Lateral Incisor Agenesis Research Articles

Prevalence of isolated maxillary lateral incisor agenesis in Syrian adolescents.

This research is designed to obtain a better understanding and provide more insight of this phenomenon through evaluating the prevalence of congenital absence of maxillary lateral incisors in a Syrian population. The method involved clinical examination of 8000 school children with an equal number of males and females (age range 12-15years) to identify students only affected by bilateral or unilateral congenital absence of maxillary lateral incisors. Agenesis was determined based on radiological evidence. The results of this study showed that the prevalence of isolated maxillary lateral incisors agenesis was 1.15%. In the sample studied, 66.3% of the patients were female and 33.7% were male (p<0.05). Absence was bilateral in 47.8% of patients and unilateral in 52.2%. Of the unilateral cases, 48% occurred on the right side and 52% on the left side, and the contralateral maxillary incisor was found to be microdont in 43.75%, right lateral in 47.6%, and left lateral in 52.4%. The results of this study allow the conclusion that the prevalence of isolated maxillary lateral incisors agenesis in a Syrian population is within the average range with regard to other populations. A significant familial component to the etiology of maxillary lateral incisors agenesis was found.

Study of alveolar ridge dimensions before and after orthodontic treatment in maxillary lateral incisor agenesis: A pilot study.

A total of 228 measurements were performed on plaster models and panoramic radiographs: before (T1), at the end of (T2), and 1 year after orthodontic treatment (T3). At stage T2, the cone beam-computed tomography was also analyzed. Non-parametric tests were used. In all 3 stages, there was no statistically significant difference regarding the thickness of the models, the height of the bone in the panoramic radiographs, the space opening and the height of the bone in the panoramic radiographs, or the space opening in the models and the thickness in the same plaster models. However, a statistically significant difference was observed for the width in the panoramic radiograph during all 3 stages. Cone beam-computed tomography did not reveal a statistically significant correlation regarding the height and width of the bone compared with the panoramic radiographs, and the thickness as compared with plaster models. There was no significant variation in thickness, height and width of the bone over time. It was demonstrated that plaster models and panoramic radiographs do not appear to be good substitutes for cone beam-computed tomography for these specific measurements.

Three-dimensional evaluation of root dimensions and alveolar ridge width of maxillary lateral incisors in patients with unilateral agenesis

BackgroundThe objective of this retrospective case-control study was to measure the maxillary lateral incisor root dimensions and quantify the labial and palatal bone in patients with unilateral maxillary lateral incisor agenesis (MLIA) after orthodontic treatment and compare them to non-agenesis controls using cone beam computed tomography.MethodsThe labiopalatal and mesiodistal root dimensions, mesiodistal coronal dimensions, and labiopalatal bone and alveolar ridge widths of the maxillary lateral incisor were assessed on posttreatment cone beam computed tomography scans of 15 patients (mean age 16.5 ± 3.4 years, 9 females and 6 males) with maxillary lateral incisor agenesis and 15 gender-matched patients (mean age 16.08 ± 3.23 years) with no dental agenesis or anterior Bolton discrepancy. The Mann-Whitney test was used to distinguish any differences in root width, crown width, or changes in labial or palatal bone width between the two groups.ResultsThe median labiopalatal root width was narrower in the MLIA group at the level of the cementoenamel junction (CEJ) to 8 mm apical of the CEJ compared to controls (p ≤ 0.009). The mesiodistal root width was significantly reduced in the MLIA group at the CEJ and at 4 mm apical to the CEJ. The labiopalatal alveolar ridge width was significantly decreased at 2 mm apical to the CEJ in MLIA group. The mesiodistal crown width was significantly smaller in the MLIA group at both the incisal edge and at the crown midpoint. The bone thickness was similar in both groups.ConclusionsCoronal and root dimensions in patients with MLIA were reduced compared to controls. Alveolar ridge width was also reduced in patients with MLIA, although bone thickness was not different than controls.

