Monobloc distraction osteogenesis results in good aesthetic and functional outcomes. The relatively high rate of complications remains a concern, and further adaptations of technique are needed to reduce the risks of this procedure.

Objective : To undertake a critical and systematic review of the literature on the impact of maxillary advancement on speech outcomes in order to identify current best evidence. Design and Main Outcome Measures : The following databases were searched: PubMed, CINAHL, and The Cochrane Controlled Trials Register. In addition, reference lists were hand searched for additional articles. Using a predefined framework and set criteria, evidence was evaluated using the assignment of levels of evidence (at least Level III on the evidence hierarchy), calculation of post-hoc power (≥ 0.8), effect size (Cohen's d ≥ 0.5), and adaptation of the parameters as set out by The Cochrane Collaboration. Results : Of the 40 studies identified, the majority (68%) fell within Level III.ii, representing cohort-type studies and a fifth (20%) within Level IV, the weakest form of evidence. Power and effect size calculations were only possible in 9 studies for different speech outcomes, and only seven studies met the set criteria for best evidence. Accordingly, current best evidence for articulation exists only for a noncleft population, is conflicting for resonance and nasalance, and is mixed for velopharyngeal function depending on which instrumental measure is used. Conclusions : There is an obvious need for further prospective research in the field with strong speech methodology such as the undertaking of interrater and intrarater reliability, adequate follow-up, and sufficient sample sizes based on a priori power analyses. Methodologic issues are discussed and recommendations made.

Background: Abnormal facial growth is a well-known sequelae of cleft lip and palate (CLP) resulting in maxillary retrusion and a class III malocclusion. In 10-50% of cases, surgical correction involving advancement of the maxilla typically by osteotomy methods is required and normally undertaken in adolescence when facial growth is complete. Current evidence for the impact of the surgery on velopharyngeal function is weak and mixed. Aims: The first objective of the study was to investigate the nature of the effect of maxillary osteotomy on the perceptual outcomes of velopharyngeal function in CLP. The second objective was to establish if speech changes seen early at 3 months post-operation persisted for a year after/following surgery', when it is considered that the maxilla is relatively stable. Methods & Procedures:Twenty consecutive patients with CLP undergoing maxillary osteotomy by a single surgeon were seen pre-operatively (T1), 3 months (T2) and 12 months (T3) post-operation. A non-cleft control group (NonCLP) undergoing surgery was also recruited. Speech data were collected using the Cleft Audit Protocol for Speech-Augmented (CAPS-A). A velopharyngeal composite score-summary (VPC-SUM) was derived from specific CAPS-A-rated parameters. An external CAPS-A-trained therapist, blinded to the study, rated the randomized samples and inter-rater reliability was established. Outcomes & Results:For the CLP group, hypernasality and nasal turbulence increased significantly post-operation. Planned comparisons were significant for T1-T2 only with a medium effect size. For hypernasality, the CLP group differed statistically from the NonCLP group at T2 and T3. For nasal turbulence, the CLP group differed statistically from the NonCLP group at T2. For VPC-SUM, there were statistically significant changes postoperatively between T1-T2 and T1-T3 only with medium effect sizes for the CLP group only. Conclusions & Implications:This study provides evidence that maxillary osteotomy affects patients with and without CLP differently. In patients with CLP, surgery may impact negatively on velopharyngeal function for speech and changes seen early on at 3 months post-operatively appear to persist at 12 months postoperatively. The findings in this study have implications for the speech care pathway of patients with CLP undergoing maxillary osteotomy in terms of assessment, review and management.

Objective: To investigate the effect of maxillary osteotomy on velopharyngeal function in cleft lip and palate (CLP) using instrumental measures. Design: A prospective study. Participants: A consecutive series of 20 patients with CLP undergoing maxillary osteotomy by a single surgeon were seen at 0 to 3 months presurgery (T1), 3 months (T2), and 12 months (T3) post-surgery. Interventions: Nasalance was measured on the Nasometer II 6400. For videofluoroscopy and nasendoscopy data, visual perceptual ratings, for example, palatal lift angle (PLAn), and quantitative ratiometric measurements, for example, closure ratio (CRa), were made using a validated methodology and computer software. Reliability studies were undertaken for all instrumental measures. Main Outcome Measures: Repeated measures analysis of variance (with time at 3 levels) for nasalance and each velar parameter. Planned comparisons across pairs of time points (T1-T2, T1-T3, and T2-T3) including effect sizes. Results: A significant difference over time was found for nasalance ( P = .001) and planned comparisons across pairs of time points were significant between T1 and T2 ( P = .008), T1 and T3 ( P = .002), but not between T2 and T3 ( P = .459) providing evidence that maxillary osteotomy can impact on nasalance adversely and that the changes seen are permanent and stable. There were also significant differences over time for PLAn ( P = .012) and CRa ( P = −.059) and planned comparisons for both velar parameters reflected similar findings to those of nasalance. Conclusions: Maxillary osteotomy can adversely affect velopharyngeal function in patients with CLP. The study provides evidence for a much earlier post-surgery review even as early as 3 months after surgery.