This document defines and describes various types of malocclusion, including deviations in individual tooth positions, relationships between dental arches, and classifications of malocclusion. It discusses Angle's classification system which categorizes malocclusion into three main classes (Class 1, 2, 3) based on the mesiodistal relationship between the upper and lower first molars. Various subdivisions and characteristics of each class are provided. The validity of Angle's classification is questioned as it does not fully differentiate skeletal from dental relationships or account for vertical and transverse anomalies.
Frankles appliance Is a myofunctional appliance
Functional appliance are removable or fixed appliances that aim to utilize eliminate or guide the forces arising from muscle function,tooth eruption and growth inorder to alter skeletal and dental relationship
Prosthodontics seminar 3rd stage University of Anbar College Of Dentistry
Created By Mohammed Amer Hekma
Supervised by: Dr Osama Abdul Rasool Hammoodi
References
• FUNDAMENTALS OF REMOVABLE PARTIAL PROSTHODONTIC DESIGN by Kenneth R. McHenry, D.D.S., M.S and Terrence McLean, D.D.S.
• Stewart's Clinical Removable Partial Prosthodontics, Fourth Edition by Rodney D Phoenix, D.D.S, M.S, David R Cagna, D.M.D, M.S and Charles F DeFreest, D.D.S
• McCRACKEN’S REMOVABLE PARTIAL PROSTHODONTICS, TWELFTH EDITION BY Alan B. Carr, D.M.D, M.S, and David T. Brown, DDS, MS
Frankles appliance Is a myofunctional appliance
Functional appliance are removable or fixed appliances that aim to utilize eliminate or guide the forces arising from muscle function,tooth eruption and growth inorder to alter skeletal and dental relationship
Prosthodontics seminar 3rd stage University of Anbar College Of Dentistry
Created By Mohammed Amer Hekma
Supervised by: Dr Osama Abdul Rasool Hammoodi
References
• FUNDAMENTALS OF REMOVABLE PARTIAL PROSTHODONTIC DESIGN by Kenneth R. McHenry, D.D.S., M.S and Terrence McLean, D.D.S.
• Stewart's Clinical Removable Partial Prosthodontics, Fourth Edition by Rodney D Phoenix, D.D.S, M.S, David R Cagna, D.M.D, M.S and Charles F DeFreest, D.D.S
• McCRACKEN’S REMOVABLE PARTIAL PROSTHODONTICS, TWELFTH EDITION BY Alan B. Carr, D.M.D, M.S, and David T. Brown, DDS, MS
normal and abnormal occlusion for general practitioners.docxDr.Mohammed Alruby
Normal and abnormal occlusion
For general practitioners
Prepared by
Dr. M Alruby
Normal occlusion
it is the usual or accepted relationship for species of teeth in the same jaw and those in the opposing jaw when the teeth are approximated in terminal occlusion and mandibular condyles are in centric position in the glenoid fossa
Normal occlusion in deciduous dentition
1= except the deciduous molars all other teeth are spaced and this spacing is rule or at least not abnormal.
2= curve of spee is less marked than the permanent teeth because:
= Short arch length anteroposterior.
= The cusps of posterior teeth are short and occlusal plane is flat.
3= the buccal cusps of maxillary deciduous molars and the incisal edge of maxillary deciduous incisors overlaps the mandibular one but the degree of overlaps differ because of short cusps.
4= the maxillary incisors and canines are larger than the mandibular one and the mandibular molars are larger than the maxillary one.
5= the long axis of the teeth are nearly parallel to each other.
6= the midline rule and arch symmetry similar to the permanent dentition.
7= all the maxillary teeth except 2nd deciduous molars occlude with two opposing teeth
Occlusal relationship of primary molars:
1= flush terminal plane: occurs where the primary erupt in an end to end fashion
2= A mesial step: is where the distal surface of the mandibular second primary molars is mesial to the distal surface of the second primary maxillary molar, that leads to Class I molars relationship
3= A Distal step: is where the distal surface of the mandibular second primary molar is distal to the distal surface of the second primary maxillary molars leads to class II molar relationship
Figure (1): flush terminal plane figure (2) mesial step figure (3) distal step
Characteristics of normal occlusion in permanent dentition:
1= each arch is regular with the teeth at ideal mesiodistal and buccolingual inclination and the correct proximal contact relationship at each interdental contact area.
2= All teeth must be angulated mesially.
3- The buccal surfaces of incisors are labially inclined, but from the canines posteriorly, the buccal surfaces are progressively more lingually inclined.
4=the dental arch relationships are such that:
= each lower tooth except central incisors contact the corresponding upper tooth and tooth anterior to it.
