Treatment of an adult with several missing teeth and atrophic old mandibular first molar extraction sites

Alveolar bone loss and root resorption in mesialized second molars in mandibular first molar extraction cases as compared to contralateral non-extraction side in young adults: A retrospective cross-sectional study

INTRODUCTION

The alveolar bone loss (ABL) and external apical root resorption (EARR) depict the safety of mesialization of mandibular second molars into the extraction space of mandibular first molars. The aim of this study was to evaluate the ABL and EARR after closure of mandibular first molar extraction space by mesialization of second molar on extraction side (ES) as compared to the contralateral non-extraction side (NES).

MATERIAL AND METHODS

A retrospective cross-sectional study was carried out using the pre and posttreatment orthodontic records of young adults with complete set of permanent dentitions treated with extraction of unilateral mandibular first molar and non-extraction treatment on the contralateral side. All patients underwent mini-implant supported mesialization of second molar on ES. The ABL and EARR of second molar on ES and contralateral NES were measured on digital orthopantomograms. The ABL and EARR of second molars on ES and contralateral NES were compared using independent sample t-test.

RESULTS

A total of 36 subjects (14 males and 22 females) were included in the study. The mean treatment duration for molar mesialization was 28.75±8.05months. The mean crown and root movements of mandibular second molar on ES were 10.94±1.25mm and 9.04mm±1.14mm, as compared to 0.91±1.01mm and 0.77±0.83mm on contralateral NES, respectively. The mean ABL and EARR at mandibular second molar were found to be significantly greater on the ES than the contralateral NES (P<0.001 and<0.05, respectively). A total of seven patients (19.4%) experienced ABL≥1mm on ES as compared to none in the contralateral NES. EARR of>2mm of at least one root was found in seven patients (19.4%) in ES as compared to four (11%) in contralateral NES.

CONCLUSION

There was small but statistically significant difference in the ABL and EARR of mesialized mandibular second molar at first molar ES as compared to the contralateral NES. For majority of patients this difference was small but few isolated cases experienced severe ABL and EARR.

Characteristics of Spatial Changes in Molars and Alveolar Bone Resorption among Patients with Loss of Mandibular First Molars: A CBCT-Based Morphometric Study

OBJECTIVES

To investigate the characteristics of spatial changes in molars and alveolar bone resorption among patients with loss of mandibular first molars.

METHODS

A total of 42 CBCT scans of patients with missing mandibular first molars (3 males, 33 females) and 42 CBCT scans of control subjects without loss of mandibular first molars (9 males, 27 females) were evaluated in this cross-sectional study. All images were standardized using the mandibular posterior tooth plane with Invivo software. The following indices regarding alveolar bone morphology were measured, including alveolar bone height, bone width, mesiodistal and buccolingual angulation of molars, overeruption of maxillary first molars, bone defects, and the capability of molar mesialization.

RESULTS

The vertical alveolar bone height in the missing group was reduced by 1.42 ± 0.70 mm, 1.31 ± 0.68, and 1.46 ± 0.85 mm on the buccal, middle, and lingual side, respectively (no differences among the three sides; p > 0.05). Alveolar bone width was reduced the greatest at the buccal CEJ level and the least at the lingual apex level. Mandibular second molar mesial tipping (with mean of the mesiodistal angulation = 57.47 ± 10.34°) and lingual tipping (with mean of the buccolingual angulation = 71.75 ± 8.34°) were observed. The mesial and distal cusps of maxillary first molars were extruded by 1.37 mm and 0.85 mm, respectively. Buccal and lingual defects of alveolar bone occurred at the CEJ, mid-root, and apex levels. Through 3D simulation, the second molar cannot be successfully mesialized into the missing tooth position, and the difference between the available and required distances for mesialization was the greatest at the CEJ level. The duration of tooth loss was significantly correlated with the mesio-distal angulation (R = -0.726, p < 0.001), buccal-lingual angulation (R = -0.528, p < 0.001) and the extrusion of the maxillary first molar (R = -0.334, p < 0.05).

CONCLUSION

Both vertical and horizontal resorption of alveolar bone occurred. Mandibular second molars exhibit mesial and lingual tipping. Lingual root torque and uprighting of the second molars are needed for the success of molar protraction. Bone augmentation is indicated for severely resorbed alveolar bone.

Molar space closure: To do or not to do?