Long-Term Esthetic Evaluation of the Roll Flap Technique in the Implant Rehabilitation of Patients with Agenesis of Maxillary Lateral Incisors: 10-Year Follow-Up

The use of the roll pedicle flap has been recommended by various authors, but there are no studies evaluating the stability of the augmented soft tissue in the long term. The aim of this retrospective study was to evaluate the stability of peri-implant soft tissue augmented with the roll flap technique in patients with congenitally missing maxillary lateral incisors after 10 years of function. Patients with congenitally missing maxillary lateral incisors restored with dental implants in the period between 2000 and 2002 were invited for reexamination after 10 years. The esthetic of the peri-implant soft tissue was evaluated with Furhauser's pink esthetic score (PES). The peri-implant soft tissue of 21 implants in 17 patients was evaluated at the 10-year follow-up. No implants were lost within the duration. The PES score was slightly improved from 11.43 ± 1.504 at baseline to 11.70 ± 1.793 at the 10-year follow-up examination without a statistically significant difference (P > .05). Within the limitations of this study, the roll flap technique was found to be a sustainable method for the achievement of durable peri-implant esthetics in the anterior maxillary region, especially in terms of variables related to tissue contour and appearance.

Prosthetic replacement vs space closure for maxillary lateral incisor agenesis: A systematic review

Defining the best treatment for maxillary lateral incisor agenesis is a challenge. Our aim in this study was to determine, with the evidence available in the literature, the best treatment for maxillary lateral incisor agenesis in the permanent dentition, evaluating the esthetic, occlusal (functional), and periodontal results between prosthetic replacement and orthodontic space closure. Electronic databases (CENTRAL, PubMed, Web of Science, Scopus, and LILACS) were searched in September 2014 and updated in January 2015, with no restriction on language or initial date. A manual search of the reference lists of the potential studies was performed. Risk of bias was assessed by the Newcastle Ottawa Scale. The search identified 2174 articles, of which 1196 were excluded because they were duplicates. Titles and abstracts of 978 articles were accessed, and 957 were excluded. In total, 21 articles were read in full, and 9 case-control studies were included after applying the inclusion and exclusion criteria. Data were extracted from the articles selected, and a table was compiled for comparison and analysis of the results. There were no randomization and blinding, and the risk of bias evaluation found gaps in compatibility and outcome domains in almost all selected studies. Tooth-supported dental prostheses of maxillary lateral incisor agenesis had worse scores in the periodontal indexes than did orthodontic space closure. Space closure is evaluated better esthetically than prosthetic replacements, and the presence or absence of a Class I relationship of the canines showed no relationship with occlusal function or with signs and symptoms of temporomandibular disorders.

Great expectations of patients with missing lateral incisors: when are space opening and space closure appropriate?

On average, 2% of the UK population have agenesis of the permanent maxillary lateral incisors. Reopening the space for restorative replacement or closing the space and subsequent reshaping of the canine depends on a number of factors. Among these are the aesthetics of the canines, level of the smile line, gingival architecture and occlusion. Joint orthodontic and restorative planning to determine the appropriateness of space opening or space closing, with a discussion of these in context with the expectations of the patient/parent, is important before commencing treatment. Despite advances in materials and techniques within both restorative and orthodontic specialties resulting in improvements in the aesthetic outcomes of hypodontia cases, the management of patient/parent expectations is key to overall success. This paper details the contemporary restorative–orthodontic treatment options for the management of missing lateral incisors, the orthodontic biomechanics and restorative approaches involved in treatment.

Prevalence of maxillary lateral incisor agenesis and associated skeletal characteristics in an orthodontic patient population

Objectives: This study was aimed to investigate the prevalence of maxillary lateral incisor agenesis and associated skeletal characteristics in an orthodontic patient population.Materials and methods: The records of the 1066 patients seeking orthodontic treatment were screened for maxillary lateral incisor agenesis (MLIA). The following data were recorded for each subject: age; gender; unilateral or bilateral agenesis of MLI and side. The lateral cephalogram of each subject with MLIA was digitally traced. The data were compared to age-matched control orthodontic patients with skeletal Class I.Results: The prevalence of maxillary lateral incisor agenesis was 4.9% (52 patients) in which 63.5% were females. There was a significant difference between MLIA patients and controls in sagittal relationships (ANB, Wits, AB plane, angle of convexity and Co-A/Co-Gn differential analyses) p < 0.05.Conclusions: Patients with maxillary lateral incisor agenesis showed a significant tendency for skeletal Class III compared with the Class I control. This could be attributed to maxillary hypoplasia/retrognathia.

