Biomaterial Database

Masticatory efficiency and muscular activity in removable partial dental prostheses with different cusp angles. 2017

Mohammed Assayed Mousa, and Santosh Patil, and Edward Lynch

Lecturer, Department of Prosthodontics, College of Dentistry, Aljouf University, Sakakah, Saudi Arabia. Electronic address: dr.mohammed.assayed@gmail.com.

BACKGROUND The loss of posterior teeth has a negative effect on the masticatory efficiency and activity of mastication muscles. How these muscles are affected by partial removable dental prostheses (PRDPs) with different cusp angles is unknown. OBJECTIVE The purpose of this clinical study was to evaluate the influence of different cusp angles, with anatomic (33 degrees), semianatomic (20 degrees), and nonanatomic teeth (0 degree), on the masticatory efficiency and muscular activity of participants receiving mandibular bilateral distal PRDPs. METHODS Fifteen participants consented to the evaluation of masticatory efficiency and electromyographic (EMG) activity with a PRDP with a unified bilateral design. The cusp angles of the artificial teeth were randomly changed from anatomic (33 degrees), semianatomic (20 degrees), and nonanatomic teeth (0 degree). Masticatory efficiency was evaluated by recording 5 parameters, including number of strokes, and time of mastication while the EMG activities of the masseter and temporalis muscles, measured using surface electromyography. The data were analyzed with 1-way ANOVA and the Tukey multiple post hoc test with statistical software (α=.05). RESULTS With regard to masticatory efficiency, PRDPs with anatomic and semianatomic teeth exhibited higher masticatory efficiency than those with nonanatomic teeth, whereas no significant differences were found between PRDPs with anatomic and semianatomic teeth. With respect to EMG activity, the least EMG activity was observed in PRDPs with anatomic teeth, whereas the highest activity was observed with nonanatomic teeth. No significant differences were found between the effect of PRDPs with anatomic and semianatomic teeth on masseter activity. CONCLUSIONS Changing the cusp angle from 33 to 20 degrees in PRDPs did not influence the masticatory efficiency or the EMG activity of the masseters. However, it did lead to increased EMG activities of the temporalis muscle. PRDPs with nonanatomic teeth were associated with a significant decrease in masticatory efficiency accompanied by a significant increase in EMG activity.

UI	MeSH Term	Description	Entries
D008409	Mastication	The act and process of chewing and grinding food in the mouth.	Chewing
D008410	Masticatory Muscles	Muscles arising in the zygomatic arch that close the jaw. Their nerve supply is masseteric from the mandibular division of the trigeminal nerve. (From Stedman, 25th ed)	Masticatory Muscle,Muscle, Masticatory,Muscles, Masticatory
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D003766	Dental Occlusion	The relationship of all the components of the masticatory system in normal function. It has special reference to the position and contact of the maxillary and mandibular teeth for the highest efficiency during the excursive movements of the jaw that are essential for mastication. (From Jablonski, Dictionary of Dentistry, 1992, p556, p472)	Canine Guidance,Occlusal Guidance,Occlusal Plane,Occlusion, Dental,Dental Occlusions,Guidance, Canine,Guidance, Occlusal,Occlusal Guidances,Occlusal Planes,Occlusions, Dental,Plane, Occlusal,Planes, Occlusal
D003832	Denture, Partial, Removable	A partial denture designed and constructed to be removed readily from the mouth.	Removable Partial Denture,Denture, Removable Partial,Dentures, Removable Partial,Partial Denture, Removable,Partial Dentures, Removable,Removable Partial Dentures
D004576	Electromyography	Recording of the changes in electric potential of muscle by means of surface or needle electrodes.	Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies
D005502	Food	Substances taken in by the body to provide nourishment.	Foods
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D055815	Young Adult	A person between 19 and 24 years of age.	Adult, Young,Adults, Young,Young Adults