Page 22 - Impact of implant retained overdenture treatment and speech, oromyofunction, social participation and quality of life.

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Chapter 1
Fig 4. Sagittal view on the oral cavity with contact spots of the tongue (1) to the palate (2) with normal dentition (left), conventional denture (middle) and overdenture on MDI (right) 22.
/r/) and labiodental sounds (/v/ and /f/)11,24–29. Adaptation time is the time a patient needs to get used to their new oral situation. Because of the changes made in the oral environment during dental treatment the delicate interaction between the articulators, when producing speech sounds is being challenged. It is still unclear what the best adaptation period is for patients to get used to their new oral situation and what patient characteristics (e.g. age, gender, profession, language,...) may influence this adaptation. The adaptation time per study is displayed in table 1.
The most frequently heard complaint in dental rehabilitation is the occurrence of /s/ sound disorders 11,24,26,30,31. The /s/ sound is produced by the formation of a channel between the tongue and the palate ending in a narrow point between the tongue and the alveolar ridge, through which air is forced. The tongue makes contact with the alveolar ridge of the upper jaw in the (pre)molar region, making the specific /s/ sound. There are two ways of placing the tongue when producing the /s/ sound. A speaker can lift the apex of the tongue in the direction of the upper frontal teeth (apical production) or position the apex of the tongue against the lower frontal teeth and the blade of the tongue in the direction of the upper frontal teeth (laminal production). Icht & Ben-David (2018) found the prevalence of apical and laminal production of the /s/ and /z/ sound in 242 Hebrew-speaking adults to be respectively 40% and 60%. They detected no acoustical differences between apical and laminal productions of these sounds 32. The angle of the frontal teeth and the width of the prosthesis are especially important factors, influencing this sound 33–36. In general, research focused on the influence of rehabilitation in the upper jaw on articulation 25–27,29, as most speech sounds are formed by making an upper movement with the