Mandibular incisor extraction therapy

Anterior maxillary distraction for cleft palate associated severe hypoplastic maxillary Class III deformity during adolescence - A case report

This report chronicles the case of an adolescent female with cleft palate associated severe hypoplastic maxillary Class III deformity. Treatment involved anterior maxillary segmental distraction osteogenesis (AMSDO) in conjunction with pre-distraction and post-distraction orthodontics. Following pre-distraction orthodontics, AMSDO was performed using a customized Hyrax distractor assembly. Post-distraction orthodontics helped stabilize distraction outcomes and finalize occlusion. Post-treatment, midface deficiency and prognathic profile improved dramatically with establishment of acceptable interincisal relationship and well-balanced functionally interdigitated occlusion. Three-year follow-up showed excellent morphologic and functional stability. AMSDO is a viable modality that contributes to effective stomatological rehabilitation of patients with cleft maxillary hypoplasia.

Clinical Insights Into Lower Incisor Extraction for Orthodontic Treatment: A Case Report

Extracting a single lower front tooth can be an appropriate treatment for class I malocclusions when the alignment of the upper teeth is normal and there is an adequate overlap of the teeth. This approach is particularly effective in cases of significant crowding in the lower front teeth, especially when the space deficiency exceeds 4-5 mm and the combined width of the lower front teeth surpasses 83 mm. It is also a viable option for malocclusions resulting from discrepancies in tooth size, such as narrower upper front teeth or larger lower front teeth. Research suggests that this method leads to better post-treatment stability compared to the conventional approach of premolar extraction. The success of this treatment is contingent upon meticulous diagnosis, comprehensive planning, and the expertise of the orthodontic professional. This method not only addresses specific issues of space and alignment but also provides a more stable and predictable long-term outcome for patients with these particular orthodontic challenges.

Assessment of the outcomes and stability after mandibular incisor extraction in orthodontic patients: A systematic review and meta-analysis

Background

This study assessed the stability of the outcomes after mandibular incisor extraction (MIE) using intercanine width and peer assessment rating (PAR) scores in orthodontic patients.

Methods

PubMed, Cochrane Library, Science Direct, Google Scholar, Ovid, and SciELO were systematically searched without restrictions until August 2022. A risk of bias assessment was performed using Newcastle-Ottawa Scale (NOS). The Grading of Recommendations, Assessment, Development, and Evaluation tool was used to assess the quality of evidence. Random effects meta-analysis was performed using RevMan software.

Results

Seven retrospective studies met the inclusion criteria and were included. Meta-analysis identified a statistically significant reduction in intercanine width with MIE after the retention period. The mean difference in post-retention changes concerning intercanine width (MD=0.14, 95% CI: -2.17-1.89; P<0.00001) was significantly higher in premolar extraction (PE) compared to incisor extraction and significantly less in non-extraction compared to incisor extraction (MD=0.72, 95% CI: -0.59-2.03; P<0.00001). Improvements in PAR scores from the start of treatment to the retention period indicated a high outcome standard (>70%) with MIE treatment, with no significant difference in the reduction percentage compared to premolar and non-extraction groups.

Conclusion

With the existing retrospective studies of limited evidence, treatment outcomes with MIE were found to show good improvements in PAR scores. Some reduction in the intercanine width was evident after the retention period, which was observed even with the other two treatment modalities that were compared. Hence, with careful evaluation, MIE could be considered a valid treatment option.

Long-term follow-up of a patient with deepbite and severely resorbed maxillary central incisors treated by maxillary premolar and mandibular incisor extraction

Deepbite is a common type of malocclusion, but it leads to difficulties in treatment and retention. We report the treatment of an adult patient with deepbite and severe crowding of teeth. Several teeth had to be restored, and the maxillary central incisors had short roots. Various treatment plans were considered, and extraction of the maxillary right and left first premolars, and mandibular right central incisor was planned. Successful treatment results were obtained with long-term retention.

