Presentation on theme: "The Prosthodontics is a part of the dental science that improve the esthetic and functional aspects of the oral and maxillofacial region through artificial."— Presentation transcript:
The Prosthodontics is a part of the dental science that improve the esthetic and functional aspects of the oral and maxillofacial region through artificial restoration of the lost teeth and adjacent soft tissues
Complete denture Prosthodontics The part that restore all the natural teeth and related tissue artificially
Removable partial denture Prosthodontics The part that restore one or more absent teeth and soft tissue through removable prosthesis
Fixed Prosthodontics The part that restore one or more absent teeth through fixed prosthesis
Dentulous – Full complement of teeth. Edentulous – Lost all the teeth Partially edentulous – Lost a few teeth
Surfaces of teeth – Mesial Distal Buccal Lingual Occlusal
Vertical movement Opening Closing Horizontal movement Protrusive or forward Retrusive or Backward Right lateral Left lateral
All these movements together will anable mastication
Occlusion - What is occlusion? Occlude means to close
Any contact between the incising or masticatory surfaces of the maxillary and mandibular teeth is termed as occlusion
Occlusal Plane -Average plane established by incisal and occlusal surfaces of the teeth
Curve of spee – seen in Natural dentition. Anatomic curvature of occlusal surfaces of teeth beginning at the tip of the lower canine and following the buccal cusps of the premolars and the molars, continuing to the anterior border of the Ramus,
Curve of Wilson: It is the mediolateral curve that contacts the buccal and lingual cusp tips on each side of the arch. It results from the inward incination of the posterior teeth ( mandibular molars ), making the lingual cusps lower than the buccal cusps.
Centric Occlusion – the occlusion the patient makes when they fit their teeth together in maximum intercuspation - A cusp to fossa relation.
The masticatory (or stomatognathic) system is generally considered to be made up of three parts: the Teeth, the Periodontal Tissues, and the Articulatory System.
Key of occlusion First key, Molar inter-arch relationship, the upper first molar's mesio-buccal cusp should essentially occlude into the buccal groove, of the lower first molar. The first upper molar's mesio-palatal cusp must occlude into the central fossa of lower first molar
Second key The mesial slope of the maxillary canine is in line with the distal slope of the mandibular canine.
When the maxillary and mandibular teeth contact simultaneously the condylar proceses are fully seated in the mandibular fossae
MAXILLARY AND MANDIBULAR TEETH SHOULD CONTACT EVENLY TO ALLOW OPTIMUM FUNCTION, TO MINIMIZE TRAUMA TO THE SUPPORTING STRUCTURES, AND TO ALLOW AN EVEN LOAD DISTRIBUTION THROUGHOUT THE DENTITION.
OCCLUSAL INTERFERENCES Interferences are undesirable occlusal contacts that may produce mandibular deviation during closure to maximum intercuspation.
When there is occlusal interferences there is trauma which cause tissue changes in periodontal ligament space
CENTRIC RELATION CENTRIC RELATION IS DEFINED AS THE MAXILLOMANDIBULAR RELATIONSHIP IN WHICH THE CONDYLES ARTICULATE WITH THE THINNEST AVASCULAR PORTION OF THEIR RESPECTIVE DISKS WITH THE CONDYLES IN THE ANTEROSUPERIOR POSITION AGAINST THE SHAPES OF THE ARTICULAR EMINENCES. THIS POSITION IS INDEPENDENT OF TOOTH CONTACT.
The masticatory movements takesplace with in the following movements
Opening Closing Protrusive or forward Retrusive or Backward Right lateral Left lateral All these movements together will anable mastication
Types of condylar Movements During opening or closing of the mandible Rotational movement Translational movement
Rotational Movement Around the horizontal axis (hinge axis) Around the horizontal axis (hinge axis) Opening of the jaw
Translational movement Wide opening
Translational movement Retrusive Protrusive
Movement around the vertical axis
Border movements of the Mandible in Sagittal plane
Left lateral border Left lateral border Right lateral border Right lateral border Functional movements Functional movements Border Movement of the Mandible Horizontal Plane and Frontal plane Border Movement of the Mandible Horizontal Plane and Frontal plane
Movement in the frontal plane
Movement in the saggital plane
Movement in the horizontal plane
It is with in this boundary that all the movements of the mandible and the movements of Mastication takes place.
This Masticatory system is disturbed in patients with occlusal interference.
Canine guided occlusion – During lateral excursive movement the canine contacts each other only and no other posterior teeth contact is seen,
Group function - During lateral excursive movement the canine contacts each other as well as other posterior teeth contact is seen.
Christensen's Phenomenon During protrusive movements, there will be no contact of the posterior teeth
It is important to be familiar with Definitions Components of the masticatory system Occlusal interference Key of occlusion Mandibular Movements Occlusal scheme in Natural dentition.