Nuno V. Hermann

Helmet Versus Active Repositioning for Plagiocephaly: A Three-Dimensional Analysis

BACKGROUND AND PURPOSE: Orthotic helmets and active repositioning are the most common treatments for deformational plagiocephaly (DP). Existing evidence is not sufficient to objectively inform decisions between these options. A three-dimensional (3D), whole-head asymmetry analysis was used to rigorously compare outcomes of these 2 treatment methods. PATIENTS AND METHODS: Whole-head 3D surface scans of 70 infants with DP were captured before and after treatment by using stereophotogrammetric imaging technology. Helmeted (n = 35) and nonhelmeted/actively repositioned (n = 35) infants were matched for severity of initial deformity. Surfaces were spatially registered to a symmetric template, which was deformed to achieve detailed right-to-left point correspondence for every point on the head surface. A ratiometric asymmetry value was calculated for each point relative to its contralateral counterpart. Maximum and mean asymmetry values were determined. Change in mean and maximum asymmetry with treatment was the basis for group comparison. RESULTS: The helmeted group had a larger reduction than the repositioned group in both maximum (4.0% vs 2.5%; P = .02) and mean asymmetry (0.9% vs 0.5%; P = .02). The greatest difference was localized to the occipital region. CONCLUSIONS: Whole-head 3D asymmetry analysis is capable of rigorously quantifying the relative efficacy of the 2 common treatments of DP. Orthotic helmets provide statistically superior improvement in head symmetry compared with active repositioning immediately after therapy. Additional studies are needed to (1) establish the clinical significance of these quantitative differences in outcome, (2) define what constitutes pathologic head asymmetry, and (3) determine whether superiority of orthotic treatment lasts as the child matures.

Early Craniofacial Morphology and Growth in Children With Unoperated Isolated Cleft Palate

OBJECTIVE Analysis of craniofacial morphology and growth in children with untreated isolated cleft palate (ICP) (cleft of the secondary palate only) at 2 and 22 months of age and comparison of the morphology and growth to that of a control group with unilateral incomplete cleft lip (UICL). MATERIAL AND METHODS A total of 98 cleft children (53 with ICP and 45 with UICL) drawn from a larger group representing all Danish children with cleft born in the period 1976 to 1981 were included in the study. Craniofacial morphology and growth were analyzed using three-projection infant cephalometry. RESULTS The ICP group differed significantly from the UICL group. The most striking findings in the ICP group were: short maxilla; reduced posterior maxillary height; increased posterior maxillary width (in the 2-month-old); short mandible; reduced posterior height of the mandible; bimaxillary retrognathia; and reduced pharyngeal depth, height, and area. The facial growth pattern was fairly similar in the two groups except for a somewhat more vertical growth direction in the ICP group. CONCLUSION The facial morphology in ICP children differs significantly from that of children with UICL of the same age. The differences in facial morphology can be ascribed to the difference in the primary anomaly in the ICP group. The facial growth pattern was fairly similar in the ICP and UICL group; however, a somewhat more vertical growth direction was observed in the ICP group.

Pattern of traumatic dental injuries in the permanent dentition among children, adolescents, and adults

BACKGROUND Traumatic dental injuries (TDI) comprise six types of luxation and seven types of tooth fractures. The risk of pulp necrosis is increased in teeth with combination injuries where fractures and luxations occur concomitantly. AIM To report and compare the distributions of luxations and fracture types among children, adolescents, and adults, and to analyze the distribution and prevalence of combination injuries. MATERIAL AND METHOD The study group included 4754 patients (3186 men and 1568 women) with 10 166 traumatized permanent incisors treated at Copenhagen University Hospital, Rigshospitalet. Differences in the distributions of trauma types among age groups (children <12 years, adolescents 12-20 years, and adults >20 years) and distributions of concomitant crown fractures for each luxation type were analyzed with the Chi-square test. RESULTS A total of 7464 teeth (73.4%) had suffered a luxation injury and 5914 teeth (58.2%) a fracture. The overall most frequent injuries were crown fractures without pulp exposure (34.9%), concussions (24.2%), and subluxations (22.2%). The relative frequency of crown fractures without pulp exposure decreased across age groups (children 45.2%, adolescents 36.5%, adults 26.3%, P < 0.001), whereas the relative frequencies of other injury types increased across age groups : crown-root fractures (children 1.8%, adolescents 6.3%, adults 9.2%, P < 0.001), root fractures (children 2.5%, adolescents 4.6%, adults 8.7%, P < 0.001), and lateral luxations (children 5.7%, adolescents 10.9%, adults 13.0%, P < 0.001). One-third of the traumatized teeth (n = 3212) had sustained a combination of a fracture and a luxation injury. The luxation types most frequently presenting with a concomitant crown fracture were concussion (57.9%), intrusion (47.2%), and subluxation (33.4%) (P < 0.001). CONCLUSION The majority of TDI were minor injuries. The relative frequencies of injury types varied among age groups. Combination injuries were observed in one-third of the traumatized teeth and occurred most frequently in teeth with concussion, intrusion, and subluxation.

