Long-Term Treatment Outcomes of Primary Alveolar Bone Grafts for Alveolar Clefts: A Qualitative Systematic Review

Demineralized bone matrix for repair and regeneration of maxillofacial defects: A narrative review

OBJECTIVES

Demineralized bone matrix (DBM) is a well-established bone graft material widely accepted by dentists and the public for its favorable osteoconductivity and osteoinductive potential. This article aimed to provide a narrative review of the current therapeutic applications and limitations of DBM in maxillofacial bone defects.

STUDY SELECTION, DATA, AND SOURCES

Randomized controlled trials, prospective or retrospective clinical studies, case series and reports, and systematic reviews. MEDLINE, PubMed, and Google Scholar were searched using keywords.

CONCLUSIONS

Some evidence supported the therapeutic application of DBM in periodontal intrabony defects, maxillary sinus lifts, ridge preservation, ridge augmentation, alveolar cleft repair, orthognathic surgery, and other regional maxillofacial bone defects. However, the limitations of DBM should be considered when using it, including potential low immunogenicity, instability of osteoinductive potential, handling of the graft material, and patient acceptance.

CLINICAL SIGNIFICANCE

With the increasing demand for the treatment of maxillofacial bone defects, DBM is likely to play a greater role as a promising bone graft material. Safe and effective combination treatment strategies and how to maintain a stable osteoinductive potential will be the future challenges of DBM research.

Secondary Cleft Rhinoplasty

Secondary cleft rhinoplasty remains a challenging operation that requires an understanding of the aberrant anatomy in cleft lip nasal deformity as well as the ability to adapt various techniques suited to the needs of each patient. In this article, we review some of the classically described approaches in cleft rhinoplasty and different strategies to address the nasal subunits. Presurgical adjuncts, surgical interventions before facial skeletal maturity, and patient reported outcome measures are also discussed.

Alveolar Bone Grafting in Unilateral Cleft Lip and Palate: Impact of Timing on Palatal Shape

Alveolar bone grafting (ABG) is a critical surgical intervention in patients with a cleft of the alveolus, aimed at reconstructing the alveolar ridge to facilitate proper eruption, periodontal support, and alignment of adjacent permanent teeth. The optimal timing for ABG remains debated, with late secondary ABG between the ages of 9 and 11 being widely adopted. This study compared the palatal shapes of 28 children at a mean age of 9.5 years (SD = 0.7) who underwent early secondary ABG at a mean age of 2.1 years (SD = 0.6) or 33 children at a mean age of 10.8 years (SD = 1.5) who underwent late secondary ABG at a mean age of 8.6 years (SD = 1.3) to 60 non-cleft controls at a mean age of 8.6 years (SD = 1.2). The palatal shapes were captured with 239 landmarks digitized on the palate on a digital model. Utilizing geometric morphometric methods, i.e., generalized Procrustes superimpositions, principal component analysis, and permutation tests, we assessed the impact of ABG timing on palatal morphology. The first five principal components (PCs) explained 64.1% of the total shape variability: PC1 = 26.1%; PC2 = 12%; PC3 = 11.9%; PC4 = 7.8%; and PC5 = 6.4%. The Procrustes distance between both cleft groups and the control group was more than twice as large as the Procrustes distance between the early ABG and late ABG groups. Nonetheless, all intergroup differences were statistically significant. Our findings suggest that early ABG has a limited negative effect on palatal shape, providing comparable outcomes to late ABG. The study highlights the potential suitability of early ABG, challenging conventional practices and encouraging further exploration into its long-term effects on maxillary growth.

Evidence Mapping and Quality Analysis of Systematic Reviews on Various Aspects Related to Cleft Lip and Palate

BACKGROUND

Management of cleft lip and palate is interdisciplinary. An evidence-mapping approach was envisaged to highlight the existing gaps in this field, using only the highest level of evidence.

OBJECTIVES

To conduct evidence mapping and quality analysis of systematic reviews and meta-analyses related to any aspect of cleft lip and palate.

SEARCH METHODS

The cleft lip and palate field was divided into 9 domains and 50 subdomains and a method of categorization of systematic reviews was established. A comprehensive search strategy was carried out in seven databases along with the search of gray literature and references of included articles.

SELECTION CRITERIA

Systematic reviews related to any aspect of cleft lip and palate, conducted by a minimum of two reviewers, with a comprehensive search strategy and adequate quality analysis were included.

DATA COLLECTION AND ANALYSIS

A self-designed, pre-piloted data-extraction sheet was used to collect information that was analyzed through an expert group discussion. Quality analysis was performed using ROBIS-I, AMSTAR 2, and the PRISMA checklist.

RESULTS

A total of 144 systematic reviews published between 2008 and 2022 were included. The largest number of these could be categorized in the therapeutic domain (n = 58). A total of 27% of the studies were categorized as inconclusive, 40% as partially conclusive, and 33% as conclusive. As per ROBIS-I, 77% of reviews had high risk of bias while 58% were graded as critically low in quality as per AMSTAR 2. The majority of systematic reviews showed low reporting errors.

