Dental Abnormalities, Bone Graft Quality, and Periodontal Conditions in Patients With Unilateral Cleft Lip and Palate at Different Phases of Orthodontic Treatment

Dental development in patients with and without unilateral cleft lip and palate (UCLP): a case control study

OBJECTIVE

To evaluate if the presence of unilateral cleft lip and palate (UCLP) causes delay in dental age and tooth development.

MATERIALS AND METHODS

Panoramic radiographs of 189 non-syndromic UCLP patients, aged from 6 to 20 years, were collected. Two measures of tooth development were examined: dental maturity scale for the seven left mandibular teeth (dental age-DA) and the degree of each tooth development (developmental score-DS). All the teeth except third molars were staged according to the Demirjian's method. The data of the cleft group were compared with a control group matched for age and gender, based on the findings observed in other 189 panoramic radiographs.

RESULTS

At all ages, DA was lower in the UCLP group, but not always significantly; the highest difference was - 1.411 for females at 13 years old and - 0.776 for males at 12 years old. DS of all teeth was significantly lower in the UCLP group, at all ages under 17 in females, and at all ages under 18 in males. In UCLP group, tooth development was more delayed in the maxilla compared with the mandible. No evidence of a slower development at the cleft side compared with the non-cleft side was highlighted.

CONCLUSIONS

Significant lower dental development was observed in UCLP patients compared with control ones by using DS and DA indexes.

CLINICAL RELEVANCE

These findings can help the clinicians in establishing a proper orthodontic and surgical diagnosis and treatment planning in UCLP patients and for forensic age estimation's purposes.

Comparison of early and conventional autogenous secondary alveolar bone graft in children with cleft lip and palate: A systematic review

PURPOSE

The literature is scarce on studies comparing secondary alveolar bone graft (SABG) performed early at approximately 5-6 years and at the conventional time at 9-11 years. This systematic literature review(SLR) aimed to compare clinical outcomes after two different timings of SABG in children with unilateral and bilateral cleft lip and palate.

METHODS

The inclusion criteria were autogenous iliac grafts and the following study designs: case control, cohort, clinical controlled trial (CCT), randomized CCT (RCCT), and previous SLRs. Ovid MEDLINE, Ovid EMBASE, Web of Science, Scopus, Cochrane, ProQuest and Google Scholar were the primary databases. Two calibrated examiners worked independently to select the articles. The MINORS evaluation method for surgical non-RCTs was used to assess for quality.

RESULTS

1,111 articles were retrieved and 19 qualified. Different clinical and radiographic outcomes such as bone level, periodontal status, canine eruption and cleft-side tooth survival were evaluated by different assessment methods such as CBCT volume, computed tomography, periodontal evaluation, panoramic, intraoral radiographs, and Bergland scale. No RCCT or meta-analysis was found. None of the studies received the ideal score, which is 16 for non-comparison studies and 24 for comparison studies.

CONCLUSION

Methodological variation, lack of standardization for initial cleft dimension and low-quality level rendered a fair comparison unfeasible. Although further studies are necessary, it can be assumed that early SABG also can be an acceptable option, but this was based on a single study with a reasonable level of evidence.

Odontological analysis of Polish children with unilateral cleft lip and palate

Tooth size, being the effect of interaction of genetic and prenatal factors, could be of importance in interpreting the multifactor causes of cleft lip/palate. Publications indicating decreased tooth parameters, no dental differences, or larger dimensions of teeth in cleft lip/palate patients. Researchers report mostly mesiodistal (MD) measurements of maxillary (affected) teeth. There is a lack of data for buccolingual (BL) diameters. Both MD and BL parameters have influence on the planning and performance of orthodontic treatment. The aim of this paper was to assess differences in mesiodistal and buccolingual tooth dimensions in Polish children with unilateral cleft lip and palate (UCLP) in comparison to patients without oral clefts. A total of 1883 permanent teeth, 1182 teeth of UCLP patients and 701 teeth of healthy participants were analyzed. Tooth diameters were performed using an orthodontic cast of dentition with a digital odontometer. The greatest anomalies were found in both maxillary canines and consisted of their reduced mesiodistal dimension and increased buccolingual dimension, resulting in a pathologically high crown shape index (BL/MD). Conclusion can be drawn that unilateral cleft lip and palate is a condition that causes morphological disturbances of varying severity in most mandibular and maxillary teeth both on the cleft and non-cleft sides.

