Three-dimensional evaluation of secondary alveolar bone grafting in patients with unilateral cleft lip and palate: A 2-3 year post-operative follow-up

OBJECTIVES

The present study aims to quantitatively assess secondary alveolar bone graft (SABG) resorption in unilateral cleft lip, alveolus and palate (UCLAP) patients in a 2-3 year longitudinal follow-up setting by using a validated 3D protocol. Furthermore, the potential relation of SABG resorption with maxillary canine position and a number of patient-related factors was investigated.

METHODS

UCLAP patients who underwent SABG and had good quality CBCT images at the following timepoints were included in the study: pre-operative (T0), immediate (T1), 6 months (T2) and either 1-2 years (T3) or 2-3 years (T4) post-operative. The final bone grafted region was defined on the T1 scans and refined in the registered T0 scans. The bone graft after resorption was determined by applying threshold-based segmentation on the registered T2, T3 or T4 scans within the segmented bone graft volume. The position of the canines was determined at every timepoint at the cleft and non-cleft side.

RESULTS

Forty-five UCLAP patients (mean age 9.0 ± 1.3 years) were included. In the first 6 months after SABG, 43.6% bone resorption was recorded. 2-3 years post-operative, 56% bone resorption was found if the maxillary canine was not yet erupted and 42.7% if it erupted through the graft. The vertical position of the canines was significantly higher on the cleft side at T3.

CONCLUSIONS

The present study reports significant SABG resorption over time. However, no correlation was found between SABG resorption and canine position, nor between other patient-related factors.

Maxillary canine position of patients with non-syndromic craniofacial disorder: a retrospective evaluation of panoramic radiographs

BACKGROUND

The study evaluates the position and displacement tendency of unerupted maxillary canines in orthodontic patients with non-syndromic craniofacial disorders (CD) compared to a control (C) group.

METHODS

Canine position and displacement tendency were evaluated using panoramic radiographs (PAN) examined with parameters such as sector classification (sectors 1-5) and inclination angles (α and β). The displacement tendency was defined as the positioning of the tip in sectors 1 or 2, as well as its combination with increased angles (α > 30° and β > 39°). In addition, the correlation of the tooth position and agenesis, cleft side, and sex was assessed.

RESULTS

A total of 116 pre-treatment PAN, divided into the CD group (n = 50; mean age 8.32 ± 2.27 years) and the C group (n = 66; mean age 10.80 ± 2.82 years), were evaluated in this study. The sector classification showed no displacement tendency in both groups. Inclination angles α/β showed a statistically significant higher displacement tendency (p = 0.01) of the CD group (n = 5) on the right side, compared to healthy subjects (n = 1). Male CD patients had a statistically significant higher displacement tendency on the right side (p = 0.03). A statistically significant correlation between cleft and non-cleft-side (p = 0.03) was found.

CONCLUSION

Patients with CD showed a statistically significant higher displacement tendency of the maxillary canine affected by the cleft side. The inclination angle was found to be the better predictor compared to the sector classification which should be considered in the orthodontic treatment planning.

Does absence of maxillary lateral incisor affect the status of maxillary canine before and after secondary alveolar bone grafting in patients with unilateral alveolar cleft?

Objectives

To investigate whether absence of maxillary lateral incisor (MXLI) would affect the status of maxillary canine (MXC) before and after secondary alveolar bone grafting (SABG) in patients with unilateral cleft lip and alveolus (UCLA) and unilateral cleft lip and palate (UCLP).

Materials and Methods

47 male patients with UCLA and UCLP, whose Bergland indices were type I or II after SABG, were divided into the MXLI-absence (n = 26) and MXLI-presence groups (n = 21). Using panoramic radiographs, the position, angulation, and development status of MXC on the cleft side, and the cleft width before SABG (T1) were evaluated. After full eruption of the permanent dentition (T2), the root length, root shape, and frequency of forced eruption of MXC on the cleft side were investigated. Then, statistical analysis was performed.

Results

Compared to the MXLI-presence group, the MXLI-absence group showed higher frequencies of mesial angulation of MXC at T1 (criteria: >25°; 46.2% vs 14.3%, P < .05) and dilaceration of MXC at T2 (26.9% vs 4.8%, P < .001). MXC on the cleft side showed positive correlations between horizontal position at T1 and forced eruption at T2, and between vertical position and mesial angulation at T1 and dilaceration at T2 (all P < .01).

Conclusions

In patients with UCLA and UCLP whose SABG outcome was successful, absence of MXLI on the cleft side increased only the frequencies of mesial angulation of MXC at T1 and dilaceration of MXC at T2, not frequency of forced eruption at T2.

Sella Turcica Bridging and Tooth Agenesis in Children With Unilateral Cleft Lip and Palate

AIM

To investigate differences in sella turcica size and bridging in children with unilateral cleft lip and palate (UCLP) with or without concomitant dental anomalies.

PATIENTS AND METHODS

A cross-sectional study was carried out looking at 56 children with nonsyndromic UCLP. Lateral cephalograms, taken before alveolar bone grafting, were used to assess sella turcica height, width, area, and bridging. Panoramic radiographs were used to evaluate the presence of dental anomalies in the cleft area including agenesis, supernumerary, and peg-shaped lateral incisors. Differences between sella turcica measurements in the presence or absence of dental anomalies were assessed using t tests. Differences between the prevalence of dental anomalies and sella turcica bridging were assessed using χ² and Fisher exact tests. Multinomial logistic regression was used to investigate potential associations between sella measurements and dental anomalies.

