Class II Division 2: Retroclined Incisors and Deep Bite
Class II division 2 is a Class II molar and canine relationship in which the upper central incisors, and sometimes all four upper incisors, are retroclined, with a deep bite. It is not a division 1 with the incisors turned the other way. University courses describe it as a distinct entity: a low-angle face, strong lip and masticatory muscles, a deep overbite and a skeletal discrepancy that is often small. This guide covers how to recognize it, what the cephalogram shows, the diagnostic traps, and the criteria that guide planning. It is written for dentists, residents and students; for a personal case, the assessment belongs to an orthodontist.
Division 1 vs division 2 at a glance
| Feature | Class II division 1 | Class II division 2 |
|---|---|---|
| Upper incisors | Proclined or normally inclined | Retroclined (centrals, or all four incisors) |
| Overjet | Increased | Normal or very small, often about 1 mm |
| Overbite | Variable; open bite possible | Deep bite (above 3 mm), always present |
| Lips | Often incompetent | Competent, tonic; lower lip high on the upper incisors |
| Vertical pattern | Variable: low-angle and high-angle forms are described | Usually low angle (reduced FMA, short lower face) |
| ANB | Usually increased | Highly variable, from −2° to +11° depending on the series |
| Interincisal angle | Normal or reduced | Increased, almost always above 140° (norm 131° ± 5°) |
| Lower arch crowding | Variable | Often apparent rather than real (the "lid effect") |
The thresholds in this table follow our D.U. course materials and the norms used across this site; the overbite and overjet definitions are detailed in our overjet and overbite guide.
How common is Class II division 2?
Figures vary with the source: about 10% of malocclusions according to our D.U. course, 2% to 3% of the population according to Parielle, 2% to 14% of treated malocclusions in the studies cited by Boileau. It is reported to be more frequent in adults, since a division 1 can evolve into a division 2 when the lower lip pushes the upper incisors back. On sex, the sources contradict each other: about three girls for one boy according to Parielle, less frequent in girls according to Bassigny.
Clinical signs
Face and profile
The face is often harmonious, which is a trap: a pleasant profile does not mean a mild malocclusion.
- Lips: thin and tonic, closed at rest without effort; short upper lip; everted lower lip lying high on the upper incisors; high stomion.
- Profile: concave below the nose, marked labiomental fold, closed gonial angle. In the primary form the chin is prominent but balanced; in the secondary form it is more retrusive.
- Vertical: reduced lower facial height, frequent gummy smile, and an increased freeway space (6 to 8 mm in the course materials).
Arches and occlusion
- Upper arch: short, wide and square, deep anterior palate; retroclined and overerupted incisors whose edges sit below the occlusal plane, giving a "step" in the occlusal plane distal to the canines.
- Lower arch: square or triangular, little crowding, deep curve of Spee, incisal wear facets.
- Interarch: Class II canines, Class II molars that are usually moderate, normal or very small overjet.
- Deep bite: more than 3 mm, sometimes with the lower incisors biting into the palate or the upper incisors into the lower labial gingiva, a common reason for consultation.
Look for associated dental anomalies (shape, number, position): 59% of Frapier’s 100 patients had one. Boileau points to two that will limit treatment: a crown-root angulation of the upper incisors, which limits torque, and a worn cingulum, which gives poor vertical stops. A panoramic radiograph is part of the records.
The three clinical forms
The courses use Bassigny’s three forms, in increasing severity:
| Form | Incisors | Features |
|---|---|---|
| 1 (most common) | Upper centrals retroclined, laterals proclined | The typical picture |
| 2 | Three or four upper incisors retroclined | Canines buccally displaced or impacted palatally |
| 3, "Deckbiss" (box lid) | The whole incisor-canine group retroclined, in deep bite | Reversed maxillary compensating curve, upper premolars in buccal crossbite; the most severe |
What the cephalogram shows
The lateral ceph of a division 2 is recognized mostly by:
- an interincisal angle almost always above 140°, against a Steiner norm of 131° ± 5°;
- a retroclined upper incisor, with a reduced U1-NA angle;
- a reduced divergence: low FMA (Tweed norm 25° ± 3°) and low SN-GoGn (Steiner norm 32° ± 5°), with anterior mandibular rotation;
- an ANB that varies widely, from −2° to +11° depending on the series.
Division 2 is therefore not defined by the size of the skeletal discrepancy. For Bassigny, only the inclination of the upper incisor differs clearly from other Class II cases. Boileau asks for the interincisal angle and the axis of both incisors to be measured, and for a crown-root angulation to be looked for. Our mandibular plane angle article and ANB angle article give the norms in detail.
