Randomized Controlled Trial Open Access
Copyright ©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Aug 26, 2024; 12(24): 5542-5548
Published online Aug 26, 2024. doi: 10.12998/wjcc.v12.i24.5542
Clinical efficacy, bone density, and follow-up in implant and orthodontic treatment for inclined adjacent teeth
Yi Yang, Shun-Cheng Zhou, Yi-Hui Ma, Xiang Wang, Qing-Shan Dong, Department of Stomatology, General Hospital of Central Theater Command, Wuhan 430012, Hubei Province, China
ORCID number: Qing-Shan Dong (0000-0003-2743-2156).
Author contributions: Yang Y performed the majority of experiments, wrote the manuscript, and served as scientific advisor; Zhou SC and Ma YH designed the study and revised the manuscript; Wang X contributed to analytical tools; Dong QS and Yang Y participated to the collection of the human material; Ma YH was the guarantor.
Institutional review board statement: The research was reviewed and approved by the Review Committee of General Hospital of Central Theater Command (Approval No. 05901).
Clinical trial registration statement: This study has not yet been registered with clinical trials.
Informed consent statement: All research participants or their legal guardians provided written informed consent prior to study registration.
Conflict-of-interest statement: No conflicts of interest are associated with this work.
Data sharing statement: No other data are available.
CONSORT 2010 statement: The authors have read the CONSORT 2010 statement, and the manuscript was prepared and revised according to the CONSORT 2010 statement.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Qing-Shan Dong, MD, Doctor, Department of Stomatology, General Hospital of Central Theater Command, No. 627 Wuluo Road, Wuhan 430070, Hubei Province, China. dentist417@163.com
Received: April 30, 2024
Revised: June 7, 2024
Accepted: June 20, 2024
Published online: August 26, 2024
Processing time: 71 Days and 18.2 Hours


Tooth defects can cause elongation of occlusal teeth, leading to insufficient repair space. The combination of dental implant restoration and orthodontic treatment of oblique adjacent teeth has a significant therapeutic effect.


To explore clinical efficacy, bone density, and follow-up of implant and orthodontic treatment for patients with inclined adjacent teeth.


In total, 98 patients with oblique adjacent teeth were randomly assigned to implant restoration combined with orthodontic treatment (group A, n = 49) or to receive implant restoration alone (group B, n = 49). Changes in alveolar ridge bone density and apical bone density were observed before and after treatment in the two groups. Changes in chewing function and language function were compared between the two groups of patients. Follow-up lasted for 12 mo after repair to observe any adverse reactions in the oral cavity.


The clinical effective rates of group A and group B were 97.96% and 85.71%, respectively, with group A having a higher clinical effective rate than group B. After treatment, the bone density of the alveolar ridge and apical bone in both groups decreased compared to before treatment, while the chewing and language functions improved. The changes in various indicators in group A were more significant. After treatment, the satisfaction rate of group A (97.96%) was higher than that of group B (79.59%). The incidence of adverse reactions in group A (2.04%) was lower than that in group B (24.49%).


The amalgamation of implant restoration and orthodontic treatment for adjacent tilted teeth demonstrates notable clinical efficacy, diminishes alveolar bone resorption, and fosters patient functional rehabilitation while exhibiting negligible adverse reactions.

Key Words: Dental implant restoration, Orthodontic correction, Tilt adjacent teeth, Clinical curative effect, Alveolar bone mineral density

Core Tip: If dental defects are not repaired in a timely manner, adjacent teeth may tilt and shift. This causes elongation of the occlusal teeth, results in a lack of sufficient repair space, and leads to certain difficulties in the restoration of dentures. The combination of dental implant restoration and orthodontic treatment for tilted adjacent teeth has significant therapeutic effects, can reduce alveolar bone density, promote patient functional recovery, and is safe.