Upper arch forms in cases with bilaterally missing upper lateral incisors after space closure

IntroductionPatients with missing upper lateral incisors are challenging to treat and an ideal result does not exist, although there is evidence that good results may be achieved with both canine mesialization and space opening. The aim of this retrospective study was to evaluate if the closure of the spaces in bilateral agenesis of the upper lateral incisors may affect the final upper arch form. MethodsThe initial and final dental casts of 26 adult patients (20 women and 6 men) with bilaterally missing lateral incisors treated with space closure (study group) were collected by the archives of four different orthodontists and were chosen based on the high-quality final results. Results were compared with those achieved by the same orthodontists on the initial and final casts of 26 adult patients with full dentition (20 men and 6 women) treated without extractions (control group). All upper dental casts were scanned to retrieve arch-forms, determine spatial coordinates, and perform quantitative measurements to interpolate the curves representing the form of the arches. ResultsClosure space treatment induces great changes in the arch length, no changes in intercanine width, and a little reduction of intermolar distance. When compared with those found in the control group, the final upper arches of the experimental group were flattened in the anterior zone and reduced in the anteroposterior dimension. This result was independent from the technique (type of brackets, prescriptions in the brackets, archwire sequence, archform) used by the four orthodontists who had treated the cases. ConclusionsWhen spaces were closed in cases with bilaterally missing lateral incisors, the anteroposterior dimension suffered the most important modifications.

Failure in anterior rehabilitation of agenesic maxillary lateral incisors

Agenesis of the maxillary lateral incisors poses particular problems for dentists, orthodontists and patients. Treatment of these ageneses is still highly controversial, both functionally and esthetically. The patient's smile and anterior guidance are affected and must be restored. The diagnosis is easy. Few mistakes are possible. However, managing patients with missing maxillary lateral incisors can be a challenge, commonly involving two possible treatment approaches: space opening to replace the missing lateral incisor with a prosthetic unit (denture, bridge or implant) or orthodontic space closure replacing the missing lateral incisor with the maxillary canine camouflaged to mimic the appearance of a lateral incisor. One of these two options will be adopted using multiple means...liable to trigger a multitude of possible errors. Ultimately, optimal results can only be achieved if there is excellent coordination between different practitioners in various specialties. Each clinician will have a specific role to play. Also, the patient and family are at the heart of the decision-making process, by virtue of their consent (treatment duration, financial resources) and their motivation. This multi-factorial, multi-disciplinary decision process means that treatment of the lateral incisor is an ongoing challenge for the clinician striving for the best possible result. Each case is different. No set rules exist. No single factor can be neglected if we are to avoid "failure".

Agenesis of Maxillary Lateral Incisors: Treatment Involves Much More Than Just Canine Guidance.

Objective:In this study, we aimed highlight some clinical features present in patients whose maxillary lateral incisors are missing, and proposed more logical, rational and predictable solutions to inform decision making in rehabilitation procedures.Methods:Literature review and discussion.Conclusion:Choosing the best possible treatment for congenital absence of maxillary lateral incisors depends on the multidisciplinary diagnosis of facial, occlusal, functional and periodontal features. It also depends on the individual long-term stability, and it does not only rely on canine-guided disocclusion.

Esthetic perception of maxillary lateral incisor agenesis treatment by canine mesialization.

The objective of this study was to evaluate perception of the smile in maxillary lateral incisor agenesis (MLIA) cases treated by mesialization of a canine. Nine images were digitally modified from the same frontal intraoral photograph to simulate various treatment options for space closure in MLIA. A questionnaire was submitted to laypersons (303), general dentists (215), prosthodontists (55) and orthodontists (81). Statistical tests with a significance level of P<0.05 were used. The views of MLIA treatment judged to be most attractive showed unilateral dental and gingival reshaping. All study groups considered the simple dental reshaping of the mesial edge of the canine to be attractive. In the analysis of the images grouped together for both unilateral and bilateral MLIA, the view showing dental and gingival reshaping was considered the most attractive whereas unmodified mesialization was considered the least attractive. Regarding the space closure treatments, although all groups regarded simple dental reshaping of the canine to be attractive, the dental professionals considered gingival and crown reshaping to be more esthetic. In contrast, laypersons were not significantly responsive to this dental and gingival modification as compared to only slight reshaping of the mesial edge of the cusp of the mesialized canine in MLIA.

Implant-Prosthetic Rehabilitation in Bilateral Agenesis of Maxillary Lateral Incisors with a Mini Split Crest.

The reported clinical case describes the surgical procedure of ridge augmentation by using a “split crest” technique with a partial thickness flap and a subsequent implant-prosthetic rehabilitation aimed at treating a bilateral agenesis of the upper lateral incisors. In such cases with vestibule-palatal and mesial-distal scarce bone thicknesses associated with the need of a proper functional and aesthetic rehabilitation, the split crest technique is particularly suitable. In the case we reported, because of the poor bone thicknesses, we performed a minimally invasive split crest which allowed a correct insertion of the fixtures. This technique allowed us to achieve an optimal functional and aesthetic rehabilitation; moreover, we obtained a good emergency profile, ensuring the vitality of the close teeth and ensuring a good primary stability and the following osseointegration of dental implants.

