title: Occlusion of artificial teeth in partial dentures in the "chewing center"--first exploratory population-based evaluations.
abstract: Occlusal performance is a substantial determinant of the quality of dental prosthetic restorations. In the follow-up (SHIP 1) to the Study of Health in Pomerania (SHIP), a representative population of 3300 subjects was studied in the first exploratory evaluation of the occlusion of artificial teeth in the chewing center (first molar region) of partial dentures. A digital analysis of interocclusal records of habitual intercuspation position (ICP) was performed using the Greifswald Digital Analyzing System (GEDAS), a software package that identifies contact points as transparent areas. 562 subjects (280 men aged 61.7 ± 11.9 years and 282 women aged 60.7 ± 10.7 years) had maxillary removable partial dentures (RPDs), and 619 (271 men aged 65.0 ± 11.5 years and 348 women aged 62.4 ± 10.6 years) had mandibular RPDs. Most RPDs were retained with either attachment retainers (11.7% maxilla, 11.7% mandible), cast clasps (38.4% maxilla, 40.7% mandible), telescopes with double crowns (15.7% maxilla, 19.1% mandible), or wrought wire clasps (16.4% maxilla, 8.2% mandible). Some had a combination of different retention elements. The mean number of artificial teeth was 7.8 ± 2.9 in the maxilla and 7.5 ± 3.0 in the mandible. Only the artificial teeth (first molars) in mandibular partial dentures showed differences in the frequency of occlusal contacts between groups (chi-square test). Of these, telescopic crown-retained RPDs had the highest frequency of occlusal contacts (74.4% at tooth 36 and 77.1% at tooth 46), and wrought wire-retained RPDs had the lowest (48.4% at tooth 36 and 45.2% at tooth 46). The results for RPDs with a free-end saddle were comparable and analogous; contact frequencies for those with an interdental saddle did not differ significantly. Notably, the overall frequency of occlusal contacts was greater for tooth 46 (62.9%) than for tooth 36. In conclusion, when replacing teeth in the chewing center, particularly in the mandible, telescopic crown-retained RPDs offer a distinct advantage in terms of occlusal contacts and thus provide better occlusal stability.
authors.affiliation: Heinrich-Heine-Universität Düsseldorf. kordass@uni-greifswald.de
authors.forename: B
authors.initials: B
authors.lastname: Kordass
authors.forename: S
authors.initials: S
authors.lastname: Ruge
authors.forename: A
authors.initials: A
authors.lastname: Quooss
authors.forename: A
authors.initials: A
authors.lastname: Hugger
authors.forename: T
authors.initials: T
authors.lastname: Mundt
mesh_terms: D000368:Aged; D003442:Crowns / Q000706:statistics & numerical data; D016734:Dental Clasps / Q000706:statistics & numerical data; D003766:Dental Occlusion; D003779:Denture Design / Q000706:statistics & numerical data; D003834:Denture Precision Attachment / Q000706:statistics & numerical data; D003781:Denture Retention / Q000295:instrumentation; D003828:Denture, Overlay / Q000706:statistics & numerical data; D003832:Denture, Partial, Removable / Q000706:statistics & numerical data; D005260:Female; D005858:Germany; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007574:Jaw Relation Record / Q000379:methods; D008297:Male; D008334:Mandible; D008409:Mastication / Q000502:physiology; D008437:Maxilla; D008875:Middle Aged; D008963:Molar; D011159:Population Surveillance; D014093:Tooth, Artificial