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Оглавление1 Terminology
It is important we address terminology right at the start to reduce the confusion that has been created throughout the history of occlusion. As a source, we will use the Glossary of Prosthodontic Terms (GTP) (2017) edition for the most part.
The three most important terms are defined below.
Centric occlusion (CO) – the occlusion of opposing teeth when the mandible is in centric relation (CR); this may or may not coincide with the maximal intercuspal position (MICP) (GTP 2017). Throughout the literature (Jiménez‐Silva et al. 2017, McNamara et al. 1995, Shildkraut et al. 1994, Weffort and de Fantini 2010), centric occlusion is also known as intercuspal or MICP and hence the confusion because the same term can indicate two different positions. So, to prevent further confusion, we will state that centric occlusion is MICP.
Centric relation – this position has five main points:
1 a maxillomandibular relationship, independent of tooth contact
2 the condyles articulate in the anterior–superior position against the posterior slopes of the articular eminences
3 the mandible is restricted to a purely rotary movement
4 from this unstrained, physiological, maxillomandibular relationship, the patient can make vertical, lateral, or protrusive movements
5 it is a clinically useful, repeatable reference position.
Each statement can be debated and to achieve consensus may be difficult, but the key point is that this is a tooth‐independent position, i.e. it can be recorded in edentulous patients. We feel that first statement is incomplete, and would add: a maxillomandibular relationship, independent of tooth contact at the correct occlusal vertical dimension (OVD) for that individual.
Centric relation contact position (CRCP) – the occlusion of opposing teeth when the mandible is in centric relation; this may or may not coincide with the MICP (GTP 2017). This may involve one pair of teeth or several pairs or may coincide with all the teeth meeting. When the teeth touch then they slide from that position into MICP. According to Posselt (1952), 90% of the population have a discrepancy between both positions.
Other important terms are given in the table below and will be defined throughout the book and in the Glossary.
| Term | Other names in the literature | Terms we will use in the book |
| Centric occlusion | Maximal intercuspal position, intercuspal position | Centric occlusion (CO)/intercuspal position (ICP)/maximal intercuspal position (MICP) |
| Centric relation | Terminal hinge axis or retruded axis position | Centric relation (CR) |
| Centric relation contact position (CRCP) | Retruded contact position, centric occlusion | Centric relation contact position (CRCP) |
| Maximal intercuspal position | Centric occlusion, intercuspal position, habitual occlusion, bite of convenience | Centric occlusion (CO)/intercuspal position (ICP) |
| Occlusal vertical dimension (OVD) | Vertical dimension of occlusion (VDO), dimension of vertical occlusion (DVO) | Occlusal vertical dimension (OVD) |
| Rest vertical dimension (RVD) | Rest position, physiological rest position, vertical dimension of rest | Rest vertical dimension (RVD) |
| Freeway space | Interocclusal distance | Interocclusal distance |
| Bennett angle | Progressive side shift | Bennett angle |
| Bennett shift (movement) | Immediate side shift | Bennett shift (movement) |
| Working side movement | Laterotrusive, laterotrusion | Working side movement |
| Non‐working side movement | Mediotrusive, Mediotrusion | Non‐working side movement |
References
1 (2017). The Glossary of Prosthodontic Terms: ninth edition. J. Prosthet. Dent. 117: e1–e105.
2 Jiménez‐Silva, A., Tobar‐Reyes, J., Vivanco‐Coke, S. et al. (2017). Centric relation–intercuspal position discrepancy and its relationship with temporomandibular disorders. A systematic review. Acta Odontol. Scand. 75 (7): 463–474.
3 McNamara, J.A., Seligman, D.A., and Okeson, J.P. (1995). Occlusion, orthodontic treatment, and temporomandibular disorders: a review. J. Orofac. Pain 9: 73–90.
4 Posselt, U. (1952). Studies in the mobility of the human mandible. Acta Odontol. Scand. 10 (Suppl 10): 19–160.
5 Shildkraut, M., Wood, D.P., and Hunter, W.S. (1994). The CR‐CO discrepancy and its effect on cephalometric measurements. Angle Orthod. 64: 333–342.
6 Weffort, S.Y.K. and de Fantini, S.M. (2010). Condylar displacement between centric relation and maximum intercuspation in symptomatic and asymptomatic individuals. Angle Orthod. 80: 835–842.