The crown-root angulation (collum angle) has been measured in the literature. On 120 lateral cephalograms, the collum angle of the upper central incisor was greatest in Class II division 2 (3.24° ± 4.69°, against about 1° in Class II division 1 and Class I), and it was larger when the lower lip covered the middle third of the incisor crown (Srinivasan et al., 2013, Orthodontics (Chic.)). The standard deviation is large: some division 2 incisors are bent, others are not, which is why it is checked case by case.
Dougherty’s classification
Boileau’s textbook uses Dougherty’s types to place a case: type X (78%) with a harmonious profile and a small discrepancy, type Y (18%) with a short face and a concave profile below the nose, type Z (4%) with a retrusive chin and a proclined lower incisor, which resembles a division 1.
Primary or secondary: two pathways
Darqué’s classification, taught in our D.U. program, separates two forms:
- Primary (hereditary): detectable from the primary dentition, powerful musculature, molar infraocclusion, small skeletal discrepancy, dominated by the low angle and anterior rotation. Peck summarized it as small teeth in large jaws. Heredity is not the whole story: the muscular matrix maintains the pattern.
- Secondary (acquired): a skeletal Class II pattern (ANB increased, SNB reduced), the lower lip on the incisal edges of the upper incisors, the tongue at their apices, and a lateral tongue posture causing molar infraocclusion.
The definitions differ between authors. Boileau defines the secondary form as the alveolar compensation of a skeletal Class II rather than as a functional disorder. The nature of the malocclusion is itself debated: "purely occlusal" for the D.U. course, which nevertheless describes a skeletal primary form; dentoskeletal for Parielle; a skeletal component with anterior rotation for Frapier. These divergences explain why two courses do not propose the same strategy.
There is also an iatrogenic division 2: retracting the upper incisors of a division 1 in the mixed dentition without torque control can create one.
The lid effect: crowding that is not real
This is the most costly diagnostic trap. The lower arch often shows incisor crowding that is only apparent: the lower incisors are trapped under the retroclined upper incisors and pushed lingually by a tonic lower lip, so they overlap. The courses call it the lid effect. Unless there is a true tooth-size to arch-size discrepancy, much of this crowding resolves when the incisors regain their position.
Three practical consequences:
- Do not read the overlap as a true discrepancy. Lingually tipped incisors shorten the measured arch and inflate the raw crowding figure.
- Serial extractions are contraindicated in Class II division 2 according to the course materials: the incisor retroclination they cause would deepen the bite.
- Run the space analysis with the target incisor position. Here, incisor repositioning is often a gain of space, not a loss, and it changes the decision. Our free space analysis tool measures the space required and available; the Steiner box (in French) shows how incisor repositioning enters the balance.
Anterior lock, function and the TMJ
The deep bite forms an anterior lock: the retroclined upper incisors hold the mandible back. Other locks to look for, according to the courses, are a deep curve of Spee, a narrow maxillary alveolar arch and mesially rotated upper first molars.
The joint is described as an area at risk, but several points are debated. The D.U. course describes a forced, retruded intercuspal position and an atypical swallow; Parielle reports that some authors contest this, and Bassigny describes normal swallowing and breathing. Ricketts, cited by Bassigny, saw a pseudo-retrognathia from incisor contacts in two thirds of cases, but forward repositioning of the mandible after the lock is released is far from constant. The prudent reading: these signs are inconsistent, and the joint examination is part of the initial records.
Differential diagnosis
Before concluding to a division 2, rule out:
- simple crowding without true retroclination of the upper incisors;
- mesial drift of the upper molars after early loss of primary molars, which gives a false Class II;
- iatrogenic retroclination from a removable appliance used to correct proclined incisors.
Treatment planning: criteria, not a recipe
Our course materials give principles and points of disagreement; the decision remains the clinician’s. Evidence from trials is absent: a Cochrane review found no randomized or controlled clinical trial of Class II division 2 treatment in children, and concluded that there is no trial evidence to recommend or discourage any type of treatment, noting that such trials are hard to run given the low prevalence (Millett et al., 2018, Cochrane Database Syst Rev). What follows is therefore teaching and clinical studies, not trial-based guidance.
Unlock first
The first objective is to release the anterior lock: the deep bite and the upper incisor inclination. According to Boileau, restoring an anterior guidance recenters and advances the mandible, and released growth continues the correction. Hence the interest of interception in the mixed dentition, which the course calls a measure of major importance.