A Comparison between Piezoelectric Devices and Conventional Rotary Instruments in Bone Harvesting in Patients with Lip and Palate Cleft: A Retrospective Study with Clinical, Radiographical, and Histological Evaluation

Introduction

Orofacial clefts are congenital malformations characterized by an incomplete shaping of structures that separate the nasal from the oral cavity and can affect the right, left, or both sides. The aim of the present study is to assess, with clinical, radiographical, and histological evaluations, the efficacy of piezoelectric devices compared to traditional rotating instruments in the bone harvesting in patients with history of cleft.

Materials and Methods

We have conducted a retrospective analysis on 20 patients with a history of orofacial clefts that were operated on from February 2014 to June 2017. The patients were divided into two groups: Group R in which bone graft was harvested using a burr and Group P in which the bone graft was obtained by a piezoelectric device. After a healing period of 8 months from the grafting procedure, clinical and radiographic evaluations were performed.

Results and Discussion

The use of the piezoelectric devices in bone harvesting allows a slight improvement in the final volume. This supports a faster integration into the receiving site.

Conclusions

The use of piezoelectric device in patients with history of orofacial cleft that needed bone graft represents a method to be taken into consideration because it has interesting advantages.

Dual embryonic origin of maxillary lateral incisors: clinical implications in patients with cleft lip and palate

Introduction:

Cleft lip and palate are craniofacial anomalies highly prevalent in the overall population. In oral clefts involving the alveolar ridge, variations of number, shape, size and position are observed in maxillary lateral incisors. The objective of this manuscript is to elucidate the embryonic origin of maxillary lateral incisors in order to understand the etiology of these variations.

Contextualization:

The hypothesis that orofacial clefts would split maxillary lateral incisor buds has been previously reported. However, recent studies showed that maxillary lateral incisors have dual embryonic origin, being partially formed by both the medial nasal process and the maxillary process. In other words, the mesial half of the lateral incisor seems to come from the medial nasal process while the distal half of the lateral incisor originates from the maxillary process. In cleft patients, these processes do not fuse, which results in different numerical and positional patterns for lateral incisors relating to the alveolar cleft. In addition to these considerations, this study proposes a nomenclature for maxillary lateral incisors in patients with cleft lip and palate, based on embryology and lateral incisors position in relation to the alveolar cleft.

Conclusion:

Embryological knowledge on the dual origin of maxillary lateral incisors and the use of a proper nomenclature for their numerical and positional variations renders appropriate communication among professionals and treatment planning easier, in addition to standardizing research analysis.

Evaluation of maxillary central incisors on the noncleft and cleft sides in patients with unilateral cleft lip and palate-Part 2: Relationship between root resorption, horizontal tooth movement, and quantity of grafted autogenous bone

OBJECTIVE

To evaluate the relationship between external apical root resorption (EARR) of the maxillary central incisors (U1), horizontal orthodontic tooth movement, and quantity of grafted bone in subjects with unilateral cleft lip and palate (UCLP) over an average duration of 8 years.

MATERIALS AND METHODS

Thirty subjects with UCLP were evaluated for EARR of U1 after edgewise treatment (T2). The teeth were classified as having no EARR, moderate EARR (combined into "no/moderate" EARR), or severe EARR. Frontal cephalometric radiographs acquired at eruption of U1 (T0), less than 6 months before secondary alveolar bone grafting (T1), and T2 were evaluated to determine the horizontal inclination (U1-axis angle) and distance of the root apex from the median line (U1-root-VL distance). On the cleft side, the quantities of grafted bone at less than 12 months postsecondary bone grafting and at T2 were evaluated using the alveolar bone graft (ABG) scale.

