Abstract: Implant therapy can provide a highly successful restoration of both function and esthetics in both completely and partially edentulous patient. To shorten the treatment period and to avoid the edentulous state of patients, it is recommended to perform the surgical techniques that would allow the immediate or early loading of implants. Many patients could not receive implants treatment because of financial problems so we present a case of single implant retained mandibular over denture with 6 months follow up.

INTRODUCTION

Many clinicians today recommend implant therapy for patients requiring tooth replacement. This therapy can provide a highly successful restoration of both function and esthetics in both completely and partially edentulous patient (Lee and Agar, 2006; Lee et al., 2009; Cochran, 2006; Ercoli et al., 2006).

In the last 30 years, use of unloaded and submerge implant for achieving osseointegration thought necessary (Stephan et al., 2007). Because of the prolonged period between implant placement and implant loading, problems such as patient and practitioner concerns with the long edentulous state in patients have been continuously debated. To shorten the treatment period and to avoid the edentulous state of patients, numerous studies have been performed on the surgical techniques that would allow the immediate or early loading of implants. Recent studies have shown that there is no difference between the use of 2-stage surgery according to Branemark protocol and one stage treatment protocol with immediate loading that was first arose when Ledermann introduced his modality with edentulous mandible (Lee et al., 2009; Attard and Zarb, 2005; Winter et al., 2004). When there is no indication for fixed restoration because of anatomical, functional and financial problems in mandible, implant-retained overdenture will be an optimal treatment (Stephan et al., 2007; Cannizzaro et al., 2008).

Highly implant success rate have also achieved by lots of studies using 2 or more implant to anchor an overdenture (Stephan et al., 2007; Bergendal and Engquist, 1998; Chiapasco et al., 2001; Payne et al., 2001). Because mandible is hinge-like and its buttressing lingual bone is shock absorbing, use of 2 implant is optimal for support and retention of overdenture and also some researches know this as a standard for edentulous mandible (Lee and Agar, 2006; Sadowsky and Caputo, 2004).

Use of ball 0-ring attachment could be advantages for implant supported overdentures with regard to optimizing stress and minimizing denture movement in comparison to bar attachments and magnets (Tokuhisa et al., 2003).

Yet many patients could not receive implants treatment because of financial problems and with regard to a recent studies that report immediate loaded single implant retained overdenture as a safe, reliable and cost effective treatment (Chiapasco et al., 2001; Liddelow and Henry, 2007, 2010; Kronstrom and Davis, 2010).

CLINICAL REPORT

A 45 years old woman presented, complaining of poor retention of mandibular denture and difficulty in eating and speaking. Teeth lost gradually due to caries. The patient had no significant problem in her medical history. About 1 year ago dentures were made for her according to prosthetic condition (neutral zone, occlusal plan and esthetics), dentures are acceptable.

PROCEDURE

A transparent stent was duplicated from mandibular denture with transparent self-cured acrylic and three holes was drilled in A, B and C positions (according to Misch category) (Misch and Bidez, 2008). These holes was filled by gutta percha (Aria dent, Iran ) and surface was painted by barium sulphate as radio opaque material. Bone condition and essential changes in implant position was determined by CBCT.

There was enough bone for insertion of implant (implantium/simple line II, Dentium; South Korea) with 10 mm length and 4 mm width in the C position.

The stent was used as surgical guide during placement and implant was insered with 30 N torque (NSK, Surgical Xt. Japan). Primary implant stability was measured with Ossstell (Integration Diagnostic, Gamlestadsvagen, Gotenburg and Sweden) at the end of surgery.

Digital parallel periapical radiography with a positioning stent was taken from patient immediately after the surgery and patient got her denture with proper ball attachment (implantium/simple line 2, Dentium, South Korea) in the first 48 h after the surgery (Stephan et al., 2007; Chiapasco and Gatti, 2003; Chiapasco et al., 2001) Amoxicilin (to prevent infection) 500 mg 3 times a day and Gelofen (to pain control) 400 mg 4 times a day was prescribed for patient. She was advised to use chlorhexidine mouth rinse (0/2%, Najo, Iran) 2 times a day. Also patient instructed to use soft diet for 6 weeks.

Patient followed for 1, 3 and 6 months after surgery and this parameter was evaluated:

RESULTS

Marginal bone loss was comparable to delay loading of implant and was 0.5 mm at 6 month, that was acceptable (Misch and Bidez, 2008). There were no signs of BOP and probe depth were not abnormal (3 mm). ISQ values were 70, 72, 75, 77 at the surgery, 1, 3, 6 months follow up, respectively (Fig. 1-3).

Fig. 1:	The 6 months after surgery

Fig. 2:	Mandibular denture

Fig. 3:	Peri apical radiograph: immediately (a) after surgery (b) after 6 month

CONCLUSION

Regarding to this case, application of one implant because of economic problems of patient is useful and is a starting point for ideal implant supported overdenture with more implants. Regarding to previous studies immediate loading of implant in anterior mandible has predictable result and can use for eliminating the edentulous phase of patients.