Early postnatal development of the mandible in children with isolated cleft palate and children with nonsyndromic Robin sequence.

Objective Analysis of early postnatal mandibular size and growth velocity in children with untreated isolated cleft palate (ICP), nonsyndromic Robin sequence (RS), and a control group of children with unilateral incomplete cleft lip (UICL). Material 114 children (66 isolated cleft palate, 7 Robin sequence, 41 unilateral incomplete cleft lip) drawn from a group representing all Danish cleft children born from 1976 through 1981. All children were examined at both 2 and 22 months of age. Methods Cephalometric x-rays and maxillary plaster casts. Mandibular length and height were measured and mandibular growth velocity (mm/year) was calculated. Cleft width was measured on the casts at 2 months of age. Results Mean mandibular length and posterior height were significantly smaller in isolated cleft palate and Robin sequence, compared with unilateral incomplete cleft lip. Mandibular length in Robin sequence was also significantly shorter, compared with isolated cleft palate. No significant difference was found between mean mandibular growth velocities in the three groups. No significant correlation was found between mandibular length and cleft width in either isolated cleft palate or Robin sequence at 2 months of age. Conclusion The children with isolated cleft palate and Robin sequence had small mandibles shortly after birth, but with a relatively normal growth potential. No true mandibular catch-up growth was found up to 22 months of age in either group. No significant correlation was found between mandibular size and cleft width in either group at 2 months of age. However, there was a significant trend toward the shorter the mandible, the more severe the sagittal extension of the cleft.

Early Craniofacial Morphology and Growth in Children With Nonsyndromic Robin Sequence

PURPOSE Craniofacial morphology and growth comparisons in children with untreated nonsyndromic Robin Sequence (RS) and a control group with unilateral incomplete cleft lip (UICL) in which the lip was surgically closed at 2 months of age. MATERIAL The 52 children (7 RS and 45 UICL) included in the study were drawn from a group representing all Danish cleft children born 1976 through 1981. The ages of the children were 2 and 22 months at the time of examination 1 and 2, respectively. METHOD The method of investigation was three-projection cephalometry. Craniofacial morphology was analyzed by means of linear, angular, and area variables. Growth at a specific anatomical location in a patient was defined as the displacement vector from the coordinate of the corresponding landmark at examination 1 to its coordinate at examination 2. RESULTS The most striking findings in the RS group were markedly increased posterior maxillary width, increased width of the nasal cavity, short maxilla with reduced posterior height, short mandible, bimaxillary retrognathia, and severe reduction in size of the pharyngeal airway. The amount of facial growth was similar in the two groups; however, a tendency toward a more vertical growth direction was observed in the RS group. CONCLUSION Facial morphology in children with RS differed significantly from that of children with UICL at both 2 and 22 months of age. The magnitude of facial growth was similar in the two groups, whereas a tendency toward a more vertical facial growth direction was observed in the RS group.

Craniofacial morphology and growth comparisons in children with Robin Sequence, isolated cleft palate, and unilateral complete cleft lip and palate.

OBJECTIVE Comparison of early craniofacial morphology and growth in children with nonsyndromic Robin Sequence (RS), isolated cleft palate (ICP), and unilateral complete cleft lip and palate (UCCLP). SUBJECTS One hundred eight children with cleft: 7 with RS, 53 with ICP, and 48 with UCCLP were included in the study. The children were drawn from the group of all Danish children with cleft born 1976 through 1981. METHOD Three-projection infant cephalometry. RESULTS The craniofacial morphology in the RS, ICP, and UCCLP groups had some common characteristics: a wide maxilla with decreased length and posterior height, wide nasal cavity, short mandible, bimaxillary retrognathia, and reduced pharyngeal airway. The shortest mandible was found in RS followed by ICP and UCCLP; the pharyngeal airway was reduced in RS and ICP, compared with UCCLP; and the maxillary complex and nasal cavity were wider in UCCLP than in the other groups. The amount of facial growth in all three groups was similar; however, the direction was more vertical in UCCLP than in RS and ICP. CONCLUSION Except for a shorter RS mandible, the facial morphology of infants with RS and ICP was similar, as was the amount of facial growth and the growth pattern. The differences in facial morphology can be ascribed to the difference in the primary anomaly. The amount of facial growth was similar in the three groups; however, the growth pattern showed a more vertical direction in UCCLP than in RS and ICP. It is hypothesized that the mandibular retrognathia in RS represents the outer end of that of the ICP distribution.