RESULTS

Cleft-adjacent teeth exhibited more severe EARR than did teeth on the noncleft side. The cleft side exhibited greater changes in U1-axis angle and U1-root-VL distance between T0 and T2 than did the noncleft side. On the cleft side, the ABG score at T2 in the severe EARR group was significantly lower than that in the no/moderate EARR group. These measurements were correlated with EARR grade.

CONCLUSIONS

Cleft-adjacent U1 exhibited more severe EARR than did the U1 on the noncleft side, which might be associated with orthodontic treatment-induced changes in horizontal inclination and root apex movement. On the cleft side, severity of EARR may be correlated with the success of ABG.

A cross-sectional analysis of the prevalence of tooth agenesis and structural dental anomalies in association with cleft type in non-syndromic oral cleft patients

Background

The aim of this study was to investigate the prevalence of tooth agenesis, microdontia, and tooth malformation among non-syndromic oral cleft patients and their potential association with cleft type and gender.

Methods

Intraoral records and radiographs of 154 patients (97 males and 57 females) were examined. The variables assessed were tooth agenesis, microdontia, dental malformations, and cleft types. The statistics included chi-square and Fisher’s exact tests as well as logistic regression to assess any mutual effects of gender and cleft type on the dental variables.

Results

Tooth agenesis occurred in 50% of the sample and microdontia in 18%. Non-statistically significant odds ratios for the association of gender and cleft type with tooth agenesis were obtained. Tooth agenesis was substantially higher at the unilateral right CL + P and the bilateral CL + P in quadrant 1 and at the unilateral left CL + P and bilateral CL + P in quadrant 2. It was also higher, at the isolated cleft palate (CP) in quadrants 3 and 4. These results were attributed to teeth 22 (31.8%) and 12 (21.6%) in the maxilla and to teeth 35 (6.1%) and 45 (5.4%) in the mandible. In unilateral CL + P patients, the cleft quadrant that presented tooth agenesis was associated with the side of the cleft.

Conclusions

Interdisciplinary treatment of the oral cleft patients should take into consideration the high prevalence of tooth agenesis and their association with the different cleft types. The most frequently affected teeth by cleft are by far the upper lateral incisors. Results indicate that tooth agenesis appears to be a genetically controlled anomaly related to the orofacial cleft development through various genetic links and not caused by the cleft disruptive process.

Cleft palate with/without cleft lip in French children: radiographic evaluation of prevalence, location and coexistence of dental anomalies inside and outside cleft region

INTRODUCTION

Prevalence of dental anomalies in cleft patients is higher than that in general population. The objectives of this study were to assess the prevalence of dental anomalies and their coexistence in French children with cleft and, then, to investigate the relation between the dental anomalies and the cleft type.

MATERIAL AND METHODS

Seventy-four non-syndromic cleft patients (6-16 years old) from Lille Regional University and Mondor-Chenevier Hospitals (France) were included. Clefts were classified as right/left unilateral cleft lip and palate (UCLP), bilateral cleft lip and palate (BCLP) and cleft palate (CP). Dental anomalies were investigated on panoramic radiographs and categorized as agenesis, supernumerary teeth, incisor rotations, impacted canines and shape anomalies. Prevalence and gender distribution of dental anomalies, mean number of affected teeth per patient, agenesis occurrence and location, and coexistence of dental anomalies were analysed by cleft type.

RESULTS

96.0% of patients presented at least one dental anomaly (agenesis 83.8%, incisor rotations 25.7%, shape anomalies 21.6%, impacted canines 18.9%, supernumerary teeth 8.1%). BCLP patients had a higher number of affected teeth, and left UCLP patients had a higher one compared to right UCLP patients. Distribution of inside (45.3%) and outside (54.7%) cleft region agenesis was similar. Adjacent (31.8%) and not adjacent (33.3%) combined dental anomalies were often encountered.

CONCLUSIONS

Dental anomalies were localized inside as well as outside cleft region and were often associated with each other. BCLP patients were more affected.

CLINICAL RELEVANCE

Early radiographic evaluation allows a comprehensive diagnosis of inside and outside cleft region anomalies, required for the multidisciplinary dental treatment.