CONCLUSIONS

The majority of systematic reviews related to cleft lip and palate relate to therapeutic and prognostic domains and show high risk of bias and critically low quality regardless of the source journal. The results of this paper might serve as a starting point encouraging authors to carry out high-quality research where evidence is lacking.

REGISTRATION

A multidisciplinary expert-group formulated an a priori protocol, registered in Open Science Framework (DOI 10.17605/OSF.IO/NQDV2).

Evaluation of Dental Root Development Regarding Maxillary Canine Eruption Status after Secondary Alveolar Bone Grafting in Patients with Cleft Lip and Palate

In children born with cleft lip and palate, the timing of the secondary alveolar bone graft (SABG) is crucial to its success; this involves estimating the eruption of the permanent maxillary canine. Altered dental eruption in this patient group gives impetus to the identification of dental developmental factors concerning maxillary canine eruption, which may steer the clinical decision of SABG timing. Records of over nine hundred patients who received SABG with pre- and post-operative cone beam computed tomography (CBCT) scans were analyzed for inclusion and divided into two groups (erupting or non-erupting canine after SABG). Roots of the maxillary canines and premolars were segmented from the cementoenamel junction then linear and volumetric measurements were performed. The pre- and post-operative root length and volume differences were calculated and compared statistically using independent sample tests and paired t-tests. No statistically significant differences were found in the volume change (%), or reciprocal of mean root length in the erupted and unerupted groups in the canine, first premolar, or second premolar roots except for an association between the post-operative dental root length of the canine and the maxillary canine eruption status. Therefore, assessment of root development from pre-treatment CBCT scans was not deemed worthy from a diagnostic perspective.

Craniofacial Growth at Age 6–11 Years after One-Stage Cleft Lip and Palate Repair: A Retrospective Comparative Study with Historical Controls

Background: Primary alveolar bone grafting inhibits craniofacial growth. However, its effect on craniofacial growth in one-stage cleft lip and palate protocols is unknown. This study investigated whether primary alveolar bone grafting performed during one-stage unilateral cleft lip and palate repair negatively affects growth up to 6–11 years old. Methods: The craniofacial growth, dental arch relationship and palatal morphology at 6–11 years old in children with unilateral cleft lip and palate were compared retrospectively. Two cohorts after a one-stage protocol without (Group A) and with (Group B) primary bone grafting at the same center were compared. Further, cephalometric measurements for growth were compared with an external cohort of a one-stage protocol and a heathy control. Results: Group A comprised 16 patients assessed at 6.8 years (SD 0.83), and Group B comprised 15 patients assessed at 9 years (SD 2.0). Cephalometric measurements indicated similar sagittal maxillary growth deficits and a significant deviation in maxillary inclination in both groups compared to the healthy group. Moderate to severe changes in palatal morphology were observed in 70% of the members in both groups. Conclusion: Omitting primary alveolar bone grafting under the one-stage protocol with two-flap palatoplasty studied did not improve growth at 6–11 years. The results implicate two-flap palatoplasty with secondary healing as having greater adverse effects on growth than primary alveolar bone grafting. Dental and palatal morphology was considerably compromised regardless of primary alveolar bone grafting.

Secondary bone grafting for alveolar clefts: surgical timing, graft materials, and evaluation methods

Alveolar cleft belongs to the spectrum of cleft lip and/or palate, affecting 75% of cleft lip/palate patients. The goals of alveolar cleft treatment are stabilizing the maxillary arch, separating the nasal and oral cavities, and providing bony support for both erupting teeth and the nasal base via the piriform aperture. Secondary alveolar bone grafting is a well-established treatment option for alveolar cleft. Secondary alveolar bone grafting is performed during the period of mixed dentition using autologous bone from various donor sites. There are several issues relevant to maximizing the success of secondary alveolar bone grafting, including the surgical timing, graft material, and surgical technique. In this study, we reviewed issues related to surgical timing, graft materials, and evaluation methods in secondary alveolar bone grafting.Abbreviations: ABG, alveolar bone grafting; CBCT, cone-beam computed tomography; DBM, demineralized bone matrix; GPP, gingivoperiosteoplasty; rhBMP, recombinant human bone morphogenetic protein; 2D, two dimensional; 3D, three dimensional

Disparities in Timing of Alveolar Bone Grafting and Dental Reconstruction in Patients With Clefts

This study sought to identify disparities in the timing of alveolar bone grafting (ABG) surgery and the replacement strategy for missing maxillary lateral incisors for patients with clefts.

A retrospective record review identified patients who underwent ABG. Multivariable regression analyzed the independent contribution of each variable.

This institutional study was performed at the University of California, San Francisco.

Patients who presented under age 12 and underwent secondary ABG between 2012 and 2020 (n = 160).

The age at secondary ABG and the recommended dental replacement treatment for each patient, either dental implantation or canine substitution.