Missing or compromised permanent molars can complicate orthodontic treatment planning and mechanics. Molar extraction should be considered in appropriate situations, but clinicians must decide between closing and regaining the edentulous space. Several factors should be taken into consideration to achieve appropriate molar space management, such as the need for space, asymmetry, periodontal status, sinus pneumatization, and the terminal molar position. Herein, three sample cases are reported to demonstrate the treatment options for molar space closure and maintenance with these factors taken into consideration during treatment planning. The understanding of mechanics played a crucial role in anchorage preparation and side effect prevention. If the third molar substitution was managed in advance and adequate space between the ramus and third molar was obtained via second molar protraction, the tooth spontaneously erupted in a favorable position without requiring further treatment. This case series can aid clinicians in molar space management. Regardless of whether the space is to be closed or regained, the treatment plan should conform to the patient’s expectations and improve occlusion with minimal side effects and treatment duration.

Nonsurgical treatment of a hyperdivergent skeletal Class III patient with mini-screw-assisted mandibular dentition distalization and flattening of the occlusal plane

Treatment of hyperdivergent skeletal Class III malocclusion is challenging for orthodontists, and orthognathic-orthodontic treatment is usually required. This report presents the successful nonsurgical treatment of a 20-year-old man who had a skeletal Class III malocclusion with anterior open bite, anterior and posterior crossbite, hyperdivergent growth pattern, steep occlusal plane, early loss of three first molars, and an uncommon convex profile with a retruded chin. An orthodontic camouflage treatment plan was chosen based on the etiology and the patient's complaints. Tooth #37 was extracted. Miniscrews were used for uprighting and intruding of the lower molars, distalization of the lower dentition, and flattening of the occlusal plane. After 34 months of active treatment, Class I relationships, proper anterior overjet and overbite, flat occlusal plane, and an esthetic facial profile were achieved. The results demonstrated that the biomechanics involved in the nonsurgical treatment assisted with miniscrews to distalize the mandibular dentition and flatten the occlusal plane while keeping the mandibular plane stable was effective for treating this hyperdivergent skeletal Class III patient with a convex profile and anterior open bite.

Multidisciplinary management of permanent first molar extractions

The first molar has been reported to be the most caries prone tooth in the permanent dentition. Orthodontists are treating more adult patients who are more likely to have missing and severely decayed first molars. This article will show the various orthodontic and restorative options for first molars that are already extracted or have to be extracted. The following clinical situations will be addressed: molar uprighting and its advantages for the future restoration vs orthodontic space closure, strategic extraction of salvable first molars, impacted molars, and early extraction of compromised permanent first molars in young children.

Sequelae of premature loss of lower permanent molars on developing occlusion during the mixed dentition period-A radiographic evaluation

When planning extraction of teeth with poor prognosis especially lower first permanent molars, it is important to consider the timing of tooth removal and its effect on future occlusion to avoid interventions.

Protraction of mandibular molars through a severely atrophic edentulous space in a case of juvenile periodontitis

Moving the mandibular posterior teeth into a severely atrophic edentulous space is a challenge. A carefully designed force-and-moment system that results in bodily protraction of the posterior teeth with balanced bone resorption and apposition is needed in such cases. This report describes the treatment of a 19-year-old woman with missing mandibular first molars due to juvenile periodontitis. Miniscrews were used as absolute anchorage during protraction of the mandibular second and third molars. Bodily mesial movement of the mandibular second and third molars was achieved over a distance of 11 to 17 mm after 39 months of orthodontic treatment.

Orthodontic treatment with passive eruption and mesialization of semi-impacted mandibular third molar in an adult with multiple dental losses

Objective:

This article describes the orthodontic treatment performed on an adult patient with multiple dental losses.

Case report:

A female patient, 20 years and 4 months old, presented with the following conditions: absence of teeth #26, #35, #36 and #46; semi-impacted tooth #48; inclined molars adjacent to an edentulous space; canines and premolars in a Class II relationship; a convex profile; biprotrusion; and forced lip sealing.

Results:

Space in the region of tooth #26 was closed, as well the space of tooth #46; tooth #48 erupted and followed mesial movement passively; space of the region of tooth #35 was maintained for the placement of a dental implant; uprighting of tooth #37 was obtained. Aesthetic and functional goals of the treatment were achieved. Results remained stable 10 years after the end of the treatment.

Conclusion:

The modified helical loop could be effectively used in orthodontic mechanics to close edentulous spaces. Passive semi-impacted mandibular third molar eruption and mesialization can occur in adults when proper space is provided.

Change in alveolar bone level of mandibular second and third molars after second molar protraction into missing first molar or second premolar space

Objective

To investigate the factors associated with the change in alveolar bone level of mandibular second and third molars after second molar protraction into the space of the missing first molar (L6) or second premolar (LE).

