.

The three-dimensional actions influenced by the biotype act on the volume of the dental arches and on the dental volumes influencing them in the three planes of space with specific characteristics.

The shape of the teeth is defined.

The references for assessing them are the sagittal plane: heights of the contact points, heights of the vestibular and lingual equators, inclination of vestibular surface in 1 ^st cervical - 2^nd middle - 3^rd incisal.

The frontal plane: heights of contact points, heights of vestibular equators, inclination of transition lines.

The incisal plane: incisal margin trend, relationship of position between the vestibular and lingual transition lines.

The use of this information allows, if working in analog mode, the design and construction in the three planes of space of the relationship of position between the teeth in the dental arches and the volumetric arrangement of the single teeth, in relation to the biotype of the patient. If working in assisted software mode, it allows positioning of the natural and commercial artificial teeth on the XYZ coordinates and the definition of a volumetric criterion with which to select the teeth, in relation to the biotype, thus structuring the dental libraries from which to choose for designing in relation to the patient to undergo restoration.

The shape of the lips is defined.

The Rufenacht classification is based on the dominance of the front dental sector, expression of the interaction between shape (skeletal component - alveolar processes / teeth) and function (muscle component - buccal muscle corridor), evident in the relationship that is created between lips and teeth, determined by the interaction during phonation, mastication, etc.

Dominance 1 , sextant front teeth with volumetrically small teeth aligned in anteroposterior direction, weak individual dominance and horizontal symmetry.

Dominance 2, central incisors volumetrically prominent in anteroposterior direction, strong dominance of the two central incisors.

Dominance 3, sextant front teeth with volumetrically important teeth not aligned in anteroposterior direction, strong individual dominance.

Dominance 4, sextant front teeth with volumetrically important teeth aligned in anteroposterior direction, average individual dominance and radial symmetry.

The use of this information allows, if working in analog mode, the design and construction of dental dominances of the front teeth with characteristics defined in relation to the shape of the lips of the patient. If working in assisted software mode, it allows positioning of the natural and commercial artificial teeth with characteristics defined in relation to the shape of the lips, determining the dominance on the Y coordinate of the sextant front teeth, thus structuring the dental libraries from which to choose for designing in relation to the patient to undergo restoration.

The shape of the nose is defined.

The Gerber classification is based on the relationship between base and wings of the nose, an expression of the influence of the sphenoid on the position of the bone of the upper part, hence eye line, maxillary and nose. The relationship between the base and the wings of the nose is an expression on the frontal plane of the height relationship between the central incisors and the lateral incisors,

Nose 1 , central and lateral incisors almost aligned.

Nose 2, central and lateral incisors misaligned.

Nose 3, central and lateral incisors highly misaligned.

The use of this information allows, if working in analog mode, the design and construction on the frontal plane of the height relationship between the central incisors and the lateral incisors with characteristics defined in relation to the shape of the nose of the patient. If working in assisted software mode, it allows positioning of the natural and commercial artificial teeth with characteristics defined in relation to the shape of the nose, determining the dominance on the Z coordinate of the 4 front teeth, thus structuring the dental libraries from which to choose for designing in relation to the patient to undergo restoration.

The shape of the cranium is defined.

The osteopathic classification is based on the four physiological cranial harmonies. Harmonies with cranial volumetric differences that are also reproduced in the volumes of the dental arches and in the lingual volumes, influencing the dental positions and the occlusal plane in its entirety. Reproduction that with different degrees in relation to the patient, remains physiological while the harmonies find adaptive compensations, maintaining the balance and preserving the function in the absence of pain. Balance expression of a well-defined spatial dental relationship in left/right torsion and in left/right lateral flexion rotation.

In left torsion (the right is the opposite), the front dental group is inclined with the lower right canine and the upper left canine, the sixth teeth have the central fossae almost parallel in relation to the floor, but Von Spee and Wilson compensatory curves increased on the right and decreased on the left.

The dental cardinal points are relatively symmetrical and aligned along the growth lines.

This influences the occlusal plane with a slight inclination to the right.

In right lateral flexion rotation (left is the opposite), the front dental group is inclined to the right with the lower right and upper left canine, the back dental group on the contrary is inclined to the left with the central fossa of the lower left and upper right molar, determining Von Spee compensatory curves decreased on the right and increased on the left, Wilson compensatory curves decreased on the left and increased on the right.

The dental cardinal points are asymmetrical, hence not aligned along the growth lines with an opposite compensatory logic that causes the dental cardinal points of the upper model to anteriorise on the left and posteriorise on the right and the cardinal points of the lower model to do the opposite, i.e., to anteriorise on the right and posteriorise on the left.

Adaptive compensation that causes a cross or a vestibularisation/rotation of the distal side of 35 towards the outside.

This influences the occlusal plane with an inclination to the left, at molar level and, with an opposite compensatory logic, of the front dental group with an inclination to the right.