The influence of 3x3 bonded retainer on anterior crowding relapse in mandibular incisor extraction cases

Objective:

To evaluate the 3x3 bonded retainer influence on the mandibular anterior crowding in cases treated with mandibular incisor extraction

Methods:

The sample comprised pretreatment, posttreatment and follow-up orthodontic records of 16 subjects (10 females and 6 males) with Class I malocclusion treated with extraction of a single mandibular incisor. The mean ages (± SD) at pretreatment, posttreatment and follow-up evaluation were 23.45 ± 9.14 years, 25.50 ± 8.95 years and 30.11 ± 8.59 years, respectively. The mean (± SD) treatment time and posttreatment evaluation time were 2.05 ± 0.45 years and 4.60 ± 1.85 years , respectively. Little irregularity index and interdental widths were evaluated using dental casts. The sample was divided into two subgroups, according to the presence of the 3x3 bonded retainer at follow-up.

Results:

The subgroup without 3x3 bonded retainer presented a greater relapse at the follow-up, when compared to 3x3 bonded retainer subgroup.

Conclusion:

There was a significant relapse in cases treated with mandibular incisor extraction at follow-up. The subgroup without 3x3 bonded retainer showed a significant relapse at the follow-up when compared to the retainer group.

Dissipating tooth-mass discrepancy caused by a set of mandibular incisor anomalies

Dental anomalies are complicating factors of orthodontic treatment, especially when 1 or more anterior teeth are affected. In this case report, a girl, aged 12.5 years with a retrognathic chin; number, size, and position anomalies of the mandibular incisors; and bilateral Class I molar relationship sought orthodontic treatment. Tooth-size ratio discrepancy was dissipated without extraction or prosthetic rehabilitation, and the initial molar relationship was maintained, as well as the straight soft tissue profile. Tipping of maxillary and mandibular incisors, crown torque of canines, restoration of anomalous incisor, and maxillary interproximal enamel reduction were key points for successful treatment. After 18 months, the orthodontic records showed stable results, excellent static and functional occlusion, and good smile esthetics and facial appearance, in addition to a high degree of patient satisfaction with the achieved results.

Evaluation of objective and subjective treatment outcomes in orthodontic cases treated with extraction of a mandibular incisor

OBJECTIVES

To analyze changes in occlusal characteristics following mandibular incisor extractions (MIE), to determine the usefulness of wax setups in treatment planning MIE cases and to compare the pre- and posttreatment dental attractiveness between MIE cases and nonextraction (NE) controls.

MATERIALS AND METHODS

The Peer Assessment Rating (PAR) Index was used to score pre- and posttreatment dental casts of MIE cases (n = 14) and matched NE controls (n = 14). Occlusal characteristics were evaluated on diagnostic wax setups and posttreatment casts. Attractiveness of pre- and posttreatment cases judged on intraoral photographs of cases (n = 6) and controls (n = 6) were rated by 76 dental students and 10 laypeople using visual analogue scales (VAS).

RESULTS

The difference in PAR score reduction (%) between the MIE and NE groups was not significant. Between the wax setup and posttreatment casts, there were moderate correlations in overjet, overbite, and right canine classification. There was no significant difference in pre- and posttreatment change in VAS scores (%) for attractiveness between the MIE (49.8 ± 4.3 [S.E.]) and control groups (40.8 ± 4.3 [S.E.]). However, there was a significant difference (P = .000) between the observer groups.

CONCLUSIONS

There were no significant differences in the treatment outcomes of orthodontic cases treated with MIE or NE, indicating that MIE is a valid treatment option. A wax setup is moderately correlated with posttreatment results. Both laypeople and dental students rated posttreatment dental attractiveness higher than pretreatment in MIE and NE groups. Dental students tended to be more critical than laypeople in their ratings.