Analyzing the teeth next to the alveolar cleft: Examination and treatment proposal prior to bone grafting based on three-dimensional versus two-dimensional diagnosis-A diagnostic study

PURPOSE

The objective was to evaluate the diagnostic and prognostic value of three-dimensional (3D) cone beam computed tomography (CBCT) on information about the cleft and alignment of cleft neighboring teeth.

MATERIALS AND METHODS

Panoramic X-rays, small-volume CBCTs, and study casts of 20 patients with a total of 22 alveolar clefts were analyzed prior to secondary bone grafting. Six maxillofacial surgeons and 6 orthodontists rated the following parameters: visibility of alveolar cleft expansion, position and probability of alignment of cleft neighbored teeth. Two-dimensional (2D) X-rays and casts were rated first; CBCT and casts followed at least 4 weeks later. Radiologic bone height in the region of the former alveolar cleft, as well as alignment and reasons for nonalignment of cleft neighbored teeth, were recorded 4 years later.

RESULTS

The rate of proper proposals regarding the real treatment outcome using 2D- or 3D-material did not differ statistically. Although 5%-45% of the proposals were changed when using 3D instead of 2D records, Fleiss multirater kappas showed no essential differences. Raters' profession and experience had no influence on the rate of correct proposals.

CONCLUSION

In orthodontics, small-volume CBCT may be justified only as supplement to a routine panoramic X-ray, and only in selected cases or for surgical preparation.

Radiographic Study of the Prevalence and Distribution of Hypodontia Associated with Unilateral and Bilateral Clef Lip and Palate in a Hungarian Population

Background

Cleft defects are one of the most frequent birth-deformities of the orofacial region and they are commonly associated with anomalies of the tooth structure, size, shape, formation, eruption, and tooth number. The aim of our study was to evaluate the prevalence, distribution, and potential association of combined hypodontia in cleft-affected patients with regard to all types of teeth in both jaws in the permanent dentition.

Material/Methods

This retrospective radiographic analysis included patients with various types of clefts treated orthodontically in the Department of Orofacial Orthopedics and Orthodontics at Heim Pàl Children’s Hospital, Budapest. There were 150 patients (84 males, 66 females) with non-syndromic unilateral (UCLP; n=120 patients) or bilateral (BCLP; n=30 patients) cleft formation (lip, alveolus and palate) who met the inclusion criteria. Statistical analysis was performed using the chi-square test and Fisher’s exact test (significance level p<0.05).

Results

Hypodontia was significantly more frequent in patients with cleft-sided lateral incisor (104 patients, 69%), with a total of 235 missing teeth, followed by the second premolars of the upper and lower jaw. A significant correlation of congenital missing teeth was observed in left-sided clefts between the upper and lower second premolar in the cleft area.

Conclusions

Hypodontia inside and outside the cleft area was frequently observed. This should affect the therapy plans, especially if the cleft-sided premolar is also absent. Further comprehensive research including numerous random samples is necessary for better estimating other possible associations.

Long-Term Computed Tomographic Evaluation of Alveolar Bone Formation in Patients with Unilateral Cleft Lip and Palate after Early Secondary Gingivoalveoloplasty

BACKGROUND

The goal of this study was to evaluate with a three-dimensional method the long-term quality of alveolar ossification in unilateral cleft lip and palate patients who underwent early secondary gingivoalveoloplasty according to the Milan surgical protocol.

METHODS

The sample consisted of 63 computed tomographic scans of unilateral cleft lip and palate patients in permanent dentition. The average age at the time of assessment was 15.7 years. Alveolar thickness, nasoalveolar height, nasal floor ossification, and hard palate morphology were evaluated using dental, axial, and coronal cuts on computed tomographic scans and three-dimensional models. All measurements were normalized and ratios of the affected side versus the nonaffected side were provided. Volume measurements and ratios of each hemimaxilla were added. The presence or absence of the permanent lateral incisor on the cleft side was also recorded.

RESULTS

Alveolar thickness and height were ideal or good, respectively, in 89.5 and 91.4 percent of the sample. Insufficient ossification (<25 percent) was found in three patients (5.2 percent), and only one of them (1.7 percent) presented no bone bridging. A statistically significant association was detected between the degree of alveolar ossification, the type of nasal floor ossification, and volume ratio.

