Page 23 - Impact of implant retained overdenture treatment and speech, oromyofunction, social participation and quality of life.

tongue against or close to the teeth, alveolar ridge, palate or uvula (fig. 4)21. However, alterations in the lower jaw, especially in fully edentulous people, may also cause articulation disorders.
Additionally, clinical experience shows that dental implants placed in a resorbed maxilla are often mispositioned due to resorption of the crest in palatal direction. This may result into wide bucco-lingual volumes, causing hinderance of the tongue during speech movement. Collaert (2015) examined the use of resin removal (removal of slices of the prosthesis) in patients suffering from speech problems due to treatment with fixed dentures on implants in the maxilla. A trained SLP examined the patients before treatment, one day after insertion of the prosthesis and after 21 days of adaptation (table 1). After reduction of the volume of the premolar region of the denture, all patients returned to baseline speech or improved speech 34. Changes in thickness of the ridge and the palate of the prosthesis are also found to be an important factor in the occurrence of speech problems in patients treated with FID 34,35.
It is also possible that other problems present depending on which jaw is treated. As suggested in the research of Jacobs et al. (2001) there are especially problems with the apico-alveolar fricatives (/s/ and /z/) in fixed rehabilitation of the maxilla and fixed reconstruction in the mandibula seems to cause more problems with the plosives (/t/ and /d/) compared to the control group 25. The reason mentioned in the paper is ‘the difference in sound formation and the involvement of upper and lower teeth’. This study assessed speech function in 113 edentulous patients wearing fixed or removable dental prosthesis supported or not by oral implants. One SLP performed a standard speech and oromyofunctional examination (table 1). Although the mentioned fricatives and plosives both are alveolar sounds, there is a difference in formation. In case of the /s/ and /z/, a narrow channel is formed between the palate and the tongue to direct the air from the lungs against the upper or lower teeth to cause turbulence. The /t/ and /d/ is formed by a total block of the tongue against the maxilla to enable the airstream to escape all at once, making the typical ‘explosive’ sound.
When overviewing the studies displayed in table 1, it is clear that there is a lot of variation in the methods used to evaluate speech during dental rehabilitation. Two main strategies are used, sometimes combined. The first strategy was analysis of the spectral properties and energy distribution of the evaluated
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Introduction
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