Aligner Interproximal Reduction Plan - Definitions - German Dental FHIR Profiles (R4) v0.41.6

German Dental FHIR Profiles (R4) - Local Development build (v0.41.6) built by the FHIR (HL7® FHIR® Standard) Build Tools. See the Directory of published versions

Extension: AlignerInterproximalReductionPlanExt - Detailed Descriptions

Active as of 2026-07-29

Definitions for the aligner-interproximal-reduction-plan extension.

Key Elements Table
Differential Elements Table
Snapshot Elements Table

Guidance on how to interpret the contents of this table can be foundhere

0. Extension
Definition	Planned interproximal reduction amount between two FDI tooth positions. Optional Extension Element - found in all resources.
Short	Aligner Interproximal Reduction PlanOptional Extensions Element
Control	0..* This element is affected by the following invariants: ele-1
Is Modifier	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
2. Extension.extension
Definition	An Extension May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	ExtensionAdditional content defined by implementations
Comments	There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
Control	30..*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
Slicing	This element introduces a set of slices on `Extension.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
4. Extension.extension:firstTooth
Slice Name	firstTooth
Definition	An Extension
Short	ExtensionAdditional content defined by implementations
Control	10..1*
Type	Extension
Is Modifier	false
Must Support	true
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
6. Extension.extension:firstTooth.extension
Definition	An Extension May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	ExtensionAdditional content defined by implementations
Comments	There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
Control	0..0*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
Slicing	This element introduces a set of slices on `Extension.extension.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
8. Extension.extension:firstTooth.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Short	identifies the meaning of the extension
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control	1..1
Type	uri
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
Fixed Value	`firstTooth`
10. Extension.extension:firstTooth.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short	Value of extension
Control	0..1
Binding	The codes SHALL be taken from For codes, see Zahnidentifikation nach FDI/ISO 3950 (required to `https://fhir.cognovis.de/dental/ValueSet/tooth-identification-fdi`)
Type	code, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, Coding, SampledData, id, positiveInt, Distance, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, CodeableConcept, ParameterDefinition, dateTime, string, Contributor, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, Signature, unsignedInt, time
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
12. Extension.extension:secondTooth
Slice Name	secondTooth
Definition	An Extension
Short	ExtensionAdditional content defined by implementations
Control	10..1*
Type	Extension
Is Modifier	false
Must Support	true
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
14. Extension.extension:secondTooth.extension
Definition	An Extension May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	ExtensionAdditional content defined by implementations
Comments	There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
Control	0..0*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
Slicing	This element introduces a set of slices on `Extension.extension.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
16. Extension.extension:secondTooth.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Short	identifies the meaning of the extension
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control	1..1
Type	uri
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
Fixed Value	`secondTooth`
18. Extension.extension:secondTooth.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short	Value of extension
Control	0..1
Binding	The codes SHALL be taken from For codes, see Zahnidentifikation nach FDI/ISO 3950 (required to `https://fhir.cognovis.de/dental/ValueSet/tooth-identification-fdi`)
Type	code, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, Coding, SampledData, id, positiveInt, Distance, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, CodeableConcept, ParameterDefinition, dateTime, string, Contributor, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, Signature, unsignedInt, time
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
20. Extension.extension:amount
Slice Name	amount
Definition	An Extension
Short	ExtensionAdditional content defined by implementations
Control	10..1*
Type	Extension
Is Modifier	false
Must Support	true
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
22. Extension.extension:amount.extension
Definition	An Extension May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	ExtensionAdditional content defined by implementations
Comments	There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
Control	0..0*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
Slicing	This element introduces a set of slices on `Extension.extension.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
24. Extension.extension:amount.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Short	identifies the meaning of the extension
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control	1..1
Type	uri
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
Fixed Value	`amount`
26. Extension.extension:amount.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short	Value of extension
Control	0..1
Type	Quantity, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, Coding, SampledData, id, positiveInt, Distance, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, CodeableConcept, ParameterDefinition, dateTime, code, string, Contributor, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, uri, url, Annotation, ContactDetail, boolean, Expression, Signature, unsignedInt, time
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
28. Extension.extension:amount.value[x].comparator
Definition	How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value.
Short	< \| <= \| >= \| > - how to understand the value
Control	0..1
Binding	The codes SHALL be taken from QuantityComparatorhttp://hl7.org/fhir/ValueSet/quantity-comparator\|4.0.1 (required to `http://hl7.org/fhir/ValueSet/quantity-comparator\|4.0.1`) How the Quantity should be understood and represented.
Type	code
Is Modifier	true because This is labeled as "Is Modifier" because the comparator modifies the interpretation of the value significantly. If there is no comparator, then there is no modification of the value
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Requirements	Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.
Meaning if Missing	If there is no comparator, then there is no modification of the value
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
30. Extension.extension:amount.value[x].system
Definition	The identification of the system that provides the coded form of the unit.
Short	System that defines coded unit form
Control	0..1 This element is affected by the following invariants: qty-3
Type	uri
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Requirements	Need to know the system that defines the coded form of the unit.
Pattern Value	`http://unitsofmeasure.org`
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
32. Extension.extension:amount.value[x].code
Definition	A computer processable form of the unit in some unit representation system.
Short	Coded form of the unit
Comments	The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system.
Control	0..1
Type	code
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Requirements	Need a computable form of the unit that is fixed across all forms. UCUM provides this for quantities, but SNOMED CT provides many units of interest.
Pattern Value	`mm`
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
34. Extension.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Short	identifies the meaning of the extension
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control	1..1
Type	uri
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
Fixed Value	`https://fhir.cognovis.de/dental/StructureDefinition/aligner-interproximal-reduction-plan`
36. Extension.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short	Value of extension
Control	0..01
Type	Choice of: base64Binary, boolean, canonical, code, date, dateTime, decimal, id, instant, integer, markdown, oid, positiveInt, string, time, unsignedInt, uri, url, uuid, Address, Age, Annotation, Attachment, CodeableConcept, Coding, ContactPoint, Count, Distance, Duration, HumanName, Identifier, Money, Period, Quantity, Range, Ratio, Reference, SampledData, Signature, Timing, ContactDetail, Contributor, DataRequirement, Expression, ParameterDefinition, RelatedArtifact, TriggerDefinition, UsageContext, Dosage, Meta
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))