A 15-year follow up of an orthodontic treatment including a lower incisor extraction and keeping the maxillary canine-premolar transposition

Lower incisor extraction is an effective option for treating lower anterior crowding in patients with a good facial profile, Class I molar occlusion, and narrow upper incisors. This report describes the successful treatment of an adolescent patient with lower anterior crowding and a transposed maxillary canine and premolar treated by extracting a lower incisor and keeping the transposed positions of the teeth. With the use of retainers, treatment results were stable up to the 2-year postretention visit. However, upon a 15-year postretention appointment, the fixed retainer had been removed and the removable retainer was no longer in use, which resulted in relapse of lower anterior alignment. Moreover, the transposed canine had extruded during this period, causing occlusal interference and gingival recession, as well as loss of tooth vitality, which indicates the importance of maintaining orthodontic retainers for long-term stable occlusion.

A patient with mandibular deviation and 3 mandibular incisors treated with asymmetrically bent improved superelastic nickel-titanium alloy wires

Skeletal and dental discrepancies cause asymmetric malocclusions in orthodontic patients. It is difficult to achieve adequate functional occlusion and guidance in patients with congenital absence of a mandibular incisor due to the tooth-size discrepancy. Here, we describe the orthodontic treatment of a 22-year-old woman with an asymmetric Angle Class II malocclusion, mandibular deviation to the left, and 3 mandibular incisors. The anterior teeth and maxillary canines were crowded. We used an improved superelastic nickel-titanium alloy wire (Tomy International, Tokyo, Japan) to compensate for the asymmetric mandibular arch and an asymmetrically bent archwire to move the maxillary molars distally. A skeletal anchorage system provided traction for intermaxillary elastics, and extractions were not needed. We alleviated the crowding and created an ideal occlusion with proper overjet, overbite, and anterior guidance with Class I canine and molar relationships. This method of treatment with an asymmetrically bent nickel-titanium alloy wire provided proper Class I occlusion and anterior guidance despite the mandibular deviation to the left and 3 mandibular incisors, without the need for extractions.

Mandibular incisor extraction: a 5-year follow-up

This case report presents the mandibular incisor extraction treatment of a patient with dental Class I malocclusion and lower crowding, in whom one mandibular incisor extraction was selected as the treatment of choice to improve the dental occlusion. A 19-year-old male patient’s chief complaint was the crowding of lower incisors. He had a straight profile with normal upper and lower lip projection. Upper and lower dental midlines were coincident with the facial midline. The patient had Class I molar and canine relationships on both sides. He had Class I skeletal relationship, low angle vertical pattern, and proclined upper and lower incisors. The treatment plan included the extraction of lower right central incisor to resolve the crowding. At the end of 16-month active fixed treatment, lower dental crowding was resolved. At the 5-year follow-up, the patient had a stable occlusion, with the results of the orthodontic treatment maintained.

Interproximal wear versus incisors extraction to solve anterior lower crowding: a systematic review

OBJECTIVE

To determine by means of a systematic review the best treatment, whether interproximal wear or incisor extraction, to correct anterior lower crowding in Class I patients in permanent dentition.

METHODS

A literature review was conducted using MEDLINE, Scopus and Web of Science to retrieve studies published between January 1950 and October 2013. In selecting the sample, the following inclusion criteria were applied: studies involving interproximal wear and/or extraction of mandibular incisors, as well as Class I cases with anterior lower crowding in permanent dentition.

RESULTS

Out of a total of 943 articles found after excluding duplicates, 925 were excluded after abstract analysis. After full articles were read, 13 were excluded by the eligibility criteria and one due to methodological quality; therefore, only fours articles remained: two retrospective and two randomized prospective studies. Data were collected, analyzed and organized in tables.

CONCLUSION

Both interproximal wear and mandibular incisor extraction are effective in treating Class I malocclusion in permanent dentition with moderate anterior lower crowding and pleasant facial profile. There is scant evidence to determine the best treatment option for each case. Clinical decision should be made on an individual basis by taking into account dental characteristics, crowding, dental and oral health, patient's expectations and the use of set-up models.