= the upper arch overlaps the lower arch anteriorly and laterally
Six keys to normal occlusion:
(1) Molar relationship:
*- The mesiobuccal cusp of the upper 1st permanent molar falls within the groove between the mesial and middle cusps of the 1st permanent molar.
*- The mesiopalatal cusp of the upper 1st permanent molar seat in the central fossa of the lower 1st permanent molar.
*- The distal surface of the distal marginal ridge of the upper 1st permanent molar contact and occlude with the mesial surface of the mesial marginal ridge o
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Types of malocclusion
Malocclusion can occur singly or in combination as follows:
1- Dental mal-relationship.
2- Dento-alveolar, involving the teeth and alveolar process.
3- Dental arch mal- relationship
4- Basal arch discrepancy
5- Cranio-facial abnormalities.
1- Dental mal relationship
Including crowding, spacing, ectopism and other local malposition of the teeth that not affect the arch size, relationship and growth.
Causes of dental malposition:
1- genetic factors.
2- Prolonged retention or early loss of primary teeth.
3- Delayed eruption of permanent teeth.
4- Supernumerary teeth, missing teeth, either congenital or due to extractions.
5- Ectopic eruption and abnormal tooth morphology.
6- Abnormal development of the teeth.
Frequency:
=The most frequently malposed teeth in permanent dentition are the 3rd molars, maxillary lateral incisors, mandibular incisors, 2nd premolars and 2nd molars, the less frequently malposed teeth are the 1st molars and 1st premolars.
= spacing is predominating in deciduous dentition while crowding is common in permanent dentition.
= Irregularities due to local pot natal causes will manifest themselves clinically and will requires corrective treatment.
= rotation of the teeth in most cases is a sequlea of crowding but sometimes occurs with spacing due to loss of proximal contact between the erupting and adjacent teeth.
= crowding and spacing of the same arch may be expected in deciduous dentition but if occurs in permanent dentition, it will represent a symptoms of tooth shifting and detective eruption due to local interfere.
Spacing of permanent teeth:
In the permanent dentition, spacing in the maxillary arch is usually localized from canine to canine.
The median diastema in maxillary arch may be caused by:
1- Abnormal labial Frenum or presence of mesiodense
2- Dwarfed or congenitally absent lateral incisors.
3- Or as a part of generalized spacing.
Spacing in the mandibular arch is less common but may occurs due to:
1- Abnormal large tongue and bi dental protrusion.
2- Abnormal lingual Frenum ----- median diastema.
3- As a part of generalized spacing.
Loss of space or space closure:
a- In mixed dentition:
= In children with well-developed arches, there is little or no space loss after extraction of primary molars, this may be due to the cuspal interlocking of U and L 6
= There will be more space loss after extraction of E then after extraction of D
= loss of UE before the eruption of UB causes the U6 to erupt far mesially toward UD occupying the space required for eruption of U5------ impaction of U5.
= in the mandibular arch the forward shifting of L6 is less great and space loss is less marked.
= the order of eruption of permanent teeth has some effect on determining the space closure. For example: the maxillary canine may block out labially because it erupts after U4, the mandibular 2nd bicuspids may block out lingually because it is the last tooth erupt in the front of L6.
b- In permanent
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Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
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This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
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Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
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Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
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ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
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Classification of malocclusion
1. Malocclusion
Malocclusion is defined as condition where there is a deviation from the normal relation of the teeth to
other teeth in the same arch and to teeth in the opposing arch .
It might be simple or complex .
Normal occlusion :- The mesiobuccal cusp of the max. first molar is aligned with the buccal groove of the man. first
molar.
- there is alignment of the teeth , normal overbite and overjet and coincident maxillary and mandibular
midlines.
A- Teeth :
1- Mesial inclination ;
Describes a tooth which is abnormally tilted so that its crown leans along the line of dental arch
toward the midline of the arch.
2- Mesial displacement ;
Describes a tooth which is bodily displaced towards the midline of the dental arch.
3- Distal inclination ;
The opposite of the mesial inclination , where the tooth tilted along line of dental arch so that its
crown too far away from the midline of the arch.
4- Distal displacement ;
Describes a tooth which is bodily displaced in adirection away from tha midline of the arch .
5- Lingual inclination ;
Refers to a tooth so tilted so that its crown leans toward the tongue.
Retro-clinatin is a term frequently used also to refer to the lingual tilting of the anterior teeth.
6- Lingual displacement ;
A tooth bodily displaced toward the tongue .
2. 7- Labial inclination ;
.A term used to describe the outward tilting of incisor and canine teeth towards the lips (proclination
may used to describe this condition ).
.In the case of the molars and premolars , the term “buccal” inclination is used .
.The composite term “vestibular” may be used to embrace both „labial‟ and buccal when indicating
the outer side of the dental arch.
8- Labial and buccal displacement ;
Is used similarly to describe bodily displacement of teeth in an outward direction.