The order between intrusion and torque correction depends on the case. With moderate retroclination, intrusion and proclination go together. With severe retroclination (Deckbiss), an intrusive force passes behind the center of resistance and increases the retroclination, so the inclination is corrected first. The sources do not put a number on "severe".
Level according to where the deep bite comes from
The D.U. course considers the dogma of intruding only the upper incisors excessive: the deep bite is usually mixed and is corrected in roughly equal parts in the upper and lower arches. Gummy smile, the position of the incisal edges relative to the occlusal plane, the curve of Spee in both arches and the freeway space tell you which arch to level. An increased freeway space points to molar infraocclusion, which lends itself to molar extrusion during growth.
Control the vertical dimension
Bassigny’s objectives sum up the approach: do not move point A back, increase or at least not reduce the vertical dimension, close the interincisal angle, and place the incisal edge relative to the lips. The rarer high-angle division 2 calls for the opposite caution: its deep bite often corrects during alignment, and the vertical must be controlled.
Points of disagreement
- Functional orthopedics: the D.U. course recommends Class II orthopedics during growth, and this is the default position in our knowledge base. Boileau finds it often unnecessary in the primary form and warns that with a small discrepancy and strong growth, the case can drift toward a skeletal Class III, especially in boys. Bassigny accepts an activator only after the retroclination is corrected. Our Twin Block article covers the device side.
- Extractions: non-extraction first is the common principle, especially in growing patients. When extractions are needed, schools differ on the pattern; upper-only extractions are a second-line option for the D.U. course and an accepted first-line indication for Boileau.
- Profile: correcting the sagittal discrepancy of a strongly forward-rotated division 2 with a large chin does not always improve the face.
Plan retention from the start
Relapse of the deep bite is a known risk. In 62 treated division 2 patients followed about 15 years out of retention, very upright incisors before treatment went with a deeper initial overbite and a tendency to return toward it, and the initial overbite was the main predictor of the postretention overbite (Kim and Little, 1999, Angle Orthod). In 30 cases followed on study models, molar correction was stable, but overcorrection of the overbite relapsed, any increase in lower intercanine width relapsed, and 30% showed unacceptable lower incisor irregularity after retention (Canut and Arias, 1999, Eur J Orthod). Both are retrospective samples, but they agree with the courses: the lip relinguals the incisors. Boileau recommends overcorrecting axes and overbite, placing the incisors relative to the stomion and retraining function; retention aims at incisor vertical stops, and retraining does not replace retention.
In practice
- Confirm the retroclination (two or four incisors) and measure the overbite; look for palatal or gingival impingement.
- Classify the form (Bassigny) and note where the deep bite sits (upper, lower, or both).
- On the ceph, measure the interincisal angle, both incisor axes, FMA and SN-GoGn, ANB and the Wits; look for a crown-root angulation.
- Place the case: primary or secondary, Dougherty type.
- Read the lower crowding with the target incisor position: apparent or real?
- Examine function and the joints: freeway space, lips, joint sounds and pain, intercuspation versus centric relation.
- List the locks (anterior, curve of Spee, transverse, molar rotation) before choosing any appliance.
- For orthopedics and extractions, note which source supports your choice and which one questions it.
Frequently asked questions
What is a Class II division 2 malocclusion?
It is a Class II molar and canine relationship with retroclined upper central incisors, sometimes all four upper incisors, and a deep bite. The retroclined incisors hide the sagittal discrepancy, so the overjet is normal or very small despite the Class II. When the incisors are proclined during treatment, the discrepancy is "unmasked", and the plan must anticipate it.
Does Class II division 2 cause TMJ problems?
It is described as a pattern at risk because of the retruded mandibular position, the anterior lock and muscle hypertonicity, but the forced mandibular position and its link with temporomandibular disorders remain debated. The joint examination belongs in the initial records, and any dysfunction present before treatment should be documented.
Should teeth be extracted in Class II division 2?
Non-extraction is the common starting principle, especially during growth, all the more because lower crowding is often only apparent. When extractions are discussed, the pattern depends on the space analysis, the amount of Class II, the profile and the remaining growth: it is a case decision.
With GS Ortho
In GS Ortho, the diagnostic studio takes the case through 12 panels, from the clinical examination and photographs to cephalometrics and the treatment plan of the same patient. AI places 29 landmarks on the cephalogram for you to check and correct before reading the interincisal angle, the divergence and the sagittal discrepancy. When a division 2 case raises questions, "Request an opinion" sends the question, with the panel attached, to a colleague or supervisor you choose; the answer stays in the record. The treatment decision stays yours. The GS Ortho interface is currently available in French.