Dental defects resulting from caries, trauma, and congenital dysplasia are commonly encountered in clinical practice. These conditions not only significantly impact patients’ masticatory function, speech articulation, and aesthetic appearance but also exert implications on the stomatognathic system and overall health[1]. Untimely repair of dental defects may lead to adjacent teeth misalignment and occlusal tooth elongation resulting in insufficient space for restoration, thereby posing challenges to denture rehabilitation[2].

With societal advancements and lifestyle changes coupled with an increased emphasis on self-image, there has been a rising trend in patients opting for dental restoration. Implant-supported dentures have emerged as a well-established and reliable modality for tooth replacement in contemporary dental care, offering advantages such as minimal invasiveness, reduced foreign body sensation, stability, and functional integrity. Nevertheless, not all patients meet the eligibility criteria for implantation[3]. In cases where implantation is hastily pursued without adequate tooth space, it can lead to improper occlusion and potential implant failure. Moreover, inadequate alveolar bone quality presents a significant challenge to successful implant therapy.

Bone augmentation and orthodontic intervention serve as pivotal approaches to address bone deficiencies[4]. The synergy between implant-supported dentures and orthodontic treatment is evident, with the latter facilitating sufficient space and optimal alveolar bone conditions for successful implant placement[5]. This study aimed to investigate the clinical efficacy and alveolar bone mineral density (BMD) outcomes of patients with inclined adjacent teeth who underwent combined implant restoration and orthodontic correction at our institution between May 2018 and January 2020. Subsequent patient follow-up and reevaluation were comprehensively analyzed to assess treatment effectiveness.


A total of 98 patients with oblique adjacent teeth treated in General Hospital of Central Theater Command from May 2021 to January 2023 were randomly divided into the study group (group A) (n = 49) and control group (group B) (n = 49). Among them, there were 29 males and 20 females in the study group, aged 21-54 years, with an average age of 38.66 ± 14.46 years. In the control group, there were 30 males and 19 females, aged from 23-years-old to 53-years-old, with an average age of 39.49 ± 14.64 years. There were no significant differences in age and other basic data between the two groups (P > 0.05). Method patients in group B underwent solely implant restoration treatment.

Inclusion criteria

(1) Age between 20 years and 60 years; (2) Absence of neurological impairments allowing for treatment cooperation; (3) Presence of long-term tooth loss with adjacent dental inclination necessitating orthodontic intervention rather than denture implantation; (4) Approval from the hospital ethics committee adhering to medical ethics standards; and (5) Documented informed consent from patient and their family.

Exclusion criteria

(1) Pregnancy or lactation; (2) Coagulation dysfunction; (3) Hepatorenal or cardiac insufficiency; (4) Bone metabolic disorders; and (5) Inability to maintain oral hygiene independently.


Preoperative X-ray images were obtained to assess the oral condition, particularly the relationship between the implant site and adjacent structures, aiding in the selection of appropriate implant systems and components. Prior to the procedure, patients received routine administration of cephalosporin, metronidazole, and other medications for prophylaxis, along with oral and maxillofacial region disinfection. Local anesthesia was administered before making an incision in the gingiva to expose the alveolar bone. High-speed mobile phones and ball drills were utilized to create holes in the alveolar bone, gradually expanding them to accommodate the implants. Implants were then carefully inserted into the prepared sockets, with meticulous attention paid to the protection of adjacent teeth. Subsequently, dentures were fitted to optimize the maxillary arch alignment. Patients were instructed on oral hygiene practices, and stitches were typically removed 1 wk post-implantation.

Patients in group A received a comprehensive treatment approach involving both implant restoration and orthodontic intervention. Initially, X-ray imaging was employed to assess the extent and distribution of missing teeth. Following this, oral cleaning procedures were performed to prepare the mouth for subsequent treatment. Orthodontic techniques were then utilized to rectify malocclusions, focusing on aligning both upper and lower dentitions. Additionally, adjustments were made to the positions of abutment teeth, canines, and other adjacent teeth to optimize dental occlusion and alignment. Following the completion of orthodontic treatment, patients underwent implant restoration procedures to replace missing teeth.