CONCLUSIONS

Early secondary gingivoalveoloplasty seemed to allow an adequate ossification of both the alveolar and nasal region. Three-dimensional evaluation of the alveolar cleft ossification provided further information on alveolar bridging and allowed evaluation of the bone availability for implant placement.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Prevalence of dental anomalies in patients with cleft lip and palate

The aim of the present study was to investigate the prevalence of dental anomalies in a group of patients with cleft lip and palate (CL/P) in the northeast of Iran. Ninety-one patients referring to the Cleft Lip and Palate Clinic of Mashhad Dental School were enrolled and classified into right CL/P, left CL/P, and bilateral CL/P groups. Photographs, dental casts, and panoramic and periapical radiographs were retrieved, and dental anomalies were recorded. χ test was used to analyze the frequency of dental anomalies according to type of cleft and sex. Missing maxillary lateral incisors was the most frequent dental anomaly, which was slightly higher in the bilateral group (61.1%). There were significantly more cases of missing lateral incisors outside the cleft area in right CL/P (P = 0.015). Peg lateral incisors were observed in 33.3% of bilateral CL/P compared with 28% of right and 23.3% of left unilateral cases. The sample presented rotations of central incisors in the cleft area in 33.3% of bilateral clefts. In unilateral clefts, it occurred more frequently in the right side (48%). Sexual dimorphism appeared only for maxillary central incisor rotation in the cleft area, which showed significantly greater frequency in females (P = 0.025). Transposition of maxillary canine and first premolars was found in 5.5% of bilateral, 8% of right, and 3.3% of left unilateral clefts. The prevalence of dental anomalies in the studied sample seems to be higher than that reported in the normal population. More anomalies were observed at the cleft side. The frequency of most anomalies was not significantly different between the 2 sexes.

The prevalence of specific dental anomalies in a group of Saudi cleft lip and palate patients

Objective

The aims of this study were to investigate the prevalence and distribution of dental anomalies in a group of Saudi subjects with cleft lip and palate (CLP), to examine potential sex-based associations of these anomalies, and to compare dental anomalies in Saudi subjects with CLP with published data from other population groups.

Design

This retrospective study involved the examination of pre-treatment records obtained from three CLP centers in Riyadh, Saudi Arabia, in February and March 2010. The pre-treatment records of 184 subjects with cleft lip and palate were identified and included in this study. Pre-treatment maxillary occlusal radiographs of the cleft region, panoramic radiographs, and orthodontic study models of subjects with CLP were analyzed for dental anomalies.

Results

Orthopantomographs and occlusal radiographs may not be reliable for the accurate evaluation of root malformation anomalies. A total of 265 dental anomalies were observed in the 184 study subjects. Hypodontia was observed most commonly (66.8%), followed by microdontia (45.6%), intra-oral ectopic eruption (12.5%), supernumerary teeth (12.5%), intra-nasal ectopic eruption (3.2), and macrodontia (3.2%). No gender difference in the prevalence of these anomalies was observed.

Conclusions

Dental anomalies were common in Saudi subjects with CLP type. This will complicate the health care required for the CL/P subjects. This study was conducted to epidemiologically explore the prevalence of dental anomalies among Saudi Arabian subjects with CLP.

Comprehensive orthodontic treatment of adult patient with cleft lip and palate

The aim of the paper is to present full orthodontic treatment of an operated cleft lip adult patient. Case Report. An 18-year-old patient consulted for severe crowded teeth. He comes from a poor family. At that time he already had four operations (velum, palate, lip, and myringotomy). Treatment included maxillary expansion, tooth extraction, and fixed orthodontic, as well as kinesiology and speech therapy treatment. A multidisciplinary approach allowed us to achieve successfully an excellent result for this patient and gave him a harmonic smile and an optimal function without orthognathic surgery. Two years after treatment, occlusion remains stable.

Three-dimensional tooth crown size symmetry in cleft lip and cleft palate

OBJECTIVE

To evaluate and compare three-dimensional tooth size symmetry in the right and left sides of upper and lower dental arches in cleft lip and palate (CLP) patients and to compare it with an Angle Class I normal occlusion control group.

