Forensic Odontology Flashcards
Who sets the standards for dentists in the UK
General Dental Council
Must be followed
What are the roles of a forensic odontologist
Bite marks - identification and analysis/comparison
Ageing victims from their dentition
Victim identification based on dentition - can be single or multiple body or individual teeth
Bite mark analysis has many limitations - true or false
True
How did forensic odontology start
FO started with a Cuban dentist who taught in Paris (end of 19th century)
There was a fatal fire at charity event in Paris in 1897
They were unable to recognise bodies by personal effects so a team of dentists compared dental records to identify them
The Cuban dentist followed this case and wrote a paper on human identification from teeth/dental records
He is known as the father of the specialty
Can forensic odontologists identify someone from a single tooth
Yes
Obviously more teeth makes it more accurate
When is comparative dental analysis used
When we have access to the dental records of the victim/potential victim
When is dental profiling used
When we don’t have access to the dental records
Enamel is the hardest material in the human body - true or false
True
High stability - therefore good for identification as resistant to damage
What is enamel composed of
98% mineral and some organic material
This makes it very resilient
How can you get a DNA from a dental sample
Can get DNA from the pulp of the tooth (pulp relatively protected by the rest of tooth)
You extract the tooth from body to collect this
When does dental DNA come in useful
Useful if comparative analysis isn’t available as it can be used for ID instead
Forensic odontology can be applied at any stage of death - true or false
True
Can analyse the teeth of recent corpses, mummies and decomposed bodies
How do dentists record dentition in life
They will take notes of everything that is in your mouth such as missing teeth, fillings
Recorded on a odontogram - diagram of mouth
Will also write down the treatment plan
What is the main difference between AM and PM dental records
The AM records will usually include the treatment plan
PM records do not require this - obviously
How are AM dental records used for identification
The suspected patient’s AM record can be compared to the dentition of the corpse
Can match missing teeth and dental work
Which forms do forensic odontologists use to record their findings
They use Interpol forms - allows international use
Pink form records all data and findings from the PM
Yellow form collects all ante-mortem data - i.e. collected from police or victims dentist
Which investigations may a forensic odontologist carry out on a body at PM
Full oral examination and record findings
Dental radiographs
Intra-oral photographs
May take casts of the teeth
How are PM dental X-rays taken
Using a portable x-ray machine
Sensor placed in oral cavity and portable machine can take a digital X-ray quickly
What equipment do forensic odontologists use
Pretty much the same equipment as normal dentistry
Use large forceps to extract teeth for DNA
Also work with portable X-ray machines
Why do forensic odontologists typically work in the back corner of the mortuary
Because they work with radiation
Far away from other to keep them safe
Why do forensic odontologists use UV light
Sometimes used to view the composite on teeth (white or tooth coloured materials)
Used as it doesn’t show up under poor mortuary lighting
What is an odontogram
It is the diagram of the teeth that the dentist records features on
What is the main limitation of odontograms
Not perfect - human error
You rely on their interpretation of the individual dentist and their records
(unlike x-rays or images where you can view and analyse yourself)
Dentists may miss something in life
Forensic odontologists prefer to receive records that have proper images of the oral cavity - true or false
True
X-rays and photos are very useful
Allows for their own interpretation rather than relying on the odontogram
How might someone cosmetically alter their teeth
Tooth gems, gold, oral piercings, gum tattoo, grills
These are considered secondary identifiers as have been added to the oral cavity and could be there artefactually
Can grills be used for identification
Not reliable enough for identification
However, can be evidence if it has been specially made to fit the teeth
How can retainers and whitening trays be used for identification
They can give an idea of teeth layout/shape as based on impressions/cast of real teeth
Some may have numbers on them
Therefore can be used for identification
How can selfies be used for dental identification
Can compare teeth from photos to the body
You superimpose the image onto the unidentified teeth and compare measurements and unique features
Useful as selfies have good proximity to the teeth (within arms reach) and often use different angles
If you don’t have ante-mortem data then comparative analysis isn’t possible - true or false
True
Must use other methods to identify such as dental profiling - not impossible but harder
Why are teeth reliable for age estimation
They are relatively protected from diet or hormonal changes (compared to other tissue like bones)
Therefore the main impact is age
Not a perfect method
What are the key features of dental profiling
Age - most important
Sex
Ancestry
Teeth are good for sex estimation - true or false