The three-dimensional actions influenced by the cranial harmonies act on the volume of the dental arches influencing them in the three planes of space with characteristics that reflect, with different degrees in relation to the individuality of the patient, these two types of patterns.

To structure the relationship of balance of the left torsion, the basic dental library symmetries are modified.

Upper and lower anterior block for the frontal plane Z coordinate:

• position on the median point between the highest tips of the mesial incisal margins of the two lower central incisors and rotate counter-clockwise by 1 -2° the upper and lower sextant front teeth.

Upper and lower posterior block for the sagittal plane Y coordinate:

• position on the cusp of 16 and incline upper and lower 6/5/4 rotating the right side counter-clockwise by 2° raising them at the front,

• position on the cusp of 26 and incline upper and lower 6/5/4 rotating the right side counter-clockwise by 1 ° lowering them at the front.

Upper and lower posterior block for the horizontal plane X coordinate:

• position on the cusp of 16 and rotate upper and lower 6/5/4 clockwise closing the right side by 2°,

• position on the cusp of 26 and rotate upper and lower 6/5/4 clockwise opening the left side by 2°.

Upper and lower posterior block for the frontal plane Z coordinate:

• position on the cusp of 16 and rotate upper right 6/5/4 counter clockwise opening the right side by 2°,

• position on the cusp of 26 and rotate upper left 6/5/4 counter-clockwise closing the left side by 2°,

• position at the centre of the occlusal surface of 46 and rotate lower right 6/5/4 clockwise closing the right side by 2°,

• position at the centre of the occlusal surface of 36 and rotate lower 6/5/4 clockwise opening the left side by 2°.

Upper superior block for the horizontal plane X coordinate:

• position at the centre of the incisal margin of 12 and rotate the three front elements of the right side in counter-clockwise direction by 1 -2° opening the central incisor,

• position at the centre of the incisal margin of 22 and rotate the three front elements of the left side in counter-clockwise direction by 1 -2° closing the central incisor.

Lower anterior block for the horizontal plane X coordinate: • position at the centre of the incisal margin of left 32 and rotate the three front elements of the left side in clockwise direction by 1 -2° closing the central incisor,

• position at the centre of the incisal margin of right 42 and rotate the three front elements of the right side in clockwise direction by 1 -2° opening the central incisor.

Block of seventh teeth if used for the sagittal plane Y coordinate:

• position at the centre of the mesial margin of 37 and move the left block of the two seventh teeth rotating in counter-clockwise direction raising them at the back by 1 -2°,

• position at the centre of the mesial margin of 47 and move the right block of the two seventh teeth rotating in clockwise direction raising them at the back by 3-4°.

Block of seventh teeth if used for the frontal plane Z coordinate:

• position on the lingual cusp of 37 and move the left block of the two seventh teeth rotating in clockwise direction raising the vestibulars by 3-4°,

• position on the lingual cusp of 47 and move the right block of the two seventh teeth rotating clockwise raising the vestibulars by 1 -2°.

Block of seventh teeth if used for the horizontal plane X coordinate.

• position at the centre of the mesial margin of 37 and move the left block of the two seventh teeth rotating in counter-clockwise direction opening them by 1 -2°,

• position at the centre of the distal margin of 47 and move the right block of the two seventh teeth rotating clockwise closing them by 1 -2°.

To structure the relationship of balance of the right lateral flexion rotation, the basic dental libraries are modified as follows.

Upper and lower anterior block for the frontal plane Z coordinate: • position on the median point between the highest tips of the mesial incisal margins of the two lower central incisors and rotate the upper and lower sextant front teeth in counter-clockwise direction by 1 -2°.

Upper posterior block for the horizontal plane X coordinate:

• position on the lingual cusp of 26 and anteriorise all the diatorics from the left side by 0.3-0.5 mm. and posteriorise those of the right side by 0.3-0.5 mm,

• position at the centre of the mesial margin of 24 and rotate all the diatorics in counter-clockwise direction opening the left side by 2-3°,

• position at the occlusal centre of 15 and rotate all the diatorics in clockwise direction closing the right side by 2°.

Lower posterior block for the horizontal plane X coordinate:

• position at the occlusal centre of 46 and anteriorise all the diatorics of the right side by 0.3-0.5 mm and posteriorise those of the left side by 0.3-0.5 mm,

• position at the occlusal centre of 45 and rotate only the premolars in counter-clockwise direction closing the right side by 2°,

• position at the centre of the mesial margin of 34 and rotate only the premolars in clockwise direction opening the left side by 2°.

Upper and lower posterior block for the sagittal plane Y coordinate:

• position on the vestibular point of 25 and incline upper and lower 5/6 rotating the left side in clockwise direction by 2° lowering them at the back,

• position on the vestibular point of 15 and incline upper and lower 5/4 rotating the right side counter-clockwise by 2° raising them at the front.

Upper and lower posterior block for the frontal plane Z coordinate:

• position at the occlusal centre of 36 and move the left block of the two sixth teeth rotating in counter-clockwise direction raising the vestibulars by 3-4°, • position at the occlusal centre of 46 and move the right block of the two sixes rotating in clockwise direction lowering the vestibulars by 1 -2°.