9- Infraclusion;
A term used to describe a tooth of which the occlusal surface or incisal edge has not reached the
same leve as the rest of the teeth in the arch, i.e., it does not appear to have erupted sufficiently.
10- Supraclusion ;
The opposite of the infraclusion , i.e., the tooth appears to have “over-erupted” .
11- Mesiolingual rotation ;
Describes a tooth which is rotated around its long axis so that its mesial aspect is turned towards the
tongue .
12- Distolingual rotation ;
Describes a rotation in the opposite direction.
13- Imbrications
describes teeth ( especially lower incisors ) which are irregularly arranged within the arch due to lack
of space for them.
14- Transposition
is a term used to describe a condition where two teeth appear to have exchange places during the
development of occlusion. Perhaps this is most often seen where upper canine and an upper first
premolar or lateral incisor on the same side of the arch are transposed .
3. B- Dental arches :
could be in any direction :. Anteroposterior
. Vertival
. Transverse
1- post normal occlusion :
This is used to describe a condition where the lower dental arch appears to be too far-back in relation to
the upper arch when the teeth are closed in centric occlusion and the mandibular condyles are in their
normal position within the glenoid fossa.
2- Pre-normal occlusion ;
.This is used to describe a condition where the lower dental arch is in advance of the upper when teeth
are closed in centric occlusion and the condyles are in their normal position within the glenoid fossa.
. Psuedo…. .
3- Crossbite ;
It is a discrepancy in the baccolingual or in the transverse direction, on one or both sides.
The occlusion may be such that buccal cusps of one or more of the posterior teeth may occlude within
the fossa of the lowers . Lowers is wider than upper.
Where the discrepancy is mild it is likely that a cusp to cusp relationship of the teeth will cause
premature contact of the affected cusps as the jaws close .
In order to avoid this mandible may assume a position other than centric occlusion by deviation to one
side . This will give false impression that one side alone is affected.
Buccal crossbite ; in such a way that the buccal cusps pf the lower teeth occlude buccal to buccal cusps
of the upper teeth.
Lingual crossbite is a condition where the upper arch is completely contained within the lower or where
the lower arch is contained within the upper on closure . The buccal cusps of the lower teeth occlude
lingual to the lingual cusps of the upper teeth . This known as SCISSORS bite.
4- Open-bite ;
In these cases only the most distal teeth in the dental arch may occlude. When the jaws are closed , a
space exists between the rest of the teeth in the upper jaw and those of lower. Such space progressively
increases anteriorly.
4. 5- Bimaxillary protrusion ;
This is a forward or mesial position in the skull of both dental arches. Frequently the arches are of good
form, the teeth even , and the occlusion normal. The face seems full of teeth , especially with a smile.
.Extraction…
6- Deep overbite ;
Where the crown of the upper incisors cover more than one third of the lower when the teeth are in
centric occlusion.
.Deep impenging overbite , where the incisal edge of the loer teeth touch the palate ( complete overbite )
7- Incomplete overbite ;
It is a term used to indicate that vertical space exists between the lower incisors and the palatal aspects
of the upper incisors where the teeth are in centric occlusion .
This space may be penetrated by the tip of the tongue at rest , and during swallowing.
89- Increased interocclusal clearance ;( or increased free way space):
When a child closes jaws into centric occlusion there may be an increased incisor overbite which is
brought about by an excessive distance between the occlusal surfaces of the upper and lower posterior
teeth when the mandible is in the rest position.
C- Dental bases :
Dental base relations can be classified into the terms skeletal 1,2 or 3 in the anteroposterior direction
when the jaws are closed and the teeth are in full occlusion .
CLASS 1 ;
The bones of the face and jaws are in harmony with one another and with the rest of the head. The profile is
orthognathic.
CLASS 2 ;
.Subnormal , distal mandibular development in relation to the maxilla or postnormal relation of the dental
bases. The profile is retrognathic .
CLASS 3 ; .Overgrowth of the mandible and obtuse mandibular angle , the profile is prognathic at the
mandible or a prenormal relation of the dental bases .
5. Classification of malocclusion
The classification by Edward angle in 1899 produced a useful aid in diagnosis and treatment planning.
Angle used the roman numerals 1, 2, and 3 to designate the 3 main classes of mesiodistal arch relation. He
employed the Arabic numerals 1 and 2 to denote division of the classification.
Class 1:
The lower dental arch is at normal relation to the upper arch as evidenced by the occlusion of the mesiobuccal cusp of the upper 1st permanent molar in the buccal groove of the lower 1st permanent molar.
Providing no drifting of these teeth has occurred, and if the deciduous molars are still present, due
allowance has been made for the wider mesiodistal width of the lower deciduod molars.