False
Can be used but not very reliable
More accurate if pelvis and skull are analysed by anthropologist
How do the police decide which dental records to request when an unidentified body is found
If a body is found, the police can consult the missing persons database and ask family for dentist or find dentist themselves to get the appropriate records for comparison
The more teeth you have the more information you can collect - true or false
TRUE - makes the case easier
If someone is missing most of their teeth it limits the analysis you can do
What must forensic odontologist record in their dental report
The date/location when body was received
Who called them
What examinations/procedures were performed - in a lot of detail
Where any ante-mortem records where collected from
Compare AM and PM in detail
Conclusion
Must sign it
What are the 3 primary identifiers
Fingerprints
Teeth
DNA
How many primary identifiers are required for indication
Only one is required for identification but some coroners ask for at least 2
How was forensic odontology used in the Grenfell fire
67% of Grenfell victims were identified positively via forensic odontology
7% were possible/probable IDs due to lack of evidence or poor ante-mortem records
When DNA was considered alongside this they became positive IDs
What effect can heat have on the teeth
Usually quite resilient to heat
Effect determines by temp and length of exposure (of significant teeth can turn to ash - long time needed)
Can cause separation of crown and root (due to dehydration)
What is mixed dentition
When both milk teeth and permanent teeth present
The presence of mixed dentition suggests what
That the remains are that of a child
What tests can you do if you only have a single tooth to analyse
Must confirm it is a human tooth - macroscopic features
You then do microscopic analysis
Can then section the tooth and examine the dental histology
Forensic odontologists need to be able to distinguish human teeth from what
Animal teeth
May get mixed up in mass victim samples
Otherwise bite marks and remains can be incorrectly classified
In which age group is age estimation from teeth the most accurate
Children and adolescents
Lots of teeth to work with and lots of physiological changes occurring that can be staged - staging/scoring methods available
Assess and identify what stage of dental development the child is at
When do teeth start to age
Our teeth start to age slightly from age of 21-25
Regressive changes occur
Becomes more severe as age increases
Ageing from dentition is more challenging in adults - true or false
True
Only have the permanent dentition to work with and different features need assessed
Regressive change in the teeth becomes more obvious/severe as age increases - true or false
True
What happens to our teeth between the ages of 25-30
Start seeing transparency at end of root
This is due to dentine
How does dentine change with age
From age 25-30 = start seeing transparency at end of roots
Its spreads to the dental crown as age increases
How can third molar development be used in identification
It can be used to age/identify young adults
Will usually be developing between ages of 18-23 - can assess level of development
If absent = under 18
If fully developed = adult (harder to assess age)
What are the third molars also known as
Wisdom teeth
These are the last teeth to develop - come in between ages of 18-23
Which type of substrate makes bite marks easier to identify
Firmer substrates - hold shape of bite better (e.g. cheese and chocolate)
Those that do not decay - less likely for mark to be distorted
If part of tooth is left in substrate it’s very useful
Is skin a good substrate for bite marks
NO
It comes with lots of factors that contribute to distortion such as different layers, movement of victim
What can distort a bite mark left on skin
Primary factor is the skin itself - different layers, Langer’s lines, elasticity and movement/position of victim
Secondary distortion in photos
How can bite mark evidence be used in court
You can now only state whether the bite mark excludes the suspect or doesn’t exclude - requires a lot of experience
As a technique it has many limitations so is not reliable to base a conviction on (many past ones have since been thrown out)
Bite mark evidence has led to many wrongful imprisonments - true or false
TRUE
Experts didn’t acknowledge the limitations of the technique so this evidence was enough to convince the jury
What is involved in bite mark identification
First identify whether the bite mark is human
Then it is compared to possible suspect
They are then only excluded or not excluded - no exact identification
Why are some FOs reluctant to compare bite marks to a suspect
Due to limitations of the technique
Case reports should be written in pairs - true or false
True
Should be completed by 2 FOs
Especially in bite mark cases
What is dental neglect
When you get children with lots of decayed teeth
This suggests the parents are not taking care of their child’s hygiene - suggestive of general abuse/neglect
May also be seen in vulnerable elderly or disabled
What signs of sexual abuse may be seen on dental examination
STDs in the oral cavity
Physical evidence of forced oral sex
Abused children may react negatively to oral examination - very personal and up close which they may not like (also a sign of emotional abuse)