Guidance on how to interpret the contents of this table can be foundhere

0. Extension
Definition	Planned interproximal reduction amount between two FDI tooth positions.
Short	Aligner Interproximal Reduction Plan
2. Extension.extension
Control	3..?
4. Extension.extension:firstTooth
Slice Name	firstTooth
Control	1..1
Must Support	true
6. Extension.extension:firstTooth.extension
Control	0..0
8. Extension.extension:firstTooth.url
Fixed Value	`firstTooth`
10. Extension.extension:firstTooth.value[x]
Binding	The codes SHALL be taken from Zahnidentifikation nach FDI/ISO 3950 (required to `https://fhir.cognovis.de/dental/ValueSet/tooth-identification-fdi`)
Type	code
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
12. Extension.extension:secondTooth
Slice Name	secondTooth
Control	1..1
Must Support	true
14. Extension.extension:secondTooth.extension
Control	0..0
16. Extension.extension:secondTooth.url
Fixed Value	`secondTooth`
18. Extension.extension:secondTooth.value[x]
Binding	The codes SHALL be taken from Zahnidentifikation nach FDI/ISO 3950 (required to `https://fhir.cognovis.de/dental/ValueSet/tooth-identification-fdi`)
Type	code
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
20. Extension.extension:amount
Slice Name	amount
Control	1..1
Must Support	true
22. Extension.extension:amount.extension
Control	0..0
24. Extension.extension:amount.url
Fixed Value	`amount`
26. Extension.extension:amount.value[x]
Type	Quantity
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
28. Extension.extension:amount.value[x].system
Pattern Value	`http://unitsofmeasure.org`
30. Extension.extension:amount.value[x].code
Pattern Value	`mm`
32. Extension.url
Fixed Value	`https://fhir.cognovis.de/dental/StructureDefinition/aligner-interproximal-reduction-plan`
34. Extension.value[x]
Control	0..0

