Page 52 - Impact of implant retained overdenture treatment and speech, oromyofunction, social participation and quality of life.

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Chapter 2
the pronunciation. A sound was considered present in the inventory (both the correct production and the disturbed production) when at least two instances of the production were found. The whole protocol was video-recorded and evaluated independently by two speech-language pathologists (E.F. and L.B.). One SLP (L.B.) was blinded for the stage of the treatment. Inter-rater reliability was evaluated according to Landis and Koch and is displayed in table 1.29
Additionally we performed a spectral analysis on the /s/ sound in word- initial, word-medial and word-final position. The signals were sampled at 44 100 Hz. A Samson CO1U-USB microphone was used to record the samples. Each sample was visualized by means of Praat software.30 By average a 0.1 s section was manually extracted from each /s/ token using a Hamming window. A Praat script, developed by Corthals (2008) was used to derive the four spectral moments (i.e., mean, standard deviation, skewness, kurtosis) and the peak frequency value of the Fast Fourier spectrum. We compared all spectral moments between the stages of the treatment, using Wilcoxon matched-pairs signed-rank-test.
Oromyofunctional behavior
To assess difficulties in muscle movement of the face and oral cavity, patients were asked to follow a series of instructions given by the SLP (E.F.) and perform certain movements with the facial and oral muscles. No visual modelling was performed by the SLP and there was no mirror provided to help the patients with the positioning of their muscles. The evaluation included jaw movement (in rest, open, horizontal movement of the jaw), tongue movement (tongue protrusion, tongue retrieval, tongue lift against the upper lip, tongue against the lower lip, tongue against the lip angles (left and right) and clicking the tongue against the palate), lip movement (in rest, lip closure, spread of the angles of the lips and lip protrusion) and integrated movements (coughing, blowing, spontaneous movement of the facial muscles, whistling, filling the cheeks with air, and swallowing water). The protocol of Lembrechts et al. 1999 31 was adjusted to evaluate the functions, relevant to this study population (e.g. the evaluation of the velopharyngeal function was omitted). The whole protocol was video-recorded and evaluated independently by two SLPs (E.F. and L.Br). One SLP (L.Br.) was blinded for the stage of the treatment. A task was classified to be normal or disturbed. Interrater reliability is displayed in table 4.