Assessment of Oral Health-Related Quality of Life for Complex Mandibular Defects Rehabilitated with Computer-guided Implant Restoration.

The individuals who have been afflicted with mandibular defects involving soft and hard tissue loss are subjected to functional, psychological and social consequences. Rehabilitation is of prime importance in restoring self confidence and improving the quality of life. Complex mandibular defects can be successfully rehabilitated with the three dimensional (3D) computerized diagnostic technique (Simplant-Dentsply sirona implant). one of the important tools for measuring the oral health status by scale knows as oral health impact profile (OHIP). OHIP is a scale particularly designed to measure the quality of life and its influence pertaining to functional and psychological aspects. This report describes the prosthetic rehabilitation posttraumatic mandibular defect with 3D SimPlant software and stereolithography. With the application of computer-aided design/computer-aided manufacturing technology, guided implant prosthesis could definitely improve masticatory performance and esthetics, thereby enhancing oral health-related quality of life.

INTRODUCTION

Rehabilitation of maxillofacial structures becomes a more challenging task because of the complex anatomy and the defects involving various vital structures. Mandibular defects mainly due to trauma often results in strong impact on functional, psychological, and aesthetic well being of the individuals. The ultimate goals of rehabilitation are mainly to restore maxillomandibular relationship, occlusion, function, and esthetics.

There are numerous treatment modalities available for restoring mandibular defects. Routine treatment options for mandibular defects include the use of conventional tooth/tissue-supported prosthesis and implant-retained/supported prosthesis. Meanwhile, with conventional prosthodontic rehabilitation, patients regain some mastication ability; they gain the most favorable masticatory outcomes with implant-retained prosthodontic treatment. Removable dental prosthesis may not be the suitable treatment option due to the insufficient keratinized tissue, poor tissue tolerance and the presence of skin graft. Dental implants[5] are considered to be a predictable treatment for restoring mandibular defects. Accurate preoperative planning of implant size and location and designing of restorations are successfully possible only with advanced computer-aided design/computer-aided manufacturing (CAD/CAM) technology.[6]

The primary goal of rehabilitation of these defects is to enhance the quality of life. Quality of life[7] has become the focus of attention during recent years in maxillofacial defects; patient's psychological well-being and the patients’ vitality are increasingly contributing to the evaluation of therapeutical success.

The oral health impact profile[8] (OHIP) is a specifically designed scale to assess the impact of oral health on psychological well-being and quality of life. This clinical report describes the assessment of oral health-related quality of life (OHRQoL) for complex mandibular defects rehabilitated with computer-guided implant restoration.

CASE REPORT

A young male patient aged 23 years reported to the Department of Prosthodontics and Crown and Bridge of Vinayaka Mission's Sankarachariyar Dental College, Salem, Tamil Nadu, India, with a right-side defect of his mandible.

The patient met with a road traffic accident roughly about 4 years back and had been treated with various surgeries to correct the mandibular defects. Informed consent was obtained. Thorough clinical and radiographic examination revealed extensive buccal and lingual soft-tissue loss and alveolar bone loss of mandibular right-sided region [Figure 1a and b]. The right-sided central incisors, lateral incisors, canine, premolars, and 1st molar were missing. All other remaining teeth in the mandibular arch were clinically healthy.

Figure 1

Pretreatment intraoral condition of the right mandibular continuity defects (a, right lateral view and b, left lateral view)

The patient was thoroughly evaluated, and appropriate treatment modalities were recommended. Due to the inadequate keratinized tissue and lack of soft- and hard-tissue support and patient's desires, removable dental prosthesis may not be the ideal solution. In spite of significant bone loss, considering dental implants to be the ideal treatment option, implant-supported fixed dental prosthesis was planned with three implants. A treatment was planned with Simplant guided surgery (Densply- Sirona implants) for determining the position and size of endosseous root form implants (BioHorizons implant system) [Figures 2 and 3].