Tomographic Assessment of Bone Formation After the Collares Technique of Gingivoperiosteoplasty in Patients With Cleft Lip and Palate.

This cross-sectional study sought to assess bone formation and spontaneous tooth eruption in a cohort of 25 consecutive patients aged 6 to 11 years who underwent primary gingivoperiosteoplasty by the Collares technique. Cross-sectional study assessing bone formation in the cleft area using a within-group time series design. Hospital de Clínicas de Porto Alegre (HCPA), a tertiary hospital in Brazil. Twenty-five patients with nonsyndromic, complete unilateral cleft lip and palate, no comorbidities, and unerupted permanent canines. Cheiloplasty was performed by means of the Millard II technique, with the addition of a triangle at the mucocutaneous junction, vomer flap nasal floor closure, and wide subperiosteal elevation, followed by gingivoperiosteoplasty by the Collares technique. Cone-beam computed tomography was used to assess treatment effect. In a novel method, software was used to obtain two three-dimensional reconstructions, one each of the cleft and noncleft sides, enabling quantitative comparison of bone presence in the alveolar defect area. Of the 25 patients, 24 achieved bone bridge formation. The cleft side had 75.1% (67.9%-82.3%) of the bone volume, 70.5% (53.1%-87.9%) of the height, and 63.3% (44.1%-82.5%) of the width of the noncleft side. Bone formation was 17.28% lower in patients with lateral incisor agenesis. Collares gingivoperiosteoplasty performed well as a technique for alveolar repair in patients with cleft lip and palate, allowing spontaneous eruption of deciduous and permanent lateral incisors through the bone bridge created.

Oral and Physical Manifestations of a Patient with Trisomy 16: Report of an Unusual Case

Clinical report of a 27-year-old patient diagnosed with trisomy 16 and congenital cervical scoliosis; within the oral clinical manifestations of the disease were found agenesis of upper lateral incisors, ankyloglossia, over-inserted labial frenulum and high and arched palate; also the patient showed generalized marginal gingivitis associated to plaque with a loss of attachment level in dental organs 31 and 41. Partial or complete trisomy 16 are considered non-compatible with life; this anomaly corresponds to 2% of the causes of abortion in the first trimester; SH and DP Roberts Duckett reported a case of survival of 10 months, and in this case, the survival is 27 years.

Symmetrical agenesis of the mandibular third molars and agenesis of other teeth in a Japanese orthodontic population.

This study was conducted to investigate the association between symmetrical agenesis of the mandibular third molars and agenesis of other teeth in Japanese orthodontic patients. A sample of 64 patients with symmetrical agenesis of the mandibular third molars and without agenesis of the maxillary third molars was selected as the third molar agenesis group. In addition, 585 patients with all 4 third molars were selected as controls. The main materials examined for diagnosis of tooth agenesis were panoramic radiographs. The prevalence rate of tooth agenesis was compared between the groups using the chi-squared or Fisher's test, and the odds ratio. Significantly increased occurrence of overall agenesis of the maxillary lateral incisors, and overall and symmetrical agenesis of other teeth including the maxillary and mandibular second premolars and mandibular first molars were observed in the patients with symmetrical agenesis of the mandibular third molars and without agenesis of the maxillary third molars. Irrespective of the presence or absence of symmetrical agenesis of the mandibular third molars, no significant differences in the prevalence rates of overall or symmetrical agenesis of other teeth and specific teeth were noted between the sexes or between the right and left sides of the jaws in the patients without maxillary third molar agenesis. (J Oral Sci 58, 171-176, 2016).

Fusion of Primary Mandibular Anterior Teeth Associated with Partial Anodontia of Primary and Permanent Dentition: A Case Report

Fusion is a developmental anomaly of the teeth. It is defined as the union of two independently developing primary or permanent teeth. Aberrations in morpho differentiation stage of tooth development lead to abnormal forms and sizes of teeth. This paper reports a rare case which had the presence of fused primary incisors in the right mandibular region along with agenesis of primary and permanent mandibular left lateral incisor.

Agenesis of lateral incisors: A fresh look at our practice.