Use of Forsus fatigue-resistant device in a patient with Class I malocclusion and mandibular incisor agenesis

Orthodontic treatment in patients with congenitally missing teeth can be challenging. In this case report, we describe the treatment of a 15-year-old girl with mild dental crowding and 2 congenitally missing mandibular incisors. The Forsus fatigue-resistant device was used to move the mandible and the mandibular teeth forward. A new balanced and stable occlusion was achieved after treatment. When the treatment plan includes moving the mandibular teeth forward in a patient with mandibular incisor agenesis, the profile and the skeletal and dental features should be carefully scrutinized to ensure that balanced and esthetic results are achieved.

Non-surgical, non-extractive treatment of a severe class III malocclusion in permanent dentition: follow-up of a case 24 years posttreatment

This case shows a patient who had presented a severe Class III malocclusion, both maxillary and mandibular crowding and an impacted canine: she is now 24 years posttreatment. She was treated, in permanent dentition, by proclination of both maxillary and mandibular incisors, expansion of the maxillary arch and of the mandibular intercanine width and disinclusion of the impacted canine. At debonding, she presented well-aligned arch forms, a centered midline and a pleasant smile. Twenty-four years after treatment, her records show that the occlusion has remained stable. The use of wires of almost full thickness helped effectively control incisor torque, thus keeping the teeth inside the cortical bone and limiting the expected periodontal problems.

Angle Class I malocclusion treated with lower incisor extraction

In planning orthodontic cases that include extractions as an alternative to solve the problem of negative space discrepancy, the critical decision is to determine which teeth will be extracted. Several aspects must be considered, such as periodontal health, orthodontic mechanics, functional and esthetic alterations, and treatment stability. Despite controversies, extraction of teeth to solve dental crowding is a therapy that has been used for decades. Premolar extractions are the most common, but there are situations in which atypical extractions facilitate mechanics, preserve periodontal health and favor maintenance of the facial profile, which tends to unfavorably change due to facial changes with age. The extraction of a lower incisor, in selected cases, is an effective approach, and literature describes greater post-treatment stability when compared with premolar extractions. This article reports the clinical case of a patient with Angle Class I malocclusion and upper and lower anterior crowding, a balanced face and harmonious facial profile. The presence of gingival and bone recession limited large orthodontic movements. The molars and premolars were well occluded, and the discrepancy was mainly concentrated in the anterior region of the lower dental arch. The extraction of a lower incisor in the most ectopic position and with compromised periodontium, associated with interproximal stripping in the upper and lower arches, was the alternative of choice for this treatment, which restored function, providing improved periodontal health, maintained facial esthetics and allowed finishing with a stable and balanced occlusion. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO), as part of the requirements for obtaining the BBO Diplomate title.

Iatrogenic absence of maxillary canines: Bolton discrepancy treated with mandibular incisor extraction

This case report describes the orthodontic treatment of an adult patient with iatrogenic absence of the maxillary canines, moderate maxillary and severe mandibular dental crowding, a Bolton discrepancy with a large mandibular anterior excess, a maxillary right lateral incisor crossbite, and Angle Class II molar relationships. The treatment consisted of fixed appliance therapy, mandibular incisor extraction, tooth bleaching, and dental recontouring. This method of treatment maintained the patient's good facial appearance, improved the dental esthetics, and provided a good functional occlusion, eliminating the arch length and Bolton discrepancies and providing a good outcome with minimal undesirable effects.

[The extraction of a lower incisor in orthodontics: indications, planning of the treatment and clinical handling in different malocclusions]

The extraction of a lower incisor has been a therapeutic approach considered controversial in orthodontics over the last decades and, therefore, supported by some authors and questioned by others. In recent years, different publications have attempted to provide with substantial and structured information that could help to perform this atypical form of therapy in selected cases with a prospective good result. The purpose of this article is to summarise the available information, providing an order and structure to the diagnostic features that could support the indication and use of this treatment alternative, including the quantification of those parameters that can be measured in the decision-making process. Finally, to set up a clear and meaningful clinical frame that could be used by the orthodontist as a reference line in daily practice. Four case reports will be used in order to illustrate the indication of this treatment modality in different malocclusions.