Combination injuries 2. The risk of pulp necrosis in permanent teeth with subluxation injuries and concomitant crown fractures

BACKGROUND The reported risk of pulp necrosis (PN) is generally low in teeth with subluxation injuries. A concomitant crown fracture may increase the risk of PN in such teeth. AIM To analyse the influence of a concomitant trauma-related infraction, enamel-, enamel-dentin- or enamel-dentin-pulp fracture on the risk of PN in permanent teeth with subluxation injury. MATERIAL AND METHODS   The study included 404 permanent incisors with subluxation injury from 289 patients (188 male, 101 female). Of these teeth, 137 had also suffered a concomitant crown fracture. All the teeth were examined and treated according to a standardized protocol. STATISTICAL ANALYSIS   The risk of PN was analysed separately for teeth with immature and mature root development by the Kaplan-Meier method, the log-rank test and Cox regression analysis. The level of significance was set at 5%. Risk factors included in the analysis were gender, patient age, crown fracture type, mobility and response to an electric pulp test (EPT) at the initial examination. RESULTS   Teeth with immature root development: The risk of PN was increased in teeth with a concomitant enamel fracture (log-rank test: P = 0.002), enamel-dentin fracture (log-rank test: P < 0.0001), enamel-dentin-pulp fracture (log-rank test: P < 0.0001) and in teeth with no response to EPT at the initial examination [hazard ratio: 21 (95% confidence interval, CI: 2.5-172.5), P = 0.005]. Teeth with mature root development: the risk of PN was increased in teeth with an enamel-dentin fracture [hazard ratio: 12.2 (95% CI: 5.0-29.8), P < 0.0001], infraction [hazard ratio: 5.1 (95% CI: 1.2-21.4) P = 0.04] and in teeth with no response to EPT at the initial examination [hazard ratio: 8 (95% CI: 3.3-19.5), P < 0.0001]. CONCLUSION   A concomitant crown fracture and no response to EPT at the initial examination may be used to identify teeth at increased risk of PN following subluxation injury.

Combination injuries 3. The risk of pulp necrosis in permanent teeth with extrusion or lateral luxation and concomitant crown fractures without pulp exposure

AIM To analyze the influence of a crown fracture without pulp exposure on the risk of pulp necrosis (PN) in teeth with extrusion or lateral luxation. MATERIAL AND METHODS The study included 82 permanent incisors with extrusion from 78 patients (57 male, 21 female) and 179 permanent incisors with lateral luxation from 149 patients (87 male, 62 female). A total of 25 teeth with extrusion and 33 teeth with lateral luxation had suffered a concomitant crown fracture (infraction, enamel fracture or enamel-dentin-fracture). All the teeth were examined and treated according to a standardized protocol. STATISTICS The risk of PN was analyzed separately for teeth with immature and mature root development by the Kaplan-Meier method, the log-rank test and Cox regression (lateral luxation only). The level of significance was set at 5%. Risk factors included in the analysis were gender, age, crown fracture, and response to electric pulp test at the initial examination. RESULTS A concomitant crown fracture significantly increased the risk of PN in teeth with lateral luxation. For teeth with immature root development (hazard ratio: 10 [95% confidence interval (CI): 1.1-100] P = 0.04), the overall risk increased from 4.7% (95% CI: 0-10.8) to 40% (95% CI: 2.8-77.2). For teeth with mature root development [hazard ratio: 2.4 (95% CI: 1.4-4.2) P < 0.001], the overall risk increased from 65.1% (95% CI: 55.2-75.1) to 93% (95% CI: 85.5-100). In teeth with extrusion and mature root development, the overall risk of PN increased from 56.5% (95% CI: 37.7-75.4) to 76.5% (95% CI: 58.9-94) in case of a concomitant crown fracture, but the difference was not statistically significant (P > 0.05). CONCLUSION A concomitant crown fracture without pulp exposure significantly increased the risk of PN in teeth with lateral luxation. This risk factor may be used to identify teeth at increased risk of PN following lateral luxation injury.

