International Dental & Medical Journal of Advanced Research ● Vol. 3 ● 2017 1 International Dental & Medical Journal of Advanced Research (2017), 3, 1–7 ORIGINAL ARTICLE Effect of single impression technique versus split cast impression technique on speech outcome in maxillary obturators - A randomized clinical trial Doaa M. Elkady 1 , Cecile G. Michael 1 , Ahmed E. Fayyad 1 , Heba M. Farag 2 , Hisham El Sebai 3 1 Department of Prosthodontics, Faculty of Oral and Dental Medicine, Cairo University, Egypt, 2 Department of ENT, Faculty of Medicine, Cairo University, Egypt, 3 Department of Surgical Oncology, National Cancer Institute, Cairo University, Egypt Abstract Background: e main problem in patients who undergone maxillectomy is the impairment of speech particularly those with hard and soſt palatal resection. e defect of the soſt palate results in velopharyngeal insufficiency. Aim: is study was conducted to evaluate the effect of using single impression technique versus split cast impression technique for maxillary obturator construction on the speech outcome using spectrogram, nasometer, and patient satisfaction questionnaire. Materials and Methods: Six patients with unilateral hard and soſt palatal defects were selected and randomly distributed into two equal groups: For group I, the patients received first definitive skeleton obturator constructed according to the single impression technique and speech outcome, and patient satisfaction outcomes were recorded. e prosthesis was then taken off from the patient for another 1 week, the obturator bulb was modified with split cast impression technique, and the same records were reported. However, in the second group, the steps were reversed that is to say split cast impression technique started first then changed into single impression technique. Results: A statistically significant increase in speech outcome and patient satisfaction outcomes was observed with the use of the definitive obturator constructed with the split cast impression technique as compared to the single impression technique. Conclusion: e use of the split cast impression technique significantly improved the speech and patient satisfaction outcomes. Clinical Significance: Split cast impression technique for maxillary obturator construction improved an intimate contact between the obturator bulb with the posterior and lateral pharyngeal walls, and hence, improved the speech and patient satisfaction outcomes. Keywords Hard and soft palatal defects, impression techniques, maxillary obturators, patient satisfaction and speech Correspondence Doaa M. Elkady. Department of Prosthodontics, Faculty of dentistry, Cairo University, Egypt. Email: D_elkady@ hotmail.com Received: 23 August 2017; Accepted: 28 September 2017 doi: 10.15713/ins.idmjar.74 Introduction e soſt palate together with the lateral and posterior pharyngeal walls creates a three-dimensional muscular valve known as velopharyngeal sphincter which are important for intimate velopharyngeal closure. [1] e complete velopharyngeal closure is required during swallowing and for production of most of speech sounds except for the nasal consonants where the velopharyngeal part remains open to allow for sound transmission into the nasal cavity, which is the primary resonating chamber for these sounds. [2] e term velopharyngeal dysfunction is referred to any alteration in the velopharyngeal mechanism, resulting from lack of tissues for achievement of proper velopharyngeal closure (velopharyngeal insufficiency), lack of neuromuscular competence in the movement of velopharyngeal structures (velopharyngeal incompetence), or as a consequence of mislearning or maladaptive velopharyngeal function not related to physical or neuromuscular problems. [3] Velopharyngeal insufficiency manifested primarily as airflow escape and hypernasality which can be distinguished by speech and nasal resonance abnormalities, while secondary effects are disorders in speech articulation. [4] Prosthetic management of velopharyngeal insufficiency is carried out by means of a pharyngeal obturator. [5] A pharyngeal obturator is a removable maxillary prosthesis used to restore the soſt palatal defect consisting of a partial or complete denture base and has a posterior extension to separate the