Mandibular incisor extraction: a systematic review of an uncommon extraction choice in orthodontic treatment

OBJECTIVES

To review the published literature in order to address clinical questions regarding the indications, effects and outcomes of mandibular incisor extraction in orthodontics.

DATA SOURCES

Three electronic databases were searched: PubMed (1950-January 2011), Ovid Embase+Ovid Embase Classic (1947-January 2011) and Cochrane library (6 Cochrane databases, 1996-January 2011). The following journals were additionally searched: American Journal of Orthodontics and Dentofacial Orthopedics (1960-January 2011), Angle Orthodontist (1960-January 2011), European Journal of Orthodontics (1970-January 2011) and Journal of Orthodontics (1974-January 2011). Grey literature was searched using Google Scholar and System for Information on Grey Literature in Europe. Secondary search of the references cited in the relevant articles was also conducted.

DATA SELECTION

Articles in vivo, in Humans, in English, concerning treatment of malocclusion with mandibular incisor extractions or missing mandibular incisors. Fifty-four publications met these inclusion criteria and were reviewed.

DATA EXTRACTION

Data were extracted independently by two reviewers with regard to: (1) indications; (2) contraindications; (3) effects; (4) outcomes; and (5) factors associated with successful outcomes.

DATA SYNTHESIS

Considering the descriptive nature of the studies found, a narrative synthesis was undertaken.

CONCLUSIONS

The descriptive nature of published articles precludes making strong evidence-based recommendations regarding this extraction choice, but it is clear that mandibular incisor extraction can be effectively used in the resolution of crowding, as well as intermaxillary malocclusion in carefully selected cases. Several factors that could lead to good outcomes of orthodontic treatment following mandibular incisor extraction were identified. Mild-to-moderate class III malocclusion, an edge-to-edge anterior occlusion or anterior crossbite, with mild anterior mandibular tooth size excess, and minimal open bite tendencies were the clinical situations most frequently treated with this unique extraction choice. On the other hand, clinicians should be careful to avoid poor outcomes such as gingival recession, open interproximal gingival embrasures, increased overjet and overbite.

Perception of the esthetic impact of mandibular incisor extraction treatment on laypersons, dental professionals, and dental students

OBJECTIVE

To evaluate the degree of perception of laypersons, dental professionals, and dental students regarding dental esthetics in cases with mandibular central incisor extraction.

MATERIALS AND METHODS

Using a smile photograph of a person with normal occlusion and all teeth, modifications were made to reflect the extraction of a mandibular incisor of various compositions and sizes. For this purpose a program specifically for image manipulation (Adobe Photoshop CS3, Adobe Systems Inc) was used. After manipulation the images were printed on photographic paper, attached to a questionnaire and distributed to laypersons, dental professionals, and dental students (n  =  90) to evaluate the degree of perception and esthetic using a scale of attractiveness, where 0  =  hardly attractive, 5  =  attractive, and 10  =  very attractive. The differences between examiners were checked by the Mann-Whitney test. All the statistics were performed with a confidence level of 95%.

RESULTS

The results demonstrated the skill of the dental professionals and dental students in perceiving the difference between cases of normal occlusion and cases where an incisor was lacking (P < .05). The photograph in which the lateral incisors were shown to be larger than the central incisor was the one that obtained the highest value among the cases of extraction in all groups of evaluators.

CONCLUSIONS

It can be concluded that dental professionals and dental students are more skillful at identifying deviation from normality. In addition, central incisor extraction should always be discarded when there are other treatment options available.