Computational mouse atlases and their application to automatic assessment of craniofacial dysmorphology caused by the Crouzon mutation Fgfr2C342Y

Crouzon syndrome is characterized by premature fusion of sutures and synchondroses. Recently, the first mouse model of the syndrome was generated, having the mutation Cys342Tyr in Fgfr2c, equivalent to the most common human Crouzon/Pfeiffer syndrome mutation. In this study, a set of micro‐computed tomography (CT) scannings of the skulls of wild‐type mice and Crouzon mice were analysed with respect to the dysmorphology caused by Crouzon syndrome. A computational craniofacial atlas was built automatically from the set of wild‐type mouse micro‐CT volumes using (1) affine and (2) non‐rigid image registration. Subsequently, the atlas was deformed to match each subject from the two groups of mice. The accuracy of these registrations was measured by a comparison of manually placed landmarks from two different observers and automatically assessed landmarks. Both of the automatic approaches were within the interobserver accuracy for normal specimens, and the non‐rigid approach was within the interobserver accuracy for the Crouzon specimens. Four linear measurements, skull length, height and width and interorbital distance, were carried out automatically using the two different approaches. Both automatic approaches assessed the skull length, width and height accurately for both groups of mice. The non‐rigid approach measured the interorbital distance accurately for both groups while the affine approach failed to assess this parameter for both groups. Using the full capability of the non‐rigid approach, local displacements obtained when registering the non‐rigid wild‐type atlas to a non‐rigid Crouzon mouse atlas were determined on the surface of the wild‐type atlas. This revealed a 0.6‐mm bending in the nasal region and a 0.8‐mm shortening of the zygoma, which are similar to characteristics previously reported in humans. The most striking finding of this analysis was an angulation of approximately 0.6 mm of the cranial base, which has not been reported in humans. Comparing the two different methodologies, it is concluded that the non‐rigid approach is the best way to assess linear skull parameters automatically. Furthermore, the non‐rigid approach is essential when it comes to analysing local, non‐linear shape differences.

Periodontal healing complications following extrusive and lateral luxation in the permanent dentition: a longitudinal cohort study

PURPOSE To analyze the risk of tooth loss and complications in periodontal ligament (PDL) healing following extrusive and lateral luxation in the permanent dentition. MATERIALS AND METHODS Eighty-two permanent teeth (78 patients) with extrusive luxation and 179 teeth (149 patients) with lateral luxation were included in the study. All teeth were examined according to a standardized protocol including clinical, photographic, and radiographic registration. Follow-up controls were performed at regular intervals (3, 6 weeks, 6 months, 1, 5, and 10 years). STATISTICS The risk of repair-related resorption (surface resorption), infection-related resorption (inflammatory resorption), ankylosis-related resorption (replacement resorption), marginal bone loss, and tooth loss was analyzed with the Kaplan-Meier method. Differences among subgroups were analyzed with log-rank test and Cox regression. RESULTS The risk of periodontal healing complications was estimated after 3 years. Extrusive luxation: For immature root development, infection-related resorption was 2.4% (95% confidence interval (CI): 0-6.9%). For mature root development, repair-related resorption was 15.6% (95% CI: 4.4-26.7%), infection-related resorption was 5.1% (95% CI: 0-11.7%), and marginal bone loss was 17.5% (95% CI: 6.2-28.8%). No teeth showed ankylosis-related resorption, and no teeth were lost in the observation period. Lateral luxation: For immature root development, repair-related resorption was 2.1% (95% CI: 0-6.1%), infection-related resorption was 2.1% (95% CI: 0-6.1%). For mature root development, repair-related resorption was 29.5% (95% CI: 20.5-38.5%), infection-related resorption was 2.6% (95% CI: 0-6.4%), ankylosis-related resorption was 0.8% (95% CI: 0-2.3%), marginal bone loss was 6.9% (95% CI: 2.2-11.6%). CONCLUSION The risk of severe periodontal healing complications in teeth with extrusive and lateral luxation injuries is generally low. Marginal bone loss and repair-related resorption occurred significantly more often in teeth with mature rather than immature root development. Marginal bone loss was associated with injuries involving multiple teeth.