Observation index clinical efficacy assessment encompassed the evaluation of therapeutic outcomes in both study groups and were categorized as effective, partially effective, and ineffective. Noteworthy effectiveness was characterized by stable implant fixation, aesthetically pleasing and satisfactory restorations, and restored normal masticatory function. Partial effectiveness denoted stable implant fixation with occasional loosening, improved restoration aesthetics, and satisfactory enhancement of masticatory function. Ineffectiveness was defined by implant damage or loosening, lack of improvement in masticatory function, and the presence of inflammation.

Alveolar BMD alterations, specifically at the crest and apical regions, were quantified via X-ray imaging to assess changes before and after treatment in both study cohorts. The masticatory and language functions of participants were evaluated utilizing the Eichner classification system, with a maximum score of 10 indicating optimal patient recovery. Higher scores correlated with improved functional outcomes. Patient satisfaction was gauged using a self-designed satisfaction assessment tool, with ratings including “very satisfied,” “satisfied,” and “dissatisfied.” Scores ranged from 0 to 100, with ratings above 85 indicative of very high satisfaction, 55-85 indicating satisfaction, and scores below 55 representing dissatisfaction. Follow-up examinations were conducted after 12 mo post-treatment to monitor the occurrence of oral adverse reactions. Patients were advised to prioritize oral hygiene and maintain regular dental cleanings to optimize oral health outcomes.

Statistical analysis

In this study, a comparison of clinical efficacy, satisfaction, and the incidence of adverse reactions between group A and group B was conducted using the χ2 test, with results expressed as n (%). The alveolar BMD, masticatory function, and language function of both groups were evaluated using independent sample t-tests, with results presented as mean ± standard deviation. Statistical analyses were performed using SPSS 18.0 (IBM Corp., Armonk, NY, United States), with significance determined at P < 0.05.


The clinical effective rates of group A and B were 97.96% and 85.71%, respectively, and the clinical effective rate of the group A was higher than group B (Table 1). After treatment, the alveolar crest BMD and apical BMD in the two groups were reduced than before treatment, and those in group A were reduced more than group B (Table 2). After treatment, the masticatory function and language function of the two groups were increased than those before treatment. The masticatory function of group A was higher than group B (Table 3). After treatment, the satisfaction of patients in group A and group B was 97.96% and 79.59%, respectively, and the satisfaction in group A was higher than group B (Table 4). There was only 1 case of implant loosening in group A, and the incidence of adverse reaction was 2.04%. In group B, there were 41 cases of gingivitis, 41 cases of periodontal discomfort, 7 cases of implant loosening, and 3 cases of root resorption. The incidence of adverse reaction was 24.49%. The level in group A was decreased compared to group B (Table 5).

Table 1 Proportion of clinical efficacy.
Significant effect
Total effective
A4935 (71.43)13 (26.53)1 (2.04)48 (97.96)
B4927 (55.10)15 (30.61)7 (14.29)42 (85.71)
P value0.027
Table 2 Comparison of alveolar bone mineral density.
GroupnAlveolar crest parietal bone mineral density in g/cm2
t value
P value
Apical bone mineral density in g/cm2
t value
P value
Before treatment
After treatment
Before treatment
After treatment
A49350.28 ± 25.37327.36 ± 26.604.365< 0.001332.23 ± 11.58308.09 ± 12.629.866< 0.001
B49350.54 ± 23.63339.17 ± 25.162.3060.023331.28 ± 14.73300.04 ± 15.7510.141< 0.001
t value0.0532.2580.3552.792
P value0.9580.0260.7230.006
Table 3 Comparison of masticatory function and language function.
Masticatory function
Language function
A49Before treatment4.68 ± 1.244.82 ± 0.98
After treatment9.39 ± 0.39a,b9.25 ± 0.22a,b
B49Before treatment4.75 ± 1.364.85 ± 1.03
After treatment7.13 ± 0.40a7.05 ± 0.47a
Table 4 The proportion of patient satisfaction.
Very satisfied
Not satisfied
A4939 (79.59)9 (18.37)1 (2.04)48 (97.96)
B4923 (46.94)16 (32.65)10 (20.41)39 (79.59)
t value8.295
P value0.004
Table 5 Proportion of oral adverse reactions.
Periodontal discomfort
Implant loosening
Root resorption
Total490 (0.00)0 (0.00)1 (2.04)0 (0.00)1 (2.04)
B491 (2.04)1 (2.04)7 (14.29)3 (6.13)12 (24.49)
P value0.001

