Nasalance Scores as a Function of Skeletal Malocclusion of English-Speaking Adults in the North Indian Population.

OBJECTIVE: The objective of this study is quantitative assessment of nasalance for skeletal Class I (normative values), Class II, and III malocclusion in the English language for the North Indian population and to compare the normative values with the nasalance scores obtained from individuals with skeletal Class II and III malocclusion and to evaluate the normative values as a function of gender. MATERIAL AND METHODS: The study was conducted on a total sample of 200 patients with 100, 50, and 50 in group 1 (control group, Skeletal Class I), group 2 (Skeletal Class II), and group 3 (Skeletal Class III), respectively. ANB angle (anteroposterior angle formed by point A, nasion, and point B) measured on lateral cephalogram was used to categorize the patients into 3 groups. The normative nasalance scores were compared for males and females in the control group. The nasalance scores of skeletal Class II and III subjects were compared to the combined normative scores of the control group. The NasalView was used for the objective assessment of nasalance. Oral syllables (/pa/and/pi/), nasal syllables (/ma/and/mi/), and 3 passages (Zoo passage, Rainbow passage, and Nasal sentences) were used to determine the nasalance scores. RESULTS: The intragroup comparison of nasalance scores in group 1 showed statistically significant differences for different stimuli. The gender-related comparison showed no statistically significant differences in nasalance scores. The intergroup comparison of nasalance scores for skeletal malocclusion showed no statistically significant differences for different stimuli except statistically significant lower nasalance values for nasal sentences in group 3 compared to the control group. CONCLUSION: The study concluded that the nasalance scores for nasal sentences in skeletal Class III malocclusion were significantly lower than in the control group and were not statistically significant between the 3 groups for all other stimuli.

"The impact of orthognathic surgery on articulation proficiency and speech intelligibility in skeletal Class III malocclusion: 18 months follow up".

Introduction: Orthognathic surgery results in the positional change of the maxilla and mandible that may affect speech. The present study evaluated the effect of combined maxillary advancement and mandibular setback surgery on articulation proficiency and speech intelligibility in patients with non-syndromic skeletal Class III malocclusion. Methods: In this prospective study, twenty-five patients with skeletal class III malocclusion and consecutively treated with Lefort-1 maxillary advancement and mandibular setback (BSSO) orthognathic surgery were included in this study. The speech sample was recorded with a digital audio tape recorder one day before surgery and at 3, 6, 9, 12 and 18 months after surgery. Three qualified and experienced speech and language pathologists evaluated articulation errors and intelligibility of speech samples. Repeated One-way analysis of variance was used to compare articulation proficiency and speech intelligibility at different time intervals. Results: The substitution, omission, distortion and addition errors showed no significant changes at 3 months and 6 months. The total articulation errors decreased to zero at 9 months and no significant increase was observed till 18 months (P < 0.05). Speech intelligibility showed statistically non-significant improvement at any time interval. Cephalometric skeletal parameters SNA and N l A°. were significantly correlated with addition and total articulation errors at 18 months follow up. Conclusions: The ortho-surgical treatment improves speech (decreases. articulation errors) in most of the patients usually 6-9 months post-surgery. Speech intelligibility is not affected by bimaxillary orthognathic surgery in skeletal class III patients. The articulation errors were correlated to changes in position of maxilla.