In cases involving compensation treatment for edentulousness related to agenesis of the lateral incisors, the transition phase between the orthodontic and the prosthetic stages is tricky. Using clinical illustrations, we will demonstrate that it is time we took a fresh look at our practices. The aim will be to shorten this phase either by postponing the orthodontic stage into adulthood or by placing the prosthesis as quickly as possible on completion of the orthodontic stage, a process which is now feasible, thanks to advances in the designing of bonded bridges and notably of cantilever bonded bridges.

Maxillary lateral incisor agenesis and its relationship to overall tooth size

Statement of problemAgenesis of the maxillary lateral incisor has been linked to differences in the size of the remaining teeth. Thus, the mesiodistal space required for definitive esthetic restoration in patients with missing maxillary lateral incisors may be reduced. PurposeThe purpose of this study was to determine whether a tooth size discrepancy exists in orthodontic patients with agenesis of one or both maxillary lateral incisors. Material and methodsForty sets of dental casts from orthodontic patients (19 men and 21 women; mean 15.9 years of age; all of European origin) were collected. All casts had agenesis of one or both maxillary lateral incisors. Teeth were measured with a digital caliper at their greatest mesiodistal width and then compared with those of a control group matched for ethnicity, age, and sex. Four-factor ANOVA with repeated measures of 2 factors was used for statistical analysis (α=.05). ResultsOrthodontic patients with agenesis of one or both maxillary lateral incisors exhibited smaller than normal tooth size compared with the control group. The maxillary arch had a larger tooth size difference between the control and test groups than the mandibular arch (there was a significant Jaw×Group interaction [F=4.78, P=.032]). ConclusionsAgenesis of one or both maxillary lateral incisors is significantly associated with tooth size discrepancy, which may affect the space remaining for restoration of the remaining teeth.

Presurgical Unilateral Cleft Lip Anthropometrics and the Presence of Dental Anomalies

To investigate associations between cleft lip anthropometrics and dental anomalies in the permanent dentition in unilateral cleft lip patients. Retrospective cross-sectional study. Children with unilateral clefts of the lip, with or without cleft palate. Anthropometric lip measurements, made immediately prior to lip repair, were available for each patient. The presence of dental anomalies in the permanent dentition was assessed radiographically. The presence of associations between anthropometric lip measurements and prevalence rates of different dental anomalies were determined using logistic regression analyses. In the 122 included patients, the cleft lateral lip element was deficient in height in 80% and in transverse length in 84% of patients. Patients with more deficient cleft side lateral lip height and less deficient cleft side lateral lip transverse length were more likely to present with cleft side maxillary lateral incisor agenesis. On the other hand, patients with a less deficient cleft side lateral lip height and more deficient cleft side lateral lip transverse length were more likely to present with a cleft side supernumerary maxillary lateral incisor. When looking only at incomplete clefts, the cleft side lateral lip transverse length deficiency was more predictive of the presence of supernumerary maxillary lateral incisors (P = .030), while for complete clefts, the cleft side lateral lip height deficiency was more predictive of the presence of maxillary lateral incisor agenesis (P = .035). In patients with unilateral clefts, cleft lip anthropometrics have a predictive role in determining the occurrence of dental anomalies.

Patterns of bilateral agenesis of maxillary third molars and agenesis of other teeth.

The purpose of this study was to investigate the patterns of bilateral agenesis of maxillary third molars and other tooth agenesis in Japanese orthodontic patients. A group of 262 subjects with bilateral agenesis of maxillary third molars (group A) was divided into three subgroups: group 1A consisting of 114 subjects without agenesis of mandibular third molars; group 2A, 31 subjects with unilateral agenesis of mandibular third molars; and group 3A, 117 subjects with agenesis of all third molars. As controls, 926 other subjects without third molar agenesis were selected (group C). Panoramic radiographs were mainly used to examine for tooth agenesis. The Chi square test and odds ratio were used to make statistical comparisons. The prevalence rates of agenesis of maxillary lateral incisors, mandibular incisors and maxillary and mandibular second premolars, and bilateral agenesis of maxillary lateral incisors and second premolars were significantly higher in any one of the third molar agenesis groups than in the control group. Characteristically, no significant increase in occurrence of bilateral agenesis of mandibular second premolars was demonstrated by the subjects with bilateral agenesis of maxillary third molars. Irrespective of whether unilateral or bilateral agenesis of mandibular third molars is present or not, the Japanese orthodontic patients with bilateral agenesis of maxillary third molars exhibited a significantly increased occurrence of unilateral or bilateral agenesis of maxillary lateral incisors, mandibular incisors and maxillary and mandibular second premolars, except for bilateral agenesis of mandibular incisors and second premolars.