Dentition defects denote variations in the number of missing teeth across different regions of the dentition, thereby compromising the patient’s masticatory function, speech articulation, and aesthetic appearance. Investigations reveal persistently high prevalence rates of dentition defects and periodontal diseases. Untimely restoration of missing teeth may precipitate adjacent teeth tilting and shifting towards the edentulous spaces, while opposing teeth may elongate due to lack of occlusal contact, resulting in occlusal discrepancies, food impaction, and potential periodontal tissue damage[6]. Furthermore, dental and skeletal atrophy may ensue, leading to facial asymmetry and consequent impairment of masticatory function and nutrient absorption[7]. Such conditions exert a significant impact on the patient’s oral and maxillofacial complex as well as overall systemic health.

As social and economic advancements continue alongside progress in medical science and technology and with an evolving clinical repair ethos, there is a growing patient inclination towards aesthetically pleasing, minimally invasive treatment modalities. In contrast to conventional fixed and removable partial dentures, implant restoration offers distinct advantages including minimal tissue disruption, reduced foreign body sensation, stability, and optimal functionality. Furthermore, implant restoration facilitates superior aesthetic outcomes, occlusal function, and physiological efficacy while preserving the integrity of adjacent teeth. Consequently, it has emerged as a well-established and dependable method for edentulous reconstruction in contemporary dental care[8,9].

Nevertheless, not all patients meet the criteria for implantation adaptation. The decision for repair often hinges on aesthetic or functional concerns arising from missing teeth, typically manifesting with symptoms such as narrowed interdental spaces due to adjacent tooth displacement or occlusal tooth intrusion as well as an increase in scattered spaces, among others. Failure to address these issues promptly may impede subsequent treatment steps. Some researchers posit that establishing a harmonious occlusal relationship is pivotal in preventing bone resorption and occlusal trauma in implant-supported restorations[10]. Consequently, even in cases where implantation and repair are deemed necessary, achieving optimal harmony between function and aesthetics remains challenging. Hence, orthodontic intervention targeting inclined adjacent teeth and depressed elongated molars becomes essential to create adequate space and establish a favorable occlusal relationship for restoration.

Orthodontic measures serve to close interdental gaps, realign adjacent teeth towards edentulous spaces, and augment implant placement areas. Concurrently, implant therapy facilitates denture restoration, thereby fulfilling corrective and aesthetic objectives. This integrated approach effectively enhances patients’ oral function, promoting overall oral health and well-being[11,12].

This study found that orthodontic intervention combined with implant therapy was minimally invasive, which can reduce the damage caused by grinding tooth tissue and reduce the trauma of occlusal by depressing the extended teeth, restoring the distance between the jaws and the gingiva and improving the efficiency and life of the implant[13]. The results of this study found that implant restoration combined with orthodontic treatment of inclined adjacent teeth had an obvious clinical effect, improved patient dental aesthetic satisfaction, and reduced the probability of adverse reactions.

Patients with dental defects often present with varying degrees of alveolar bone destruction, resulting in diminished bone mass, reduced periodontal ligament area, and alveolar ridge atrophy. These anatomical challenges pose significant obstacles to orthodontic interventions. Research indicates that during orthodontic tooth movement, the rate of alveolar bone resorption accelerates, leading to increased tooth mobility[14]. The health status of alveolar bone can be reflected by many aspects, among which BMD is an important index. BMD refers to the unit bone volume and the average bone mineral content of the noodle machine, which is not only an important index to reflect the cooling but also a sensitive index to reflect the severity of the disease[15].