A-Local abnormalities:
1.
2.
3.
4.
crowding of upper and lower incisors
labial inclination of uper anterior teeth with lower incisors in lingual inclination of varying degrees.
labial inclination of both upper and lower anterior teeth( bimaxillary, protrusion)
one or more of the upper anterior teeth are in lingual occlusion with the lower anterior teeth(anterior
cross-bite)
5. rotation of the incisors
6. posterior crossbite, uni or bilateral.
7. local abnormalities due to premature loss of deciduous molars which is often followed by forward tilt of
the permanent molars and loss of space for the premolars.
Extraction of permanent teeth, the presence of supernumerary teeth, absence of teeth and prolonged retention of
primary teeth are other local conditions, which give rise to abnormality in individual tooth position.
B-vertical malrelationship
1. excessive overbite: the majority of deep overbite problems can be divided into 2 categories. Skeletal and
dental.
Skeletal type or deep overbite may be due to either malrelation of alveloa bone and or underlying
mandibular or maxillary bones or to an overgrowth or undergrowth of alveolar segments
2. deficient or anterio open-bite: these cases the anterior teth are not in contact in all excursions of
mandible it may be the result of:
class 2:
typically the lower arch is in distal relation to the upper arch, the distobuccal cusp of upper 1st permanent
molar occludes in the buccal groove of the lower 1st molar, by an abnormal intercuspation of the premolars
to the extent of the lower 1st premolar occluding where the lower 2nd premolar normally occlude and by the
occlusion of the lower canine distal to the upper.
There are 2 divsions of class 2. Each capable of occurring on one side only, a condition described by the
suffix “unilateral” which has termed subdivision by angle.
6. Class 2 division 1
the upper incisors are proclined, such that the overjet may be as much as 14 mm.
the lower incisors frequently meet the palatal mucosa when the jaws are occluded.
short lip with failure in the anterior lip seal due to its unfavorable appearances which usually are often
accompanied by deep overbite.
an upper arch which is narrow in the canine and premolar region broadening between the molars and
giving rise to the typical V-shaped arch.
mandible may be deficient and chin underdeveloped.
mouth breathing may be present.
Class 2 division 1 subdivision:
It has same general characteristics except that its unilateral.
Class 2 division 2
the upper centrals show lingual inclination but may be overlapped by the upper laterals with the result of
their imbrication
upper arch is usually broad while incisors overbite is deep, both upper and lower incisors being in
apparent supra-occlusion.
both arches have a rather square appearance, this is due to lingual inclination of the incisors.
upper lip is of normal length and contacts he lower lip through there may be a deep mental groove below
the latter. These cases are often accompanied by prominent malar processes.
mandible is of good size
no mouth breathing involved
Class 3
The lower arch is at mesial relation to the upper arch in such a way that the lower 1st permanent molar
may be as much as a full premolar width mesial to upper 1st permanent molar, though there are often
lesser degree of mesial reation.
Incisors may occlude edge to edge, the lower incisors may be in advance of upper incisors or rarely the
lower incisors may still present their ncisal tips lingual to those of the upper incisors.
Class 3 devided into:
1- trueprenormality:
this always involves an anterioposterior relation of the dental bases. The mandible is either excessively
large or there is a lack of forward growth of the maxilla. In many cases there is a combination of both.
Therefor when the teeth are in centric occlusion, the mandibular condyles are within the glenoid fossae
and mandible cannot be retruded further than a mm or 2.
there are found to be hereditary other members of the family being affected.
pressure from lower lip causes lower incisors to inclined lingually, whereas pressure from the tongue
may cause the upper incisors to be inclined labially.
incisor overbite is small
7. 2-pseudo prenormality
this condition the mandible is protruded a little during the final stages of closure to avoid premature
contact of incisor or canine.
Its most likely to arise in cases where the relation of the incisors is edge to edge and may be caused by
mildly prenormal relation of dental base. Or by premature loss of upper molars.
Incisor overbite is large and the jaws have the appearance of being over closed when teeth are
approximated such psedo or postural class 3 cases may tend if untreated, where the condition is present
only on one side as it is referred to as unilateral.
Validity of angles classification
classification is without foundation for the following reasons:
1st permanent molars are not fixed points in skull anatomy
as it now realized it is possible to have the dental arches on one relation while basal bones at another, eg.
A dental arch class 2 might be superimposed upon skeletal class 1.
1-In class 2 cases the classification does not differentiate between true mandibular retrusion and
maxillary protrusion and also in class 3 cases doesn‟t differentiate between true mandibular protrusion
and maxillary retrusion.
2-angles classification is incomplete as a basis for diagnosis. It only attempts to embrace anomalies in
the anteroposterior direction. It cant be applied to differentiate anomalies in vertical nor transverse
directions.