RESULTS

Twenty-six of the 56 children presented with agenesis of the cleft-side lateral incisor, while 7 had a supernumerary, and 19 had a peg-shaped lateral incisor. With regard to sella turcica bridging, 27 children had no calcification, 25 partial and 4 complete calcification. Children with agenesis of the cleft-side lateral incisor showed a shorter sella maximum height (P = .010) and a smaller area (P = .019). When looking at sella turcica bridging, 100% of children with complete calcification showed agenesis of the cleft-side lateral incisor, compared with 52% and 33% of children with partial calcification and no calcification, respectively (P = .034).

CONCLUSIONS

Children with UCLP and sella turcica bridging are more likely to present with agenesis of the cleft-side maxillary lateral incisor.

Comparison of dental outcomes in patients with nonsyndromic complete unilateral cleft lip and palate who receive secondary alveolar bone grafting before or after emergence of the permanent maxillary canine

INTRODUCTION

For patients with complete unilateral cleft lip and palate (CUCLP), secondary alveolar bone grafting (SABG) can be performed before or after the emergence of the cleft side permanent canine (pre-CE and post-CE, respectively). The controversy regarding dental outcomes related to the timing of SABG remains unsettled. The objective of this study was to evaluate dental survival and specific dental outcomes of cleft-adjacent teeth in children with CUCLP who received either pre-CE or post-CE SABG.

METHODS

The permanent maxillary canines and the central and lateral incisors of 21 pre-CE and 23 post-CE SABG subjects with nonsyndromic CUCLP and all cleft-related surgeries performed by the same surgeon were analyzed retrospectively. Intraoral radiographs and clinical chart notes were collected at age 7 years, at the time of the SABG, and approximately 4 years after the grafting. Dental survival, spontaneous canine eruption, planned prosthetic replacement, root development, and root resorption were analyzed.

RESULTS

Dental outcomes on the noncleft side were better than those on the cleft side. On the cleft side, dental survival of the cleft-adjacent teeth was not significantly different between the pre-CE and post-CE SABG groups (P >0.05). Most teeth completed root development after grafting, and the cleft side canine root development in the pre-CE SABG group appeared to accelerate after SABG. Trends showed that the pre-CE SABG group suffered less root resorption (16.28%; post-CE: 22.73%; P >0.05) and received fewer planned prosthetic replacements (14.29%; post-CE: 26.01%; P >0.05) but required a greater number of canine exposures (33.33%; post-CE: 4.55%; P = 0.02).

CONCLUSIONS

Pre-CE SABG showed better dental outcomes in patients with CUCLP, with fewer adverse dental outcomes than post-CE SABG.

Predictive factors for canine position in patients with unilateral cleft lip and palate

OBJECTIVES

The aims were to compare cleft and non-cleft canine position, to find predictive factors for canine position and to assess surgically exposed canines.

MATERIALS/METHODS

One hundred forty-eight individuals, born 1978-2005, with total unilateral cleft lip and palate (including Simonart's band <5 mm) treated in Gothenburg, were included. Canine angulation as well as vertical and horizontal position were assessed on panoramic radiographs (PAN) taken at the age of 10. Plausible predictive factors were registered from PAN, cast models and medical records. Data on spontaneous eruption or surgical exposure were available for 88 patients. Cleft- and non-cleft side was compared using paired t-test and Fisher's exact test. Multiple stepwise regression analysis and logistic regression analysis were used to detect possible predictors for cleft canine position.

RESULTS

The cleft canine angulation was 29.3 ± 13.1 degrees (mean ± standard deviation) versus 7.6 ± 8.2 degrees on the non-cleft side (p < 0.001). Cleft canines were higher positioned and located closer to the midline compared to non-cleft canines (p < 0.001). Age for both hard palate closure and bone grafting, cleft lateral agenesis as well as transposition were associated with canine position. Cleft canines that required surgical exposure (28%) had an increased angulation and were higher positioned than spontaneously erupted canines (p < 0.001).

LIMITATIONS

The shortcomings were the retrospective design and incomplete assessment of the buccal-palatal canine position on 2D images.

CONCLUSIONS/IMPLICATIONS

With increased age for bone grafting, decreased age for hard palate closure and transposition, an association with abnormal canine position was found. A rigorous monitoring of cleft canine eruption is, therefore, advocated.

A review of emerging bone tissue engineering via PEG conjugated biodegradable amphiphilic copolymers

Defects in bones can be caused by a plethora of reasons, such as trauma or illness, and in many cases, it poses challenges to the current treatment approaches for bone repair. With increasing demand of bone bioengineering in tissue transplant, there is a need to source for sustainable solutions to induce bone regeneration. Polymeric biomaterials have been identified as a promising approach due to its excellent biocompatibility and controllable biodegradability. Specifically, poly(ethylene glycol) (PEG) is one of the most commonly investigated polymer for use in bio-related application due to its bioinertness and versatility. Furthermore, the hydrophilic nature enables it to be incorporated with hydrophobic but biodegradable polymers like, polylactide (PLA) and polycaprolactone (PCL), to create an amphiphilic polymer. This article reviews the recent synthetic strategies available for the construction of PEG conjugated polymeric system, analysis of PEG influence on the material properties, and provides an overview of its application in bone engineering.