Upper and lower posterior block for the horizontal plane X coordinate:

• position at the occlusal centre of 36 and rotate it in clockwise direction by 1 °,

• position at the occlusal centre of 34 and rotate it in counter-clockwise direction by 1 °.

Upper anterior block for the horizontal plane X coordinate:

• position at the centre of the incisal margin of 22 and rotate the three front elements of the left side in clockwise direction by 1 -2° opening the central incisor,

• position at the centre of the incisal margin of 12 and rotate the three front elements of the right side in clockwise direction by 1 -2° closing the central incisor.

Lower anterior block for the horizontal plane X coordinate:

• position at the centre of the left incisal margin of 32 and rotate the three front elements of the left side in counter-clockwise direction by 1 -2° opening the central incisor,

• position at the centre of the right incisal margin of 42 and rotate the three front elements of the right side in counter-clockwise direction by 1 -2° closing the central incisor.

Block of seventh teeth if used for the sagittal plane Y coordinate:

• position at the centre of the mesial margin of 37 and move the left block of the two seventh teeth rotating in counter-clockwise direction raising them at the back by 3-4°, • position at the centre of the mesial margin of 47 and move the right block of the two seventh teeth rotating in clockwise direction, raising them at the back by 1 -2°.

Block of seventh teeth if used for the frontal plane Z coordinate:

• position on the lingual cusp of 47 and move the left block of the two seventh teeth rotating in clockwise direction raising the vestibulars by 2/3°,

• position on the lingual cusp of 37 and move the right block of the two seventh teeth rotating in clockwise direction raising the vestibulars by 3-4°.

The use of this information allows, if working in analog mode, using the relevant Bio-volumetric Template, the design and construction of the relationships of position between the teeth in relation to the cranial harmony of the patient to undergo restoration. If working in assisted software mode, using the relevant Bio-volumetric Template, it allows a criterion to be obtained for determining the relationships of position between the teeth, thus structuring the dental libraries with natural or artificial commercial teeth (acquired with scanner), in relation to cranial harmony.

The use of all the information in relation to the biotype, to the shape of the lips, to the shape of the nose and to cranial harmony, together helps to structure integrated basic dental libraries from which to start the design, choosing the most suitable and then individualising it in relation to the patient.

Claims

1. A method for individual dental design of a patient comprising the following steps:

classifying said patient;

determining the occlusal plane and the intermaxillary relationship of said patient;

spatially positioning the dental arches of said patient by means of cranial or facial scans; in the case of cranial scan an average is calculated in the three planes of space between the skeletal landmarks; in the case of facial scan an average is calculated in the three planes of space of the cutaneous landmarks;

selecting the bio-volumetric templates and the dental libraries suitable for said patient;

calibrating said bio-volumetric templates and the dental libraries;

positioning said bio-volumetric templates and the dental libraries;

designing the dental arches of said patient in relation to what was determined previously;

said step of determining the occlusal plane and the intermaxillary relation during swallowing of said patient comprises the steps of:

using the aesthetic line, which is the line tangent to the bipupil line and parallel to the 6 lower front teeth;

using the Frankfort plane; using the Camper’s plane;

said step of designing the dental arches of said patient comprises the steps of using an integrated basic dental library;

said integrated basic dental library defines the teeth positioned in the space classified based on the bio-volumetric templates, on the biotype, on the shape of the teeth, on the shape of the lips, on the shape of the nose and on the shape of the cranium;

said bio-volumetric templates are determined based on the biotype to which said patient belongs and identifying the inclination of the Von Spee and Wilson curves;

said dental libraries comprise information in relation to the biotype, to the shape of the teeth, to the shape of the lips, to the shape of the nose and to the shape of the cranium.

2. The method in accordance with claim 1 , characterised in that said step of classifying said patient comprises the steps of determining the biotype of the patient; determining the osteopathic classification; defining the type of lips; defining the type of nose.

3. The method in accordance with one of the preceding claims, characterised in that said step of spatially positioning the dental arches of said patient comprises the steps of scanning the upper/lower dental arches and, if possible, face and cranium.

4. The method in accordance with one of the preceding claims, characterised in that said step of selecting the bio-volumetric templates suitable for said patient comprises the steps of determining the biotype to which said patient belongs; identifying the inclination of the Von Spee and Wilson curves; determining the dimensions of a flat template and of a cup template, based on the information obtained in the preceding steps and based on the size of the teeth.

5. The method in accordance with one of the preceding claims, characterised in that said step of calibrating said bio-volumetric templates comprises the steps of using, if partially edentulous or totally edentulous Wheeler’s statistical measurements, with which it is possible to calculate the measurements of the missing teeth.

6. The method in accordance with one of the preceding claims, characterised in that said step of positioning said bio-volumetric templates comprises the steps of positioning them using the occlusal reference plane and the maxillary and mandible bone/muscle landmarks.