Comparison of the outcomes of the lower incisor extraction, premolar extraction and non-extraction treatments

The aim of this retrospective study was to evaluate the treatment outcome of lower incisor extraction and to compare it with premolar extraction and non-extraction treatment. The sample consisted of 60 subjects with Class I malocclusion and moderate crowding. The sample was separated into three groups: extraction of a lower incisor group, extraction of a four first premolar group and a non-extraction group. All groups involved 13 girls and 7 boys with a total of 20 patients. The Peer assessment rating (PAR) index was applied to a patient's pre-treatment (T1) and post-treatment (T2) dental casts. T1 dental casts were also used for determining Bolton discrepancy. One-way analysis of variance and post hoc Tukey HSD tests were used for statistical analysis. For the mean percentage PAR score reduction for each group, there was one significant difference seen between the lower incisor extraction group and the non-extraction group (P = 0.047). For the mean anterior ratios, there were significant differences among premolar extraction group versus non-extraction group (P = 0.042) and non-extraction group versus lower incisor extraction group (P = 0.000). For the mean overall ratios, there were significant differences among the premolar extraction group versus lower incisor extraction group (P = 0.048) and the non-extraction group versus lower incisor extraction group (P = 0.001). Orthodontic treatment without extraction has a better treatment outcome than the four-first premolar extraction and single lower incisor extraction protocols in Class I cases with moderate to severe mandibular anterior crowding.

Incidence of open gingival embrasures after mandibular incisor extractions: a clinical photographic evaluation

INTRODUCTION

The purposes of this study were to determine the incidence of open gingival embrasures after a single mandibular incisor extraction and to investigate whether age, sex, interproximal pretreatment and posttreatment contact location, or the type of mandibular incisor were predictors of the incidence and magnitude of open gingival embrasures.

METHODS

Pretreatment and posttreatment intraoral frontal photos of 51 adults who had 1 mandibular incisor extracted were evaluated to determine the incidence and magnitude of open gingival embrasures.

RESULTS

The incidence of open gingival embrasures was 68%; the embrasures were moderately noticeable to very noticeable in 52% of those patients. Age, sex, incisor type, and location of interproximal contact before treatment were not predictors of open gingival embrasures after mandibular incisor extractions. An interproximal contact in the incisal third at the end of treatment was associated with the formation of an open gingival embrasure.

CONCLUSIONS

Open gingival embrasures are a common finding after the extraction of a mandibular incisor, and the magnitude of this embrasure is clinically noticeable.

Extração de incisivo inferior: uma opção de tratamento ortodôntico

A exodontia de um incisivo inferior pode ser considerada uma opção valiosa na busca de excelência nos resultados ortodônticos para obtenção de máxima função, estética e estabilidade. O objetivo deste estudo foi reunir informações referentes às indicações, contraindicações, vantagens, desvantagens e estabilidade dos resultados obtidos nos tratamentos realizados com extração de um incisivo inferior. Essa opção de tratamento pode ser indicada em más oclusões com discrepância de volume dentário anterior devido a incisivos superiores estreitos e/ou incisivos inferiores largos. É contraindicada em más oclusões sem discrepância anterior ou com discrepâncias ocasionadas por incisivos superiores largos e/ou incisivos inferiores estreitos. A literatura sugere maior estabilidade pós-tratamento quando comparada com a opção de extrações de pré-molares. Além do diagnóstico cuidadoso, obtido com a colaboração do set-up, a habilidade e a experiência clínica do profissional são importantes para o sucesso dos resultados ortodônticos alcançados com essa opção de tratamento

Surgical correction of a Class II skeletal malocclusion associated with anterior open bite and temporomandibular joint pain

This case report describes the treatment of a 25-year-old woman with anterior open bite, Class II skeletal malocclusion, and a history of temporomandibular joint pain and sounds. She also had significant anteroposterior and vertical discrepancies and a convex profile with protrusive lips. Intraorally, she had an anterior open bite of 3 mm and an overjet of 5 mm. Mandibular surgical rotation, associated with mandibular incisor extraction, was performed to reduce the protrusion, close the open bite, and minimize the temporomandibular joint disorder.

