Oral health-related quality of life changes in standard, cleft, and surgery patients after orthodontic treatment.

INTRODUCTION: The purpose of this study was to investigate the effect of orthodontic treatment on oral health-related quality of life (OHRQoL) in groups of standard patients with severe malocclusions; cleft lip, cleft palate, or cleft lip and palate patients; and orthognathic surgery patients. METHODS: The study sample consisted of 83 consecutive patients undergoing treatment at the orthodontic unit of Christchurch Hospital, Christchurch, New Zealand, divided into 3 groups: 30 adolescents with severe malocclusions; 24 adolescents with cleft lip, cleft palate, or cleft lip and palate; and 29 adults with severe skeletal discrepancies requiring both orthognathic surgery and orthodontic treatment. Each patient completed the Short Form of the Oral Health Impact Profile (OHIP-14) questionnaire before and after orthodontic treatment. RESULTS: The baseline OHIP-14 subscale scores among the 3 study groups were significantly different, with the surgery patients having nearly twice the OHIP-14 scores of the other 2 groups for nearly half of the items (P <0.05). The surgery patients experienced the greatest reduction in OHIP-14 scores (ie, improvement in OHRQoL), with the largest effect sizes reported for the psychological discomfort (+2.73) and disability (+2.65) domains. The group with clefts experienced the smallest changes in OHIP-14 scores across all 7 domains (-0.03 to +0.63). After adjusting for age and sex, the surgical patients had a significantly greater reduction in pretreatment OHIP-14 scores than did the standard and the cleft patients (P <0.01). CONCLUSIONS: The effect of orthodontic treatment on OHRQoL varies for different patient groups even after adjusting for age and sex. The greatest improvement in OHRQoL occurred in adults with a need for orthognathic surgery, whereas the least improvement seemed to occur in adolescents with cleft lip, cleft palate, or cleft lip and palate.

The effect of incremental lower lip advancement on oral pressure and EMG activity of the lower lip.

OBJECTIVES: During orthodontic arch expansion, the teeth are displaced against the perioral soft tissues. This can affect the equilibrium of forces that are thought to act on teeth, with consequent implications for long-term stability. The aim of this study was to investigate the effect of incremental lower lip advancement on intraoral pressure and electromyographic (EMG) activity of the lower lip. MATERIALS AND METHODS: Intraoral pressure and EMG activity was measured in 10 participants (2 males, 8 females; 22 years ± 7 months) as the lower lip was incrementally advanced using three custom-made vacuum-formed stents of differing labial thicknesses (0.5, 2.5, and 4.5 mm). A task paradigm including at rest recordings and maximal voluntary contraction was completed for each tray. RESULTS: Resting lip pressure generated increased as the lower lip was advanced (P < 0.001). The EMG activity of the lower lip increased significantly (P < 0.001) only once the lip was advanced from 2.5 to 4.5 mm. For the pressure recordings, the response to incremental lip advancement showed considerable individual variation. CONCLUSIONS: These findings suggest that the initial pressure increase on the lower incisors was mostly likely due to the inherent viscoelastic properties of the lower lip, while the pressure increase between the 2.5 and 4.5 mm advancement was due to increased muscle activity. Each individual also responded to lower lip advancement in a different yet subject-specific manner.

Evaluation of primary surgical outcomes in New Zealand patients with unilateral clefts of the lip and palate.

OBJECTIVE: To evaluate and compare the primary surgical outcomes of complete unilateral cleft lip and palate (UCLP) patients in two New Zealand cleft care centres. METHODS: This is a retrospective study of two providers of cleft care in New Zealand: Centre A in the North Island and Centre B in the South Island of New Zealand. Preorthodontic study models were evaluated from 28 UCLP patients from Centre A with primary surgical repairs performed between 1987-1999 and 31 UCLP patients from Centre B with primary surgical repairs performed between 1984-2000. Dental arch relationships were measured using the Goslon Yardstick. A Goslon score of 1 is considered to be an excellent outcome, whereas a score of 5 is a very poor treatment outcome. RESULTS: Intra- (Kappa: 0.84 - 0.93) and inter-examiner (Kappa: 0.63 - 0.69) reliabilities revealed good to very good agreement between examiners using the Goslon Yardstick. The mean Goslon score for Centre A was 3.5, with no cases in Group 1, five cases in Group 2 (17.9 per cent), nine cases in Group 3 (32.1 per cent), 11 cases in Group 4 (39.3 per cent) and three cases in Group 5 (10.7 per cent). The mean score for Centre B was 3.1, with one case in Group 1 (3.2 per cent), nine cases in Group 2 (29.0 per cent), eight cases in Group 3 (25.8 per cent), 11 cases in Group 4 (35.5 per cent) and two cases in Group 5 (6.5 per cent). There were no statistically significant differences between the two centres (p > 0.05). CONCLUSIONS: The outcome scores from the two cleft centres, based on historic records, were disappointing and higher than expected. It is recommended that a review of primary surgical protocols be implemented to ensure outcomes comparable with international standards. The results provide useful benchmarks for future comparisons of treatment.