The results of this study showed that implant restoration combined with orthodontic treatment of inclined adjacent teeth could reduce the BMD of the alveolar crest and apical area, improve the masticatory function and language function, and promote the recovery of patients. Implant restoration combined with orthodontic treatment of inclined adjacent teeth can play a significant clinical effect, reduce alveolar BMD, and promote the functional recovery of patients. After restoration, it was found that there were no obvious adverse reactions in implant restoration combined with orthodontic treatment.


The findings of this study demonstrated that the combination of implant restoration and orthodontic correction in patients with adjacent maloccluded teeth yielded superior clinical efficacy, improved alveolar bone density, enhanced masticatory and language functions, and reduced incidence of adverse reactions compared to implant restoration therapy alone. This method merits widespread clinical application. However, due to the limited number of participants, statistical significance may be affected, potentially reducing the reliability and representativeness of the results. Future directions may involve multicenter studies recruiting participants from various regions to ensure sample diversity and result generalizability.


Provenance and peer review: Unsolicited article; Externally peer reviewed.

Peer-review model: Single blind

Specialty type: Medicine, research and experimental

Country of origin: China

Peer-review report’s classification

Scientific Quality: Grade C

Novelty: Grade C

Creativity or Innovation: Grade B

Scientific Significance: Grade B

P-Reviewer: Reito A S-Editor: Liu H L-Editor: Filipodia P-Editor: Chen YX

1.  Tribst JPM, Dal Piva AMO, de Jager N, Bottino MA, de Kok P, Kleverlaan CJ. Full-Crown Versus Endocrown Approach: A 3D-Analysis of Both Restorations and the Effect of Ferrule and Restoration Material. J Prosthodont. 2021;30:335-344.  [PubMed]  [DOI]  [Cited in This Article: ]  [Cited by in Crossref: 11]  [Cited by in F6Publishing: 11]  [Article Influence: 2.8]  [Reference Citation Analysis (0)]
2.  Dal Piva AMO, Tribst JPM, Benalcázar Jalkh EB, Anami LC, Bonfante EA, Bottino MA. Minimal tooth preparation for posterior monolithic ceramic crowns: Effect on the mechanical behavior, reliability and translucency. Dent Mater. 2021;37:e140-e150.  [PubMed]  [DOI]  [Cited in This Article: ]  [Cited by in Crossref: 13]  [Cited by in F6Publishing: 14]  [Article Influence: 3.5]  [Reference Citation Analysis (0)]
3.  Zhang S, Lü C, Li JH, Zhu BM, Wang WQ. [Three-dimensional finite element analysis of the influence of an abutment buffer layer on implant stress distribution]. Hua Xi Kou Qiang Yi Xue Za Zhi. 2020;38:537-540.  [PubMed]  [DOI]  [Cited in This Article: ]  [Cited by in F6Publishing: 1]  [Reference Citation Analysis (0)]
4.  Li N, Li Y, Gao Y, Jiang L. Biomechanical Assessment of Tilted Mandibular Second Molars with Full-Crown Adjacent to Implant-Supported Restoration: 3D Finite Element Analysis. Int J Gen Med. 2022;15:3459-3470.  [PubMed]  [DOI]  [Cited in This Article: ]  [Reference Citation Analysis (0)]