Mandibular incisor extraction. Case report

Cranio-mandibular dysfunction therapy of a moderate Angle Class III malocclusion with retroclined incisors with anterior crossbite and pronounced crowding was based not on extraction of the first premolars but on protrusion of the incisors and the extraction of one lower incisor.

Effects of mandibular incisor extraction on anterior occlusion in adults with Class III malocclusion and reduced overbite

The aim of this study was to assess the treatment outcome and changes in mandibular incisor position after extraction of one single incisor in 36 adult orthodontic cases with combined Class III and open bite tendencies. The cases consisted of 21 female and 15 male patients with an average age of 27.8 years (standard deviation [SD], 11.1 years) at the start. Fixed 0.018-inch Edgewise appliances were used in both arches in 19 patients and in the mandibular arch in 17 patients. Average treatment time was 18 months (SD, 7.1 months). Pretreatment ANB was 0.5(o) (SD, 2.7 degrees), overjet 1.4 mm (SD, 1.9 mm), and overbite 1.5 mm (SD, 1.1 mm). The lower incisors were 3.6 mm (SD, 2.8 mm) in front of the APg-line, and the Averaged Irregularity Index was 1.1 mm (SD, 0.6 mm). Records representing pretreatment (T1), posttreatment (T2), and average 4.3 years (SD, 2.3 years) retention (T3) included cephalograms, panoramic films, intraoral and extraoral photographs, and plaster models. All cast measurements were made with digital calipers. On the cephalograms, the lower incisor tips moved posteriorly 1.7 mm (SD, 2.0 mm) and occlusally 1.5 mm (SD, 1.8 mm) from pretreatment to posttreatment. Relative to the x-axis, they tipped lingually 5.9(o) (SD, 5.6 degrees). On the cast analysis, overjet increased 1.0 mm (SD, 1.9 mm) and 1.5 mm (SD, 1.5 mm) for the maxillary central and lateral incisors, respectively, whereas overbite increased 0.6 mm for both the central and lateral incisors. The intercanine width was reduced by 3.3 mm (SD, 2.0 mm), while the intermolar width was unchanged. The Average Irregularity Index was reduced from 1.1 to 0. 2 mm. Arch-length was reduced 3.6 mm from pretreatment to posttreatment, and another 0.3 mm from posttreatment to 4.3-years retention. Other changes from posttreatment to 4.3-years retention were slight. No loss of the interdental gingival papillae was normally observed. It is concluded that the extraction of one mandibular incisor can lead to satisfactory treatment results in adults with mild Class III malocclusion and reduced overbite, particularly when coupled with a large mandibular intercanine width and minor crowding, and some mandibular tooth size excess. However, the orthodontic treatment frequently became more complicated and time-consuming than expected at the start.

The mandibular central incisor, an extraction option

A case report is presented of a female adolescent with a Class II, division 1 malocclusion that shows a significant mandibular arch length deficiency. Although the facial balance suggested a nonextraction approach, the degree of mandibular anterior dental crowding and preexisting gingival recession indicated extraction in the mandibular arch might be preferable.

Extraction of a mandibular incisor in a Class I malocclusion

A single mandibular central incisor was removed to treat a Class I malocclusion with crowding and a midline discrepancy. This case report was submitted under category number 10 (optional) and it was believed that the results illustrated the Board objectives of (1) facial harmony, soft tissue balance, and proper proportion, (2) maximum health of the teeth, the supporting tissues and adjacent structures, (3) maximum esthetics, (4) optimal functional relationships, (5) treatment in harmony with the patient's facial growth, and (6) stability. Beginning, completion, and 2-year retention records are included. The text follows the guidelines established by the Board for content and length included in "Specific Instructions for Candidates." [This case report was presented to the American Board of Orthodontics in partial fulfillment of the requirements for the certification process conducted by the Board.]