How can tooth decay suggest abuse
Tooth decay can be very painful so if you see a child with lots of it, it may suggest neglect
No seeing to the problem
FO’s are sometimes consulted on intraoral injuries - true or false
True
Work with the pathologist
Dentists are required to report any signs of suspected abuse - true or false
True
Is oral and facial trauma common in abuse cases
Yes
Occurs in around 50% of physical abuse cases
What is an endodontic procedure
Like root canal
Treatment of the dental canal
What are the risks of an endodontic procedure
Uses very small instruments - can fracture in canal
More prone to malpractice due to complications (must inform patient of mistake and correct it to avoid this)
List examples or dental negligence
Missing oral cancer diagnosis
Overlooking the soft tissues of the mouth and missing disease
If a dentist suggests a further appointment to investigate a serious issue and they don’t attend, is the dentist still at fault if they come to harm
No the dentist is not at fault
However, they must document the non-attendance
List examples of dental fraud
Using cheap materials for dental work
Dentists charging for more work than they actually do
Is dental fraud common
No not these days
Is it common to see bite marks in cases of sexual assault
Yes
Especially in ‘sexual areas’ such as breasts or close to genitals
When might a dentist be asked to investigate oral trauma
May be for insurance claim - e.g. Car accident
May ask for dental costs to be covered so insurance may request a dentist opinion to prove the accident was the cause of the dental problems
How was bite mark evidence used in the Bundy case
He had very unique, crooked teeth which were used for comparison
In general these days this would be only be used to rule in a suspect not convict
Define forensic odontology
It is a branch of forensic medicine and dentistry and deals with the proper examination, handling and presentation of dental evidence in a court of law
What is dental jurisprudence
A set of legal regulations set forth by each state’s legislature describing the legal limitations and regulations related to the practice of dentistry
General dental council in the UK
Describe the process of identification using comparative dental analysis
Post-mortem records are developed by the FOs
Ante-mortem records are retrieved
These 2 sets are compared
Which dental feature would suggest the deceased was Caucasian
Carabelli’s cusp
Small extra cusp on the first upper molars
Which dental feature would suggest the deceased was of Mongolian descent
Shovel-shaped upper central incisors
List secondary methods of identification
Personal data
Medical findings
Evidence and clothing
What are the 6 parameters in the Gustafson
Occlusal attrition Periodontitis Secondary dentine position - assess dentine/pulp ratio Cementum apposition Root resorption Root transparency
Which skin types tend to bruise more easily (i.e. from bite marks)
Females
Black skin
Infants and the elderly
Obese people
List the types of child abuse
Neglect
Physical
Sexual
Emotional
What is the most common site of oral injury
The lips (54%) Followed by oral mucosa, teeth, gingiva, and tongue
What effect may gags have on the mouth
May result in bruises or scarring at the corners of the mouth
What sign of abuse may be seen on oral examination of pre-mobile infant
Lacerations to the labial frenum
Considered an indicator of abuse
However, also seen in falls or trying to feed child (use a bit of force)
What can direct trauma to the teeth result in
Pulpal necrosis
This leaves the teeth grey and discoloured
How can dental work be used for identification
Ante-mortem imaging of dental bridges, fillings etc. can be compared to evidence
Especially useful if the dental work is unusual or identifiable
Used in the case of Hitler and Mengele
FO’s work in both civil and criminal courts - true or false
True
When might FOs need to identify multiple bodies
If there has been some sort of disaster and multiple victims need identified
Disaster victim recovery and identification
How do FOs report comparison of dentition
Can positively identify
Can report as possible of probable
Can also report that the suspect/potential victim is excluded
Which up and coming technique is expected to modernise dental records
Digital oral scans
Build a more accurate digital picture of the oral cavity
When might dental identification not be sufficient
Lack of evidence or poor ante-mortem records
Would use DNA alongside it to confirm in these cases
How can the cementum annuli be used for age estimation
The cementum is a dental tissue that surrounds the root and is laid down in layers
1 layer = approx 1 year of life
Invasive method
What is malpractice
When the professional doesnt follow the proper guidelines
usually with negative consequence
How can restorative procedures result in malpractice cases
If the dentist does not follow the natural anatomy of the tooth when reconstructing
This leads to many further dental issues = malpractice
List innovations in FO created by Dundee students
Dental record checklist listing key features - aids communication between dentist, police and FO
Website listing features of dental charts from across the world
An atlas of dental anomalies - aids identification/recording of features (should be recorded as an identifier)
Anatomical chart of oral jewelry/piercings/tattoos
3D diagram of dental damage