5.  Abdelhady NA, Tawfik MA, Hammad SM. Maxillary molar distalization in treatment of angle class II malocclusion growing patients: Uncontrolled clinical trial. Int Orthod. 2020;18:96-104.  [PubMed]  [DOI]  [Cited in This Article: ]  [Cited by in Crossref: 6]  [Cited by in F6Publishing: 10]  [Article Influence: 2.5]  [Reference Citation Analysis (0)]
6.  Balina S, Karri T, Indugu V, Gade RR, Meher Vineesha C, Likhita C. Prevalence and Distribution of Malocclusion Using Dewey's Modification in Coastal Andhra Pradesh, India: A Cross-Sectional Study. Cureus. 2023;15:e42965.  [PubMed]  [DOI]  [Cited in This Article: ]  [Reference Citation Analysis (0)]
7.  de Oliveira Meira ACL, Custodio W, Vedovello Filho M, Borges TM, C Meneghim M, Santamaria M Jr, Vedovello SAS. How is orthodontic treatment need associated with perceived esthetic impact of malocclusion in adolescents? Am J Orthod Dentofacial Orthop. 2020;158:668-673.  [PubMed]  [DOI]  [Cited in This Article: ]  [Cited by in Crossref: 6]  [Cited by in F6Publishing: 7]  [Article Influence: 1.8]  [Reference Citation Analysis (0)]
8.  Frias Cortez MA, Bourauel C, Reichert C, Jäger A, Reimann S. Numerical and biomechanical analysis of orthodontic treatment of recovered periodontally compromised patients. J Orofac Orthop. 2022;83:255-268.  [PubMed]  [DOI]  [Cited in This Article: ]  [Reference Citation Analysis (0)]
9.  Kouskoura T, Ochsner T, Verna C, Pandis N, Kanavakis G. The effect of orthodontic treatment on facial attractiveness: a systematic review and meta-analysis. Eur J Orthod. 2022;44:636-649.  [PubMed]  [DOI]  [Cited in This Article: ]  [Cited by in F6Publishing: 6]  [Reference Citation Analysis (0)]
10.  Kirschneck C, Proff P, Lux C. Ideal treatment timing of orthodontic anomalies-a German clinical S3 practice guideline. J Orofac Orthop. 2022;83:225-232.  [PubMed]  [DOI]  [Cited in This Article: ]  [Reference Citation Analysis (0)]
11.  Di Guida LA, Collares KF, Borba M, Matias M, Benetti P. Predictors of orthodontic treatment conclusion: A historical cohort study. Am J Orthod Dentofacial Orthop. 2021;159:e179-e185.  [PubMed]  [DOI]  [Cited in This Article: ]  [Reference Citation Analysis (0)]
12.  Lee SA, Chang CCH, Roberts WE. Severe unilateral scissors-bite with a constricted mandibular arch: Bite turbos and extra-alveolar bone screws in the infrazygomatic crests and mandibular buccal shelf. Am J Orthod Dentofacial Orthop. 2018;154:554-569.  [PubMed]  [DOI]  [Cited in This Article: ]  [Cited by in Crossref: 14]  [Cited by in F6Publishing: 14]  [Article Influence: 2.3]  [Reference Citation Analysis (0)]
13.  Xie XJ, Li S, Bai YX. Early orthodontic treatment of malocclusion in the mixed dentition. Zhonghua Kou Qiang Yi Xue Za Zhi. 2022;57:805-810.  [PubMed]  [DOI]  [Cited in This Article: ]  [Reference Citation Analysis (0)]
14.  Li B, Kyung HM. Identification of eight meta-signature miRNAs as potential biomarkers for oropharyngeal cancers. Cancer Genet. 2019;233-234:75-83.  [PubMed]  [DOI]  [Cited in This Article: ]  [Cited by in Crossref: 4]  [Cited by in F6Publishing: 4]  [Article Influence: 0.7]  [Reference Citation Analysis (0)]
15.  Xie J, Huang C, Yin K, Park J, Xu Y. Effects of orthodontic treatment with activator appliance on patients with skeletal Class II malocclusion: a systematic review and meta-analysis. Ann Palliat Med. 2021;10:12319-12334.  [PubMed]  [DOI]  [Cited in This Article: ]  [Reference Citation Analysis (0)]