Figure 2

Planning and positioning of implants using Simplant software

Figure 3

Planning and designing of restoration using Simplant software

Maxillary and mandibular alginate (irreversible hydrocolloid) impressions were made and poured with type IV die stone for fabrication of surgical guide's template. The planned implant size in region of 1st molar, premolar, and canine was 4.6/9 mm, 3.8/10.5 mm, and 3.8/10.5 mm, respectively. Based on the planned implant size, 3-resin model surgical guide templates were designed and fabricated with stereolithography [Figure 4]. The patient was comfortably seated and inferior alveolar nerve block was administered at the site of implant placement. The implants were guided with tooth supported surgical guides [Figure 5] and three endosseous implants were placed in molar, premolar and canine region. The cover screw were then placed on the implants and surgical site were sutured with 3-0 silk, simple interrupted sutures [Figures 6 and 7]. Final implant positions were evaluated with panoramic radiograph [Figure 8]. The patient was recalled after 5 months for placement of gingival healing abutments [Figure 9]. Final impressions were made with polyvinyl siloxane (putty-wash) impression technique 10 days after placement of healing abutment [Figure 10]. Basic maxillomandibular relationship is maintained in continuity defect, and the records were obtained using the bite block and bite registration material. The master casts were then transferred to a semi-adjustable articulator (Hanau Wide-Vue). Since the vertical height of defect was >15 mm in length, customized abutments [Figure 11] (UCLA) were planned and definitive prostheses were fabricated. Four-unit metal ceramic restorations (FP-3) were cemented, and follow-up instructions were provided [Figure 12a and b]. Postoral hygiene maintenance instructions were given.

Figure 4

Resin-based surgical guides fabricated by stereolithography technology

Figure 5

Position of tooth-supported surgical guides

Figure 6

Placement of endosseous implant by surgical guide sequences

Figure 7

Implant placement with cover screw

Figure 8

Panoramic radiograph of endosseous implants after placement

Figure 9

Healing abutment placement

Figure 10

Position of ball abutment for impression making

Figure 11

Customized UCLA abutment

Figure 12

Final restoration in place (a, occlusal view and b, right lateral view)

OHRQoL was assessed for a period of 2 weeks and 3 months of prosthesis function using obturator functioning scale and OHIP. Significant improvement was observed in functional, physical, psychological, and social subscales of OHIP.

No clinical complications were observed during the 2-year follow-up period.

DISCUSSION

Rehabilitation of mandibular defects is challenging due to the complex anatomy and the defects involving various vital structures.[9] The primary aim of restoration is mainly to restore function, occlusal relationship, and appearance.[1011]

Results are promising with advanced diagnostic technology by precise preoperative planning and designing of patient-specific implant location and restorations preoperatively and thereby exhibiting excellent esthetic and functional outcomes.[121314]

This case report provides a simple method for rehabilitation of complex three-dimensional (3D) structures with advanced computerized technology. The use of rapid prototyping 3D stereolithography models[1516] has revolutionized the way of reconstruction for planning of complex craniofacial structures.

To fabricate a customized stereolithographic drill guide,[1718] the cone-beam computed tomography (CBCT) with Simplant, a software to easy facilitate, is very helpful. The planned surgical drill guide helps in accurate placement of implant which is otherwise a very difficult and cumbersome procedure.[19] The treatment outcome becomes more predictable for both the patient and the clinician. Prosthetically driven implantology is possible only with 3D Implant planning with Simplant software in complex mandibulectomy patients.[2021]

With the CBCT, the anatomical structures which are close to the site such as teeth, sinus, nerves, and arteries can be assessed accurately and planned, and even the best soft-tissue thickness can be measured and planned accordingly with Simplant guide.[22] The treatment plan with Simplant indirectly helps in the OHRQoL of the patients because it simplifies the procedure, thereby minimizing the complications and surgical abuse.

John et al. characterized the index OHRQoL. OHIP is a self-administered instrument and a specifically designed scale to measure the impact of oral health on psychological well-being and quality of life.

In this clinical procedure, there was a significant improvement in OHRQoL after rehabilitation with implant-supported mandibular prosthesis.

CONCLUSION

The important aspect in rehabilitation of complex mandibular defects involves careful, thorough evaluation of the patient's anatomy to describe the full extent of the existing or proposed defect.

Advances in technologies can be very useful when formulating a plan and design of the implant restoration for mandibular defects.

CAD/CAM systems have been used for restoring complex mandibular defects with implant-supported fixed restorations because they facilitate the accurate position of endosseous implants and design of fixed restorations.

CLINICAL APPLICATIONS

CAD/CAM technology is applied in creating a successful implant-supported restoration in complex mandibular defects with respect to masticatory ability, structural balance, occlusal equilibrium, and esthetics. Thereby, it helps improve the quality of life of patients.

DECLARATION OF PATIENT CONSENT

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

FINANCIAL SUPPORT AND SPONSORSHIP

Nil.

CONFLICTS OF INTEREST

There are no conflicts of interest.