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Biomedical subjects

R Ranta

Publications and source records attributed to R Ranta.

At least 73 records · Page 4Linked to original sources
PubMed1986

A review of tooth formation in children with cleft lip/palate.

The literature on tooth formation in children with cleft lip and/or palate is reviewed. The main focus of interest is the association of cleft type and dental abnormalities in number, size, shape, timing of formation, and eruption and cause of the abnormalities. The upper lateral incisor is the most susceptible to injury in the area of cleft in both deciduous and permanent dentitions. This tooth is affected in most instances, even in the cases of microforms of the cleft lip. The prevalence of hypodontia increases strongly with the severity of cleft. More teeth are congenitally missing from the upper jaw than from the lower jaw; however, in the permanent dentition both jaws are affected. Very high prevalence of hypodontia are observed in connection with the Van der Woude syndrome associated with cleft and with the Pierre Robin anomaly. Hypodontia is similarly prevalent in subjects with isolated cleft palate with and without a positive family history of clefts. The prevalence of hypodontia varies largely in different populations. Asymmetric formation of the contralateral teeth is a milder form of hypodontia. The prevalence of asymmetrically developing pairs of teeth is far more common in children with clefts than in children with normal palates or lips. In the permanent dentition the timing of tooth formation is delayed in children from all cleft groups compared to noncleft children. The delay lengthens (with increasing severity of cleft) from 0.3 to 0.7 years and is similar in all permanent teeth in both jaws. In children with hypodontia, the delay is still more severe. As the child becomes older, the delay may increase.(ABSTRACT TRUNCATED AT 250 WORDS)

Anodontia↗
PubMed1986

Formation of anterior maxillary teeth in 0-3-year-old children with cleft lip and palate and prenatal risk factors for delayed development.

Formation of deciduous and permanent maxillary incisors and canines was studied in 361 children with cleft lip and palate. Altogether, 704 occlusal X rays of the children aged from 2 weeks to 41 months were assessed using a 13-stage scale. The early timing of tooth development was in both dentitions close to that reported for healthy children. However, developmental asymmetry was noted between contralateral teeth on the cleft and noncleft sides. In the unilateral cleft lip and palate group, every tenth cleft-side deciduous central incisor, deciduous canine, and permanent central incisor was delayed compared to the corresponding contralateral tooth. The formation timing was also compared within 11 prenatal and hereditary variables. Risk factors for delayed development were low placental weight, short gestation, mother's use of drugs during pregnancy, first in birth order, cleft with multiple additional malformations, and relatives having malformations other than oral clefts. However, the associations between a risk factor and tooth development were weak.

Aging↗
PubMed1985

Correlations of sinus, conical elevation, median depression of the lower lip and types of oral clefts.

The incidence of autosomal dominantly inherited Van der Woude's syndrome among Finnish patients with cleft lip and palate CL(P) and with isolated cleft palate (CP) is approximately 2.5%. The incidence of conical elevation of the lower lip (CE) is 39% in CP and 0.8% in CL(P) patients. A pathogenetic similarity of sinuses and CE's was noted. The following classification was used to study associations between sinuses and CE's: (1) sinus; bilateral, unilateral, atypical; (2) CE: bilateral, unilateral; (3) median depression of the lower lip (MD); (4) combined sinus and CE; (5) combined CE and MD. According to the classification developed, a group of 77 sinus patients and 156 CE and/or MD patients was classified in subgroups of CL(P), CP, Pierre Robin anomalad (PR) and non-cleft subjects. The findings were: the sinus was bilateral on 52%, unilateral in 34% and atypical in 14%; the CE without associated sinus was bilateral in all cases; the sinus was associated with CE in 77% of all sinus subjects. The highly increased incidence of the CE in the CP (92%) and in the CL(P) (61%) sinus groups compared to the incidences of CE in these groups in general (39% and 0.8%) shows a close relationship between these 2 disorders of the lower lip, but the similarity of the genetic etiology still remains unclear.

Child↗
PubMed1985

Nasomaxillary hypoplasia--Binder's syndrome. Morphology and treatment of two separate varieties.

Two varieties of nasomaxillary dysplasia are presented in 13 patients; one with a nose of normal length and another with a short nose. Several cephalometric and soft tissue differences and similarities are found between these groups. Orthodontic treatment of the malocclusion and nasal reconstruction with an L-shaped iliac bone graft composed of two pegs is the treatment of choice. In the short nose variety, the tight nasal mucosa has to be lengthened with an auricular composite graft.

Adolescent↗
PubMed1984

Incomplete median cleft of the lower lip associated with cleft palate, the Pierre Robin anomaly or hypodontia.

12 female subjects with an incomplete median cleft of the lower lip associated with cleft palate in 7 subjects, with the Pierre Robin anomaly in 3 and with only agenesis of the lower permanent central incisors in 2, are presented. In all subjects, the bony structure of the lower jaw was within normal limits and without cleft. The literature on median clefts of the lower lip and mandible is reviewed and the findings in the present 12 cases compared with 46 reviewed cases.