Methods

Fifty-one patients in whom space of the missing L6 or LE was treated with second molar protraction (13 males, 38 females, mean age 19.6 ± 4.7 years) from 2003 to 2015 were included. The alveolar bone level and position and angulation of the mandibular second and third molars were measured in panoramic radiographs at pre-treatment (T1), and after the alignment of the third molars following second molar protraction (T2). Factors associated with alveolar bone loss on the distal aspect of the mandibular second molars were assessed using linear regression analysis.

Results

Age at T1 (P < 0.001) and third molar angulation at T1 (P = 0.002) were significant factors for the prediction of alveolar bone level distal to the second molars.

Limitation

This study used two-dimensional panoramic radiographs, and we could observe only the interproximal bone level.

Conclusions

After second molar protraction into the missing first molar or second premolar space, mandibular second molars may exhibit alveolar bone resorption in the distal root in older patients and in those with mesially tilted third molars before treatment.

Molar Uprighting: A Considerable and Safe Decision to Avoid Prosthetic Treatment

Background:

Tipped lower molar over edentulous space is very common in orthodontics practice when adults seek treatment. The segmented arch technique features a predictable force system that provides a controlled release of force that can produce light and continuous tooth movement.

Case Description:

A female adult patient, who lost a permanent lower first molar, needed correction of the position of her permanent first molar place. Instead of making space for rehabilitation, it was closed after second molar uprighting and a balanced interdigitation was created without prosthetics. The patient was successfully treated with segmented arch technique using root correction spring activated with geometry VI to promote uprighting of a tipped molar and Niti spring coil to promote space closure.

Practical Implications:

Segmented arch technique is known to provide predictable light and continuous forces, which is very much indicated in adult treatment. There are several things to consider when orthodontically treating adult patients. Their periodontal conditions might not be ideal, less bone apposition may occur, and side effects of orthodontic tooth movement are expected. Thus, a predictable and controlled orthodontic treatment is needed.

Orthodontic Replacement of Lost Permanent Molar with Neighbor Molar: A Six-Year Follow-Up

Extraction is very frequent indication in orthodontic planning, especially when there are crowding, biprotrusion, and aesthetically unpleasant profiles. Next to extraction comes space closure, which represents a challenge for orthodontists because of extended treatment time, discomfort created for the patient, tissue tolerance, and stability concerns. When it comes to what mechanics to choose for space closure, loops present two major advantages in relation to sliding mechanics: absence of abrasion and possibility to reach pure dental translation. A case is presented where an adult female patient with early loss of the first lower permanent molars, minor lower crowding, and tooth biprotrusion was treated with upper first bicuspids extraction along with upper and lower space closure done with T-loops to promote best space closure control in order to correct the malocclusion and enhance facial aesthetics.

Importance of orthodontic movement in interdisciplinary treatment for restoring esthetics and functional occlusion

This article describes interdisciplinary treatment conducted in adult patients, 49-year-old, with periodontal problems, losses and dental inclination, occlusal trauma, localized bone loss, and necessity of rehabilitation with dental implants. Alignment and leveling of the teeth, the molars uprighting with cantilever, and space closure were performed the treatment was facilitated by periodic periodontal control. The resultant occlusion was stable throughout a 5-year retention period. In conclusion, interdisciplinary treatment combined with periodontics, orthodontics, implantodontist, and restorative dentistry was useful for improving the patient’s oral health, function, and esthetics.

Induced ankylosis of a primary molar for skeletal anchorage in the mandible as alternative to mini-implants

BACKGROUND

Mesial protraction of mandibular posterior teeth requires increased anchorage to avoid undesired tooth movements. Orthodontic mini-implants have become a popular and successful way to increase skeletal anchorage in such cases. However, mini-implants may cause injury to adjacent teeth or anatomical structures and may lead to tissue inflammation. Induced ankylosed primary teeth have been used in the past as abutments for the protraction of the maxilla in cases of maxillary retrognathism. However, this technique has not been described in the literature for the protraction of mandibular molars. The aim of this paper is to present, through a case report, an alternative to mini-implant devices to maximize anchorage in the mandible by inducing ankylosis on a primary molar.

FINDINGS

A 13-year-old female with class II right malocclusion, deep bite, and congenitally missing right second premolars was referred for orthodontic treatment. Treatment plan involved removal of the primary teeth and mesial protraction of the posterior. In the mandible, ankylosis was induced on the retained primary second molar by extraction, bisection, replantation of the mesial part after endodontic treatment, and bonding of a rigid splint. Ankylosis was diagnosed after 10 weeks and a closing T-loop sectional wire was inserted to move the permanent first molar mesially. At 6 months, the remaining space was closed using elastic chain on a rectangular stainless steel wire with tip-back bends, supported by class II elastics.

CONCLUSIONS

Induced ankylosis of primary teeth can be an alternative to orthodontic mini-implants in selected cases, with minimal risks and maximum biocompatibility.