The average age at ABG was 10.8 ± 2.1 years, 106 (66.3%) patients were not White, and 80 (50.0%) had private insurance. Independent predictors of older age at ABG included an income below $ 50 000 as estimated from ZIP code (β = 15.0 months, 95% CI, 5.7-24.3, P = .002) and identifying as a race other than White (β = 10.1 months, 95% CI, 2.1-18.0, P = .01). After ABG, patients were more likely to undergo dental implantation over canine substitution if they were female (odds ratio [OR] = 4.3, 95% CI, 1.3-17.1, P = .02) or had private insurance (OR = 12.5, 95% CI, 2.2-143.2, P = .01).

Patients who were low-income or not White experienced delays in ABG, whereas dental implantation was more likely to be recommended for patients with private insurance. Understanding the sources of disparities in dental reconstruction of cleft deformities may reveal opportunities to improve equity.

Long-term follow-up of mandibular dental arch changes in patients with complete non-syndromic unilateral cleft lip, alveolus, and palate

Background

Treatment of cleft lip and palate (CLP) requires a comprehensive interdisciplinary approach and long-term follow-up. Only a few studies are available that reported on changes after treatment, which showed that in particular the transverse dimension, in patients with CLP is prone to changes after treatment. However, those studies did not pay attention to concomitant changes in the mandibular arch that occur after treatment.

Objectives

To evaluate mandibular transverse dental arch dimensions and interarch transverse changes in patients with complete non-syndromic unilateral cleft lip, alveolus, and palate (CUCLAP) up to five years after treatment.

Material and Methods

Retrospective longitudinal study in 75 consecutive patients with CUCLAP directly after comprehensive treatment (T0), two (T2), and 5 years after treatment (T5). Great Ormond Street, London and Oslo (GOSLON) scores were available for all patients. Three-dimensional scans of all dental casts were made. Inter premolar and intermolar distances between the mandibular contralateral teeth were measured. The modified Huddart Bodenham (MHB index) was applied to assess the transverse interarch relationship. Paired t-tests and ANOVA were used to analyze transverse and interarch transverse changes. Linear regression analysis was done to define contributing factors.

Results

Paired t-tests showed a significant decrease of the mandibular inter first and second premolar distances (p < 0.05) and an increase of the inter second molar distance, whilst the MHB Index deteriorated at all time points for all segments and for the total arch score (p < 0.05). Linear regression showed no significant contributing factors on the decrease of the transverse distances. However, inter arch transverse relationship was significantly affected by age at the end of treatment, missing maxillary lateral incisor space closure, and the GOSLON Yardstick score at the end of treatment (p < 0.05), especially during the first two years after treatment.

Conclusions

Changes occurred in the mandibular arch expressed as changes in the transverse dimensions and interarch relationship measured by the MHB Index. A younger age at the end of treatment, space closure for a missing maxillary lateral incisor and a higher GOSLON score at the end of treatment negatively influence the interarch transverse deterioration especially in the first two years after treatment. For the transverse dimensional changes in the mandibular arch such influencing factors could not be determined.

Maxillofacial morphology in post-pubertal patients with unilateral cleft lip and palate following early vs. late secondary alveolar bone grafting

The study aimed at comparing maxillofacial morphology and burden of surgical treatment in post-pubertal patients with unilateral cleft lip and palate (UCLP) following early vs. late secondary alveolar bone grafting (SABG). In this retrospective study maxillofacial morphology was assessed on lateral cephalograms of skeletally matured patients with UCLP operated on consecutively in one center by the same method of one-stage primary cleft repair followed by SABG. Cephalometric analysis comprised 8 angular and 7 linear measurements. Maxillary growth restriction was evaluated by measuring SNA angle and Co-A and PNS-A distances. Five linear regression models with SNA, SNB, ANB, Co-A, and MP/SN as dependent variables and age at primary cleft repair, age at SABG, age at taking cephalogram, surgeon, and total number of surgical interventions as independent variables were also created. 135 patients were included in the study - 70 patients (47 males and 23 females) had early SABG (E-SABG group) and 65 patients (40 males and 25 females) had late SABG (L-SABG group). Mean age at bone grafting procedure was 2.7 years (range 1.5-5.9, SD 1.1) and 10.3 years (range 6.1-18.8, SD 3.2) in E-SABG and LSABG group respectively. The variables describing the degree of maxillary growth restriction - SNA, Co-A, and PNS-A - were comparable in both groups (p = 0.707, 0.116, and 0.932, respectively). Regression models demonstrated that independent variables were not associated with the values of SNA angle, SNB angle, ANB angle, MP/SN angle, and Co-A distance (p = 0.761, 0.088, 0.249, 0.380, and 0.363, respectively). The percentages of oronasal fistula repair, VPI repair, repeated SABG, upper lip correction, rhinoplasty, orthognathic surgery were 22.9, 7.1, 15.7, 24.3, 42.9, 2.9 in E-SABG group and 27.7, 7.7, 9.2, 36.9, 47.7, 3.1 in L-SABG group respectively. Mean number of all surgical interventions was 3.2 in E-SABG and 3.4 in L-SABG group, respectively (p = 0.271). Considering the comparable maxillofacial morphology and burden of surgical care in matured patients after early and late SABG, the choice of timing of bone grafting surgery could be left to the discretion of the surgeon.