MATERIALS AND METHODS

Dental casts of 72 individuals with CLP (20 bilateral [BCLP], 34 unilateral left [ULCLP], and 18 unilateral right [URCLP]) and 53 individuals with Class I occlusion, all with permanent dentition, were randomly selected. Mesiodistal (MD), labiolingual (LL), and occlusogingival (OG) measurements of upper and lower teeth were recorded with a digital caliper. Descriptive statistics and paired t-test were used for statistical analysis.

RESULTS

Significant asymmetries were found between the right and left sides of the dental arches in CLP as follows: MD dimension: mandibular first premolar (ULCLP, P < .01); LL dimension: mandibular first premolar (URCLP, P < .05); OG dimension: maxillary central incisor and first premolar (ULCLP, P < .05 and P < .01, respectively), central incisor (BLCLP, P < .01), mandibular canine and first premolar (ULCLP, P < .01), and first molar (ULCLP, P < .05). Tooth crown size asymmetries were also recorded in the Class I group.

CONCLUSIONS

Significant three-dimensional tooth size asymmetries were found in CLP subjects; however, such asymmetries were also present on the Class I control group.

Mesiodistal tooth size in non-syndromic unilateral cleft lip and palate patients: a meta-analysis

OBJECTIVES

To evaluate, using meta-analysis methodology, mesiodistal tooth dimensions in non-syndromic unilateral cleft lip and palate (CLP) patients.

MATERIALS AND METHODS

A literature search was conducted using PubMed, Medline, Google Scholar Beta, EMBASE Excerpta Medica, CINAHL, Web of Science, and the Cochrane Collaboration, identifying English and non-English articles reporting on mesiodistal tooth dimensions on the cleft and non-cleft side of non-syndromic unilateral CLP patients. Additional studies were identified by searching reference lists of articles consulted. Only studies with a suitable control group were included. Two examiners independently performed the literature search and data extraction. Using meta-analysis software, data extracted from each selected study were statistically combined using the fixed-effects model. Weighted mean differences, 95 % confidence intervals, and heterogeneity were calculated for each measurement.

RESULTS

Four articles fulfilling the inclusion criteria were located and included in the meta-analysis. Maxillary incisors and first molars were found to be significantly larger on the non-cleft side while mandibular incisors and premolars were larger on the cleft side, in non-syndromic unilateral CLP patients. On the cleft side, maxillary premolars and second molars were larger in cleft than control patients while incisors were smaller, whereas all mandibular teeth were larger in cleft patients. On the non-cleft side, all maxillary teeth except for the central incisors were larger in the cleft than control patients, while all mandibular teeth were larger in the cleft patients except for lateral incisors.

CONCLUSIONS

Non-syndromic unilateral CLP patients tend to have larger posterior but smaller anterior teeth compared with the general population. Comparing sides, unilateral CLP patients tend to have smaller maxillary but larger mandibular teeth on the cleft than on the non-cleft side.

CLINICAL RELEVANCE

Given that obtaining a stable, functional, and esthetic occlusion requires a thorough evaluation of tooth size, knowledge about trends in tooth size variations in CLP patients can help with dental and orthodontic treatment planning.

Isolated soft tissue cleft lip: epidemiology and associated dental anomalies

OBJECTIVES

The aim of this investigation was to study the epidemiology of the isolated soft tissue cleft lip (ICL) population and to evaluate the dental anomalies associated with permanent dentition.

METHODS

The study included 19 children aged 9-13 years presenting ICL selected from 657 cleft lip-affected patients treated during the last 10 years in two craniofacial centers. Only 17 patients could be included for dental anomaly evaluation: Hyperdontia, Hypodontia, Gemination, Talon tooth, Microdontia, and Macrodontia. These were compared with cleft lip and palate (CLP) and cleft lip and alveolus (CLA)-affected populations and with normal populations.

RESULTS

 The prevalence of ICL was 2.8%. All types of tooth abnormalities were found to be higher and mainly significant for the cleft side of ICL compared with the normal population. On the side opposite the cleft, the prevalence of dental anomalies reduced toward the normal individuals and was not significantly different. The significant differences found between CLP, CLA, and ICL-affected populations were mostly depicted by lateral incisors and second pre-molar hypodontia.