Anodontia↗
PubMed1984

Associations of some variables to tooth formation in children with isolated cleft palate.

The timing of tooth formation in 251 children, affected with isolated cleft palate without syndromes or other concomitant visceral anomalies (CP), was evaluated from orthopantomograms. The age range was 6-12 yr. The formation of the permanent teeth was delayed approximately 0.7 yr in CP children compared with the data on the non-cleft reference group. There were no differences in sex distribution between the CP group and the non-cleft reference group and between the CP subgroups. No significant differences in tooth formation could be detected between the subgroups; with and without positive family history of clefts, with and without conical elevation of the lower lip, and between the subgroups of submucous, partial and complete cleft of the palate. The presence of hypodontia promoted the delay significantly and the delay increased with increasing number of missing teeth per child. In the older age group of 9-12 yr, the delay was significantly longer (1.1 yr) than in the younger age group of 6-9 yr (0.6 yr). The present findings of tooth formation support the hypothesis that the genetic component in the multifactorial situation does not act directly in producing the malformation itself, but indirectly, through a reduction in buffering. Furthermore, at least some of the sporadic cases have a partly genetic etiology.

Age Determination by Teeth↗
PubMed1984

Separate clefts of the lip and the palate. A variant of cleft lip and palate.

Separate clefts of the lip and of the palate (CL-CP) may belong to the same etiological class as the cleft lip with or without cleft palate CL(P), or a child may have two separate anomalies, CL and CP. This theory was tested in Finnish cleft patients. Among 2471 cleft cases, there were 66 CL-CP (2.7%). Adequate medical records were available for 62 children: 45 boys (73%) and 17 girls (27%). Familial occurrence was recorded in 6 cases (10%). Of the cleft cases among the near relatives, 5 were CL(P) and one CP. The prevalence of hypodontia was 37% among 38 subjects studied, as compared with 8.2% in the CL-, 29.8% in the CP- and 48.1% in the CLP controls. Conical elevations of the lower lip were observed in none, as compared with 0.8% of the CL(P)- and 39% of the CP controls. It was therefore assumed that the CL-CP belongs to the same etiological class as the CL(P).

Adolescent↗
PubMed1984

On the pathogenesis of cleft palate in the Pierre Robin syndrome.

In a series of Pierre Robin syndrome (PRS) and isolated cleft palate patients (ICP) both U- and V-formed clefts were observed with equal frequency, but the PRS clefts were in average slightly wider. There were totally submucous clefts among the PRS patients. There was no statistical difference between the groups in the prevalence of clefts in the relatives of the patients. The incidence of (genetically influenced) conical elevations in the lower lip was lowest in the noncleft subjects, high in ICP and highest in PRS children. The incidence of hypodontia, which acceptedly is genetically influenced, was also highest in the PRS group. Thus the foetal malposition with the tongue between the palatal shelves does not seem to play any decisive role in the pathogenesis of most PRS clefts. The cause for the PRS is more likely a genetically influenced growth disturbance in the maxilla and the mandible, which due to the organogenetic differences leads to diverging end results, micrognathia and cleft.

Anodontia↗
PubMed1983

Correlations between microforms of the Van der Woude syndrome and cleft palate.

The lower lip was examined in 397 children with isolated cleft palate (CP), in 518 cleft lip children with or without cleft palate (CL(P)) and in 1000 noncleft children. Familial occurrence of clefts, other concomitant anomalies and the type and extension of the cleft were determined from the child's medical history. A total of 323 orthopantomograms, taken at the ages of 6-12 years, were available in the detection of hypodontia of the permanent teeth excluding the third molars in the CP group. The incidence of lower lip sinus and microforms (conical elevations, CE) was noted. The incidence of sinuses was 2.3% in the CP group, 2.5% in the CL(P) group and 0% in the noncleft group. The corresponding figures for CE were 39.3%, 0.8% and 0.7%, respectively. In the CP group with CE, the familial occurrence of clefts was statistically higher (30.0%) than in the group without CE (20.7%). The corresponding figures for hypodontia were 40.7% and 24.7%, respectively. Conical elevations are cleft palate related disturbances in the development of the lower lip. At least in certain cases the CE do represent microforms of the sinus syndrome. Thus the question arises: do the CE always represent microforms of the Van der Woude syndrome, or are they only pathogenic similarities of a variable etiology?

Adolescent↗
PubMed1983

Correlations of hypodontia in children with isolated cleft palate.

A total of 251 children with isolated cleft palate were examined. Orthopantomograms, taken at the age of 6-12 years, were used in the detection of hypodontia of the permanent teeth, excluding the third molars. The findings were: 1. Familial history of clefting has no pronounced effect on the prevalence of hypodontia; 2. The prevalence of hypodontia was significantly higher in children with conical elevation of the lower lip than in those without it (40% to 25%), and increased with increasing extension of the cleft; 3. Cleft palate was associated with conical elevation and/or hypodontia in 56% of the subjects. The same etiological factor or factors seems to be responsible for the formation of the cleft, for conical elevation, and for hypodontia.

Anodontia↗