Guidance on how to interpret the contents of this table can be foundhere

0. Extension
Definition	Planned interproximal reduction amount between two FDI tooth positions.
Short	Aligner Interproximal Reduction Plan
Control	0..* This element is affected by the following invariants: ele-1
Is Modifier	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
2. Extension.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
4. Extension.extension
Definition	An Extension
Short	Extension
Control	3..*
Type	Extension
Is Modifier	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
Slicing	This element introduces a set of slices on `Extension.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
6. Extension.extension:firstTooth
Slice Name	firstTooth
Definition	An Extension
Short	Extension
Control	1..1
Type	Extension
Is Modifier	false
Must Support	true
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
8. Extension.extension:firstTooth.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
10. Extension.extension:firstTooth.extension
Definition	An Extension
Short	Extension
Control	0..0
Type	Extension
Is Modifier	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
Slicing	This element introduces a set of slices on `Extension.extension.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
12. Extension.extension:firstTooth.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Short	identifies the meaning of the extension
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control	1..1
Type	uri
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
Fixed Value	`firstTooth`
14. Extension.extension:firstTooth.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short	Value of extension
Control	0..1
Binding	The codes SHALL be taken from Zahnidentifikation nach FDI/ISO 3950 (required to `https://fhir.cognovis.de/dental/ValueSet/tooth-identification-fdi`)
Type	code
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
16. Extension.extension:secondTooth
Slice Name	secondTooth
Definition	An Extension
Short	Extension
Control	1..1
Type	Extension
Is Modifier	false
Must Support	true
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
18. Extension.extension:secondTooth.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
20. Extension.extension:secondTooth.extension
Definition	An Extension
Short	Extension
Control	0..0
Type	Extension
Is Modifier	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
Slicing	This element introduces a set of slices on `Extension.extension.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
22. Extension.extension:secondTooth.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Short	identifies the meaning of the extension
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control	1..1
Type	uri
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
Fixed Value	`secondTooth`
24. Extension.extension:secondTooth.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short	Value of extension
Control	0..1
Binding	The codes SHALL be taken from Zahnidentifikation nach FDI/ISO 3950 (required to `https://fhir.cognovis.de/dental/ValueSet/tooth-identification-fdi`)
Type	code
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
26. Extension.extension:amount
Slice Name	amount
Definition	An Extension
Short	Extension
Control	1..1
Type	Extension
Is Modifier	false
Must Support	true
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
28. Extension.extension:amount.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
30. Extension.extension:amount.extension
Definition	An Extension
Short	Extension
Control	0..0
Type	Extension
Is Modifier	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
Slicing	This element introduces a set of slices on `Extension.extension.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
32. Extension.extension:amount.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Short	identifies the meaning of the extension
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control	1..1
Type	uri
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
Fixed Value	`amount`
34. Extension.extension:amount.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short	Value of extension
Control	0..1
Type	Quantity
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
36. Extension.extension:amount.value[x].id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
38. Extension.extension:amount.value[x].extension
Definition	May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	Additional content defined by implementations
Comments	There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
Control	0..*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
Slicing	This element introduces a set of slices on `Extension.extension.value[x].extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
40. Extension.extension:amount.value[x].value
Definition	The value of the measured amount. The value includes an implicit precision in the presentation of the value.
Short	Numerical value (with implicit precision)
Comments	The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books).
Control	0..1
Type	decimal
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Requirements	Precision is handled implicitly in almost all cases of measurement.
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
42. Extension.extension:amount.value[x].comparator
Definition	How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value.
Short	< \| <= \| >= \| > - how to understand the value
Control	0..1
Binding	The codes SHALL be taken from QuantityComparator (required to `http://hl7.org/fhir/ValueSet/quantity-comparator\|4.0.1`) How the Quantity should be understood and represented.
Type	code
Is Modifier	true because This is labeled as "Is Modifier" because the comparator modifies the interpretation of the value significantly. If there is no comparator, then there is no modification of the value
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Requirements	Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.
Meaning if Missing	If there is no comparator, then there is no modification of the value
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
44. Extension.extension:amount.value[x].unit
Definition	A human-readable form of the unit.
Short	Unit representation
Control	0..1
Type	string
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Requirements	There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
46. Extension.extension:amount.value[x].system
Definition	The identification of the system that provides the coded form of the unit.
Short	System that defines coded unit form
Control	0..1 This element is affected by the following invariants: qty-3
Type	uri
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Requirements	Need to know the system that defines the coded form of the unit.
Pattern Value	`http://unitsofmeasure.org`
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
48. Extension.extension:amount.value[x].code
Definition	A computer processable form of the unit in some unit representation system.
Short	Coded form of the unit
Comments	The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system.
Control	0..1
Type	code
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Requirements	Need a computable form of the unit that is fixed across all forms. UCUM provides this for quantities, but SNOMED CT provides many units of interest.
Pattern Value	`mm`
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
50. Extension.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Short	identifies the meaning of the extension
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control	1..1
Type	uri
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
Fixed Value	`https://fhir.cognovis.de/dental/StructureDefinition/aligner-interproximal-reduction-plan`
52. Extension.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short	Value of extension
Control	0..0
Type	Choice of: base64Binary, boolean, canonical, code, date, dateTime, decimal, id, instant, integer, markdown, oid, positiveInt, string, time, unsignedInt, uri, url, uuid, Address, Age, Annotation, Attachment, CodeableConcept, Coding, ContactPoint, Count, Distance, Duration, HumanName, Identifier, Money, Period, Quantity, Range, Ratio, Reference, SampledData, Signature, Timing, ContactDetail, Contributor, DataRequirement, Expression, ParameterDefinition, RelatedArtifact, TriggerDefinition, UsageContext, Dosage, Meta
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)