CONCLUSIONS

Isolated cleft lip is a rare phenomenon among the spectrum of the cleft-affected population. The prevalence of the dental anomalies in ICL maintains the proportional trend according to clefting severity.

Engineered cartilage heals skull defects

INTRODUCTION

The purposes of this study were to differentiate embryonic limb bud cells into cartilage, characterize the nodules produced, and determine their ability to heal a mouse skull defect.

METHODS

Aggregated mouse limb bud cells (E12-E12.5), cultured in a bioreactor for 3 weeks, were analyzed by histology or implanted in 6 skull defects. Six controls had no implants. The mice were scanned with microcomputed tomography weekly. At 2 and 4 weeks, a mouse from each group was killed, and the defect region was prepared for histology.

RESULTS

Chondrocytes in nodules were mainly hypertrophic. About 90% of the nodules mineralized. BrdU staining showed dividing cells in the perichondrium. Microcomputed tomography scans showed increasing minerals in implanted nodules that completely filled the defect by 6 weeks; defects in the control mice were not healed by then. At 2 and 4 weeks, the control skull sections showed only a thin bony layer over the defect. At 2 weeks, bone and cartilage filled the defects with implants, and the implants were well integrated with the adjacent cortical bone. At 4 weeks, the implant had turned almost entirely into bone.

CONCLUSIONS

Cartilage differentiated in the bioreactor and facilitated healing when implanted into a defect. Engineering cartilage to replace bone is an alternative to current methods of bone grafting.

Abnormal tooth size and morphology in subjects with cleft lip and/or palate in the north of England

The aim of this study was to investigate tooth size and morphology in subjects with unilateral cleft palate (UCLP), bilateral cleft palate (BCLP), and isolated cleft palate (ICP) living in the north of England and to compare these with a control group. The measurements were undertaken retrospectively using dental study casts. To assess tooth size, the mesiodistal and buccolingual dimensions of each fully erupted permanent tooth were measured using digital Vernier callipers. The following morphological features of the teeth were assessed: upper incisor shovelling and crown form, the presence of Carabelli's tubercle on the upper molars, molar cusp number, and lower molar fissure pattern. Multilevel regression analysis was used to determine differences in tooth size, while chi-square tests and analysis of variance were used to assess differences in tooth morphology between the groups. Tooth size was reduced in all cleft groups in both jaws, with the smallest teeth being found in the ICP group. Upper lateral incisors on the cleft-affected side in UCLP and BCLP patients showed the greatest reduction in size. The upper central and lateral incisors on the cleft-affected side in the UCLP and BCLP groups were frequently hypoplastic or peg-shaped. Molar morphology in all the cleft groups was similar to that in the control group. Reduced tooth dimensions were found in both jaws in subjects with all types of clefts, suggesting a shared genetic basis. Additionally, the upper incisors were abnormal in morphology in UCLP and BCLP subjects with or without a cleft palate, suggesting shared local aetiological factors.

Tooth agenesis: from molecular genetics to molecular dentistry

Tooth agenesis may originate from either genetic or environmental factors. Genetically determined hypodontic disorders appear as isolated features or as part of a syndrome. Msx1, Pax9, and Axin2 are involved in non-syndromic hypodontia, while genes such as Shh, Pitx2, Irf6, and p63 are considered to participate in syndromic genetic disorders, which include tooth agenesis. In dentistry, artificial tooth implants represent a common solution to tooth loss problems; however, molecular dentistry offers promising solutions for the future. In this paper, the genetic and molecular bases of non-syndromic and syndromic hypodontia are reviewed, and the advantages and disadvantages of tissue engineering in the clinical treatment of tooth agenesis are discussed.

Orthodontic treatment for patients with clefts

Orthodontic strategies continue to evolve as new methods and treatment concepts more directly address the specific problems of patients who have clefts. By continual review of treatment outcomes and comparing outcomes with patients' problem lists and treatment objectives, clinicians will identify areas of treatment needing improvement and formulate hypotheses for future research.